1988 Fall Meet ing TCD-88-F

T e c h n i c a l C o m m i t t e e D o c u m e n t a t i o n

A Compilation of the Documented Action on Comments Received by the Technical Committees Whose Reports Have Been Published

Prior to Consideration at the NFPA Fall Meeting

Opryland Hotel Nashville, Tennessee

November 14-17, 1988

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Copyright © 1988 All Rights Reserved

National Fire Protection Association, Inc. Batterymarch Park, Quincy, MA 02269

19.2M-9-88-TCD Printed in U.S.A.

SUPPLEMENTARY

Report of Committee on Boiler-Furnace Exploslons

James K. Lafontaine, Chairman Penelec

Courtney D. Alvey, Lu therv i l le , HD Willlam H. Axtman, Am. Boi ler Hanufacturers Assoc. R. R. Beal, Bailey Controls Inc. John A. Brown, Foster Wheeler Energy Corp. Paul L. C io f f l , Babcock & Wilcox C. W. Conaway, Industr ia l Risk Insurers William E. Cunnlngham Jr . , Ri ley Stoker Corp. Dale E. Dressel, Monsanto Co. 3ohn L. Edler, Baltlmore Gas & E lec t r ic Co. Humphrey Fedorak, E I duPont de Nemours & Co. Frank H. Fishlock, Fenwal Inc.

Rep. FSSA Ronald E. Fr ingel i , H&M Protection Consultants Robert L. Gruehn, Kemper Group

Rep. AAI Thomas B. Hamilton, Hamilton Consulting Services, Inc. Warren G. Hudson, Union Carbide Corp. Albert L. Lake, In t l Union of Operating Engineers Kenneth N. Lawrence, Honeywell Inc.

Rep. NEMA Donald J. L. Lin, Oui l in Inc. Robert H. Lundberg, Los Altos, CA Peter B, Matthews, Hartford Steam Boi ler Insp. & Ins. Co. Jerry Moskal, Combustion Engineering Inc. Raymond J. Murphy, Forney Engineering J. M, Simmons, Factory Mutual Research Corp. Paul H. Sutphen, Public Service E lec t r ic & Gas Co, Robert F. Tomczak, Tampa Elect r ic Co.

Rep. EEI Enno Toomsalu, Underwriters Laboratories Inc.

Alternates

Robert S. E1ek, Kemper Group (Alternate to R. L. Gruehn)

Tommy E. England, Industrial Risk Insurers (Alternate to C. W. Conaway)

Roger W. Malone, Union Carbide Corp. (Alternate to W. G. Hudson)

Russell N. Mosher, American Boi ler Manufacturers Assn. (Alternate to W. H. Axtman)

C. Dudley Orr, American Petroleum Ins t i t u te (Alternate to API Rep.)

J. C. Waung, Babcock & Wilcox Co. (Alternate to P. L. C io f f l )

This l i s t represents the membership at the time the Committee was balloted on the text of this edition. Since that time, changes in the membership may have occurred.

The Supplementary Report of the Committee on Boiler-Furnace Explosions is presented for adoption in 2 parts.

Part I of this Supplementar~ Report was prepared by the Technical Committee on Boiler-Furnace Explosions, and proposes for adoption a Supplementary Report which documents i ts action on the publlc comments received on its Report on NFPA 85H, Standard for Prevention of Combustion Hazards in Atmospheric Fluldlzed Bed Combustion System Boilers, published in the Technical Committee Reports for the 1988 Fall Meeting.

Part I of this Supplementary Report has been submitted to le t ter ballot of the Technical Committee on Boiler-Furnace Explosions which consists of 28 votin~ members; of whom 24 voted affirmatively, 1 negatlvely (Mr. Tomczak),and 3 ballots were not returned (Messrs. Cunnlngham, Lake and Orr).

Mr. Tomczak voted negatively stat ing: "At th is stage, f lu id ized bed technology is s t i l l

emerging with prototype and demonstration units current ly discovering operation and design problems. Many of these problems have not been solved. Introduction of a standard at th is time would be unfair to the manufacturer and the users, pa r t i cu la r l y as you increase in unit size. Some of the information in this document is useful, but the ZO/ZO vis ion of the future is highly suspect. Let 's not place a constraint on th is future and the c rea t i v i t y of engineers and designers within our industry. I feel that th is document should be a "guidel ine" at this time, and propose that i t be considered as a standard during the next cyc le."

Hr. Fr ingel i voted a f f i rmat ive ly but had the fo l lowing comment:

"Log #9: I am not sure that the Committee intended to use word "~as-f i red" in f i r s t sentence of subsection 1-2.2 in Committee Action section.

Mr. Brown voted a f f i rmat ive ly but had the fol lowing comment :

"This forms a good basis for a Fluidtzed Bed Standard. However, we have serious concerns, especial ly about in-bed lances.

In-bed fuel lances d i f f e r from conventional burners used in u t i l i t y and industr ia l boi lers in three ways.

1. They are not igni ted ind iv idua l l y from a dedicated ign i t ion source. They are ignited from the hot-bed materlal into which the lance is spraying fuel.

2. They are not normally provided with the i r own source of combustion a i r . The a i r for combustion is provided from excess a i r avai lable in the bed i t s e l f from the primary a i r source.

In th is regard, two permlssives are required: a. that the bed temperature be high enough to

ign i te the aux i l i a ry fuel from the lance; b. that a i r be avai lable to support the combustion

of the aux i l i a ry fuel . The bed temperature permissive is outl ined in this

standard. The requirement for adequate combustion a i r is not, and we recommend that i t be addressed.

Since lances are normally used during the bed preheating stage of star t -up, su f f i c ien t a i r should be avai lable. But i f i t is not, a real danger of explosion ex is ts , especia l ly i f raw fuel enters the furnace, finds insu f f i c ien t a i r for combustion, and then the operator increases a i r f low.

5-1.5(g) The standard requires bed temperature to be at 1,400°F before in-bed lances can be f~red. We think ],400°F is unreasonable. Several of our units use propane as an aux i l i a ry fuel . Propane has an ign i t ion temperature of 920°F in an ox id iz ing atmosphere. To raise the bed temperature to 1,400°F requires a much larger in-duct burner. In fact, most coals w i l l sel f -sustain at 1,4gO°F; so i f this temperature is required for in-bed lances, the need for in-bed lances is negated.

We suggest that 5. ] .S(g) be changed to read "Bed lances shall be "locked out" of operation unt i l the average bed temperature exceeds the ign i t ion temperature of the aux i l i a ry fuel in an ox id iz ing atmosphere by a minimum of 200°F. '' A lower bed temperature w i l l be permitted (but not lower than 900UF), provided the temperature has been ver i f ied thrbugh test and actual experience to safely ign i te the aux i l i a ry fuel .

(Note 4- l .2.2(F)2 on page 5 should read [See 5-1.5.1(g) . . . . not (h ) ] ) . 3. The third area that differentiates in-bed lances

from conventional burners is "flame detection." In-bed lances do not have dedicated flame detectors. The only indicat ion of successful f i r i n g of in-bed lances is an increase in bed temperature. The operator should be aware that i f an increase in bed temperature does not occur within a reasonable time, combustion of the lance fuel is most l i k e l y unsuccessful and steps must be taken--the minimum step being to t r ip the in-bed lances.

In summary, we are very concerned about the standards for in-bed lances. The lances are

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essent la l ly open pipes pumping raw fuel ( l i qu id or gaseous) in to a dense medium without the benef i t of a dedicated ign i t ion source, a source of combustion a i r or a flame detector. We bel ieve that the standard should address th is area in considerable d e t a i l . "

Part I I of th is Supplementary Report was prepared by the Technlcal Committee on Boiler-Furnace Exploslons, and proposes for adoption a Supplementary Report which documents i t s action on the publlc comments received on i t s Report on NFPA 85I, Recommended Practice for Stoker Operation, published in the Technical Committee Reports for the 1988 Fall Meetlng,

Part I I of th is Supplementary Report has been submitted to l e t t e r ba l lo t of the Technlcal Committee on Boiler-Furnace Explosions which consists of 28 voting members; of whom 24 voted a f f i rmat ive ly , 0 negat lvely, and 4 ba l lo ts were not returned (Messrs. Cunningham, Lake, Moskal and Orr).

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PART I

~Log #41) 85H- 1 - (Entire Document): Reject S UBMITTER: William R. Gee, Jr . , Potomac Electr ic Power Company COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Proposed action. Withdraw proposed Standard NFPA 85H. SUBSTANTIATION: I. In general, the proposed standard is vague and ambiguous which wi l l resul t in broad interpretat ions and potential confusion.

2. The proposed standard deals more with unit operation and design but does not address actual f i r e protection systems or procedures. I t is therefore of l i t t l e value as a standard.

3. Atmospheric f lu id ized bed combustion actual ly consists of two basic technologies which have s igni f icant differences in many of the i r main systems. An example here would be the need to address the d i f fe ren t hazards of a c i rcu lat ing and bubbling bed fuel handling system. This documents does not address major areas of s ign i f icant differences between the technology.

4. At this point in time, the f lu id ized bed technology is s t i l l emerging with demonstration units currently resolving operating and design problems. The equipment manufacturers may not have developed s ign i f icant operating data to determine the most appropriate philosophy as i t relates to explosion hazards. Introduction of a standard now could unfa i r ly l im i t the equipment manufacturer and impede the progress of the technology. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The Committee believes this document is a good s tar t . The information contained in here is most useful and is already being used in some cases. The purpose of the document is to prescribe methods for the safe operation of bo i ler equipment, as is stated in the scope of this Committee.

The Committee also notes that the dif ference between bubbling bed and c i rcu lat ing bed systems is noted in the document. As time and experience with this technology increases, the Committee, as do a l l NFPA Technical Committees, wi l l be so l i c i t i ng public proposals to update the document to re f l ec t the "lessons learned" from this equipment.

(Log #56) 85H- 2 - (Entire Document : Reject SUBMITTER: Huberto R. Platz, Wisconsin Electr ic Power Company COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: The stated purpose of the standard ". . . is to establish minimum requirements for the design, i ns ta l l a t i on and operation of atmospheric f lu id ized bed system boi lers, the i r fuel preparation and burning systems, and related control equipment, to contribute to operating safety, and to prevent combustion hazards".

When viewed in the context of establishing only "minimum rquirements", the document has accomplished i ts purpose. Rea l is t i ca l l y , due to the diverse and dynamic state of current atmospheric f lu id ized bed comhustlon (AFBC) system design, i t is d i f f i c u l t to establish standards which are anythinq but vague and general.

Therefore, consideration should be given to changing the t i t l e of this document from a standard to that of a guideline. Having recently completed the process of preparing specif icat ions and evaluating bids for u t i l i t y sized AFBC boi lers. Wisconsin Electr ic (WE) recognizes the value of such a document. Having seen proposals from several of the major boi ler vendors, WE also recognizes the potential need to deviate from some of the requirements established in this document. Addi t ional ly, there are design areas of concern that have been omitted which require guidelines and fur ther c1ar l f lcat ion.

For example, paragraph 4-1.2.2 addresses fuel burning system design. Under (c)4. i t states "a bed feed that operates at a lower pressure than the boi ler furnace enclosure to which i t is connected shall have a lock hopper or other suitable means to prevent back flow of combustion products." What is meant by "other suitable means"? Would a head of sol id fuel sat is fy the intent?

Nowhere in this section is there mention of feeder design requirements when the bed feed system operates at bo i ler furnace pressure. Also in this case, what is needed to prevent back flow of combustion products into the sol id fuel storage system?

Paragraph 4- I .2.2(c)3, requires that "Fuel piping to and from feeders shall be designed for free flow within the range of sol id fuel size and moisture content". This is an excellent point considering AFBC units often store and feed re la t i ve l y moist and f ine ly sized materials. However, storage s i lo design should also be addressed.

Conversely, paragraph 4- I .2.2(a)3, requires "Observation ports shall be provided to permit inspection of the furnace and burners". Aside from giving tour groups something to look at, most observation ports in AFBC units provide l i t t l e benefit, and are sources for f lue gas leakage.

Paragraph 5-1.4.3 requires that "A posit ive means shall be provided to prevent fuel leakage into idle beds". What is meant by a posi t ive means? Several operating units have had problems keeping mechanical devices operable under the severe conditions of a f lu id ized bed. The slumped bed material, by i t s e l f , is usually an e f fec t ive seal, but may not qual i fy under this de f in i t ion .

In summary, the document contains many areas which require in terpretat ion, and others which may not be pract ical . To c lass i fy i t as a standard would be premature and not in the best in terest of the industry. SUBSTANTIATION: Document should be a guideline, not a standard. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: See Committee Action on Comment 85H-I (Log #41).

(Log #55) 85H- 3 - (Entire Document): Reject S_VBMITTER: K. M. Gi l lespie, Georgia Power Company/EEl COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: In a l l affected paragraphs change the word "shal l " to "should." SUBSTANTIATION: The word "shal l " is used 190 times in this standard. The use of the word "shal l " s ign i f i can t l y reduces the a b i l i t y of the owner to use good judgement to design and operate a boi ler in the most economical manner while maintaining essential l i f e safety considerations.

Should insurance or state regulatory agencies enforce this standard, the owner discret ion allowed in paragraph I-3 is eliminated.

We recommend using the format of NFPA 851, which has also been issued for comment. 85I minimizes the use of the word "shal l " by replacing i t with "should." COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: See Committee Action on Comment 85H-I (Log #41).

(Log #8) 85N- 4 - (1-1 and 1-1 .1 ) : Accept in P r i nc i p l e SUBMITTER: Courtney D. Alvey, L u t h e r v i l l e , MD COHMENT ON PROPOSAL NO.: 85H-1 RECOMMENDATION: Add new sect ions as f o l l ows :

1-1 Scope. I -1 .1 This standard app l ies to b o i l e r s wi th fue l

input greater than 12,500,000 ( ? ) Btuh (3663 kw). This standard applies only to boi ler-furnaces using atmospheric f lu id ized beds f i r i n g coal or alternate sol id fuels. SUBSTANTIATION: Chapter is t i t l e d "Purpose and Scope," but no scope statements are included. Even i f i t is the Committee's intent to cover a l l sizes, down to and including " res ident ia l " sizes, i f such are l i ke l y to be bu i l t , then this should be stated. COMMITTEE ACTI~: Accept in Principle.

Change f i r s t sentence to read: "This standard applies to boi lers with a fuel input

rat ing of 12,500,000 Btuh (3663 kW) or greater." Delete the word "so l id" from the second sentence.

COMMITTEE STATEMENT: These units can use other than solid fuel .

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(Log #9) 85H- 5 - ( l - I thru I -4) : Accept in Principle SUBMITTER: Courtney D. Alvey, Lutherv i l le , MD COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Change numbers, add t i t l e , and new sections as follows:

I-2 Purpose. I-2.1 (same as current l - l ) . I-2.2 (Add section same as section I-2.2 in 85B, D,

and E) I-2.3 (Same as current 1-2). I-2.4 (Add section same as section I-2.4 in 85B, D,

and E). I-2.5 (Same as current I -3) . I-2.6 (Same as current I -4) .

S~BSTANTIATION: There is no reason this standard for AFB units should not include the same statements of purpose that are in 85B, D, and E. COMMITTEE ACTION: Accept in Principle.

Delete Sections I-3 and I-4 and change Section I-2 as shown:

I-2 Purpose. l -Z . l The purpose of this standard is to establish

minimum requirements for the design, ins ta l la t ion and operation of atmospheric f lu id ized bed system boi lers, the i r fuel preparation and burning systems, and related control equipment, to contribute to operating safety. and to prevent combustion hazards.

I-2.2 No standard can be promulgated which wi l l guarantee the elimination of gas-f ired boi ler-furnace explosions. Technology in this area is under constant development which wi l l be ref lected in revisions to this standard. The user of this standard must recognize the complexity of fuel f i r i n g as to the type of equipment and the character ist ics of the fuel . Therefore, the designer is cautioned that the standard is not a design handbook. The standard does not do away with the need for the engineer or competent engineering judgment. I t is intended that a designer capable of applying more complete and rigorous analysis to special or unusual problems shall have la t i tude in the development of such designs. In such cases, the designer is responsible for demonstrating the va l i d i t y of the approach.

I-2.3 This standard is applicable to new ins ta l la t ion and to major a l terat ions or extensions of exist ing equipment contracted for subsequent to December, 1988. This standard is not retroact ive.

I-2.4 Furnaces such os those of process heaters used in chemical and petroleum manufacture, wherein steam generation is incident ia l to the operation of a processing system, are not covered by this standard.

1-2.5 Because this standard is based upon the present state of the ar t , application to exist ing ins ta l la t ions is not mandatory. Nevertheless, operating companies are encouraged to adopt those features of this standard that are considered applicable and reasonable for exist ing ins ta l la t ions.

I-2.6 Emphasis is placed upon the importance of combustion control equipment, safety inter locks, alarms, t r ips and other related controls that are essential to proper bo i ler operation. COMMITTEE STATEMENT: The changes made by the Committee wi l l add c la r i t y to this subsection.

(Log #I) 85H- G - ( I -5 (New)): Accept S UBMITTER: Robert P. Richmond, Baton Rouge, LA COMMENT ON PROPOSAL NO.: 85H-I RECOMMEN_ DATION: Add a new paragraph I-5 to read:

"FIuidized Bed Combustion Systems such as the regenerators of f l u id cata ly t ic cracking units used ill chemical and petroleum manufacture, wherein steam generation is incidental to the operation of a processing system, are not covered by this standard." SUBSTANTIATION: Similar exclusionary statements are contained in each of the other NFPA 85 Boiler-Furnace Explosion standards. Such a statement is par t icu lar ly relevant to this standard because of the widespread existence of such units in the petroleum industry. COMMITTEE ACTION: Accept. COMMITTEE STATEMENT: Make this paragraph 1-3 instead of I-5 to conform with Comment 85H-5 (Log #9).

(Log #57) 85H- 7 - (Chapter Z): Reject SUBMITTER: Martin M. Cot t re l l , Allenton, PA COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Def in i t ions should include:

Bed Feed. The combination of fue l , sorbent and bed recycle mater ia l . " SUBSTANTIATION: C la r i f i es material inventory included in the term which is used throughout the document. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The Committee believes this word is se l f defining and therefore, a separate def in i t ion is not necessary.

(Log #49) 85H- 8 - (Chapter 2): Reject ~UBMITTER: Nell Raskin/3ose Martines-Lara, Pyropower Corporation COMMENT ON PROPOSAL NO~: 85H-I RECOMMENDATION: Revise as follows:

Lance. A burner providing fuel input d i rec t ly into the bed which does not have a flame safety device. ~UBSTANTIATION: Some of the units may be designed with additional a i r flowing thru the lances. The only dif ference between a Bed Burner and a lance is the flame safety device. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The Committee believes this proposed def in i t ion is design specif ic and therefore, should not be a part of a de f in i t ion .

(Log #47) 85H- 9 - (Chapter 2): Reject SUBMITTER: Neil Raskin/Joe Martinez-Lara, Pyropower Corporation COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Revise as follows:

Primary a i r . In a c i rcu lat ing bed, that portion of total a i r introduced at the base of the combustor through the a i r d i s t r i bu to r or side ports. SUBSTANTIATION: Some of the present un i t 's side ports are used for additional primary a i r . COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The Committee believes that the de f in i t ion of secondary a i r as well as the exist ing def in i t ion of primary a i r are su f f i c ien t to describe this term.

(Log #I0) 85H- lO - (Chapter 2 And Chapter 3): Accept in Principle SUBMITTER: Courtney D. Alvey, Lutherv i l le , MD COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Add def in i t ions , to be the same as in 85E for the fol lowing:

Air/Fuel Ratio; Air-Rich; Fuel-Rich; Excess Air; Theoretical Air; Alarm; Annunciator; Approved; Authority Having Jur isd ic t ion; Boi ler; Boi ler Control System; Boler Furnace Enclosure Coal; Combustion Control System; Flame Detector; Flame Envelope; Inter lock; Labeled; Listed; LP Gas; Master Fuel Trip; Natural Gas; Prove; Purge; Purge Rate; Set Point; Shall; Should; Unit; Unit Purge.

Also, interchange Chapters 2 and 3, and renumber a l l sections of current Chapter 3 to re f lec t the change. SUBSTANTIATION: 85H should have at least a l l of these terms defined. Ed i to r ia l l y , i t might be easier to l i f t a l l def in i t ions from 85E, even though some are not used in H. Also, for ed i to r ia l consistency, def in i t ions should be Chapter 3 and General should be Chapter 2. COMMITTEE ACTION: Accept in Principle.

Switch Chapters 2 and 3 a f te r adding the fol lowing to the def in i t ions currently in Chapter 2:

Air Fuel Ratio. Air-Rich. A rat io of a i r to fuel supplied to a

furnace which provides more a i r than that required for an optimum a i r / f ue l ra t io .

Fuel-Rich. A rat io of a i r to fuel supplied to a furnace which provides less a i r than that required for an optimum a i r / fue l ra t io .

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Excess Air. Air supplied for combustion in excess of theoretical air .

NOTE: This is not "Air rich" as previously defined. Theoretical Air (Stoichiometric Air) . The

chemically correct amount of a i r required for complete combustion of a given quantity of a specific fuel.

Alarm. An audible or v is ible signal indicating an off-standard or abnormal condition.

Annunciator. A device which indicates an off-standard or abnormal condition by both visual and audible signals.

Approved. Acceptable to the "authority having jur isdict ion."

NOTE: The National Fire Protection Association does not approve, inspect or cert i fy any instal lat ions, procedures, equipment, or materials nor does i t approve or evaluate testing laboratories. In determining the acceptabil ity of instal lat ions or procedures, equipment or materials, the authorit~ having Jurisdiction may base acceptance on compliance with NFPA or other appropriate standards. In the absence of such standards, said authority may require evidence of proper insta l lat ion, procedure or use. The authority having Jurisdiction may also refer to the l ist ings or labeling practices of an organization concerned with product evaluations which is in a position to determine compliance with appropriate standards for the current production of l isted items.

Authority Having Jurisdiction. The "authority having jur isdict ion" is the organization, off ice or individual responsible for "approwng" equipment, an instal lat ion or a procedure.

NOTE: The phrase "authority having Jurisdiction" is used in NFPA documents in a broad manner since jur isdict ions and "approval" agencies vary as do their responsibi l i t ies. Where public safety is primary, the "authority having jur isdict ion" may be a federal, state, local or other regional department or individual such as a f i re chief, f i re marshal, chief of a f i re prevention bureau, labor department, health department, building o f f i c ia l , electr ical inspector, or others having statutory authority. For insurance purposes, an insurance inspection department, rating bureau, or other insurance company representative may be the "authority having jur isd ic t ion. " In many circumstances the property owner or his designated agent assumes the role of the "authority having jur isdict ion"; at government instal lat ions, the commanding off icer or departmental o f f ic ia l may be the "authority having jur isd ic t ion."

Boiler. A closed vessel in which water is heated, steam is generated, steam is superheated, or any combination thereof, by the application of heat from combustible fuels, in a self-contained or attached furnace.

Boiler Control System. The group of control systems which regulates the boi ler process including the Combustion Control but not the Burner Management.

Boiler-Furnace Enclosure. The physical boundary for al l boi ler pressure parts and the combustion process.

Coal. The general name for the natural rocklike, brown to black derivative of forest-type plant material. By subsequent underground geological processes, this organic material is progressively compressed and indurated, f i na l l y alter ing into graphite and graphite-l ike material. Coal contains carbon, hydrogen, oxygen, nitrogen and sulphur, as well as inorganic constituents which form ash after burning. There is no standard coal, but an almost endless variety as to character and composition. Starting with l ign i te (brown coal) at one extreme, the other basic classifications are subbituminous, bituminous and anthracite. [For greater detai l , see ASTM D388-66(1972) - Standard Specifications for Classification of Coals by Rank.]

Combustion Control System. The control system which regulates the furnace fuel and a i r inputs to maintain air / fuel rat io within the l imits required for continuous combustion and stable flame throughout the operating range of the boi ler in accordance with demand. This control system includes the furnace draft control where applicable.

Flame Detector. A device which senses the presence or absence of flame and provides a usable signal.

Flame Envelope. The confines (not necessarily v i s i b l e ) of an independent process convert ing fuel and a i r in to products of combustion.

I n te r l ock . A device or group of devices arranged to sense a l i m i t or o f f - l i m i t condi t ion or improper sequence of events and to shut down the of fending or re la ted piece of equipment, or to prevent proceeding in an improper sequence in order to avoid a hazardous cond i t ion .

Labeled. Equipment or mater ia ls to which has been attached a label, symbol or other identifying mark of an organization acceptable to the "authority having Jurisdiction" and concerned with product evaluation, that maintains periodic inspection of production of labeled equipment or materials and by whose labeling the manufacturer indicates compliance with appropriate standards or performance in a specified manner.

Listed. Equipment or materials included in a l i s t published by an organization acceptable to the "authority having Jurisdiction" and concerned with product evaluation, that maintains periodic inspection of production of l lsted equipment or materials and whose l i s t ing states either that the equipment or material meets appropriate standards or has been tested and found suitable for use in a specified manner.

NOTE: The means for identifying l isted equipment may vary for each organization concerned with product evaluation, some of which do not recognize equipment as l isted unless i t is also labeled. The "authority having Jurisdiction" should u t i l i ze the system employed by the l i s t ing organization to identi fy a l isted product.

LP-Gas. A material composed predominantly of any of the followlng hydrocarbons or mixtures of them: propane, propylene, normal butane, isobutane and butylenes.

Master Fuel Trip. An event resulting in the rapid shutoff of al l fuel, including igniters.

Natural Gas. A gaseous fuel occurring in nature consisting mostly of a mixture of organic compounds (normally methane, ethane, propane and butane). The Btu value of natural gases varies between 700 and 1500 Btu per c u f t (26.1 and 55.9 M,]/m3), th~ majority averaging 1000 Btu per c u f t (37.3 M~/m ).

Prove. To establlsh by measurement or test the existence of a specified condition, such as flame, level, flow, pressure or position.

Purge. A flow of a i r through the furnace, boiler gas passages and associated f lues and ducts which w i l l e f f e c t i v e l y remove any gaseous combustibles and replace with a i r . Purging may also be accomplished by an ine r t medium.

Purge Rate. A constant f low of not less than 25 percent nor more than 40 percent of the f u l l load vo lumetr ic a i r f low at the po in t of measurement.

Set Point . A predetermined value to which an instrument is adjusted and at which i t shall perform its intended function.

Shall. Indicates a mandatory requirement. Should. Indicates a recommendation or that which is

advised but not required. Unit. The confined space of the furnace and the

associated boi ler passes, ducts and fans which convey the gases of combustion to the stack.

Unit Purge. A flow of a i r at purge rate through the unit from the forced draft (FD) fan to the stack for the greater of either: (1) a period of not less than f ive minutes; or (2) f ive changes in volume of the boiler-furnace enclosure. COMHITT~ STATEMENT: Definitions have been added as indicated by the submitter.

(Log #51) 85H- 11 - (2-2 (New) and 4-4.1 (New)): Accept in Principle SUBMITTER: H. D. Ege, Jr. , Kansas City, MO COMMENT QN PROPOSAL NO.: 85H-I RECOMMENDATION: Add new paragraphs as follows:

2-2 Manufacturing, Design and Engineering. 2-2.4 This standard requires a minimum degree of

automation (6-1.2). The trend toward more complex plants or increased automation requires added provisions for:

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(a) Information about significant operating events permitting the operator to make rapid evaluation of the operating situation. The operator shall be provided with continuous and usable displays of cr i t ica l trends which wi l l indicate conditions that may lead to unsafe operation.

2-4.2 Furnace explosions have occurred as a result of unfavorable functional design. Frequently, the investigation has revealed human error, and has completely overlooked the chain of causes which triggered the operating error. Therefore, the design, installation and functional objectives of the overall system of components and their controls shall be integrated. Consideration shall be given to the human-machine relationships which wi l l exist during the operating l i f e of the system.

4-4.1 Continuous simultaneous trend display of boiler output, feedwater flow rate, total fuel flow rate, total air flow rate as a percentage of maximum unit load, drum level, final steam temperature, main steam pressure and furnace draft shall be provided at the operating location (see 2-2.4, 2-4.2 and 2-4.4). SUBSTANTIATION: None. COMMITTEE ACTION: Accept in Principle.

Change the following paragraph as noted: 2-2 Manufacturing Design and Engineering. 2-2.4 This standard requires a minimum degree of

automation (6-I.2). The trend toward more complex plants or increased automation requires added provisions for:

Information about significant operating events permitting the operator to make rapid evaluation of the operating situation. The operator shall have available continuous and usable displays of cr i t ical trends which wil l indicate conditions that may lead to unsafe operation.

2-4.2 Furnace explosions have occurred as a result of unfavorable functional design. Frequently, the investigation has revealed human error, and has completely overlooked the chain of causes which triggered the operating error. Therefore, the design, installation and functional objectives of the overall system of components and their controls shall be integrated. Consideration shall be given to the human-machine relationships which wi l l exist during the operating l i f e of the system.

4-4.1 Continuous simultaneous trend display of boiler output, feedwater flow rate, total fuel flow rate, total a i r flow rate as a percentage of maximum unit load, drum level, final steam temperature, main steam pressure and furnace draft shall be available at the operating location (see 2-2.4, 2-4.2 and 2-4.4). COMMITTEE STATEMENT: The Committee believes the change to the word "provided" is appropriate because i t may not always be necessary to have this information always in sight, but at least to have access to i t .

Note that Chapter 3 is now Chapter 2 according to 85H-I0 (Log #I0).

(Log #42) 85H- 12 - (3-1.1): Reject SUBMITTER: William R. Gee, Jr., Potomac Electric Power Company COMMENT ON PROPOSAL NO.: 85H-1 RECOMMENd: Change the word "wi l l " in the f i rs t sentence to "could". SUBSTANTIATION: As written, the sentence implies that there wil l always be a rapid or uncontrolled combustion when a dangerous combustible mixture is present with an ignition source. There may not always be rapid combustion under these conditions. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: I f this condition does not occur there is no danger. I f the condition does occur there wil l be danger and a problem imminent.

(Log #11) 85H- 13 - (3-1.1 and 3-1.2): Accept SUBMITTER: Courtney D. Alvey, Lutherville, MD COMMENT ON PROPOSAL NO.: 8511-I RECOMMENDATION: Relocate last two sentences of 3-1.1 (beginning with "The magnitude and intensity. . .") to follow existing 3-I.2 sentence.

SUBSTANTIATION: When order of these two sections was reversed (compared to B, D, and E) to put greater emphasis on "combustion hazards" rather than "explosions," these sentences appeared to logically follow the statement of the basic cause of furnace explosions. COMMITTEE ACTION: Accept. COMMITTEE STATEMENT: Note that this is now Chapter 2.

(Log #43) 85H- 14 - (3-1.5): Reject _~_VBMITTER: William R. Gee, Jr., Potomac Electric Power Company COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Delete text. }UBSTANTIATION: This statement is speculative and does not address corrective actions. This issue should be a design consideration for the manufacturer. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: This is informative in nature to help describe some of the potential dangers with the enclosure and is therefore appropriate.

(Log #12) 85H- 15 - (3-2.1): Accept ~UBMITTER: Courtney D. Alvey, Lutherville, MD COMMENT ON P R O P ~ : 85H-I R__~OMMENDATION: Change "his/her" to "the purchaser's." SUBSTANTIATION: Editorial. COMMITTEE ACTION: Accept. COMMITTEE STATEMENT: Note that this is now Chapter 2.

(Log #48) 85H- 16 - (3-2.2): Reject ~BMITTER: Nell Raskin/Jose Martinez Lara, Pyropower Corporation COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Paragraph needs more explanation on how to accomplish this. SUBSTANTIATION: None. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: No specific wording has been recommended by the commenter nor was there is a reason for this change. The Committee also notes that this is not a design manual and the designer must be able to accomplish this requirement.

(Log #13) 85H- 17 - (3-2.4(a) Note (New)): Accept in Principle SUBMITTER: Courtney D. Alvey, Lutherville, MD COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Add note:

NOTE: The designer shall consider providing the operator with continuous and useable trend displays of cr i t ical parameters which wil l permit safe operation during adverse conditions and maintain continuity between man and machine.

SUBSTANTIATION: To give guidance as to what kind of "information" should be provided, consistent with proposed additions to B and D. COMMITTEE ACTION: Accept in Principle. COMMITTEE STATEMENT: The Committee believes the note is helpful but that Section 3-2 already covers the concern.

(Log #14) 85H- 18 - (3-3.1(c)): Accept SUBMITTER: Courtney D. Alvey, Lutherville, MD COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Revise as follows:

"The safety interlock system and protective devices shall be jo in t ly tested and checked out by the organization with the system design responsibility and these who operate and maintain such system and devices during normal operating l i f e of the plant. These tests shall be accomplished before in i t ia l operation."

33

SUBSTANTIATION: Edi tor ia l - to be consistent with revised B & D. COMMITTEE ACTION: Accept. COMMITTEE STATEMENT: Note that this is now Chapter 2.

(Log #15) 85H- 19 - (3-6.1(b)): Accept SUBMITTER: Courtney D. Alvey, Lutherv i l le , MD COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: In second sentence, change "stop" to " in te r rup t . " SUBSTANTIATION: Edi tor ia l - to be consistent with revised B & D. COMMITTEE ACTION: Accept. COMMITTEE STATEMENT: Note that this is now Chapter 2.

(Log #44) 85H- 20 - (3-7): Reject SUBMITTER: William R. Gee, Jr . , Potomac Electr ic Power Company COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Delete ent i re section.

Withdraw proposed Standard NFPA 85H. SUBSTANTIATIQ.N: Section 3-7, Special Problems, does in fact highl ight problems of coal f i red units but i t makes no recommendations on how to resolve them except that the problems should be addressed during design. Since solving these problems becomes the responsib i l i ty of the manufacturer and no guidelines or recommendations are present, the ent i re section should be deleted.

As writ ten, this material would be appropriate as a guideline but not a standard. COHHITTEE ACTION: Reject. COMMITTEE STATEMENT: See Committee Action on Comment 85H-I (Log #41).

(Log #58) 85H- 21 - (3-7.3(c)) : Reject SUBMITTER: Martin M. Cot t re l l , Allentown, PA COMMENT ON PROPOSAL NO,: 85H-1 RE~MMENDATION: Revise paragraph to add at end of last section:

" . . . a n d f u r n a c e p r e s s u r e e x c u r s i o n s . "

SUBSTANTIATION: Furnace pressure excursions wi l l be the resultant of Fuel flow disturbances and help explain basis for section. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The Committee does not believe that the raw coal feed is related to furnace pressure excursions.

(Log #16) 85H- 22 - (4- I .2 .2(a)3) : Reject SUBM_ITTER: Courtney D. Alvey, Lutherv i l le , MD CgMUENT_ ON PRO P9 SA LyO~ : 85H-I RECOMMENDATION: Change "burners" to "warm-up burners . " SUBS!ANTIAT]ON: E d i t o r i a l . Warm-up burners are the only "burners" on t h i s type u n i t . Using j u s t the word "burners" might imply the beds. I t may not be poss ib le on a la rge un i t to prov ide v isua l observa t ion of a l l beds. COMMITTEE ACTION: Reject . COMMITTEE STATEMENT: The Committee notes that t h i s sect ion app l ies to a l l burners and not j u s t warm up I)urners.

(Log #59) 85H- 23 - (4- I .2 .2(b)2) : Accept SUBMITTER: Martin M. Cot t re l l , Allentown, PA COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Revise l ine three to add:

" . . . water, fuel and bed mater ia l . " SUBSTANTIATION: Backshifting of bed material into the f lu id iz ing a i r plenum should be minimized. COMMITTEE ACT~: Accept.

(Log #17) 85H- 24 - (4-1.2.2(c)3): Accept SUBNITTER: Courtney D. Alvey, Lutherv i l le , MD COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: In f i r s t sentence, change "coal" to " fue l . " SUBSTANTIATION: Ed i tor ia l . Consistency with rest of paragraph. COMMITTEE ACTION: Accept.

(Log #24) 85H- 25 - (4-1.2.2(c)5): Accept in Principle ~UBMITTER: William Cunningham, Riley Stoker Corp. COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Delete text :

5. Means shall be provided to assure adequate transport a i r for the required fuel input, only when required by the manufacturer. SUBSTANTIATION: All manufacturer's may not require transport a i r , therefore a note should be added "only when required." COMMITTEE ACTION: Accept in Principle.

Change to read: I f transport a i r is required, a means shall be

provided to assure a supply that is adequate for the required fuel input. COMMITTEE STATEMENT: The intent of the submitter wi l l be sat is f ied with this wording.

(Log #52) 85H- 26 - (4-1.2.2(d) I ) : Reject ~UBMITTER: H. D. Ege, Jr . , Kansas City, MO COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: The fol lowing comment is proposed:

"Where coal or similar fuels of low v o l a t i l i t y with a history of no spontaneous ign i t ion or explosion hazards ae to be used exclusively in the f a c i l i t y , f ixed f i r e protection is not required."

Most anthracite coals, anthracite culm and petroleum cokes would f i t this category. SUBSTANTIATION: None. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The standard has no requirement for any f ixed f i r e protection systems for any type of fuel .

(Log #18) 85H- 27 - (4-1.2.2(d)2): Accept SUBMITTER: Courtney D. Alvey, Lutherv i l le , MD COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Delete f i r s t sentence and change second sentence as follows:

"The transport a l r fans, ducts, and dampers shall be ,i

SUBSTANTIATION: Ed i tor ia l . "Transport a i r " is defined in Chapter 2 and does not need to be repeated here. COMMITTEE ACTION: Accept.

(Log #53) 85H- 28 - ( 4 - 1 . 2 . 2 ( d ) 3 ) : Reject SUBNITTER: H. D. Ege, J r . , Kansas C i ty , MO COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: The f o l l o w i n g comment is proposed:

"Bed feed lock hoppers and pressure feeders shal l be equipped wi th high temperature alarms, high pressure alarms where app rop r ia te , and feed t r i p s as a backup f o r f a i l u r e or leakage of the f i n a l c losure element." SUBSTANTIATION: One of the commonest f a i l u r e s of feed systems is f o r the f i n a l gate to c lose, or at l eas t , to close t i g h t enough to prevent backf low of hot furnace gasses in to the feed system. Since most of the c i r c u l a t i n g f l u i d bed systems are o f f e red as pressur ized systems, p o s i t i v e i n t e r l o c k s to prevent f lashback in to feed systems should be mandatory. COMMITTEE ACTION: Reject . COMMITTEE STATEMENT: The Committee does not be l ieve that those alarms are necessary.

34

(Log #25) 85H- 29 - (4-1.2.2(d)4): Reject SUBMITTER: William Cunningham, Riley Stoker Corp. COMMENT ON PROPOSAL NO.: 85H-l RECOMMENDATION: Revise as follows:

4. Means shall be provided to control crusher out let temperature within l imi ts suitable for the fuel being f i red ( i f required by the manufacturer). SUBSTANTIATION: Include " i f required by the manufacturer." COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: This is required at any temperature. I f the crusher can be operated at any range of temperatures, than i t complies. Also, Section 4-I .2.2(d) heading already notes that this applies to these si tuat ions involving crusher subsystems.

(Log #60) 85H- 30 - (4 - l .2 .2 (h ) ) : Reject SUBMITTER: Martin M. Cot t re l l , Allentown, PA COMMENT ON PROPOSAL NO.: 85H-1 RECOMMENDATION: Flyash co l lec t in 9 equipment is not addressed in the document, par t i cu la r ly in the context that the ash could have a s ign i f i can t ly higher carbon content in some units than is found in pulverized coal units. We have no specif ic wording to propose other than to raise the question. SUBSTANTIATION: Uncertain as to intent to include them. ~ M M I T T ~ N : Reject. COMMITTEE STATEMENT: This is beyond the scope of the document as i t currently stands. The Committee would be interested in having specif ic recommendations from the commenter for the next revision to the standard.

(Log #61) 85H- 31 - (4-1.2.2(h) I ) : Reject SUBMITTER: Martin M. Cot t re l l , Allentown, PA COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Revise l ine 4 to add:

" . . . fuel burning process and sorbent ash generation during unit operation." SUBSTANTIATION: Total volume of ash must be removed. Adequate sizing of these systems has been a problem on some units. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The additional words that have been proposed do not add to the requirement. The current wording is su f f i c ien t to cover the submitters concern because i t covers the sorbent ash generation process.

(Log #62) B5H- 32 - (4- I .2 .2(h)3) : Accept SUBMITTER: Martin M. Cot t re l l , Allentown, PA COMMENT ON PROPOSAL NO. : 85H-I RECOMMENDATION: Revise l ine 5 to add:

" . . . cooling medium flow and material discharge , i

SUBSTANTIATI~: Since water and a i r are now used for cooling a more generic term is appropriate. Experience indicates circumstances where monitoring of both cooling medium and material discharge temperature is appropriate to assure material is cool enough to prevent damage to transport system and prevent possible Fire in ash storage f a c i l i t y . COMMITTEE ACTION: Accept.

(Log #65) 85H- 33 - (4 -1 .2 .2 ( i ) I ) : Reject SUBMITTER: Martin M. Cot t re l l , Allentown, PA COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Revise l ine 4 to add:

" . . . the fuel burning process and sorbent ash generation. . ." SUBSTANTIATION: Total volume of ash should be addressed. COMMITTEE ACTION: Reject.

COMMITTEE STATEMENT: See Committee Action on Comment 85H-31 (Log #61).

(Log #19) 85H- 34 - (4-2.1.2, 4-2.2(b)): Accept SUBMITTER: Courtney D. Alvey, Lutherv i l le , MD COMMENT ON PROPOSAL NO.: 85H-l RECOMMENDATION: Change "mixture" to " ra t io " in both places. SUBSTANTIATION: Edi tor ia l - Consistency with B, D, and E. "Mixture" is not as de f in i t i ve as "a i r / fue l ra t i o . " Par t icu lar ly in 4-2.2(b), maintaining the "mixture" within l imi ts could imply simply keeping the bed physical dimensions within some par t icu lar space in the furnace. COMMITTEE ACTION: Accept.

(Log #34) 85H- 35 - (4-2.2(c)) : Reject SUBMITTER: R. Shoemaker, American Electr ic Power COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: The last sentence "These minimum and maximum l imi ts shall be defined by the boi ler manufacturer and ver i f i ed by operating tests [see 4 - I . 2 . 2 ( f ) I ] . " implies the fuel and a i r wi l l be operated at the minimum and maximum l imi ts during test runs, Place a period a f te r the word "manufacturer" and delete rest of sentence.

The reference "[See 4 -1 .2 .2 ( f ) I ] " is incorrect, since i t about fuel supply piping for lances. SUBSTANTIATION: Fossil fuel units are not operated at l imi ts or near l imi ts of combustion s t ab i l i t y on purpose or during normal operating tests. The boi ler manufacturer should ve r i f y by tests the recommended l imi ts are safe and conservative at some test f a c i l i t y .

Open loop control system simulations can be run to ve r i f y the l imits operate as designed. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The Committee believes that these operational tests are important and necessary to assure safe operation.

(Log #3) 85H- 36 - (4-2.2(c)) : Accept SUBMITTER: Dale E. Dressel, Monsanto Company COMMENT ON PROPOSAL NO.: 85H-l RECOMMENDATION: Change reference at end of paragraph from "See 4 -1 .2 .2 ( f ) I . " to:

"See 4 - I . 2 .2 (e ) I . " SUBSTANTIATION: Incorrect reference is given. COMMITTEE ACTION: Accept.

Edi tor ia l Note: Change heading of 4- I .2.2(e) to "Bed Feed Systems".

Also, the reference is 4-1.2.2(e).

(Log #63) 85H- 37 - ( 4 - 2 . 2 ( c ) ) : Re jec t SUBMITTER: M a r t i n M. C o t t r e l l , A l l en town , PA COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Revise l i n e 5 to add:

" . . . system in e i t h e r au tomat i c o r manual mode," SUBSTANTIATIO_N: Exper ience i n d i c a t e s t h a t these requ i rements should be c l e a r . COMMITTEE ACTION: Re jec t . COMMITTEE STATEMENT: The Committee believes this would make the requirement too res t r i c t i ve .

(Log #20) 85H- 38 - (4 -2 .2 ( I ) ) : Accept SUBMITTER: Courtney D. Alvey, Lutherv i l le , MD COMMENT ON PROPOSAL NO.: 85H-1

I RECOMMENDATION: Change: "Solid fuel flow devices on each feeder are recommended" to:

"Consideration shall be given to providing solid fuel flow devices on each feeder."

35

SUBSTAN_T~: Editor ial - NFPA Style Manual. COMMITTEE ACTION: Accept.

(Log #35) 85H- 39 - (4-3.1.I(a)): Accept in Principle SUBMITTER: R. Shoemaker, American Electr ic Power COMMENT ON PROPOSAL NO.: 85H-l RECOMMENDATION: The second sentence "The indication of any bed temperature shall be used for monitoring and interlocking" implies that a l l bed temperature indications have dual functions and must be used in interlock scheme. Sentence probably should read:

"Any bed temperature measurement used for interlocking shall be displayed." SUBSTANTIATION: Not compatible with 6-2.3( i) . COMMITTEE ACTION: Accept in Principle.

Change the second sentence to read: "Such bed temperature used for monitoring and

interlocking shall be made avai lable." COMMITTEE STATEMENT: The proposed change by the Committee should satisfy the intent of the submitter.

(Log #4) 85H- 40 - (4-3.1. I(c)) : Accept SUBMITTER: Dale E. Dressel, Monsanto Company COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Change reference at end of paragraph from "(see paragraph 5-2.1.1)." to "(see paragraph 5-2.5.1)." ~BSTANTIATION: Incorrect reference is given. COMMITTEE ACTION: Accept.

(Log #45) 85H- 41 - (Chapter 5): Reject SUBMITTER: William R. Gee, 3r., Potomac Electr ic Power Company COMMENT ON PROPOSAL NO.: 85H-l RECOMMENDATI~: Delete entire chapter. Withdraw proposed standard NFPA 85H. SUBSTANTIATION: l . In general, i t should be the equipment manufacturer's responsibi l i ty to define operational requirements. Making start-up and operating procedures a part of a standard l imits the equipment manufacturer unfair ly.

2. Currently, equipment manufacturers are attempting to demonstrate this technology. On the two u t i l i t y -s i zed units in service, major equipment failures have occurred in the start-up process. This may indicate that insuf f ic ient data exists at this time to determine the most appropriate procedures on units of this size. General guidelines would be appropriate but not a standard. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: See Committee Action on Comment 85H-I (Log #41).

(Log #4A) 85H- 42 - (5-I .2): Accept SUBMITTER: Dale E. Dressel, Monsanto Company COMMENT ON PROPOSAL NO.: 85H-I R E C Q M _ M ~ : Change the f i r s t sentence from:

"The sequences are based on the typical fuel supply system shown in Figure l . "

To: "The sequences are based on the typical safety

interlock system shown in Figure l . " SUBSTANTIATION: Figure l is currently incorrectly referenced as a fuel supply system diagram in this section. COMMITTEE ACTION: Accept.

(Log #27) 85H- 43 - (5-1.3): Accept in Principle S~LBMITTER: William Cunningham, Riley Stoker Corporation COMMENT ON PROPOSAL NO.: 85H-l RECOMMENDATION: Revised text:

" a i r flow may be reduced below the purge value,"

SUBSTANTIATION: This appears to be in confl ict with paragraph 5-2.5.1.2(f), which is a mandatory MFT. COMMITTEE ACTION: Accept in Principle.

Make the following changes: I. Delete 5-2.5.1.2(f) in i ts entirety and renumber

the remaining subparagraphs. 2. In 5-2.1.2(i)7, change to read: ". . . reaches 1400°F and total a i r flow is at or

above purge rate." ~. In 5-2.1.2(j)3, change to read:

. . . reaches the 1400°F main temperature permit and total a i r flow is at or above purge rate." COMMITTEE STATEMENT: The changes made by the Committee are necessary to clear up this requirement as i t pertains to these other paragraphs.

(Log #28) 85H- 44 - (5-1.5(a)): Accept SUBMITTER: William Cunningham, Riley Stoker Corporation COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Revised text:

(a) Minimize the number of required equipment manipulations, thereby minimizing exposure to operting errors or equipment malfunction. SUBSTANTIATION: Changed the f i r s t word in the sentence and added THE. COMMITTEE ACTION: Accept.

(Log #29) 85H- 45 - (5~1.5.1(b)): Accept SUBMITTER: William Cunningham, Riley Stoker Corporation COMMENT ON PROPOSAL NO.: 85H-l RECOMMENDATION: Revised text:

" f lu id ized" not " f l u id i z ied . " SUBSTANTIATION: Spelling error. COMMITTEE ACTION: Accept.

(Log #21) 85H- 46 - (5-2.1.I(g) and (h)): Accept SUBMITTER: Courtney D. Alvey, Luthervi l le, MD COMMENT ON PROPOSAL NO.: 85H-l RECOMMENDATION: Delete "shall be" from each of these sections. S__UBSTANTIATION: Words redundant. The "shall" is in the f i r s t sentence. COMMITTEE ACTION: Accept.

(Log #36) 85H- 47 - ( 5 -2 . | . I ( I ) ) : Reject SUBMITTER: R. Shoemaker, American Electric Power COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Need to define "complete operational test . "

Need to define " l i s t test pass or fa i l c r i te r ia . " What are requirements i f fa i l to pass test.

SUBSTANTIATION: Need to c la r i fy that operational tests are more involved than pushing buttons and observing displays and alarms in control room. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The Committee believes that this requirement is suf f ic ient ly clear. The pass-fail c r i te r ia wi l l be established by the authority having jur isd ic t ion and the manufacturer.

(Log #22) 85H- 48 - ( 5 - 2 . 1 . 2 ( h ) ) : Accept SUBMITTER: Courtney D. Alvey, L u t h e r v i l l e , MD COMMENT ON PROPOSAL NO.: 85H-l RECOMMENDATION: Change "coa l " to " s o l i d f u e l . " SUBSTANTIATION: E d i t o r i a l - consistency. COMMITTEE ACTION: Accept.

3B

(Log #37) 85H- 49 - (5-2 .1 .2( i )5) : Accept SUBMITTER: R. Shoemaker, American Electr ic Power COMMENT ON PROPOSAL NO.: 85H-1 RECOMMENDATION: Add the fol lowing phrase:

"a f te r admission of fuel o i l " a f te r the phrase: " i f the burner ( i f used) f a i l s to l i gh t within lO

seconds." SUBSTANTIATION: The lO seconds to igni te rule is sometimes interpreted to be lO seconds a f te r i n i t i a t i o n by the operator, and i t takes several seconds to insert l ighters or otherwise stroke and ve r i f y status before oi l valve opens and admits fuel o i l to burner thereby leaving too l i t t l e time to establish and ver i f y an o i l flame (or gas). COMMITTEE ACTION: Accept.

(Log #46) 85H- 53 - (5 -2 .5 .1 . I (c ) ) : Accept S~JBMITTER: Nell Raskin/aose Martinez Lara, Pyropower Corporation COMMENT ON PROPOSAL NO.: 85H-I

I ECOMMENDATION: Revised text : "High bed temperture of furnace f lue gas ex i t

temperature." SUBSTANTIATION: On CFB's furnace ex i t gas temperature is more meaningful than bed temperature. I t is possible to operate with high bed temperature but with evaporative surface above same than the furnace exi t gas temperatue can be lower. COMMITTEE ACTION: Accept.

I COMMITTEE STATEMENT: Edi tor ia l Note: Change "of" to ,io r~1 .

(Log #5) 85H- 50 - (5-2 .1 .2( i )5) : Accept in Principle ~ : Dale E. Dressel, Monsanto Company COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Change the wording from:

". . . f a i l s to l i gh t within lO seconds.. ." to: ". . . f a i l s to l i gh t within 5 seconds a f te r fuel

admission to the furnace . . . . " Al ternately, i t could read:

" . . . f a i l s to l i gh t within lO seconds for gas and l i gh t o i ls or 15 seconds for No. 5 and 6 fuel o i l . " SUBSTANTIATION: This currently says lO seconds t r i a l for any fuel . NFPA 85A [section 6-2.4.2(c)] allows 15 seconds for No. 5 and No. 6 o i l . NFPA 85B and 85D allow f ive seconds fol lowing fuel admission to the furnace. COMMITTEE ACTION: Accept in Principle. COMMITTEE STATEMENT: See Comment 85H-49 (Log #37).

(Log #30) 85H- 51 - (5-2.2.5): Accept in Principle SUBMITTER: William Cunningham, Riley Stoker Corp. COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Revise as follows:

5-2.2.5 The stable operating philosophy of a f lu id ized bed shall be to maintain a bed temperature greater than 1400 deg. F and to i n i t i a t e a master fuel t r ip below this temperature. A lower solids fuel temperature wi l l be permitted (but not lower than 900 deg. F) provided the temperature has been ver i f ied through test and actual experience to safely igni te the main sol id fuel . SUBSTANTIATION: Try to maintain the same wording as found in paragraph 5- I .5 .1(h) . COMMITTEE ACTION: Accept in Principle.

Change "master" to "main" in f i r s t sentence. Make the second sentence an exception to this section. ~MMITTEE STATEMENT: The Committee believes these changes are more specif ic in describing these revisions.

(Log #38) 85H- 54 - (5 -2 .5 .1 .1 ( f ) ) : Accept in Principle ~ : R. Shoemaker, American Electr ic Power COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Change to "Air flow less than requirements of 5-2.2.6." SUBSTANTIATION: Not compatible with 5-1.3. COMMITTEE ACTION: Accept in Principle. COMMITTEE STATEMENT: See Committee Action on Comment 85H-43 (Log #2?).

(Log #31) 85H- 55 - (5-2.5.1.2(b) and (c) ) : Accept ~ : William Cunningham, Riley Stoker Corporation COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Revise as follows:

(b) Low drum level . (c) Loss of energy supply for combustion control or

inter lock systems. SUBSTANTIATION: The high drum level is not always required.

We should t r i p on loss of e i ther power supply. COMMITTEE ACTION: Accept.

(Log #64) 85H- 56 - (Chapter 6): Reject SUBMITTER: Martin M. Cot t re l l , Allentown, PA COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Waterside inter locks which are referenced 5-2.5.1.2 are not ident i f ied in section 6. We have no specif ic wording to propose other than raise the question. SUBSTANTIATION: Uncertain as to intent to include them. COMMITTEE ACTION: Reject. ~OMMITTEE STATEMENT: The wording in 5-2.5.1.2 is not intended to imply that these devices are intended to be interlocked on an automatic basis.

(Log #54) 85H- 52 - (5-2.5): Reject SUBMITTER: H. D. Ege, Jr . , Kansas City, MO COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: New text :

" I f a pressure part leak is suspected, fuel feed should be cut o f f and a i r flow continued unt i l bed temperatures drop below ign i t ion temperatures (900 F suggested) before t r ipping a i r . " SUBSTANTIATION: Emergency shutdowns: This does not address the condition where tube leaks in e i ther the main bed or in a external f lu id ized heat exchanger apply water or steam to the hot solid carbon, creating a condition simi lar to a gas i f ie r . Tripping a i r flow in this circumstance wi l l allow the system to generate hydrogen and CO. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: I t is very d i f f i c u l t to describe a suspect condition with an alarm. I t is also f e l t that this is too res t r i c t i ve from the operations standpoint.

(Log #6) 85H- 57 - (6-2 . I ) : Accept SUBMITTER: Dale E. Dressel, Monsanto Company COMMENT ON PROPOSAL NO~: 85H-1 RECOMMENDATION: Add the fol lowing parenthetical at end of paragraph:

"(See 5-2.5.1.I and 5-2.5.1.2) ." SUBSTANTIATION: Add parenthetical for c la r i t y and providing a helpful reference. COMMITTEE ACTION: Accept.

(Log #32) 85H- 58 - (6 -2 .3 ( i ) ) : Accept in Principle SUBMITTER: William Cunningham, Riley Stoker Corporation COMMENT ON PROPOSAL NO,: 85H-I RECOMMENDATION: Revise as follows:

"The mandatory master fuel t r i p and c i rcu i ts shall be independent of a l l other control system operation. Input sensors shall be dedicated to the t r i p system.

3/

I I f the signal is required for another control system, then i t may be furnished as an output signal from the inter lock system or shall be a redundant signal to that system." SUBSTANTIATION: IR bed temperature signals may be used to t r i p fuel but may also be required for temperature control in the combustion control logic. This would permit the same slgnal(s) to be used by the inter lock system, then retransmitted to the combustin control signal.

Please review the exception below ( i ) , i t appears that burner flame fa i l u re is an exception from the functional requirements. I do not believe this was the intent. COMMITTEE ACTION: Accept in Principle.

I Delete the last part of the th i rd sentence ". . . or shall be a redundant signal to that system." COMMITTEE STATEMENT: The Committee does not believe that the wording at the end of the third sentence is necessary.

Please review the exception below ( i ) , i t appears that burner flame fa i l u re is an exception from the functional requirements. I do not believe this was the intent. COMMITTEE ACTION: Accept in Principle. COMMITTEE STATEMENT: The Committee agrees with the commenter but also notes that Figure 4 currently covers the item of concern.

(Log #2) 85H- 62 - (Figure 3): Accept SUBHITTER: Robert P. Richmond, Baton Rouge, LA COMMENT ON PROPOSAL NO.: 85H-l RECOMMENDATION: In upper l e f t hand block of Figure 3, change " t r a i l " to " t r i a l . " SUBSTANTIATION: To correct typographical error. COMMITTEE ACTION: Accept.

(Log #39) 85H- 59 - (6-2.4): Reject SUBMITTER: R. Shoemaker, American Electr ic Power COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: I t is not practical or necessary to I "tune" actuation values and response times on inter lock I systems. Wording probably should be :

"Tile actuation values and response times of the i n i t i a t i n g devices shall be adequate to protect the furnace and equipment on which they are insta l led. Before i n i t i a l startup, each path and the complete system shall be tested to demonstrate the inter locks function as designed." SUBSTANTIATION: None. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The Committee believes that the current wording is su f f i c ien t . The commenter provided I no reasons for his proposed change and thus the I Committee is unclear as to the l ine of thinking which generated this comment.

(Log #50) 85H- 60 - (6-3.1.2): Accept in Principle SUBMITTER: Nell Raskin/Jose Martinez Lara, Pyropower Corp. COMMENT ON PROPOSAL NO.: 85H-l RECOMMENDATION: Revised text :

"The boi ler shall require a minimum of 25 percent a i r flow for not less than 5 minutes on 5 volumes changes." SUBSTANTIATION: Makes i t consistent with other parts of text . COMMITTEE ACTION: Accept in Principle.

Delete the last sentence of this paragraph. COMMITTEE STATEMENT: The de f in i t i on of unit purge wi l l sat is fy the intent of the submitter.

(Log #33) 85H- 61 - (6-3.1.4 and Figure I ) : Accept in Principle SUBMIITER: William Cunningham, Riley Stoker Corp. COMMENT ON PROPOSAL NO.: 85H-l RECOMMENDATION: None. SUBSTANTIATION: Figure l does not comply to the comments in paragraph 6-3.1.4.

The output from the master fuel t r ip device block should be NO mft to block 4, 7 and other sub-systems. I t is now shown as an input only when the mft is present.

The OR block (MFT RESET) should also have an input showing bed temperature greater than a given temperature.

(Log #23) 85H- 63 - (Figure 3): Accept SVBHITTER: Courtney D. Alvey, Lutherv i l le , MD COMMENT ON PROPOSAL NO.: 85H-l RECOMMENDATION: In "Loss of Warm-Up Burner" block, change " t r a i l " to " t r i a l . " SUBSTANTIATION: Edi tor ia l . COMMITTEE ACTION: Accept.

(Log #7) 85H- 64 - (Figure 4): Accept SUBHITTER: Dale E. Dressel, Monsanto Company COMMENT ON PROP_~)SAL NO.: 85H-l RECOMMENDATION: In Note I, change the word "Blocks" to "Items." SUBSTANTIATION: Blocks I-7 are labeled in Figure l. Blocks l , 2 and 3 are expanded in Figure 2, 3, and 4. Figure 4, Note l references blocks I-4 which could be confused with blocks I-4 in Figure I. Since al l the wri t ten material in 6-3.1.4 refers to the blocks in Figure 4 as items, i t seems logical to change the note to agree with the wri t ten material. COMMITTEE ACTION: Accept.

(Log #26) 85H- 65 - (Figure 4): Reject SUBMITTER: William Cunningham, Riley Stoker Corporation COMMENT ON PROPOSAL NO.: 85H-l RECOMMENDATION: None. SUBSTANTIATION: A note should be added to indicate that you need an absence of a l l t r ips to get permission to s tar t any systems. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The Committee believes that the diagram as shown is de f in i t i ve in showing the path of communication.

(Log #40) 85H- 66 - (7 -2 .1 ( i ) ) : Reject SUBMITTER: R. Shoemaker, American Electr ic Power COMMENT ON PROPOSAL NO.: 85H-I RECOMMENDATION: Change "below purge rate" to "within f ive percent of the requirements of 5-2.2.6." SUBSTANTIATION: Not compatible with 5-I .3. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: Purge rate is speci f ica l ly defined. The Committee does not know any reason why the value for purge rate should not be used for this requirement.

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PART IT

(Log #15) 851 - I - ( I - I . 2 ) : Accept in Principle SUBMITTER: H.D. Ege, Jr . , Burns & McDonnell Engineers COMMENT ON PROPOSAL NO.: 85I-I RECOMMENDATION: Page 13, Art. I-1.2. This refers to "refuse dried fue l " . The intent is probably "refuse derived fue l " . Since Art. 4-4 spec i f i ca l l y refers to municipal sol id waste, and discusses mass f i r i ng , "mass-fired municipal solid waste" should also be added in the f i r s t sentence. SUBSTANTIATION: The apparent intent of the Committee is to also include the mass f i red refuse incinerators. This is appropriate, in my opinion, since a mass f i red municipal sol id waste fed unit is a var iat ion of a stoker. However, doe pr imari ly to the extreme var iat ions in fuel qual i ty , size, and consistency, there are specif ic requirements for mass f i red incinerat ion units that must be incorporated into the standard i f i t is to be accepted as applicable. The principal consideration is that furnace "puffs" or pressure excursions are an expected, but abnormal, fact of everyday operation. There is no practical way of preventing them. They are caused by the explosive rupture and release, with consequent ign i t ion of vo la t i l e , flammable l iqu ids, which have been, usually, in closed containers, hidden inside a trash bag of other materials.

For example, a 400 ton per day mass f i red unit has an instantaneous fuel rate of about 37,000 BTU/sec. A quart of used paint thinner has a fuel content of about 38.000 BTU and wi l l probably burn in less than a second, since there is usually plenty of excess a i r in these units. I believe this would cause a sizeable p u f f .

An even worse, but s t i l l common si tuat ion occurs when that container breaks in handling in the input hopper, and a flashback f i r e occurs in the feed system. COMMITTEE A CTIO_N: Accept in Principle.

Replace "refuse dried fuel" with "municipal waste". COMMITTEE STATEMENT: The change proposed wi l l allow this to apply to any waste.

(Log #I) 851 - 2 - ( I -1 .2) : Accept in Principle SUBMITTER: Dale E. Dressel, Monsanto Co. COMMENT ON PROPOSAL NO.: 85I-I RECOMMENDATION: Change "refuse dried fuel" to "refuse derived fuel" SUBSTANTIATION: Spelling correction. COMMITTEE ACTI_ON: Accept in Principle. COMMITTEE STATEMENT: See Comment 851-I (Log #15).

4-4.1 Continuous simultaneous trend display of bo i ler output, feedwater flow rate, total fuel flow rate, total a i r flow rate as a percentage of maximum unit load, drum level , f ina l steam temperature, main steam pressure and furnace draf t shall be provided at the operating location (see 2-2.4, 2-4.2 and 2-4.4). SUBSTANTIATION: None. ~OMHITTEE ACTION: Accept in Principle.

Change paragraphs 2-2, 2-2.4 and 2-2.4(a) as shown: 2-2 Manufacture, Design and Engineering. 2-2.4 This guideline suggests a minimum degree of

automation. The trend toward more complex plants or increased automation requires added provisions for:

(a) Information about s ign i f icant operating events permitting the operator to make rapid evaluation of the operating s i tuat ion. The operator should have avai lable a continuous and useable display of c r i t i ca l trends which wi l l indicate conditions that may lead to unsafe operation. COMMITTEE STATEMENT: The changes made by the Committee on paragraphs 2-2, 2-2.4 and 2-2.4(a) wi l l add c la r i t y to these sections. Changes to paragraph 2-4.2 are rejected since exist ing paragraphs 2-4.2 and 2-4.3 are f e l t to be adequate. Changes to paragraph 4-4.1 are rejected since this material is redundant with paragraph 2-2.4(a).

(Log #17) 85I - 4 - (Chapter 3): Accept in Principle SUBMITTER: H.D. Ege, Jr . , Burns & McDonnell Engineers COMMENT ON PROPOSAL NO.: 85I-I RECOMMENDATION: Chapter 3 Def in i t ions. Defini t ions are suggested for the fol lowing:

Agglomerating, Non-agglomerating. Rotary k i ln type grate, rotary grate, v ibratory grate, pinhole grate, mass f i r i ng . SUBSTANTIATION: The intent of the document is to cover a l l types of stoker f i r i ng , and there are several specialized stokers that might claim that the standard does not apply.

In par t icu lar , the rotary k i ln , as used for mass f i r i n g of municipal waste should be included, since i t gaining acceptance in a growing industry. COMMITTEE ACTION: Accept in Principle.

Add the following de f in i t ion : Agglomerating. A character ist ic of a coal which

causes coking on the fuel bed during vo l i t a l i za t i on . COMMITTEE STATEMENT: Non-agglomerating is the negative of agglomerating and therefore not needed. Vibratory Grate is covered by the de f in i t ion for Vibrating Grate. Mass Fir ing is covered in section 4-4.1. The other requested def in i t ions are not in the document and therefore are not needed.

(Log #16) 851 - 3 - (2-2 and 4-4.1): Accept in Principle SUBMITTER: H.D. Ege, Jr . , Burns & McDonnell Engineers COMMENT ON PROPOSAL NO.: 851-I RECOMMENDATION: Revise text as follows:

2-2 Manufacturing, Design and Engineering. 2-2.4 This standard requires a minimum degree of

automation (6- I .2 ) . The trend toward more complex plants or increased automation requires added provisions for :

(a) Information about s ign i f i cant operating events permitting tile operator to make rapid evaluation of the operating s i tuat ion. The operator shall be provided with continuous and usable displays of c r i t i ca l trends which wi l l indicate conditions that may lead to unsafe operation.

2-4.2 Furnace explosions have occured as a result of unfavorable functional design. Frequently, the invest igat ion has revealed human error, and has completely overlooked the chain of causes which triggered the operating error . Therefore, the design. ins ta l la t ion and functional objectives of the overall system of components and the i r controls shall be integrated. Consideration shall be given to the human-machine relat ionships which wi l l ex ist dLlring tile operating l i f e of the system.

(Log #2) 85I - 5 - (Chapter 3): Reject SUBMITTER: Dale E. Dressel, Monsanto Co. COMMENT ON PROPOSAL NO.: 85I-1 RECOMMENDATION: In the def in i t ions for ( I ) Chain Grate Stoker, (2) Overfeed Stoker (b) Chain or Traveling Grate, and (3) Spreader Stoker (c), Continuous Ash Discharge or Traveling Grate, change the words "moving endless" to "revolving". SUBSTANTIATION: I feel that the word "revolving" better conveys the intent than "moving endless". COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: This term has been the convention for some IO0 years in this industry.

(Log #3) 851 - 6 - (4-3.1): Accept in Principle SUBMITTER: Dale E. Dressel, Monsanto Co. COMMENT ON PROPOSAL NO.: 851-I RECOMMENDATION: I t is suggested that a def in i t ion of "Hogged Fuel" be included. I t is used in paragraph 2, third l ine from bottom. Using ABMA def in i t ions, hogged fuel could be defined as "wood refuse af ter being run through a machine which forms chips or shreds of approximately uniform size."

39

SUBSTANTIATION: While a common term in the industry, "hogged fuel" wi l l not be a fami l ia r term to everyone. COMMITTEE ACTION: Accept in Principle.

Add de f in i t i on as follows: Hogged Fuel. Wood refuse a f te r being chipped or

shredded by a machine known as a hog. COMMITTEE STATEMENT: The de f in i t i on proposed by the Committee is from the ABMA Lexicon.

(Log #18) 851 - 7 - (4-6.2.3): Reject S VBMITTER: H.D. Ege, Jr . , Burns & McDonnell Engineers COMMENT ON PROPOSAL NO.: 85I-I RECOMMENDATION: Page 18 add:

4-6.2.3 Mass f i red municipal sol id waste is municipal refuse, burned just as i t is collected. As such, i t is unpredictable in content, causing severe var iat ions in fuel input to the stoker, not only in terms of BTU content, but also in burning time and in mixing capabi l i t ies . This forces excess a i r to very high levels to assure complete combustion, and also causes var iat ions in f i r i n g rate. I t contains occasional containers of highly vo la t i l e flammable l iquids which cause puffs and flashbacks through the feed system. SUBSTANTIATION: None. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The Committee believes that the current wording in paragraph 4-4.1 is adequate and that this proposed paragraph adds nothing new.

(Log #5) 85I - 8 - (5-2.10): Accept S_VBMITTER: Dale E. Dressel, Monsanto Co. COMMENT~N~AL NO.: 85I-I RECO_MMENDAT~N: In last l ine of last paragraph, delete the parenthetical, "(See Figure 3)." SUBSTANTIATION: Parenthetical reference is extraneous. COMMITTEE ACTION: Accept.

(Log #19) 851 - 9 - (5-2.12): Reject ~BMITTER: H.D. Ege, Jr . , Burns & McDonnell Engineers COMMENT ON PROPOSAL NO.: 85I-I RECOMMENDATI(~N: Page 20 add a second paragraph under 5-2.12:

"Other types o f g ra te systems f o r mass f i r e d municipal s o l i d waste such as the r o ta r y water cooled k i l n ( the O'Connor combustor), uncooled r o ta r y k i l n s , and p a r t i a l ox i da t i on s t a t i o n a r y grates are a lso to be considered as s toker systems under t h i s s tandard . " SUBSTANTIATION: None. COMMITTEE ACTION: Reject . COMMITTEE STATEMENT: The Committee be l ieves tha t t h i s is beyond the scope of t h i s standard. They do not c l a s s i f y a k i l n as a type of s toker .

(Log #6) 851 - lO - (5-2.12): Accept SUBMITTER: Dale E. Dressel, Monsanto Co. COMMENT ON PROPOSAL NO.: 851-I RECOMMENDATION: A reference to Figure 4 is made in the f i r s t l ine but the f igure has no s im i la r i t y to the paragraph describing an MSW stoker which talks about a staircase type grate. My comment is that e i ther the parenthetical expression, "(See Figure 4)" should be deleted or a f igure should be obtained that agrees with the wording in 5-2.12. SUBSTANTIATION: Figure referenced does not complement the wri t ten words in the section. COMMITTEE ACTION: Accept. COMMITTEE STATEMENT: Ed i tor ia l , delete reference.

(Log #12) 85I - I I - (5-4): Reject SUBMITTER: William Cunningham, Riley Stoker Corp. COMMENT ON PROPOSAL NO.: 85I-I RECOMMENDATION: Revise text as follows:

5-4 Auxi l iary gas and/or o i l burners may be located above the stoker, these burners shall conform with NFPA 85A. When more than one package burner is furnished, i t shall conform with NFPA 85B and/or 85D.

The piping systems may conform to 85A, when two or more package burners are mounted above the stoker. SUBSTANTIATION: Today, i f a stoker f i red boi ler has one package burner, NFPA 85A is followed. However, i f two burners are furnished i t has been the practice of some burner suppliers to fol low 85A in regard to the piping arrangement and the multiple burner standard in regard to common t r ips and purge.

The stoker standard should provide some guidance as to the correct path to fol low in regard to package burners, which are common on today's boi lers. The purpose the burner manufactures using 85A, is to permit a complete system which is wired and piped as an assembly, to be furnished with the burner. Please note that 85A does require two oi l shut-off valves. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The Committee notes that current wording in paragraphs l - l . 4 and I-2 already cover the concern raised by the commenter.

(Log #7) 851 - 12 - (5-4.2.1): Accept in Principle SUBMITTER: Dale E. Dressel, Monsanto Co. COMMENT ON PROPOSAL NO.: 851-I RECOMMENDATION: Include "ash removal" in the subsystems referenced and insert a new section 5-4.2.3(e) for the ash removal subsystem as shown below. Wording is largely taken from Section 4-1.2.2(h) of 85H on f lu id ized bed boi lers.

(e) Ash Removal Subsystem. I. The grate subsystem and f lue gas cleaning

subsystem shall be sized and arranged to remove the ash at least at the same rate i t is generated by the fuel burning process during unit operation.

2. Convenient access and drain openings shall be provided.

3. The removal equipment handling hot ash from the boi ler shall be designed to provide ef fect ive material cooling before discharging material into conventional ash handling and storage equipment. Safety interlocks with a device to monitor cooling water f low/or material discharge temperature shall be required to prevent f i res or equipment damage. SUBSTANTIATION: Ash removal is as much a fuel burning subsystem as combustion products removal and should be included. COMMITTEE ACTION: Accept in Principle.

Add "ash removal" a f te r "combustion products removal" in paragraph 5-4.2.1.

Add a new section (e) to paragraph 5-4.2.3 as follows: (e) Ash Removal Subsystem. I. The grate subsystem and f lue gas cleaning

subsystem should be sized and arranged to remove the ash at least at the same rate i t is generated by the fuel burning process during unit operation.

2. Convenient access and drain openings should be provided. COMMITTEE STATEMENT: The proposed item 3 is rejected since i t is applicable to f Iu id ized bed and not stoker.

(Log #21) 851 - 13 - (5-4.2.2(c)2): Accept in Principle SUBMITTER: H.D. Ege, Jr . , Burns & McDonnell Engineers COMMENT ON PROPOSAL NO.: 85I-I RECOMMENDATION: Page 21 add:

5-4.2.2(c)2 Observation ports and lancing doors for mass f i red MSW units shall be provided with vision ports which wi l l permit observation and operation of the unit while puffs are expected and occurring. Glasses shall be replaceable without taking the unit out of service. Lancing ports shall be equipped with aspirators or other devices to safely permit lancing of the fuel bed without res t r i c t ing operations.

40

SUBSTANTIATION: None. COMMITTEE ACTION: Accept in Principle.

Ed i to r ia l l y rearrange this section by changing the exist ing 5-4.2.3(c)(3) to 5-4.2.3(c)(4) and insert ing the new text as follows:

5-4.2.3(c)(3) Observation ports and lancing doors for mass f i red MSW units should be provided with vision ports which wi l l permit observation and operation of the unit while puffs are expected and occurring. Glasses should be replaceable without taking the unit out of service. Lancing ports should be equipped with aspirators or other devices to safely permit lancino of the fuel bed without res t r i c t ing operations. COMMITTEE ~TATEMENT: The changes made by the Committee wi l l add c la r i t y to this section.

(Log #22) 85I - 14 - (5-4.2.2(c)4): Reject SUBMITTER: H.D. Ege, Jr . , Burns & McDonnell Engineers COMMENT ON PROPOSAL NO.: 85I-I RECOMMENDATION: Page 21 add:

5-4.2.2(c)4 Note: The ASME Boi ler Code (PG61.1 and PG61.2) requires that units with a large mass of store~ energy in the f i r i n g system be equipped with steam driven boi ler feed pumps so boi ler water level can be maintained in the event of power fa i l u re . This applies to most stoker f i red boi ler systems other than the spreader stoker. (This note may better f i t into 6-5.4.) S UB_STANTIATION: None. C OMMITTE~ION: Reject. COMMITTEE STATEMENT: This material is covered by ASME Boi ler Code, and is beyond the scope of NFPA 85I.

(Log #20) 85I - 15 - (5-4.2.3(b)3): Accept in Principle S ~ : H.D. Ege, Jr . , Burns & McDonnell Engineers COMMENT ON PROPOSAL NO.: 851-I RECOMMENDATION: Page 21 add:

5-4.2.3(b)3 Mass f i red municipal sol id waste f i red systems shall incorporate detection and f i r e extinguishing devices into and over the feed system to extinguish and control the flashbacks of fuel as i t is being fed into the furnace. Extinguishing devices shall be capable of being used repeatedly without taking the unit out of service. SUBSTANTIATION: None. COMMITTEE ACTION: Accept in Principle.

Change the "shal ls" to "should". Change "devices" to "systems" in two places.

COMMITTEE STATEMENT: The document is a recommended practice and therefore, the word should is appropriate. Fire extinguishing systems is a more defined term.

(Log #8) 851 - 16 - (5-4.2 .3(c) I ) : Accept in Principle SUBMITTER: Dale E. Dressel, Monsanto Co. COMMENT ON PROPOSAL NO.: 85I-I RECOMMENDATION: Change "stable furnace pressure" to "stable combustion." SUBSTANTIATION: Furnace design helps maintain stable combustion, not furnace pressure. Furnace pressure is controlled by combustion products removal subsystem. COMMITTEE ACTION: Accept in Principle.

Change to read: ". . . maintain stable combustion and minimize

furnace pressure f luc tuat ion . " COMMITTEE STATEMENT: The Committee believes the revised changes wi l l sa t is fy the intent of the submitter.

Replace the above and the caution note with: "Place kindl ing on fuel bed and fol low manufacturer's

operating guide l ines to igni te the k indl ing." SUBSTANTIATION: Riley does not recommend this.

Par. 6-4.1NFPA t e l l s the operator to fol low step 6 - ] . l ( c ) i f a cold s tar t or i f no grate f i r e is seen. Operators, have been injured when, not believing there was an active f i r e , they sprayed oi l onto the grate, causing a f lash back, which burned the operator. COMMITTEE ACTION: Accept in Principle.

Revise Section 6-1.1 as follows: 6 - I . I Start Up Procedures (Cold Start) . (a) Prior to star t ing ID fans ver i f y an open flow

path from the in le t of the FD fan to the stack. Unless there is su f f i c ien t natural dra f t for i n t i t i a l f i r i ng , the induced draf t fan should be started and normal furnace draf t maintained.

(b) Veri fy that grate is clear of ash and debris. (c) F i l l feeder hopper with fuel , s tar t feed

mechanism and establish a bed of fuel on the grate. (d) Place kindling on fuel bed. Spray the kindling

from outside the furance with a l i gh t coat of d i s t i l l a t e o i l .

CAUTION: Gasoline, alcohol or other highly vo la t i l e material must not be used for l i g h t - o f f .

(e) Open furnace access door, l i gh t a torch and igni te wood by passing torch through the door.

( f ) When wood on bed of fuel is burning, star t ID fan, i f not in operation, and place in automatic mode of operation.

(g) The over f i re a i r fan should be started immediately to prevent damage from gases passing through the ductwork.

CAUTION: Undergrate a i r pressure should always be greater than furnace pressure to prevent reverse flow and potential unit damage.

(h) When fuel bed is act ively burning, s tar t FD fan with dampers at minimum posit ion.

( i ) Start fuel feed. Observe operation and adjust fuel rate and a i r as required unt i l bo i ler steam pressure is at normal operating pressure.

( j ) Place fuel and a i r in automatic mode of operation.

Revise Section 6-4.1 as follows: 6-4.1 When i t is desired to restar t the unit a f te r

i t has been bott led up under pressure for a short time, and grate burning has stopped, fol low cold star t procedure - Section 6- l (d) through (g) and 6-1.1(a) through ( j ) . I f grate f i r e is continuing, fol low the Cold Start Procedure - Section 6-1.1(a) through ( j ) ommitting (b), (d) and (e). COMMITTEE STATEMENT: Don't want to spray o i l into a hot grate because of the poss ib i l i t y of flashback. Some of the steps can be omitted during a manual hot restar t in order to reduce the poss ib i l i t y of flashback.

(Log #14) 85I - 18 - (6 -1 .1 ( f ) ) : Reject SUBMITTER: William Cunningham, Riley Stoker Corp. COMMENT ON PROPOSAL NO.: 851-I RECOMMENDATION: Revise text as follows:

"CAUTION: Undergrate a i r pressure should always be greater than furnace pressure to prevent reverse flow and potential unit damage. This is true at high boi ler loads." SUBSTANTIATION: Please note that the Forced Draft Fan is started in g and therefore this can not happen at this point in time. At low boi ler loads, there is l i t t l e or no measureable undergrate a i r pressure. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The Committee believes that since this is a guide as opposed to standard, that the current wording is su f f i c ien t .

(Log #13) 851 - 17 - (6 - I . I ( c ) and 6-4.1): Accept in Principle SUBMITTER: William Cunningham, Riley Stoker Corp. COMMENT ON PROPOSAL NO.: 851-1 RECOMMENDATION: Revise text as follows:

"Place kindl ing on fuel bed. Spray the kindl ing from outside the furnace with a l i gh t coat of d i s t i l l a t e o i l . "

(Log #23) 851 - 19 - (6-1.5): Reject SUBMITTER: H.D. Ege, Jr . , Burns & McDonnell Engineers COMMENT ON PROPOSAL NO.: 851-I RECOMMENDATION: Page 22 add:

6-I .5 Emissions control requirements for burning of many waste materials require maintenance of hydrocarbon destruction temperatures in the furnace (1600F for 2 seconds or greater), which may require operation and

41

warmup of such units on aux i l ia ry fuels before any waste materials can be fed into the furnace. SUBSTANTIATION: None. ~MMITTEE ACTION: Reject. COMMITTEE STATEMENT: This item is beyond the scope of the Committee to specify such recommendations. The Committee believes that enough guidance is provided in this document to account for the commenter's concern.

(Log #24) 851 - 20 - (6-5.2): Reject S]JBMITTER: H.D. Ege, Jr . , Burns & McDonnell Engineers COMMENT ON PROPOSAL NO.: 851-I RECOMMENDATION: Page 23 add to 6-5.2:

6-5.2 Devices such as baghouses or high resistance scrubbers shall be automatically bypassed in the event of ID fan t r ip . Bypasses shall be large enough to permit the system to natura l ly draf t the furnace to _ _ percent of normal f u l l load f lue gas flow. SUBSTANTIATION: None. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: