replacing a stack gas flow hardware device with pems
TRANSCRIPT
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PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Presented by:
Brian Swanson, President
CMC Solutions, L.L.C.
Replacing a Stack Gas Flow Hardware Device with PEMS
1
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Introduction CMC Solutions was retained to perform a
demonstration of a statistical hybrid predictive emissions monitoring system (PEMS) under 40 CFR Part 75, Subpart E.
The PEMS was deployed in September of 2010 for stack gas flow and pollutant emissions.
The demonstration confirmed that the PEMS passes all the statistical tests for the 720 hour demonstration period.
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
PEMS Technology Early models included first principle theoretical
models by OEMs.
Commercial PEMS available on the market include first principles and empirical models.
Empirical models such as neural network and statistical hybrid have passed EPA requirements.
Hundreds of PEMS are used in the U.S. today for compliance monitoring under EPA rules.
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Performance Testing Methods 40 CFR Part 75, Subpart E demonstration – 720 hours
of PEMS vs. CEMS data, 24 hours each additional fuel
PS-16 Relative Accuracy Test Audit (RATA)
27 runs (9 at each of three loads)
Relative Accuracy FLOW PEMS was 2 percent
F Test
Correlation
Data Availability
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
PS-16 RATA Testing 27 Run RATA Testing
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
PEMS QA Sensor validation – model envelope excursions for
empirical models
Sensor quality assurance and PEMS QA programming
Periodic Audits (RAA)
Annual recertification (RATA) tests
Model updates and tuning of empirical models
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
PEMS QA Programming QA Plan developed around input parameters
INPUT DESCRIPTION UNITS MIN MAX
Input24*
Unit Load Set Point
MW
2.34
99.92
Input56* Total Gas kscfh 0.60 1003.96
Input4 Boiler Feed-water flow kpph 0.00 748.10
Input22 Unit Megawatts MW 0.00 101.92
Input23 Unit Megawatt Demand MW 0.00 100.09
Input34 1st Stage Pressure psi 0.00 1371.40
Input37 Hot Reheat Steam Pressure psi 0.00 442.30
Input45 Top Wind-box Pressure inwc 1.20 37.60
Input46 MID Wind-box Pressure inwc 1.30 27.12
Input47 BTM Wind-box Pressure inwc 0.10 29.60
Input60 Auxiliary Steam Pressure DMD % 0.00 100.00
Input74 Steam Flow kpph 1.30 684.70
TABLE II - MODEL ENVELOPE
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Results The raw minute data output from the CEMS data
acquisition system was quality assured. The PEMS was deployed in the September of 2010 for stack gas flow and pollutant emissions.
An X-Y plot of the PEMS values against the CEMS values is presented. Also included in the report is a graph of the percentage differences between the CEMS and PEMS for each hour record.
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Performance Evaluation Statistical Hybrid PEMS met requirements.
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Performance Evaluation Stack Gas Flow PEMS vs. CEMS XY Plot
0
50
100
150
200
250
300
350
400
450
500
0 50 100 150 200 250 300 350 400 450 500
Stac
k Fl
ow
-CEM
S kM
3/h
r
Stack Flow-PEMS kM3/hr
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Performance Evaluation Stack Flow Rate PEMS vs. CEMS X-Y PLOT.
-250
-200
-150
-100
-50
0
50
100
150
200
250
1 51 101 151 201 251 301 351 401 451 501 551 601 651 701
Pe
rce
nta
ge
Dif
fere
nc
e C
EM
S v
s P
EM
S
Hours
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Performance Evaluation Statistical Hybrid PEMS met requirements.
Test Value EPA Limit High/Low Limit Pass/Fail
F Test
0.845
<
0.88 High Limit Pass
Correlation
0.899
>
0.8 Low Limit Pass
Data Availability
0.97
>
0.9 Low Limit Pass
TABLE I – 720 HOUR STATISTICAL ANALYSIS
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Conclusion CMC Solutions PEMS was capable of meeting the most
stringent requirements for monitoring stack gas flow on gas and oil fired boilers.
The PEMS was reliable and accurate.
The demonstration confirmed that the PEMS was accurate under both base-load and startup conditions along with transitional load periods.
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Introduction
14
Federal regulations require continuous monitoring of NOx , CO, SO2, O2 and/or CO2 from industrial processes in the United States
A statistical hybrid PEMS has been employed at a number of compliance sites in the United States
Brief History of CEMS/PEMS development PEMS have been used for compliance since the 70’s
Advantages of PEMS PEMS are less Costly PEMS are easier to maintain
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
CEMS Components / Maintenance
Sample Probe
Umbilical
Analyzers
Gases
Pumps
Filters
Controllers
Computer
Air Source
Spare Parts
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Why consider PEMS?
SmartCEM® is a proven and patented product Guaranteed to meet U.S. EPA regulations Supported by a network of professionals Virtually no maintenance or operational costs PEMS model can be updated by owner
In addition, SmartCEM® can be setup quickly
The model is developed and retrained onsite Replaces your existing CEMS No spare parts, analyzer repairs, emergency service
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
PEMS History and Use in Compliance Monitoring for 40 CFR Regulations
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PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
PEMS Design and History
PEMS are not new, they evolved … Introduced in the 1970s
Parametric and First Principles initially
First PEMS were NSPS (40 CFR Part 60)
OEM models, GE, Solar, others (~ 500 worldwide)
Empirical Methods introduced in the 1980s
PEMS on the market today are theoretical First Principles (Parametric) and Empirical (Neural Network, and Statistical Hybrid Methods)
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Regulatory Selection Criteria Monitoring Primary Pollutants (NOx, SOx, CO)
PEMS may be used as an alternative to CEMS for all gas or oil-fired boilers and turbines
Parametric, PEMS, or CEMS approaches can be used for all smaller units (< 100 mmBTU)
CEMS must be used on some units that fire solid fuels such as municipal waste (> 250 mmBTU)
Local agencies may require monitoring of specific pollutants in non-attainment (SO2, NH3, CO or VOC PEMS optional measurements)
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
PEMS Regulatory Selection Matrix 40 CFR Part 75 Yes, as 40 CFR Part 75, Subpart E
P1, P2, and Subpart H alternate Electrical Generating Units
40 CFR Part 60 Yes 40 CFR Part 60, Appendix B, PS-16
Subpart Da, Db, Dc Boilers (All Fuels)
40 CFR Part 60 Yes 40 CFR Part 60, Appendix B, PS-16
Subpart GG or KKKK Turbines (Gas and Oil Fired)
Clean Air Interstate Rules Yes, as 40 CFR Part 75, Subpart E
CAIR alternate All Affected Units (All Types)
Maximum Achievable Technology Yes, as 40 CFR Part 60, Appendix B, PS-16
MACT alternate Boilers (All Fuels)
Continuous Assurance Monitoring Yes All Affected Units (All Fuels)
CAM
Voluntary Superior Monitoring Yes All Affected Units (All Fuels)
VSM
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
PEMS Classifications
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Parametric Systems
Predictive Systems
Theoretical “First principle” method
Empirical Neural network
Statistical hybrid
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Parametric Systems
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PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Features of Parametric Systems
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Simple formulaic approach
Accuracy is very limited
No flexibility – if signal is lost, no prediction is available
Do NOT predict excess emissions
Are NOT certified as an alternative to CEMS
Acceptable for peaking units with less than 10% operating time in a given year
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Theoretical Predictive Systems
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PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Features of Theoretical PEMS
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Complex formulaic approach
Accuracy is maintained when unit is operated as it was in the factory or under similar ambient conditions
No flexibility – if critical signals are lost, prediction is lost
Can only be verified against limited factory test data
Can be certified as an alternative to CEMS
Many implementations have been removed due to failure to meet ongoing quality assurance tests or respond to unit changes that are not reflected in the formula
Expensive to maintain and requires specialized staff
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Empirical Neural Network Predictive Systems
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PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Features of Neural Network PEMS
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Complex neural network approach
Requires extensive up front testing with specialized staff onsite in an iterative process
Accuracy is maintained when unit is operated as it was in the initial setup or under similar ambient conditions
Can be certified as an alternative to CEMS
Some implementations have been removed due to expense and support required to pass QA audits
Expensive to maintain and requires specialized staff
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Empirical Statistical Hybrid Model
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PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Features of the Statistical Hybrid
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Robust Model that is accurate across the full load of the unit including all normal operating conditions and during transitional states such as startup and shutdown
Equivalent accuracy as a CEMS with superior reliability
Flexibility to be implemented using existing instrumentation
Can certify as an alternative to CEMS
Systems in operation around the world today on gas turbines both in the U.S. and in the E.U.
Virtually no maintenance – no specialized staff required and can be maintained by operators or other staff onsite
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Statistical Hybrid Advantages
30
Requires no specialized staff to maintain
Model can be developed without a great deal of knowledge of the underlying process or chemistry
Highly reliable with options for data recovery
Minimize or eliminate monitor downtime
Can generate predictions with a variety of inputs
Can generate predictions with inputs that fail
Can be retrained by non-specialized staff
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Features of the Statistical Hybrid
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Can be assessed using quality control procedures defined to meet the requirements of U.S. EPA
Can be developed and retrained by non-technical onsite staff or consultants using third party test data during normal operations
Can be tested against EPA reference methods and has been demonstrated at multiple sites on various gas turbine classes to meet 40 CFR Part 75, Subpart E
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Example Applications
32
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Applications
33
Gas and liquid fuel fired turbines
Gas and liquid fired boilers
Gas fired ethanol plant boilers
Petroleum refinery processes
Other continuous systems
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Gas and Liquid Fired Turbines
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Applied to turbines from 60kW to 180 MW
Fuels included natural gas, deisel, and fuel oil
Equipped with a variety of control technologies including dry low NOx, steam and water injection, SoloNox, and post combustion SCR
Turbines were from a variety of manufacturers
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
NOx PEMS Time Plot
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PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
NOx PEMS XY Plot
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PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Gas and Liquid Fired Boilers
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Applied to boilers from 100 mmBTU to 750 mmBTU
Fuels included natural gas, blast furnace gas, coke oven gas, refinery gas, and fuel oil
Equipped with a variety of control technologies
Boilers were from a variety of manufacturers
PEMS developed with existing instrumentation and input parameters readily available from distributed control system
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Oil Fired Boiler O2/NOx Time Plot
38
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Oil Fired Boiler CO/CO2 Time Plot
39
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
RATA Test Results
Relative Accuracy Test Audit (RATA) was conducted to certify the results
40
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
RATA Test Procedures
41
Uses U.S. EPA reference methods (RM)
The RM was compared to the PEMS predicted emissions
The process was tested under three operating loads
3 or 4 test runs conducted at each load with a duration of 21 minutes each
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
RATA Conducted on 3 Processes
42
Ethanol plant boiler rated at 100 mmBTU/hr located in Western Iowa
170 MW combined cycle turbine at a power plant in Detroit, Michigan
750 mmBTU/hr boiler firing pipeline natural gas and blast furnace gas
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
RATA at Ethanol Plant
43
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
1 2 3 4 5 6 7 8 9 10 11 12
Test Run
NO
x lb
/mm
btu
RM
PEMS
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
RATA on Power Plant Turbine
44
0.027
0.028
0.029
0.030
0.031
0.032
0.033
0.034
1 2 3 4 5 6 7 8 9
Test Run
NO
x lb
s/m
mb
tu
RM
PEMS
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
RATA at Power Plant Boiler
45
0.000
0.020
0.040
0.060
0.080
0.100
0.120
0.140
0.160
1 2 3 4 5 6 7 8 9
Test Run
SO
2 l
b/m
mb
tu
RM
PEMS
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
PEMS Quality Assurance
46
Instrumentation was subjected to annual QA
QA follows 40 CFR Part 75, Appendix B
QA manual is prepared and placed next to PEMS server for documenting all QC activity
System maintenance, database maintenance, and data backup procedures are instituted
All PEMS QC procedures and audits are documented in QA manual
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Summary
47
Statistical hybrid PEMS have been successful in meeting the requirements of the U.S. emission trading program
PEMS achieve very high accuracy levels
PEMS demonstrate superior reliability
PEMS are certified as an alternative to CEMS
PEMS are a cost-effective alternative to a CEMS
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
PEMS vs. CEMS XY Plot
48
PNWIS & AWMA 52nd Annual Conference | Portland, Oregon The Nines Hotel | November 7 through 9, 2012
Concluding Remarks
49
Advanced empirical PEMS have been used successfully in the U. S. for 40 CFR Compliance
PEMS achieve very high accuracy levels
PEMS demonstrate superior reliability
PEMS can be certified as an alternative to CEMS
Some PEMS require no specialized support making them ideal for offshore and remote applications
A robust statistical hybrid model is a cost-effective solution for continuous monitoring applications