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Minutes of Meeting of the Sub Committee on Normalization (Cement Sector)

Date:20 March 2013

Time:11.00 AM to 1.30 PM

Location:Conference Hall, Sewa Bhawan, New Delhi

Participants: As per Annexure - I

1. The Agenda for the meeting was to discuss and conclude the normalization factors

developed so far as per minutes of Minutes of 3 rdTechnical committee meeting held on 23-

24thNovember 2012 at ACC Thane office.

2. The note of deliberations and recommendations discussed during the meeting are as under

i) Normalization of Clinker Heat rate and clinkering electrical energy versus

clinker capacity utilization of the kiln.

The committee agreed for a normalization factor developed by NCCBM. The study

indicates there is 6 % increase in heat rate when the capacity utilization falls to 55%

of the rated value. Brief summary of the study is given below.

Theoretical analysis for 6-stage ILC 4500 tpd kiln operated at different reduced output rates:

Kiln Output TPD 4500 4000 3500 3000 2500

Heat

output PH Waste gas 132.08 132.78 133.7 134.92 136.61Dust 3.79 3.78 3.79 3.83 3.83

Heat of Reaction 411.46 411.46 411.46 411.46 411.46

Cooler exhaust 82.71 82.12 81.38 80.42 79

Clinker 26.91 26.91 26.91 26.91 26.91

Evap. Of moisture-RM 1.23 1.23 1.23 1.23 1.23

Evap. Of moisture-fuel 1.1 1.11 1.12 1.14 1.16

Radiation losses 40 50 55 65 80

TOTAL 699.28 709.39 714.59 724.91 740.2

Heat Input Sensible heat 30 30 30 30 30

Through fuelcombustion 669.28 679.39 684.59 694.91 710.2

TOTAL 699.28 709.39 714.59 724.91 740.2

Note:Values in kcal/kg cl.Heat balance computed through software, past energy audit studies & input from NCB cementsimulatorValues of radiation losses arrived at based on NCB past energy audit studiesFurther exercise on simulator is being carried out and also for different kiln capacities


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Fig 1: Kiln TPD vs Thermal SEC

Based on the above:

% Output % Increase in kcal/kg cl.

100 -

88 1.4

77 2.3

66 3.8

55 6

For specific electrical energy upto clinkering vs. Percentage Capacity utilization,

NCCBM has agreed to conduct simulator based study and are expected to share

the result by 5thApril 2013.

To avail this Normalization, DC should submit data related to kiln under utilization

due to market demand, coal non availability due to force majure conditions like

floods, strikes etc.

During the assessment period, the DCs will provide the number of hot-cold-hot star

ups so that this feature can be included for normalization in the subsequent cycles.

ii) The normalization factor for Coal GCV vs. CPP Heat rate

y = -0.0195x + 755.83

R = 0.971

y = 4E-06x2- 0.0504x + 807.79R = 0.9885

665

670

675

680

685

690

695

700

705

710

715

2000 2500 3000 3500 4000 4500 5000 5500

kcal/kg

cl.

TPD

Kiln TPD Vs kcal/kg cl.

Series1 Linear (Series1)Poly. (Series1)


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BEE has proposed the following equation for the relationship between GCV of coal

vs. boiler efficiency:

Boiler efficiency = 92.5-[{50*A+630(M+9H)}/GCV]

A= Ash percentage in Coal

M= Moisture percentage in CoalH= Hydrogen percentage in Coal

GCV = Gross Calorific value in Kcal / Kg

But, for applying above the formula, the data related to Hydrogen content in the coal

should be available during the baseline and assessment year. It was agreed to use

the value of Hydrogen percentage of the assessment year in the baseline year

also if the data is not available.

iii) Normalization factor for PETCOKE usage in cement kilns:

The suggested relationship between the percentage (0-100%) use of petcoke and

the heat rate of the kiln & Sp. Power (upto Clinkerisation) by M/s Ultratech was

discussed (shown in fig 2 and fig3).

NCCBM has agreed in general about the variation of specific thermal and electrical

power with respect to pet coke substitution.

The committee decided to populate the data and finalize the percentage of increase

in thermal and electrical energy consumption by the petcoke usage over and above

baseline. ACC agreed to share the data by 5th April 2013 and provided below (fig

2and fig3). In both cases, similar percentage increase in thermal and electrical

SEC was observed.


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Fig 2: Variation of specific heat with percentage of petcoke consumption at KCW and

ACC Chaibasa

Fig 3: Variation of specific power with percentage of petcoke consumption at KCW

and ACC Chaibas

y = 0.1293x + 688.2

R = 0.9985

y = 0.2615x + 790.13

R = 0.9249

650

700

750

800

850

0 20 40 60 80 100 120

ThermalSEC,

kCa

l/kg

% Petcoke

Thermal SEC vs % Petcoke usage

KCW Ultratech ACC Chaibasa

y = 0.2065x + 68.95

R = 0.9556

y = 0.0215x + 54.883

R = 1

0

20

40

60

80

100

0 10 20 30 40 50 60 70 80 90 1Ele

ctricalSECuptoclinkering,

kWh/To

fclinker

% Petcoke

Electrical SEC upto Clinkering vs% Petcoke usage

ACC Chaibasa KCW, Ultratech


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iv) Specific Heat Rate to be considered for export of Power from Cement Plant

CPP:

For export of energy, it is being proposed that the difference of units exported above

the base line would be corrected based on the actual CPP heat rate of assessment

year while calculating the total energy.

The committee agreed and this issue is closed.

v) Specific heat rate of kiln for calculating Notional energy of imported clinker-

should be based on GCV or NCV

DCs are required to submit the specific heat values of the assessment year in line

with data submission as per baseline year i.e., if the baseline calculation was done

with GCV, it remains as GCV in the assessment year and if it is NCV it remains as

NCV in the assessment year.

Regarding the specific heat value of imported Clinker, the same will be considered

as given below:

a. If any plant earlier reported Specific heat rate of imported Clinker in NCV, during

the assessment year also NCV will be considered for the equivalent amount of

imported clinker as reported in the base year. The extra amount of imported

clinker will be treated with heat rate value calculated in GCV basis of the

assessment year.

b. If there is any decrease in imported clinker, the present system will remain as it is

and does not call for any normalization factor.


vi) Normalization factor for CPP heat rate versus PLF

The committee decided to arrive at Normalization by using Heat and Mass Balance

Diagram (HMBD) of CPPs. BEE has requested that all the DCs having CPP should

send their respective HMBD to BEE and CII by 5 th April 2013 to work out this

normalization factor. Parallelly BEE will develop the normalization curve from the

data available with them.

vii) Normalization factor for raw material quality:

It was felt that the very rare possibility of change of raw material quality from baseline

to assessment year on account of adopting new mines. Since the form-1 does not

contain the base line raw material quality data and hence BEE expressed that it


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would be difficult to give correction factor in the first cycle. This normalisation factor

can come in the second cycle and the form-1 should be modified to collect the

burnability index and limestone hardness during the first PAT cycle assessment. The

committee accepted for not considering this normalization factor in the first cycle.

viii) Change of major product and change of clinker factor of the minor products

(Baseline period versus assessment year):

The baseline year major product will remain as major product in the calculation

during assessment year even in the cases where major product changes.

It has been decided that the PAT framework should encourage the increased use

of fly ash/ slag in cement.

The committee decided to write the formula in alpha numeric format such that it

is easy to understand.

The factors which are worked out are given below:

Probable Solutions

Baseline Major Product shall be considered as major product of Assessment year.

Case-1:

Baseline Major Product.PPC Assess. Year Major Product:OPC

Proposed Treatment:

Baseline Major Product shall be considered as major product of Assessment year.

BEE proposed formulae as given below:

Notional Energy (million kcal) = {[(A-B) xC xD] [(E -F) x G x H]}/10

A = Equivalent Major Cement production in assessment yearB= Reported cement production in assessment year

C= Electrical SEC of cement grinding (kWh/Ton of cement) for assessment

year

D= Weighted average CPP Heat/Grid Heat Rate (kcal/kWh) in the

assessment year

E= Equivalent Major Cement production in baseline period


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F= Reported cement production in baseline period

G= Electrical SEC of cement grinding (kWh/Tone of cement) for baseline

period

H= Weighted average CPP/Grid Heat Rate (kcal/kWh) for baseline period

The notional energy corrections calculated above will be added to the total

energy in the assessment year.

The calculation above has been substantiated in the working sheet,

enclosed.

Case-2:

Baseline Major Pr: OPC Assess. Yr. Major Pr: PPC

Proposed Treatment:

Notional Energy for Clinker Produced due to change in Additives/Clinker

Factor (Million kcal)

= J X [K x L + M x 1000]/10

J = Clinker produced due to change in Additives/Clinker Factor (Lakh Ton)

K=Electrical SEC (Up to Clinkerisation) (kwh/ton of cement) for assessment

year

L= Weighted Average Heat rate (kcal/kwh) for the assessment year

M=Thermal SEC of Clinker for assessment year (kcal/kg of clinker)

Where-

Clinker produced due to change in Additives/Clinker Factor (Lakh Ton)=

{N X (1-P)}-{QX (1-R)}

N= PPC production in assessment year (lakh Ton)

P= PPC Clinker factor in assessment year

Q= PPC production in baseline year (Lakh Ton)

R= PPC Clinker factor in baseline year

The notional energy corrections calculated above will be subtracted to the

total energy in the assessment year.

Additional Grinding Energy required to produce Additional PPC from Baseline shall


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be subtracted from total energy consumed as per BEE proposed formulae

(indicated above in case-1).

Case-3: Improvement in minor products clinker factor.

Baseline Major Pr.OPC Assess. Yr. Major Pr:OPC

Proposed Treatment:

Notional Energy for Clinker Produced due to change in Additives/Clinker

Factor (Million kcal)

= J X [K x L + M x 1000]/10

J = Clinker produced due to change in Additives/Clinker Factor (Lakh Ton)

K=Electrical SEC (Up to Clinkerisation) (kwh/ton of cement) for assessment

year

L= Weighted Average Heat rate (kcal/kwh) for the assessment year

M=Thermal SEC of Clinker for assessment year (kcal/kg of clinker)

Where-

Clinker produced due to change in Additives/Clinker Factor (Lakh Ton)=

{N X (1-P)}-{QX (1-R)}

N= PPC production in assessment year (lakh Ton)

P= PPC Clinker factor in assessment year

Q= PPC production in baseline year (Lakh Ton)

R= PPC Clinker factor in baseline year

The notional energy corrections calculated above will be subtracted to the

total energy in the assessment year.

Additional Grinding Energy required to produce Additional PPC from Baseline shall

be subtracted from total energy consumed as per BEE proposed formulae

(indicated above as in case 1).

The same has been substantiated along with working sheet, which is enclosed.

M/s Ultratech has suggested an alternate approach for the normalization factor for

above product mix change. The committee suggested to circulate BEE and Ultratech


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calculations to the members of the normalization committee. Members are requested

to reply by 10thApril 2013.

ix) Normalization of energy losses due to frequent outage and Power holiday of

the grid power:

Documentary evidence need to be submitted to the auditors during the assessment

to substantiate the claims of energy loss during hot to cold and cold to hot restarts

due to additional number of outages and Power holiday of grid from the baseline

year by the DCs. This will be exclusive of machine shut down and kiln stoppage on

account of excessive clinker stocks


x) Normalization for Non availability of Biomass

BEE will indicate the type of documentation required for the non availability of the

biomass in the assessment year. DCs should submit the support of the above claim

if DC wishes to claim the benefit of above normalization.


xi) Normalization for mandatory usage of industrial/municipal waste which arehaving adverse impact on specific thermal energy.

The DCs need to substantiate extent of energy loss due to the above issue with

proper calculation to BEE assessor during the assessment to claim the benefit of

above normalization. The energy loss will be deducted from the total energy in the

assessment year while calculating the SEC of the assessment year.


xii) Normalisation factor for use of raw slurry with variable moisture content

(Sriram Cement)

The DC has been advised to substantiate the moisture % in the raw slurry versus the

kiln heat rate, so that it can be normalized in the assessment year. It is essential that

the DC maintains the record to substantiate the increase in moisture. The data is

required for the baseline as well as for assessment year to avail the normalization.



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xiii) Differential Renewable Energy Import:

Some of the members have requested that the differential renewable energy

(Baseline vs assessment year) imported by the plant through their own renewable

energy generation unit with wheeling and banking arrangement or through a bilateral

agreement over and above the RPO obligation may be considered as 860 Kcal/KWh.

As per EC act, the same has been considered as input energy to the plant and will

be treated as it is.

BEE agrees to look into this correction factor and will consult and MNRE and legal

team and revert.

xiv) Fully or Partial plant / mines shutdown due to statutory directives during the

PAT cycle (20122015)

One of the DC has made a request to BEE to exempt from the PAT assessment or

reduce specific energy reduction target on pro rata basis for the period the plant was

in normal operation.

This issue is likely to get addressed parallel with the normalization factors for

Capacity utilization vs. Kiln Heat rate and normalization for change in raw material

quality. BEE will take legal opinion and revert back with this issue.

xv) Shree Cements request for considering the heat rate of 2400 Kcal/KwH for the

15MW of energy being imported from IPP:

The committee reviewed this request and asked Shree Cements to submit SLD

showing direct power supply to the cement plant from Shree mega power without

routing through grid.

3. The committee decided to get all relevant data and circulate to all DCs. After receiving

the comments from the DCs, the technical committee will finally submit their report to

sectoral committee.

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