boiler tune auto report

Recommendation

Background

We measured combustion gas temperatures and composition at several firing rates in order to establish

an accurate model for boiler operation. With the combustion gas analysis, we used the ASME indirect

method to calculate combustion efficiency for your boiler(s) at each firing rate. We then used the

operating hours that plant personnel provided to calculate annual fuel use for your boiler(s). We verified

the information that we measured, obtained from plant personnel, or assumed through boiler records or

logs to the extent possible. Finally, we compared the calculated boiler fuel use with your fuel bills to

verify the model is consistent with your operation.

Ideally, a boiler would use just enough combustion air to burn all of the fuel, with no excess air. Excess

air carries heat up the stack and reduces boiler efficiency. However, all burners require some excess air

to ensure complete combustion. We assume that you can operate your boiler with 4.0% excess oxygen

(O2). Depending on the boiler and control strategy it could be possible to reduce excess oxygen below

4.0% for additional savings, although care must be taken to ensure combustibles (unburned fuel) and

carbon monoxide (CO) concentrations do not rise to unacceptable levels.

* 1 MMBtu = 1,000,000 Btu, 1 therm = 100,000 Btu

(MMBtu)* (therm)* Savings Cost (Years)

Efficiency can also be improved by cleaning scale from the waterside heat transfer surfaces. Scale

deposits occur when calcium, magnesium, and silica, form a layer of material on the boiler heat

exchanger surfaces. By removing the scale, heat transfer will improve, lowering stack temperatures.

235.6 2,356.2

Implement a boiler tuning program to maintain an optimum air-fuel ratio, improving combustion

efficiency and lowering fuel use. Tuning your boiler(s) will reduce associated fuel consumption by

3.2%.

$2,534 $1,000

AR No. #

Boiler Tune

0.4

Assessment Recommendation Summary

Implementation PaybackEnergy Energy Cost

Proposal

Source: http://www.flickr.com/photos/anguskirk/

We recommend you have a boiler specialist tune your boiler to 4.0% exhaust O2 and clean your boiler

water side heat exchanger surfaces to increase combustion efficiency . We suggest this be done

immediately and then once every year after. We estimate a boiler tune will cost $500 per boiler. Annual

savings after deducting the annual cost to tune your boiler will be $2,534, paying for the initial

implementation cost of the first tuning in 0.4 years.

Energy Savings Summary Equations

Total Current Energy Use (CE) 7,269.0 MMBtu (Rf. 1) Eq. 1) Annual Energy Savings (ES )

Total Proposed Energy Use (PE) 7,033.4 MMBtu (Rf. 1)

Energy Savings (ES) 235.6 MMBtu (Eq. 1)

Eq. 2) Cost Savings (CS )

Implementation Cost Summary

Labor Costs

Number of Boilers to Tune (B) 2 Eq. 3) Implementation Costs (IC )

Labor Cost per Boiler (L) $500 (N. 1)

Economic Results

Cost Savings (CS) $2,534 (Eq. 2) References

Implementation Costs (IC) $1,000 (Eq. 3)

Payback (PB) 0.4 years

Notes

Boiler Tune

Rf. 1) Savings were calculated using the

Boiler Worksheet found on the following

pages.

N. 1) The boiler should be tuned immediately, and then once every year to maintain

optimum efficiency.

PECE

LBECES

LB

Percent

High Medium Low Standby High Medium Low Standby Savings

Boiler 1 71.4% 68.0% 60.8% 18.1% 73.3% 70.0% 62.7% 21.5% 2.9%

Boiler 2 78.3% - - - 81.1% - - - 3.4%

- - - - - - - - -

- - - - - - - - -

- - - - - - - - -

- - - - - - - - -

- - - - - - - - -

- - - - - - - - -

Total 3.2%

Total


Units (MMBtu) (MMBtu) (MMBtu) (MMBtu) (MMBtu) (MMBtu) (MMBtu) (MMBtu) (MMBtu)

Boiler 1 1,000.0 750.0 500.0 19.0 974.7 728.2 484.8 16.0 65.3

Boiler 2 5,000.0 - - - 4,829.7 - - - 170.3

- - - - - - - - 0.0

- - - - - - - - 0.0

- - - - - - - - 0.0

- - - - - - - - 0.0

- - - - - - - - 0.0

- - - - - - - - 0.0

Total 235.6

Total


Boiler 1 $15,000 $11,250 $7,500 $285 $14,621 $10,923 $7,272 $239 $980

Boiler 2 $75,000 - - - $72,446 - - - $2,554

- - - - - - - - $0

- - - - - - - - $0

- - - - - - - - $0

- - - - - - - - $0

- - - - - - - - $0

- - - - - - - - $0

Total $3,534$109,035 $105,501

Current Proposed

Cost Savings Summary

Current Proposed

7,269.0 7,033.4

Energy Savings Summary

Boiler Tune

Efficiency Summary

Current Proposed

3,100 hours

5.10 minutes 1 MMBtu/hr

30 seconds 20%

80oF 50

oF

75% 14.7 psia

0.01 lbv/lb air 0 feet

10 psi 6 ft3

0.1103 btu/(lbm-R)

Current Steam Pressure 100 psig 338oF

3.89 ft3/lb 309.0 btu/lbm

880.0 btu/lbm 1,189.0 btu/lbm

Proposed Steam Pressure 100 psig 338oF



$15.00 /MMBtu

81.80% C 0.00% S

18.20% H 0.00% N2

0.00% O2 0.00%

0.00% 21,670 btu/lbm

44.0 g/mol 4.00% O2

5.00% O2

806.9 4.84 minutes

5.10 minutes 0.25 minutes

Steam System Volume

Operating Hours

Inlet Air Temperature Inlet Water Temperature

Air Humidity Ratio

Purge Air Temperature Atmospheric Pressure

Steam Gas Constant

Pressure Range

Manufacturer

Control Type

Standby Cycle Time

Saturated Vapor Specific Volume Saturated Liquid Enthalpy

Evaporated Enthalpy

Propane Fuel Cost

Percent Carbon Percent Sulfur

Percent Hydrogen Percent Nitrogen

Fuel Type

Boiler Information

Enviromental Data

Steam System

Boiler Cycling

Current Steam Properties

Saturated Vapor Enthalpy

Moisture Content Higher Heating Value

Saturated Vapor Enthalpy

Saturated Vapor Specific Volume

Evaporated Enthalpy

Current Steam Temperature

Proposed Steam Properties

Proposed Steam Temperature

Saturated Liquid Enthalpy

Fuel Properties

Off Cycle

Run Cycle

Total Cycle

Percent Oxygen Percent Ash

Boiler Tune

Low/Standby Fire Proposed O2

Location Boiler 1

On-Off

Maximum Firing Rate

Minimum Firing RatePurge Cycle Time

Elevation

Molecular Weight High/Medium Fire Proposed O2

DPVh

High Medium Low Standby High Medium Low Standby

Energy Use

Percent Capacity 100% 75% 50% 19% 100% 75% 50% 19%

Fuel Input (MMBtu/hr) 1.00 0.75 0.50 0.19 0.97 0.73 0.48 0.16

Operating Hours 1,000 1,000 1,000 100 1,000 1,000 1,000 100

Energy Use (MMBtu/yr) 1,000.0 750.0 500.0 19.0 974.7 728.2 484.8 16.0

Stack Conditions

O2 10.0% 9.0% 8.0% 7.0% 4.0% 4.0% 5.0% 5.0%

CO2 8.5% 8.0% 7.5% 6.0% 11.2% 11.2% 10.5% 10.5%

CO 8 ppm 8 ppm 8 ppm 9 ppm 8 ppm 8 ppm 8 ppm 9 ppm

Stack Temperature 350.0 F 325.0 F 300.0 F 300.0 F 350.0 F 325.0 F 300.0 F 300.0 F

Net Stack Temperature 270.0 F 245.0 F 220.0 F 220.0 F 270.0 F 245.0 F 220.0 F 220.0 F

Mass Flow Rates

Fuel Flow Rate (lbm/min) 0.7691 0.5768 0.3846 0.1461 0.7497 0.5600 0.3729 0.1228

Air Flow Rate (lbm/min) 15.9230 11.5515 7.4589 2.7487 12.9457 9.6714 6.6186 2.1796

Efficiencies

Dry Gas Losses 7.13% 6.85% 6.54% 8.09% 5.47% 4.96% 4.72% 4.72%

Moisture Formation 8.77% 8.69% 8.60% 8.60% 8.77% 8.69% 8.60% 8.60%

Moisture in Fuel 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00%

Carbon Monoxide 0.00% 0.00% 0.00% 0.01% 0.00% 0.00% 0.00% 0.00%

Losses Due to Ash 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00%

Moisture in the Air 1.12% 1.07% 1.03% 0.99% 0.93% 0.92% 0.94% 0.94%

Combustion Efficiency 82.98% 83.39% 83.83% 82.31% 84.83% 85.43% 85.73% 85.73%

Thermal Losses 11.53% 15.38% 23.07% 60.71% 11.53% 15.38% 23.07% 60.71%

Cycling Losses - - - 3.49% - - - 3.48%

Boiler Efficiency 71.4% 68.0% 60.8% 18.1% 73.3% 70.0% 62.7% 21.5%

Notes

Boiler Efficiency

Boiler Tune

We calculate combustion efficiencies from the combustion gas conditions we measured using the ASME indirect

method. We then calculate boiler efficiencies including radiation, convection and cycling losses. For more detailed

information regarding how efficiency losses are calculated, refer to the Boiler Appendix.

Current Proposed

1,000 hours

0.97 minutes 5 MMBtu/hr

30 seconds 20%

80oF 50

oF

75% 14.7 psia


10 psi 30 ft3

0.1103 btu/(lbm-R)







$15.00 /MMBtu

81.80% C 0.00% S

18.20% H 0.00% N2

0.00% O2 0.00%

0.00% 21,670 btu/lbm

44.0 g/mol 4.00% O2

5.00% O2

4,034.6 0.48 minutes

0.97 minutes 0.48 minutes

Boiler Tune

Boiler Information

Manufacturer Location Boiler 2

Air Humidity Ratio Elevation

Control Type Full Modulating Operating Hours

Standby Cycle Time Maximum Firing Rate

Purge Cycle Time Minimum Firing Rate

Enviromental Data




Steam System

Pressure Range Steam System Volume

Steam Gas Constant




Evaporated Enthalpy Saturated Vapor Enthalpy





Fuel Properties

Fuel Type Propane Fuel Cost






Boiler Cycling

DPVh Run Cycle

Off Cycle Total Cycle


Energy Use


Fuel Input (MMBtu/hr) 5.00 - - - 4.83 - - -

Operating Hours 1,000 0 0 0 1,000 0 0 0

Energy Use (MMBtu/yr) 5,000.0 - - - 4,829.7 - - -

Stack Conditions

O2 10.0% - - - 4.0% - - -

CO2 7.5% - - - 11.2% - - -

CO 5 ppm - - - 5 ppm - - -

Stack Temperature 350.0 F - - - 350.0 F - - -

Net Stack Temperature 270.0 F - - - 270.0 F - - -

Mass Flow Rates

Fuel Flow Rate (lbm/min) 3.8456 - - - 3.7146 - - -

Air Flow Rate (lbm/min) 79.6152 - - - 64.1469 - - -

Efficiencies

Dry Gas Losses 8.04% - - - 5.47% - - -

Moisture Formation 8.77% - - - 8.77% - - -

Moisture in Fuel 0.00% - - - 0.00% - - -

Carbon Monoxide 0.00% - - - 0.00% - - -

Losses Due to Ash 0.00% - - - 0.00% - - -

Moisture in the Air 1.12% - - - 0.93% - - -

Combustion Efficiency 82.07% - - - 84.83% - - -

Thermal Losses 3.73% - - - 3.73% - - -

Cycling Losses - - - - - - - -

Boiler Efficiency 78.3% - - - 81.1% - - -

Notes




Boiler Tune

Boiler Efficiency

Current Proposed

0 hours

#DIV/0! minutes MMBtu/hr

30 seconds 20%

80oF 50

oF

75% 14.7 psia


10 psi 0 ft3

0.1103 btu/(lbm-R)







/MMBtu

#N/A C #N/A S

#N/A H #N/A N2

#N/A O2 #N/A

#N/A #N/A btu/lbm

#N/A g/mol #N/A O2

#N/A O2

0.0 #DIV/0! minutes

#DIV/0! minutes #DIV/0! minutes

Boiler Tune

Boiler Information

Manufacturer Location


Control Type Operating Hours



Enviromental Data




Steam System


Steam Gas Constant









Fuel Properties

Fuel Type Fuel Cost






Boiler Cycling

DPVh Run Cycle



Energy Use


Fuel Input (MMBtu/hr) - - - - - - - -

Operating Hours 0 0 0 0 0 0 0 0

Energy Use (MMBtu/yr) - - - - - - - -

Stack Conditions

O2 - - - - - - - -

CO2 - - - - - - - -

CO - - - - - - - -

Stack Temperature - - - - - - - -

Net Stack Temperature - - - - - - - -

Mass Flow Rates

Fuel Flow Rate (lbm/min) - - - - - - - -

Air Flow Rate (lbm/min) - - - - - - - -

Efficiencies

Dry Gas Losses - - - - - - - -

Moisture Formation - - - - - - - -

Moisture in Fuel - - - - - - - -

Carbon Monoxide - - - - - - - -

Losses Due to Ash - - - - - - - -

Moisture in the Air - - - - - - - -

Combustion Efficiency - - - - - - - -

Thermal Losses - - - - - - - -


Boiler Efficiency - - - - - - - -

Notes




Boiler Tune

Boiler Efficiency

Current Proposed

0 hours


seconds

oF

oF

14.7 psia

lbv/lb air feet

psi 0 ft3

0.1103 btu/(lbm-R)

Current Steam Pressure psig 212oF



Proposed Steam Pressure psig 212oF



/MMBtu

#N/A C #N/A S

#N/A H #N/A N2

#N/A O2 #N/A

#N/A #N/A btu/lbm

#N/A g/mol #N/A O2

#N/A O2

0.0 #DIV/0! minutes


Boiler Tune

Boiler Information






Enviromental Data




Steam System


Steam Gas Constant









Fuel Properties

Fuel Type Fuel Cost






Boiler Cycling

DPVh Run Cycle
