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Tulsa Heaters Midstream 2
FiredHeaterEfficiency
“Why is the efficiency of my
fired heater important?”
Because inefficient ...
Tulsa Heaters Midstream 3
MeasuringFired
HeaterEfficiency
This guide will teach you the
process of measuring and
calculati...
Whatdowemeanby“efficiency”?
Tulsa Heaters Midstream 5
ThermalVSFuelEfficiency
THERMAL EFFICIENCY
- total heat absorbed divided by total heat input
FUE...
Tulsa Heaters Midstream 6
EquipmentNeeded
• Temperature-measuring devices, such as
thermocouples or thermometers, to
measu...
Tulsa Heaters Midstream 7
BeforetheTest
Establish and maintain operating conditions
Select and calibrate instrumentation
P...
Tulsa Heaters Midstream 8
Testing
Test procedure:
Measurements:
• The heater shall be operated at a uniform rate throughou...
Tulsa Heaters Midstream 10
Example
Hot oil heater for gas plant Ambient air temperature: 70°F
Relative humidity: 50%
Fuel ...
Tulsa Heaters Midstream 11
ThermalEfficiency
Where:
ℎ 𝐿 lower heating value of the fuel (Btu/lb)
∆ℎ 𝑎 heat correction due ...
Needtosolveforallvariables
Step1:
solve for heat loss through the stack (ℎ 𝑠)
Tulsa Heaters Midstream 14
CombustionWorksheet
Fuel
Component
Column 1
Volume
fraction
%
Nitrogen 1.61
Carbon
dioxide
0.15...
Tulsa Heaters Midstream 15
CombustionWorksheet
Fuel
Component
Column 1
Volume
fraction
%
Column 2
Relative
molecular
mass
...
Tulsa Heaters Midstream 16
CombustionWorksheet
Fuel
Component
Column 1
Volume
fraction
%
Column 2
Relative
molecular
mass
...
Tulsa Heaters Midstream 17
CompletedCombustionWorksheet
Fuel
Component
Column 1
Volume
fraction
%
Column 2
Relative
molecu...
Tulsa Heaters Midstream 18
RelativeHumidity
Correction for relative humidity:
where:
𝑃vapor vapor pressure of water at amb...
Tulsa Heaters Midstream 19
RelativeHumidity
Correction for relative humidity:
where:
𝑃vapor vapor pressure of water at amb...
Tulsa Heaters Midstream 20
RelativeHumidity
Correction for relative humidity:
where:
𝑃vapor vapor pressure of water at amb...
Tulsa Heaters Midstream 21
RelativeHumidity
Correction for relative humidity:
where:
𝑃vapor vapor pressure of water at amb...
Tulsa Heaters Midstream 22
RelativeHumidity
Correction for relative humidity:
where:
𝑃vapor vapor pressure of water at amb...
Tulsa Heaters Midstream 23
ExcessAir
Correction for excess air:
=
(28.85 × %O2)(
N2 formed
28
+
CO2 formed
44
+
H2O formed...
Tulsa Heaters Midstream 24
ExcessAir
Correction for excess air:
=
(28.85 × %O2)(
N2 formed
28
+
CO2 formed
44
+
H2O formed...
Tulsa Heaters Midstream 25
=
lb of excess air per lb of fuel
air required
× 100
ExcessAir
Correction for excess air:
=
(28...
Tulsa Heaters Midstream 26
=
lb of excess air per lb of fuel
air required
× 100
ExcessAir
Correction for excess air:
=
(28...
Tulsa Heaters Midstream 27
StackLoss
Component
Column 1
Component formed
(lb per lb of fuel)
Carbon dioxide 2.65
Water vap...
Tulsa Heaters Midstream 28
StackLoss
Component
Column 1
Component formed
(lb per lb of fuel)
Column 2
Enthalpy at T
(Btu/l...
Tulsa Heaters Midstream 29
StackLoss
Component
Column 1
Component formed
(lb per lb of fuel)
Column 2
Enthalpy at T
(Btu/l...
Step2:
solve for additional heat losses
Tulsa Heaters Midstream 31
ThermalEfficiency
Where:
ℎ 𝐿 lower heating value of the fuel (Btu/lb)
∆ℎ 𝑎 heat correction due ...
Tulsa Heaters Midstream 32
HeatLosses
Heat loss due to air:
∆ℎ 𝑎 = 𝑐 𝑝a × (𝑇𝑎 − 𝑇𝑑) × ( 𝑚 𝑎 𝑚 𝑓)
where:
𝑐 𝑝a specific heat...
Tulsa Heaters Midstream 33
HeatLosses
Heat loss due to fuel gas:
∆ℎ 𝑓 = 𝑐 𝑝fuel × (𝑇𝑓 − 𝑇𝑑)
where:
𝑐 𝑝fuel specific heat o...
Tulsa Heaters Midstream 34
HeatLosses
Heat loss due to atomization medium:
∆ℎ 𝑚 = ∆𝐸 × ( 𝑚 𝑠𝑡 𝑚 𝑓)
where:
∆𝐸 enthalpy diff...
Tulsa Heaters Midstream 35
RadiationLosses
Heat loss due to radiation:
ℎ 𝑟 = ℎ 𝐿 × %radiation loss ℎ 𝑟 = 20,814 × 0.015
ℎ ...
Step3:
solve for thermal and fuel efficiencies
Tulsa Heaters Midstream 37
ThermalEfficiency
Where:
ℎ 𝐿 20,814 Btu/lb
∆ℎ 𝑎 46.37 Btu/lb
∆ℎ 𝑓 23.47 Btu/lb
∆ℎ 𝑚 0 Btu/lb
ℎ ...
Tulsa Heaters Midstream 38
ThermalEfficiency
Where:
ℎ 𝐿 20,814 Btu/lb
∆ℎ 𝑎 46.37 Btu/lb
∆ℎ 𝑓 23.47 Btu/lb
∆ℎ 𝑚 0 Btu/lb
ℎ ...
Tulsa Heaters Midstream 39
FuelEfficiency
Where:
ℎ 𝐿 20,814 Btu/lb
∆ℎ 𝑎 46.37 Btu/lb
∆ℎ 𝑓 23.47 Btu/lb
∆ℎ 𝑚 0 Btu/lb
ℎ 𝑟 3...
Tulsa Heaters Midstream 40
FuelEfficiency
Where:
ℎ 𝐿 20,814 Btu/lb
∆ℎ 𝑎 46.37 Btu/lb
∆ℎ 𝑓 23.47 Btu/lb
∆ℎ 𝑚 0 Btu/lb
ℎ 𝑟 3...
* Based on $2.75/MMBtu gas price
Tulsa Heaters Midstream 42
Conclusion
Knowing how to check your heater’s efficiency gives you the
knowledge and power to i...
Tulsa Heaters Midstream 43
Want to learn more?
Check out our other resources
RESOURCES
Follow us:
www.tulsaheatersmidstrea...
Fired Heater Efficiency Guide
Fired Heater Efficiency Guide
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Fired Heater Efficiency Guide

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Learn the API 560 method for measuring and calculating the efficiency of a fired heater.

Published in: Engineering
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Fired Heater Efficiency Guide

  1. 1. Tulsa Heaters Midstream 2 FiredHeaterEfficiency “Why is the efficiency of my fired heater important?” Because inefficient heaters cost you money!
  2. 2. Tulsa Heaters Midstream 3 MeasuringFired HeaterEfficiency This guide will teach you the process of measuring and calculating your heater’s efficiency – so you can optimize your plant and save money. • Based on method outlined in API 560 Annex G • Procedure intended for fired heaters burning liquid or gaseous fuels. Not recommended for solid fuels.
  3. 3. Whatdowemeanby“efficiency”?
  4. 4. Tulsa Heaters Midstream 5 ThermalVSFuelEfficiency THERMAL EFFICIENCY - total heat absorbed divided by total heat input FUEL EFFICIENCY - total heat absorbed divided by heat input derived from the combustion of the fuel only NOTE: this definition differs from the traditional definition of fired heater efficiency, which generally refers to fuel efficiency
  5. 5. Tulsa Heaters Midstream 6 EquipmentNeeded • Temperature-measuring devices, such as thermocouples or thermometers, to measure the temperature of: • Fuel • Ambient air • Atomizing medium (if applicable) • Flue gas • Thermal fluid • Flue-gas analytical devices to measure oxygen and combustible gases
  6. 6. Tulsa Heaters Midstream 7 BeforetheTest Establish and maintain operating conditions Select and calibrate instrumentation Perform any re-rating necessary to account for differences between design and test conditions Ensure fuel is acceptable for the test Ensure heater is operating properly with respect to the size and shape of flame, excess air & draught
  7. 7. Tulsa Heaters Midstream 8 Testing Test procedure: Measurements: • The heater shall be operated at a uniform rate throughout the test • Data shall be taken at the start of the test, and every 2 hours thereafter • The duration of the test shall extend until three consecutive sets of collected data fall within the prescribed limits • Fuel gas quantity and heating value • Flue-gas temperature and composition analysis
  8. 8. Tulsa Heaters Midstream 10 Example Hot oil heater for gas plant Ambient air temperature: 70°F Relative humidity: 50% Fuel gas composition (vol%): • Nitrogen – 1.61 • Carbon dioxide – 0.15 • Methane – 98.17 • Ethane – 0.008 Fuel gas LHV • 20,814 Btu/lb Fuel gas HHV • 23,115 Btu/lb Fuel gas temperature • 100°F Fuel gas pressure • 50 psig Excess Oxygen: 3% (dry) Radiation heat loss: 1.5%
  9. 9. Tulsa Heaters Midstream 11 ThermalEfficiency Where: ℎ 𝐿 lower heating value of the fuel (Btu/lb) ∆ℎ 𝑎 heat correction due to air (Btu/lb) ∆ℎ 𝑓 heat correction due to fuel (Btu/lb) ∆ℎ 𝑚 heat correction due to atomizing medium (Btu/lb) ℎ 𝑟 assumed radiation heat loss (Btu/lb) ℎ 𝑠 calculated stack heat loss (Btu/lb) 𝒆 = 𝒉 𝑳 + ∆𝒉 𝒂 + ∆𝒉 𝒇 + ∆𝒉 𝒎 − (𝒉 𝒓 + 𝒉 𝒔 𝒉 𝑳 + ∆𝒉 𝒂 + ∆𝒉 𝒇 + ∆𝒉 𝒎 × 𝟏𝟎𝟎
  10. 10. Needtosolveforallvariables
  11. 11. Step1: solve for heat loss through the stack (ℎ 𝑠)
  12. 12. Tulsa Heaters Midstream 14 CombustionWorksheet Fuel Component Column 1 Volume fraction % Nitrogen 1.61 Carbon dioxide 0.15 Methane 98.17 Ethane 0.08 TOTAL - Total per pound of fuel - Insert fuel composition into combustion worksheet
  13. 13. Tulsa Heaters Midstream 15 CombustionWorksheet Fuel Component Column 1 Volume fraction % Column 2 Relative molecular mass Column 3 (1x2) Total mass (lb) Column 4 Net heating value (Btu/lb) Column 5 (3x4) Heating value (Btu) Nitrogen 1.61 28.0 0.4508 - - Carbon dioxide 0.15 44.0 0.066 - - Methane 98.17 16.0 15.70 21,500 337,704.80 Ethane 0.08 30.1 0.02 20,420 491.71 TOTAL - - 16.25 - 338,196.51 Total per pound of fuel - - - - 20,814.55 (5) Calculate total mass and heating value of fuel
  14. 14. Tulsa Heaters Midstream 16 CombustionWorksheet Fuel Component Column 1 Volume fraction % Column 2 Relative molecular mass Column 3 (1x2) Total mass (lb) Column 4 Net heating value (Btu/lb) Column 5 (3x4) Heating value (Btu) Column 6 Air required (lb air/lb) Column 7 (3x6) Air required (lbs) Column 8 CO2 formed (lbs CO2/lb) Column 9 (3x8) CO2 formed (lbs) Column 10 H2O formed (lbs H2O/lb) Column 11 (3x10) H2O formed (lbs) Column 12 N2 formed (lbs N2/lb) Column 13 (3x12) N2 formed (lbs) Nitrogen 1.61 28.0 0.4508 - - - - - - - - - - Carbon dioxide 0.15 44.0 0.066 - - - - - - - - - - Methane 98.17 16.0 15.70 21,500 337,704.80 17.24 270.79 2.74 43.04 2.25 35.34 13.25 208.12 Ethane 0.08 30.1 0.02 20,420 491.71 16.09 0.39 2.93 0.07 1.80 0.04 12.37 0.30 TOTAL - - 16.25 - 338,196.51 - 271.18 - 43.11 - 35.38 - 208.42 Total per pound of fuel - - - - 20,814.55 - 16.69 - 2.65 - 2.18 - 12.83 (5) (7) (9) (11) (13) Calculate products of combustion for fuel
  15. 15. Tulsa Heaters Midstream 17 CompletedCombustionWorksheet Fuel Component Column 1 Volume fraction % Column 2 Relative molecular mass Column 3 (1x2) Total mass Column 4 Net heating value (Btu/lb) Column 5 (3x4) Heating value (Btu) Column 6 Air required (lb air/lb) Column 7 (3x6) Air required (lbs) Column 8 CO2 formed (lbs CO2/lb) Column 9 (3x8) CO2 formed (lbs) Column 10 H2O formed (lbs H2O/lb) Column 11 (3x10) H2O formed (lbs) Column 12 N2 formed (lbs N2/lb) Column 13 (3x12) N2 formed (lbs) Nitrogen 1.61 28.0 0.4508 - - - - - - - - - - Carbon dioxide 0.15 44.0 0.066 - - - - - - - - - - Methane 98.17 16.0 15.70 21,500 337,704.80 17.24 270.79 2.74 43.04 2.25 35.34 13.25 208.12 Ethane 0.08 30.1 0.02 20,420 491.71 16.09 0.39 2.93 0.07 1.80 0.04 12.37 0.30 TOTAL - - 16.25 - 338,196.51 - 271.18 - 43.11 - 35.38 - 208.42 Total per pound of fuel - - - - 20,814.55 - 16.69 - 2.65 - 2.18 - 12.83 (5) (7) (9) (11) (13)
  16. 16. Tulsa Heaters Midstream 18 RelativeHumidity Correction for relative humidity: where: 𝑃vapor vapor pressure of water at ambient temperature (from steam tables) 𝑃air 14.696 psi = 𝑃vapor 𝑃air × 𝑅𝐻 100 × 18 28.85 moisture in air
  17. 17. Tulsa Heaters Midstream 19 RelativeHumidity Correction for relative humidity: where: 𝑃vapor vapor pressure of water at ambient temperature (from steam tables) 𝑃air 14.696 psi = 𝑃vapor 𝑃air × 𝑅𝐻 100 × 18 28.85 moisture in air = 0.364 14.696 × 50 100 × 18 28.85 = 0.0077 lbs of moisture per lb of air (a)
  18. 18. Tulsa Heaters Midstream 20 RelativeHumidity Correction for relative humidity: where: 𝑃vapor vapor pressure of water at ambient temperature (from steam tables) 𝑃air 14.696 psi = 𝑃vapor 𝑃air × 𝑅𝐻 100 × 18 28.85 moisture in air = 0.364 14.696 × 50 100 × 18 28.85 = 0.0077 lbs of moisture per lb of air (a) = air required 1 − moisture in air(a) (7) = 16.82 lbs of wet air per lb of fuel = 16.69 1 − 0.0077 (b)
  19. 19. Tulsa Heaters Midstream 21 RelativeHumidity Correction for relative humidity: where: 𝑃vapor vapor pressure of water at ambient temperature (from steam tables) 𝑃air 14.696 psi = 𝑃vapor 𝑃air × 𝑅𝐻 100 × 18 28.85 moisture in air = 0.364 14.696 × 50 100 × 18 28.85 = 0.0077 lbs of moisture per lb of air (a) = air required 1 − moisture in air(a) (7) = 16.82 lbs of wet air per lb of fuel = 16.69 1 − 0.0077 (b) = lbs wet air per lb of fuel(b) – air required(7) = 0.1295 lbs of moisture per lb of fuel (c) = 16.82 – 16.69
  20. 20. Tulsa Heaters Midstream 22 RelativeHumidity Correction for relative humidity: where: 𝑃vapor vapor pressure of water at ambient temperature (from steam tables) 𝑃air 14.696 psi = 𝑃vapor 𝑃air × 𝑅𝐻 100 × 18 28.85 moisture in air = 0.364 14.696 × 50 100 × 18 28.85 = 0.0077 lbs of moisture per lb of air (a) = air required 1 − moisture in air(a) (7) = 16.82 lbs of wet air per lb of fuel = 16.69 1 − 0.0077 (b) = lbs wet air per lb of fuel(b) – air required(7) = 0.1295 lbs of moisture per lb of fuel (c) = H2O formed(11) + lbs of moisture per lb of fuel(c) + atomizing steam = 2.31 lbs of H2O per lb of fuel (d) = 2.17 + 0.1295 + 0 = 16.82 – 16.69
  21. 21. Tulsa Heaters Midstream 23 ExcessAir Correction for excess air: = (28.85 × %O2)( N2 formed 28 + CO2 formed 44 + H2O formed 18 ) 20.95 − %O2[ 1.6028 × lbs H2O lbs air required + 1] lb excess air per lb of fuel NOTE: If oxygen samples are extracted on a dry basis, a value of zero shall be inserted for line (e) where a value is required from lines (c) and (d). If oxygen samples are extracted on a wet basis, the appropriate calculated value shall be inserted.
  22. 22. Tulsa Heaters Midstream 24 ExcessAir Correction for excess air: = (28.85 × %O2)( N2 formed 28 + CO2 formed 44 + H2O formed 18 ) 20.95 − %O2[ 1.6028 × lbs H2O lbs air required + 1] lb excess air per lb of fuel NOTE: If oxygen samples are extracted on a dry basis, a value of zero shall be inserted for line (e) where a value is required from lines (c) and (d). If oxygen samples are extracted on a wet basis, the appropriate calculated value shall be inserted. = (28.85 × %O2)( N2 formed 28 + CO2 formed 44 + H2O formed 18 ) 20.95 − %O2[ 1.6028 × lbs H2O lbs air required + 1] (13) (9) (d) (c) (7) = (28.85 × 3)( 12.83 28 + 2.65 44 + 0 18 ) 20.95 − 3[ 1.6028 × 0 16.69 + 1] = 2.50 lbs of excess air per lb of fuel (e)
  23. 23. Tulsa Heaters Midstream 25 = lb of excess air per lb of fuel air required × 100 ExcessAir Correction for excess air: = (28.85 × %O2)( N2 formed 28 + CO2 formed 44 + H2O formed 18 ) 20.95 − %O2[ 1.6028 × lbs H2O lbs air required + 1] lb excess air per lb of fuel NOTE: If oxygen samples are extracted on a dry basis, a value of zero shall be inserted for line (e) where a value is required from lines (c) and (d). If oxygen samples are extracted on a wet basis, the appropriate calculated value shall be inserted. = (28.85 × %O2)( N2 formed 28 + CO2 formed 44 + H2O formed 18 ) 20.95 − %O2[ 1.6028 × lbs H2O lbs air required + 1] (13) (9) (d) (c) (7) = (28.85 × 3)( 12.83 28 + 2.65 44 + 0 18 ) 20.95 − 3[ 1.6028 × 0 16.69 + 1] = 2.50 lbs of excess air per lb of fuel (e) (7) (e) = 2.50 16.69 × 100 = 14.98 lbs excess air (f)
  24. 24. Tulsa Heaters Midstream 26 = lb of excess air per lb of fuel air required × 100 ExcessAir Correction for excess air: = (28.85 × %O2)( N2 formed 28 + CO2 formed 44 + H2O formed 18 ) 20.95 − %O2[ 1.6028 × lbs H2O lbs air required + 1] lb excess air per lb of fuel NOTE: If oxygen samples are extracted on a dry basis, a value of zero shall be inserted for line (e) where a value is required from lines (c) and (d). If oxygen samples are extracted on a wet basis, the appropriate calculated value shall be inserted. = (28.85 × %O2)( N2 formed 28 + CO2 formed 44 + H2O formed 18 ) 20.95 − %O2[ 1.6028 × lbs H2O lbs air required + 1] (13) (9) (d) (c) (7) = (28.85 × 3)( 12.83 28 + 2.65 44 + 0 18 ) 20.95 − 3[ 1.6028 × 0 16.69 + 1] = 2.50 lbs of excess air per lb of fuel (e) = percent excess air 100 × lbs moisture per lb fuel + lb H2O per lb fuel (7) (e) = 2.50 16.69 × 100 = 14.98 lbs excess air (f) (f) (c) (d) = 14.98 100 × 0.1295 + 2.31 = 2.33 total lbs H2O per lb of fuel (corrected for excess air) (g)
  25. 25. Tulsa Heaters Midstream 27 StackLoss Component Column 1 Component formed (lb per lb of fuel) Carbon dioxide 2.65 Water vapor 2.33 Nitrogen 12.83 Air 2.50 Total 20.31 (9) from combustion worksheet (13) from combustion worksheet (g) from excess air worksheet (e) from excess air worksheet
  26. 26. Tulsa Heaters Midstream 28 StackLoss Component Column 1 Component formed (lb per lb of fuel) Column 2 Enthalpy at T (Btu/lb formed) Carbon dioxide 2.65 100 Water vapor 2.33 192 Nitrogen 12.83 120 Air 2.50 110 Total 20.31 - Exit flue-gas temperature, 𝑇𝑒: 500°F Values taken from enthalpy tables in API 560, Figures G.6 and G.7 for each flue-gas component
  27. 27. Tulsa Heaters Midstream 29 StackLoss Component Column 1 Component formed (lb per lb of fuel) Column 2 Enthalpy at T (Btu/lb formed) Column 3 Heat content (Btu/lb of fuel) Carbon dioxide 2.65 100 265.31 Water vapor 2.33 192 446.72 Nitrogen 12.83 120 1,539.27 Air 2.50 110 274.98 Total 20.31 - 2,526.28 Exit flue-gas temperature, 𝑇𝑒: 500°F ℎ 𝑠 = heat content at 𝑇𝑒 = 2,526.28 Btu/lb of fuel
  28. 28. Step2: solve for additional heat losses
  29. 29. Tulsa Heaters Midstream 31 ThermalEfficiency Where: ℎ 𝐿 lower heating value of the fuel (Btu/lb) ∆ℎ 𝑎 heat correction due to air (Btu/lb) ∆ℎ 𝑓 heat correction due to fuel (Btu/lb) ∆ℎ 𝑚 heat correction due to atomizing medium (Btu/lb) ℎ 𝑟 assumed radiation heat loss (Btu/lb) ℎ 𝑠 calculated stack heat loss (Btu/lb) 𝒆 = 𝒉 𝑳 + ∆𝒉 𝒂 + ∆𝒉 𝒇 + ∆𝒉 𝒎 − (𝒉 𝒓 + 𝒉 𝒔 𝒉 𝑳 + ∆𝒉 𝒂 + ∆𝒉 𝒇 + ∆𝒉 𝒎 × 𝟏𝟎𝟎
  30. 30. Tulsa Heaters Midstream 32 HeatLosses Heat loss due to air: ∆ℎ 𝑎 = 𝑐 𝑝a × (𝑇𝑎 − 𝑇𝑑) × ( 𝑚 𝑎 𝑚 𝑓) where: 𝑐 𝑝a specific heat of air 𝑇𝑎 temperature of air (°F) 𝑇𝑑 temperature of design air (°F) 𝑚 𝑎 𝑚 𝑓 the sum of 𝑚 𝑎 and 𝑚 𝑓, expressed as pounds of air per pound of fuel (from lines (b) and (e) on the excess air and relative humidity work sheet) = 𝑐 𝑝a × (𝑇𝑎 − 𝑇𝑑) × ( 𝑚 𝑎 𝑚 𝑓) = 0.24 × (70 − 60) × (16.81 + 2.50) ∆ℎ 𝑎 = 46.37 Btu/lb
  31. 31. Tulsa Heaters Midstream 33 HeatLosses Heat loss due to fuel gas: ∆ℎ 𝑓 = 𝑐 𝑝fuel × (𝑇𝑓 − 𝑇𝑑) where: 𝑐 𝑝fuel specific heat of fuel gas 𝑇𝑓 temperature of fuel gas (°F) 𝑇𝑑 temperature of design fuel gas (°F) = 𝑐 𝑝fuel × (𝑇𝑓 − 𝑇𝑑) = 0.587 × (100 − 60) ∆ℎ 𝑓 = 23.47 Btu/lb
  32. 32. Tulsa Heaters Midstream 34 HeatLosses Heat loss due to atomization medium: ∆ℎ 𝑚 = ∆𝐸 × ( 𝑚 𝑠𝑡 𝑚 𝑓) where: ∆𝐸 enthalpy difference 𝑚 𝑠𝑡 mass of steam (lb) No atomization steam in this case. ∆ℎ 𝑚 = 0
  33. 33. Tulsa Heaters Midstream 35 RadiationLosses Heat loss due to radiation: ℎ 𝑟 = ℎ 𝐿 × %radiation loss ℎ 𝑟 = 20,814 × 0.015 ℎ 𝑟 = 312.24 Btu/lb
  34. 34. Step3: solve for thermal and fuel efficiencies
  35. 35. Tulsa Heaters Midstream 37 ThermalEfficiency Where: ℎ 𝐿 20,814 Btu/lb ∆ℎ 𝑎 46.37 Btu/lb ∆ℎ 𝑓 23.47 Btu/lb ∆ℎ 𝑚 0 Btu/lb ℎ 𝑟 312.24 Btu/lb ℎ 𝑠 2,526.28 Btu/lb 𝒆 = 𝒉 𝑳 + ∆𝒉 𝒂 + ∆𝒉 𝒇 + ∆𝒉 𝒎 − (𝒉 𝒓 + 𝒉 𝒔 𝒉 𝑳 + ∆𝒉 𝒂 + ∆𝒉 𝒇 + ∆𝒉 𝒎 × 𝟏𝟎𝟎
  36. 36. Tulsa Heaters Midstream 38 ThermalEfficiency Where: ℎ 𝐿 20,814 Btu/lb ∆ℎ 𝑎 46.37 Btu/lb ∆ℎ 𝑓 23.47 Btu/lb ∆ℎ 𝑚 0 Btu/lb ℎ 𝑟 312.24 Btu/lb ℎ 𝑠 2,526.28 Btu/lb 𝒆 = 𝒉 𝑳 + ∆𝒉 𝒂 + ∆𝒉 𝒇 + ∆𝒉 𝒎 − (𝒉 𝒓 + 𝒉 𝒔 𝒉 𝑳 + ∆𝒉 𝒂 + ∆𝒉 𝒇 + ∆𝒉 𝒎 × 𝟏𝟎𝟎 𝒆 = 𝒉 𝑳 + ∆𝒉 𝒂 + ∆𝒉 𝒇 + ∆𝒉 𝒎 − (𝒉 𝒓 + 𝒉 𝒔 𝒉 𝑳 + ∆𝒉 𝒂 + ∆𝒉 𝒇 + ∆𝒉 𝒎 × 𝟏𝟎𝟎 𝒆 = )𝟐𝟎, 𝟖𝟏𝟒 + 𝟒𝟔. 𝟑𝟕 + 𝟐𝟑. 𝟒𝟕 + 𝟎 − (𝟑𝟏𝟐. 𝟐𝟒 + 𝟐, 𝟓𝟐𝟔. 𝟐𝟖 𝟐𝟎, 𝟖𝟏𝟒 + 𝟒𝟔. 𝟑𝟕 + 𝟐𝟑. 𝟒𝟕 + 𝟎 × 𝟏𝟎𝟎 𝒆 = 86.4%
  37. 37. Tulsa Heaters Midstream 39 FuelEfficiency Where: ℎ 𝐿 20,814 Btu/lb ∆ℎ 𝑎 46.37 Btu/lb ∆ℎ 𝑓 23.47 Btu/lb ∆ℎ 𝑚 0 Btu/lb ℎ 𝑟 312.24 Btu/lb ℎ 𝑠 2,526.28 Btu/lb 𝒆 𝒇 = 𝒉 𝑳 + ∆𝒉 𝒂 + ∆𝒉 𝒇 + ∆𝒉 𝒎 − (𝒉 𝒓 + 𝒉 𝒔 𝒉 𝑳 × 𝟏𝟎𝟎
  38. 38. Tulsa Heaters Midstream 40 FuelEfficiency Where: ℎ 𝐿 20,814 Btu/lb ∆ℎ 𝑎 46.37 Btu/lb ∆ℎ 𝑓 23.47 Btu/lb ∆ℎ 𝑚 0 Btu/lb ℎ 𝑟 312.24 Btu/lb ℎ 𝑠 2,526.28 Btu/lb 𝒆 𝒇 = 𝒉 𝑳 + ∆𝒉 𝒂 + ∆𝒉 𝒇 + ∆𝒉 𝒎 − (𝒉 𝒓 + 𝒉 𝒔 𝒉 𝑳 × 𝟏𝟎𝟎 𝒆 𝒇 = 𝒉 𝑳 + ∆𝒉 𝒂 + ∆𝒉 𝒇 + ∆𝒉 𝒎 − (𝒉 𝒓 + 𝒉 𝒔 𝒉 𝑳 × 𝟏𝟎𝟎 𝒆 𝒇 = )𝟐𝟎, 𝟖𝟏𝟒 + 𝟒𝟔. 𝟑𝟕 + 𝟐𝟑. 𝟒𝟕 + 𝟎 − (𝟑𝟏𝟐. 𝟐𝟒 + 𝟐, 𝟓𝟐𝟔. 𝟐𝟖 𝟐𝟎, 𝟖𝟏𝟒 × 𝟏𝟎𝟎 𝒆 𝒇 = 86.7%
  39. 39. * Based on $2.75/MMBtu gas price
  40. 40. Tulsa Heaters Midstream 42 Conclusion Knowing how to check your heater’s efficiency gives you the knowledge and power to improve your facility and optimize your heater. As we have seen, improving efficiency can help save your facility a lot of money. What are you waiting for? Go check and start saving now!
  41. 41. Tulsa Heaters Midstream 43 Want to learn more? Check out our other resources RESOURCES Follow us: www.tulsaheatersmidstream.com

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