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Hi,
I am working in optimizing the fuel gas for our fired heater, so can anyone help me in providing the fired heater efficiency calculation in Excel format. Your support will be much appreciated.
Also, any calculation available to help us to assess the heater performance will be very helpful.
Your prompt response will be highly appreciated!
 
Answers
27/05/2020 A: RUPAM MUKHERJEE, ENGINEERS INDIA LIMITED, rupammukherjee86@gmail.com
You can refer to API 560 standard which has very good info regarding calculation of efficiency of fired heaters. There is also ample literature available on the web.
27/05/2020 A: Morgan Rodwell, Fluor Canada Limited, morgan.rodwell@fluor.com
A simple explanation of furnace heater efficiency calculation can be found in API Std 560, or in Chapter 13 of ASTM Manual 58. You should be able to build your own Excel file using the equations found therein. Alternatively, if you have access to a process simulator (e.g. HYSYS, Aspen Plus, ChemCAD), you can build the air side of the furnace using a Gibbs reactor block to model the flame, and then cool the flue gas ion steps through the radiant and convection sections to 60°F (15°C) at either atmospheric pressure (HHV) or with a vapour fraciton of 1.0 (LHV). This allows you to model even air preheaters and flue gas recirculation accurately.
27/05/2020 A: Morgan Rodwell, Fluor Canada Limited, morgan.rodwell@fluor.com
A simple explanation of furnace heater efficiency calculation can be found in API Std 560, or in Chapter 13 of ASTM Manual 58. You should be able to build your own Excel file using the equations found there-in. Alternatively, if you have access to a process simulator (e.g. HYSYS, Aspen Plus, ChemCAD), you can build the air side of the furnace using a Gibbs reactor block to model the flame, and then cool the flue gas ion steps through the radiant and convection sections to 60°F (15°C) at either atmospheric pressure (HHV) or with a vapour fraciton of 1.0 (LHV). This allows you to model even air preheaters and flue gas recirculation accurately.
27/05/2020 A: Bruce Carr, Suncor Inc, matukaze1@hotmail.com
You can not operate an industrial heater using a spreadsheet. There are lots of calculations to tell you the theoretical amount of air that is required and targets. A heater can only be operated safely if the operators are trained properly on the correct flame pattern. Especially if there are multiple burners in a heater cell. Trying to operate efficiently using calculations instead of safely using visual observations has led to many heater explosions through out the industry. Don't even start this assignment unless the operators have been properly trained and are competent... not just qualified. A spreadsheet can not tell you if a burner is plugged, aligned properly, or if there is tramp air in the heater.