The design of heat recovery system and economic analysis for an industrial plant boiler

It is assumed that approximately one-fourth of the energy consumption of many industrial plants throughout the world is lost by heat and gas thrown into the atmosphere. Recovering this huge loss is possible with recovery systems. In this study, studies on waste heat recovery have been done by conducting literature searches and a case study has been done. In the case study, a system for heat recovery of waste chimney gas from an industrial facility's natural gas boilers with annual average fuel consumption of 13.320.644 m³ was designed. This heat recovered from the waste flue gas is intended to be used for the preheating of the combustion air of the boilers. For the calculations made for the system, the actual operating data for the boilers of the industrial plant are used. Energy, heat transfer and economic analyzes have been carried out for the preheating system to be installed. After all analyzes and calculations, system's payback period is calculated as 7 months. The initial investment cost of the system is 62.670,80 TL and it is estimated that the fuel savings provided during the 15-year economic life period will be 1.121.410,23 TL with Net Present Value Method.