Analysis of Gas Fired Furnace and Improve its Efficiency using Waste Heat Recovery Unit

Abstract

Natural gas fired bogie hearth batch heat treatment furnace is used for changing the properties of various materials like annealing, hardening, tempering, normalizing and also used for stress relieving process to increase the metal ductility. This report contains the thermal analysis and designing of natural gas fired furnace with the algorithm and nd the thermal parameters like ow rate of natural gas, air-fuel ratio, excess air, ultimate and proximate analysis of natural gas, exhaust temperature, flow rate of exhaust gas, burner flame temperature, gas red burner fuel ow, air pipe design and gas line components of L&T,MHPS,Turbine Generator,Hazira. The Waste Heat Recovery Unit is also designed for preheat the combustion air upto 250 º C with use of exhaust gas to decrease the fuel supply and increase the furnace e ciency.The recuperative (cross ow compact plain tube bundle type heat exchanger) is also simmulated which will save more fuel after installing recuperator. The thermal e ciency of furnace will increase around 8 to 10%. Compact plain tube heat-exchanger is also modeled using Creo-3.0 and also carried out in Ansys.17 (CFD) and HTRI-Heat Transfer Research Incorporation to get better result. The n-tube heat exchanger and plain tube heat exchanger are also compared with considering manufacturing cost. The graphical representation of various pipe size, tube pitch, length of tube etc. are described with proper analysis of ASME and TEMA standards. The Kaizen and 5-S analysis will be generated for waste heat recovery unit. The report gives the design methodology and installation of WHRU. It also describes the cost estimation and cost analysis of material.