Comparison of waste heat recovery exchangers of furnace combusted with different fuels

Abstract

This study investigates and compares the low-temperature waste heat recovery exchangers of glass melting furnaces using liquid natural gas (LNG), methanol and dimethyl ether (DME) as fuels. A glass melting furnace with a production of 1 t/year was used to combust the fuel with air, and the waste heat exchanger served to recover the heat from the flue gas at a low temperature to preheat the air. The net present value (NPV) and carbon dioxide (CO2) emissions acted as the evaluating parameters of the heat exchanger. The results showed that the methanol combustion programme yielded the maximum NPV and carbon dioxide emissions. The LNG combustion programme yielded the lowest values and the parameters in the DME combustion programme are always in the middle. Considering the income of the heat exchanger and carbon dioxide emissions, the glass melting furnace with DME as the fuel is the optimal programme.