A New Way Of Coke Oven Gas Energy Application And Energy Efficiency Research

In China,coking industry produces a large number of coke oven gas(COG)every year.At present,COG has some issues,such as overcapacity and the environmental pollution.Defusing excess capacity and energy conservation and emissions reduction are the most serious and urgent time topic in China,which is related to the sustainable development of our country's major problems.This paper proposes a novel type of hydrogen production and power generation system based on COG,giving a new way of using traditional energy.And analyses the thermodynamic performance of the new system by the energy analysis and exergy analysis,to explore process energy conversion mechanism of the system key,so as to achieve efficient utilization of COG and the purpose of energy saving and emission reduction.Firstly,a novel type of hydrogen production and power generation system based on COG was proposed.COG is sent directly into the pressure swing absorption(PSA)device,to realize the separation of hydrogen and carbon gases.Carbon gases react with oxygen carrier to carbon dioxide and water in chemical-looping combustion(CLC)reduction reactor.The preheated and pressurized air goes into the CLC oxidation reactor,to provide the combustion of oxygen,at the same time,absorbs the heat of the without flame combustion,after entering the combustion chamber.In the combustion chamber,a part of the separated hydrogen reacts with the rest of the oxygen of the air to give off heat to improve the state parameters of working fluids.The working fluids of high temperature and high pressure generate power in the gas turbine.Then,the high temperature exhaust of gas turbine generates power in waste heat boiler,which makes full use of the waste heat,increasing the system energy efficiency.Secondly,the energy analysis and exergy analysis was carried out on the new system,and establish a mathematical model of thermal analysis to calculate the energy loss and exergy loss of the system and each equipment unit.Find that the system energy loss is mainly concentrated in the heat exchanger and waste heat boiler equipment units,however,exergy loss is focused on the combustion gas turbine combustor and CLC reactor energy conversion equipment units,energy loss and exergy loss of system link not coincide,exergy analysis theory can more clearly point out that weak links of systen.Finally,compared with the traditional COG steam thermal power generation system,discover the new thermodynamic performance of the system is superior to the traditional system,the exergy efficiency improves by 19.27%,the new system compared with traditional system has no obvious weaknesses,and achieves improving the traditional energy utilization,energy conservation and environmental protection.