Energy Analysis Of Polygeneration Systems Of The Stage-feed Oxygen Entrained-flow Gasifier With Water-cooled Wall

With energy resources of our world are increasingly lack and needy, coal polygeneration technology has become a new topic in the field of energy. Polygeneration system has the characteristics of the efficient use of energy, effectively reduce emissions of pollutants and greenhouse gases, become contemporary clean coal technology, therefore the polygeneration became one of the clean coal technology in the contemporary as a priority development direction of the energy sector in the national "12th Five-Year Plan" and the long-term development planning.In this thesis, the coal polygeneration technology is based on Shanxi Yangmei Fengxi Fertilizer Industry (Group), this system utilizes the Aspen Plus software to simulate the system process. The Stage-Feed Oxygen Entrained-flow Gasifier is a new type gasifier of independent intellectual property rights in FengXi Group, it runs well since it is in commercial service. In order to optimize the system, it is necessary to analyze the energy loss of the polygeneration systems and obtain all the technical parameters, but to make sure the correctness of the simulation, first of all, a large amount of actual running data must be collected to adjust the Aspen Plus software. On this basis, Analysis the influence of reactor temperature, reactor pressure and recycle ratio on methanol yields, its determine the best economic conditions:the reactor temperature was530K; the reactor pressure conditions maintained at5.2-5.4MPa; the system running in recycle ratio of3.8was the most economical.Energy method and exergy method are used to analyze the whole process, the energy flow chart and exergy flow chart are produced for this polygeneration systems. The results show that Calculated methanol conversion efficiency from energy method was53.78%; the heating rate was23.44%; the sum of the heat loss was22.78%, and the gasification quenching process possess the maximum energy loss. Calculated methanol conversion efficiency from exergy method was53.98%; the exergy heating rate was2.96%; the sum exergy loss of combustion was16.73%; the syngas separation and throttle process possess the maximum exergy loss that was11.98%. the energy loss and exergy loss of the purge gas release process are more than the average loss. It is also concluded that the burning exergy loss can be reduced in high pressure.According to the two kinds of calculate result show that the purge gas in methanol synthesis process has large quantities and High quality of energy,so that need to increase the gas turbine system to achieve energy recovery. The gasification quenching process possess the maximum energy loss, but the exergy calculation results show that its power capability is low.