Hydrogen Production By Gasification Of Biomass And Coal In Supercritical Water

Currently,it has become the key to solving our energy problems that how to rationally use fossil fuels and develop new energy sources at the same time. Hydrogen is clean and efficient as the secondary energy.The method that converting biomass or the mixture of biomass and coal into a hydrogen-rich gas by the unique gasification performance of supercritical water(SCW)can improve the utilization of coal and biomass.Further more,the process is efficient and clean which fits well with the “Saving,clean and safe”strategic approach that has been stated in “Energy Development Strategic Action Plan”.In this paper,the simulation of hydrogen production from gasification in SCW was maded by Aspen plus by using four model compounds of biomass:ethanol、glycerol、glucose and cellulose.Then a comparison was maded between the results and the data of experiments which indicates the influence of temperature,pressure,feed concentration and other operating parameters on the parameters of gasification effects:hydrogen yield、gasification efficiency、carbon efficiency and hydrogen efficiency. And it showed gasification laws and main factors of the four model compounds of biomass in the process of hydrogen production of gasification in SCW. The second one was to make a simulation in Aspen plus for hydrogen production by co-gasification of coking wastewater/ lig-nite in SCW. Then,the effects of temperature and coal water slurry(CWS) in hydrogen production were studied and the main factors affecting the effect of co-gasification were propered. At last I conducted a preliminary study on the synergies of hydrogen yield in hydrogen production by co-gasification of coking wastewater and lignite including several reasons.This paper has showed that the main production is H2、CO2、CH4 and CO by the hydrogen production of these four model compounds of biomass, coking wastewater and lignite SCW. Temperature is an important factor in hydrogen production,and hydrogen yield can be raised as the temperature increases. Feed concentration has a certain effect in hydrogen production while the effect of pressure is small. The emergence of synergies can be seen in the process of co-gasification by coking wastewater and lignite in SCW which is consistent with experimental results. This performance could be the result of some reasons such as a high level of hydrogen-carbon ratio in the process of co-gasification, characteristics of gasification in SCW, the increase of temperature influenced by lignite and the volatiles removal in the reaction.