Study On Gasification Characteristics Of Distilled Spirit Lees In Dual Fluidized Bed Decoupling Combustion Process

Fermentation of distilled spirit in China is developed,and the distilled spirit lees is the largest by-product of the process.Distilled spirit lees which is rich in moisture and nitrogen has been considered as one of the important factors of environmental pollution.On the count of this situation the institute of process engineering,Chinese academy of sciences developed a circulating fluidized-bed decoupling combustion technology(CFBDC),which combines the advantages of the circulating fluidized bed and decoupling combustion technology.It can effectively dispose the spirit lees in large amount and less pollution.However,there are few studies on the influence of temperature,inherent moisture,simulated moisture and air equivalent ratio on the products of spirit lees' partial gasification.Therefore,this paper carried out a comprehensive study on the above gasification processes and the characteristics of the products.a comprehensive experiment about gasification of spirit lees was carried out in the pre-oxidation gasifier,and the products were analyzed by gas chromatography,GC-MS,FTIR infrared analyzer,simulated distillation and so on.Then using thermogravimetric analyzer and micro-fluidized bed analyzer to analyze the activity of char.Finally,I drew the following conclusions:Increasing the temperature(600??900?)during pyrolysis under nitrogen atmosphere would reduce the yield of tar and char,rising the yield of gas.Under the high temperature of 900? it could triple the yield of gas under the temperature of 600?.Meanwhile the concentration of combustible gas increased in pyrolysis gas.Heating could increase the activity of char and shortened it's burning time.At the same time,it will strengthen the cracking of tar and make the tar lighter.High temperature can intensify the action of vapor when there is vapor in the atmosphere.When spirit lees contained water the yield of tar and char would decline,and the yield of gas increased sharply.But at the low temperature(600?),the moisture would promote the yield of tar.Meanwhile the inherent moisture significantly improved the activity of char and it is positively correlated with the moisture.Simulated moisture's effect on reducing the yield of tar and char was more apparent,especially under high temperature(900?),but it's effect on improving the activity of char was not obvious.In addition,simulated moisture improved the content of CO and H2 in gasification gas,and the effect is stronger than that of inherent moisture.Vapor has reforming effect on tar,which increases the proportion of light components in tar.Adding the oxygen in the gasifier on the basis of inherent moisture could further reduce the yield of char and tar and improve the activity of char,but too much oxygen would reduce the activity of char.Oxygen was conducive to the cracking of phenols,aldehydes,naphthene and other molecules,which would lead to the increase of heavy components of tar.The gasification rate of char in CO2 atmosphere would increase with the increase of temperature.The higher the temperature,the faster it burned in the atmosphere of air.The water diffusion rate of hydrous char in a fluidized bed with inert atmosphere increased with the increase of temperature,and the effect of temperature increase is more obvious at high temperature.