Gasification Process Experimental Study On Biomass In The Fluidized-bed

With the development of economy,the energy demand will be continuous increase.At present,kinds of new energy are developed by countries to sustaining use,and transformation and utilization of biomass is very important in all of new energy and renewable energy.Because the volatile components of biomass is high,the activity of carbon in biomass is high,the content of sulfur and ash in biomass is low,it is an ideal raw for gasification.The method of traditional fixed-bed gasification is inefficient,production intensity is smaller,so it is not suitable for large scale industrialization.Fluidized bed gasifier,in particular, above disadvantages can be overcome by circulating fluidized bed(CFB).Because gasification intensity of CFB,fuel quantity into the CFB and air volume can be controlled strictly,it is very suitable for large-scale industrial gas supply systems, and the calorific value of gas can be discretionary adjusted in a certain range. Therefore,technology experimental study on biomass gasification using CFB is presented.Gasification process experiment of biomass is studied in CFB.The rice husk powder,rice husk,corn stalk powder were used for gasification experiments and river sand was used as bed material in CFB,and the air was used as gasifying agent.The results show that the rice husk powder for gasification reaction is good in this device,and scale up rule of CFB can be predicted from experiment results.Air is gasifying agent for biomass gasification in CFB,so calorific value of gas is lower.If the water vapor or oxygen is used as gasifying agent for biomass gasification,the cost will be higher.Therefore,double fluidized bed for gasification process is present in this paper.A combustor and a gasifier are connected in parallel and air is added into the gasifier as gasifying agent.Based on the concept of the double fluidized bed,a cold model with a combustor of 100 mm in diameter and 5000 mm in height,a gasifier of 211 mm in diameter and 1900 mm in height is built.The results show that the test requirements can be meet by the key components of system;system pressure difference can be impacted of circulation volume of system,so it must be monitored in test.According to test results by computing,if the temperature is different between combustor and gasifier,the heat is carried by circulating ash is increased linearly with circulation quantity and residence time for biomass in gasifier is 25 s,so a good gasification reaction can be ensured.Based on the cold test,a hot test rig,which has the same size as the cold model,was built.Gasification tests on Longkou lignite first,and the results show that the gasification process route is feasibility.