Reaction Characteristics Of Kitchen Solid Waste By Chemical Looping Gasification

With increasing population and the continuous rapid development of catering services,the amount of kitchen solid waste will increase year by year.At present,various countries are vigorously developing kitchen solid waste disposal technology.This technology should conform to the three principles of harmless,reduction and recycling.Chemical looping gasification（CLG）is a clean and efficient disposal technology that transfers the lattice oxygen to fuel by the oxygen carriers（OC）,and without any direct contact with the air,the fuel can accomplish the gasification reaction.The kitchen solid waste quality ratio of municipal solid waste（MSW）approaches 50%.Effectively dealing with kitchen solid waste disposal can greatly reduce the amount of MSW.Copper slag is an industrial copper slag,using copper slag to prepare copper slag oxygen carrier to achieve the recycling of copper slag.The main findings of this thesis are summarized as follows:（1）Iron and copper compound oxygen carrier（CuFe₂O₄/ATP）were prepared by sol-gel method.Iron oxide（Fe₂O₃）and copper oxide（CuO）are active components.The attapulgite（ATP）is inert carrier.Investigation into the chemical looping gasification of starchy kitchen waste for preparing syngas was carried out in a batch fluidized bed reactor.Typical starchy kitchen solid waste,including rice and wheaten food,was used as raw materials.The effects of operating temperature,steam flow rate and O/C mole ratio on the gasification process were studied.The results demonstrated that the optimal operating conditions of chemical looping gasification of starchy kitchen waste was 850℃,1.0 g·min^-1 of steam flow rate and 0.5 of O/C molar ratio.Under these conditions,the yield of syngas was up to 0.822 m³·kg^-1.The average concentration of H₂ and CO was 45.74%and 22.24%,respectively.The carbon conversion rate reached 83.57%.After ten redox reaction cycles,the crystal structure of the oxygen carrier principally are CuFe₂O₄.A portion of the oxygen carrier sintered slightly,but it still had excellent cycle characteristics.（2）The copper slag oxygen carrier was prepared by copper slag.Typical protein and fat food kitchen solid waste,including meat and soybean food,was selected as raw materials.The effects of operating temperature,steam flow rate and O/C mole ratio on the gasification process were studied.The results demonstrated that the optimal operating conditions of chemical looping gasification of protein and fat food kitchen solid waste was 900℃,0.7 g·min^-1 of steam flow rate and 1.0 of O/C molar ratio.Under these conditions,the yield of syngas was up to 0.968 m³·kg^-1.The average concentration of H₂ was 49.39%.The carbon conversion rate reached 86.23%.After cyclic reaction experiments,the concentration of each gas product is stable.The copper slag carrier has stable crystal structure,and the surface morphology is not found to be sintered.（3）Two kinds of components of kitchen solid waste,i.e.starchy kitchen solid waste,protein and fat food kitchen solid waste,were mixed physically.The mixed component of kitchen solid waste was made.The CuFe₂O₄/ATP oxygen carrier and copper slag oxygen carrier were used for chemical looping gasification,with the experimental data being analyzed.