Research On Pyrolysis Characteristics Of Food Waste And Rice Straw

In China,about 1.3 billion tons of kitchen waste are produced every year,resulting in a lot of waste of resources and environmental pollution.Kitchen waste contains a large amount of organic matter,which can be recycled and disposed of as a resource through effective utilization.Co-pyrolysis of kitchen waste and rice straw can improve the quality of pyrolysis oil and realize the resource,harmless and reduced disposal of kitchen waste and rice straw.In this paper,the mixed pyrolysis characteristics of kitchen waste and rice straw,the changes of functional groups of pyrolysis coke and the distribution characteristics of pyrolysis oil products were studied,which provided theoretical guidance for efficient heat treatment of kitchen waste.The main conclusions are as follows:(1)With the increase of rice straw blending ratio,the overall trend of TG curve gradually moved to high temperature stage,and the average activation energy showed an upward trend with the increase of rice straw blending ratio.By analyzing the sample yield,with the increase of pyrolysis temperature,the coke yield of kitchen waste and rice straw decreased and the gas yield increased The yield of kitchen waste pyrolysis oil reached the maximum at 600℃ and that of rice straw pyrolysis oil reached the maximum at 500℃.For mixed samples,the yield of pyrolysis oil is the highest when 30%rice straw is mixed at 500℃.(2)With the increase of pyrolysis temperature,the oxygen-containing functional groups such as-COOH,amide Ⅱ bond,C=O,C-O and so on in the pyrolysis coke of kitchen waste first increased and then decreased,and the absorption peak of C-H increased significantly.The addition of rice straw will weaken the functional groups such as O-H and C-H on the surface of pyrolysis coke,and the functional groups such as carbonyl C=O and ether bond C-O-C will increase first and then decrease.(3)With the increase of pyrolysis temperature,the aromatic compounds with 2～3 rings and above in the pyrolysis oil of kitchen waste are increasing.The addition of rice straw leads to the decrease of the fluorescence spectrum absorption peak intensity of 2～3 cyclic aromatic compounds,and the content of 2～3 cyclic aromatic compounds is between two single pyrolysis oils.The mixing of the two compounds can inhibit the production of 2～3 cyclic aromatic compounds in biological tar and inhibit the aromatization degree of pyrolysis oil.Nitrogen compounds in the pyrolysis oil of kitchen waste increase with the increase of pyrolysis temperature,but aliphatic hydrocarbons decrease first and increase.With the addition of the blending ratio of rice straw,the content of phenolic compounds in the mixture pyrolysis oil showed an increasing trend,and the content of hydrocarbon compounds reached the maximum(45.35%)when 30%of rice straw was added.The addition of a small amount of rice straw can increase the content of hydrocarbon compounds and the calorific value of pyrolysis liquid products.To sum up,when the proportion of rice straw is 30%,the pyrolysis liquid product has higher heat utilization quality and lower harmful substances.