Study On The Pyrolysis Characteristics And Product Potential Distribution Of Organic Components In Sludge

Municipal Sewage Treatment sludge is a kind of solid waste,which is composed of organic matter and inorganic components,the organic components play an important role in the process of sludge utilization.In order to realize the harmless and resourceful treatment of sludge and enhance the availability of organic components in sludge,the effects of different organic components on the distribution and potential calorific value of the pyrolysis products of sludge were studied in combination with the pyrolysis technology of sludge,it is of great significance to reveal the evolution and caloric value recovery of organic components under different pyrolysis conditions.On the basis of defining the composition and properties of sludge,the change of sludge composition before and after pyrolysis was studied.The organic matter content of sludge was 50.7%,it is mainly composed of protein,carbohydrate and lipid,which account for 20.5%,7.3% and4.1% of the sludge components respectively,complete lysis is basically achieved.The effects of pyrolysis temperature,pyrolysis time and pyrolysis rate on organic components,protein,polysaccharides and lipids were investigatedThe correlation between the three-phase products and the organic components was studied.The results showed that with the increase of pyrolysis time and temperature,the solid product yield decreased while the gas product increased,the yield of liquid phase product is better at10 ℃/min heating rate.The rapid consumption of polysaccharides during the initial stage of solid-phase pyrolysis is the main reason for the decrease of calorific value of solid-phase products,the increase of gas-phase products yield and fixed carbon content,the yield and properties of the liquid phase products are mainly affected by lipid lysis and protein transformation,but not by the pyrolysis process at high temperature,the highest conversion rate of each component was10 ℃/min.In order to understand the effect of organic components on the potential distribution of pyrolysis products,the correlation analysis between the conversion coefficient of organic components and the calorific value of the products and DAEM kinetic analysis were used.The results showed that there was a strong correlation between protein,lipid and polysaccharide and the calorific value of solid-phase products.For the calorific value of solid-phase products,the correlation is lipid >polysaccharide > protein,and the corresponding calorific value changes are 6500 cal/g,5000 cal/g and 2000 cal/g,respectively,the order of influence of three organic components was lipid> protein>polysaccharide,and the corresponding caloric values were 2000 cal/g,1500 cal/g and 1000 cal/g,respectively,the inert organic components also have some influence on the total calorific value of the products after pyrolysis.The total calorific value of the products can change by 1000cal/g with the change of the content of the components,but it is mainly for the gas and liquid phase products,the connection with the solid product is weak.This study provides a new way to analyze the relationship between the pyrolysis of organic components and the potential calorific value recovery of the products,and provides some data support for the optimization of the sludge pyrolysis process.