Study On Hydrothermal Liquefaction Treatment And Resource Utilization Of Typical Industrial Sludge

Different industrial sludge has its special pollution properties,and it is easy to cause more serious secondary pollution problems in the process of industrial sludge treatment.Compared with traditional sludge treatment,hydrothermal liquefaction is an ideal method to treat organic solid wastes with high water content.Therefore,hydrothermal liquefaction treatment of different industrial sludges,studying the characteristics of different products and the characteristics of bio-oils are of great significance for the search for a common system solution for industrial sludge recycling.In this paper,batch-type high-pressure reactor was used to treat the typical industrial sludge penicillin sludge(PS)and paper sludge with hydrothermal liquefaction(HTL).The research work and results are as follows:(1)Understand the physical and chemical characteristics of the two sludges through industrial analysis,elemental analysis and pyrolysis characteristics,and analyze their characteristic pollutants:.The study found that the two kinds of sludge experience the three stages of typical pyrolysis period in hydrothermal liquefaction process.The difference is that the main pyrolysis stage of PS is between 300? and 360?,and the papermaking sludge is around 400?,which is related to the nature of the sludge itself..The element N in penicillin sludge is its characteristic pollutant;the fixed carbon content of paper sludge is about 4 times that of penicillin sludge.(2)X-ray photoelectron spectroscopy(XPS)was used to study the effect of hydrothermal liquefaction on products at different temperatures and the redistribution and existence of nitrogen in penicillin sludge liquefaction.The maximum oil production of both types of sludge appeared at 340 ?,but the oil production of papermaking sludge was generally higher than that of penicillin sludge.During the hydrothermal liquefaction of penicillin sludge,less than 20% of the N element is retained in the solid residue,and the remaining nitrogen is converted into other phases.The amino nitrogen in PS is mostly present in the water phase in the form of Org-N.The remaining amino nitrogen was converted into pyrrole-N?pyridine-N and quaternary-nitrogen in the solid residue.N in the oil phase existed in the form of heterocyclic N.The specific conversion path of N element was analyzed.(3)Comparative analysis of characteristics of hydrothermal liquefied bio-oil and water phase products of two kinds of sludge.The biomass oil obtained from penicillin sludge is more complex and not easy to use.The calorific value of biomass oil obtained from paper sludge is relatively low,but it is better in the simple composition and relatively more concentrated products.A large number of organic components were detected in the aqueous phase products of both sludges,and chloride ions were detected in the aqueous phase products of papermaking sludges.