Analysis And Optimization On Slagging For Incineration System With Rotary Kiln

According to the China Statistical Yearbook(2019),in 2017,the amount of hazardous waste produced in China reached 69.3689 million tons,the comprehensive utilization capacity was 40.4342 million tons,the disposal capacity was 25.5156 million tons,and the storage capacity was 8.7087 million tons.Effective utilization and disposal is the main way to deal with industrial hazardous waste.The rotary kiln incineration system has become one of the best disposal methods of hazardous waste because of its good material universality.However,due to the wide variety of hazardous wastes and complex morphology,the operating parameters of rotary kiln are mostly controlled based on the experience,so the slagging phenomenon of rotary kiln often appears during the operation process.The slagging of rotary kiln is the key to affect the normal operation of rotary kiln incineration system,which directly determines the operating rate of rotary kiln incineration system.Therefore,based on the rotary kiln incineration system of N Group Company and its hazardous waste,this paper makes a thorough study on the reason of slagging in the rotary kiln incineration system,optimizes the operating parameters of the rotary kiln incineration system of N Group Company by DOE test design method,provides support for the operation optimization of the existing rotary kiln incineration system,and provides reference for the design and transformation of the rotary kiln incineration system in the future.This paper firstly uses a variety of analysis methods,including scanning electron microscope technology(SEM),X-ray energy spectrum analysis(EDS),X-ray diffraction analysis(XRD),to study the residue characteristics of hazardous waste under high temperature incineration conditions.It is found out the causes of slagging in rotary kiln incineration system of N Group Company.Combined with the process characteristics of rotary kiln incineration system,the influencing factors of slagging in rotary kiln are determined,such as composition,calorific value,melting point of incinerator ash,temperature of rotary kiln,oxygen content of rotary kiln,rotational speed and pressure of rotary kiln.For the slagging problem of rotary kiln,four key factors affecting slagging of rotary kiln are selected by engineering analysis and practical experience,including the calorific value of incinerator,temperature of rotary kiln,oxygen content of rotary kiln and rotational speed of rotary kiln.Then the slag yield of rotary kiln is taken as the response variable,and the slagging problem of rotary kiln incineration system is optimized by DOE test design method.The mathematical model of the rotary kiln incineration system was studied by the Minitab software,and the optimal process parameters were obtained by response optimizer.Incinerator calorific value is 3700～4200 Kcal/kg,the rotary kiln temperature is 750℃,the rotary kiln oxygen content is 5%,and the rotary kiln speed is 0.6 rpm.The optimal process parameters are combined in the actual operation of the rotary kiln incinerator of N Group Company to carry out process debugging verification and optimization effect evaluation,then adjust and improve according to the operation conditions.Finally,the standardized parameter table of rotary kiln incineration system is worked out and improve the relevant operating procedures.It is used to guide the actual operation of rotary kiln incineration system,which significantly improves the slagging situation of rotary kiln incineration system.The slagging amount is obviously reduced.The clearing period of slagging is longer and the rotary kiln runs smoothly for longer.