Experimental Study On Medical Solid Waste Pyrolysis And Fractional Condensation Of Pyrolytic Oil

With the number of hospitalizing person times increased in our country,more and more medical wastes have been generated in recent years.Which brought a lot of troubles and potential harm to social safety and people's physical health.Reasonable waste disposal and maximal recycling of the organic components have great significance to promote the development of recourse-saving and environment-friendly society.Compared with traditional incineration,pyrolysis is a more efficient and cleaner treatment.It can reduce the emission of pollutants and generate recyclable gas,liquid and solid products,which can fully recycle the waste resources and energy.However,the current research on the pyrolysis of mixed medical solid waste and resourceful disposal methods and utilization ways of the products are rarely systematically reported.This subject directly use the sterilized mixed medical waste as the pyrolysis raw material,focuses on the distribution and the composition properties of the pyrolysis products.And then,we further separate the pyrolytic oil.The component and utilization value of products were systematically analyzed finally.Firstly,the medical solid waste were pyrolyzed under 450?to 550?.Sample analysis of the pyrolysis products showed that the ash content of solid products accounted for 60.12%,and the calorific value was 3201.26 kcal/kg.They were greatly improved after subsequent water washing and pickling treatment.The combustible components of gas products accounted for 83.22%,the calorific value was10995.02kcal/Nm³,and the main ingredients was H₂,CO and other flammable gases.The composition of the liquid products were very complicated,and the calorific value was 8972.82 kcal/kg.For solid and gas products with relatively simple composition,they can be directly used as alternative fuel.However,for liquid products with complex component and high viscosity,it was difficult to directly apply them in practical life.Therefore,this paper focused on the separation and purification of liquid products.Secondly,the liquid products were separated by atmospheric distillation and vacuum distillation.During the atmospheric distillation process,it was found that the vaporization component accounts for about 40%,and the boiling point ranges was80¹30?.In the vacuum distillation experiment,obvious enrichment phenomenon was found,the boiling point range of the vaporization component was mainly concentrated in the temperature range of 60⁶4?and 84⁹0?under the vacuum of 0.04 MPa.Its composition and calorific value were measured,and further resource utilization directions were proposed.Based on the distillation experiment,the fractional condensation process of pyrolysis oil was further explored.The effects of vacuum degree,condensing temperature and heating intensity on the condensation process were analyzed.The optimum vacuum was 0.04 MPa,and the best heating temperature under this vacuum was 140?.Finally,the composition of the escaping components in the condensation process was determined.It was found that its main components were small molecule gases such as silicomethane and propylene.The viscosity of the residual components was determined,in order to offer data support for the solution of tar clogging problems between equipments and pipelines in practical applications.This study through the research on the pyrolysis of mixed medical solid waste and the composition of pyrolysis products,the following resourceful treatment methods and utilization ways are systematically analyzed,which has practical significance for the industrial application of medical solid waste pyrolysis.