Experimental Study On Copyrolysis Of Waste Tires And Engine Oils

The tire thermal cracking technology is one of the effective methods to convert junked tires into renewable energy sources.It disposes junked tires in a reasonable,recycling,harmless way.Due to the poor thermal conductivity of the rubber powder,problems including low caloric transmission efficiency,uneven temperature distribution,serious regional coking,and so on,arise in the pyrolysis of the rubber powder,which seriously affects the pyrolysis reaction efficiency.At the same time,uneven heating of the rubber powder seriously restricts the productivity of pyrolysis gas and pyrolysis oil,which have higher utility value among pyrolysis products,leading to the low added value of pyrolysis oil and low pyrolysis conversion efficiency.To solve that problem,this paper proposes engine oil as the heat conduction agent to evenly heat the powder,to lower the required pyrolysis temperature and to reduce carbon deposition and coking.This method will improve the yield of tire pyrolysis and increase the pyrolysis efficiency of rubber powder.In addition,the co-pyrolysis process of oil and rubber powder has obvious coupling effect,which is beneficial to the optimization of the products.Therefore,the experimental study on the co-pyrolysis of oil and rubber powder provides the theoretical basis and technical support for improving the utilization rate of tire pyrolysis technology and realizing the reasonable,recycling utilization of waste oil and tire.(1)Through the study of the basic properties of tire rubber powder and engine oil,the physical and chemical properties of the two were clarified and the theoretical basis of the oil used as the thermal decomposition agent of the powder was proposed.(2)The thermogravimetric analyzer was used to analyze the different pyrolysis stages and the corresponding temperature section of change rule during the separate heating as well as co-heating process of the rubber powder and oil.The effects of various heating rate,particle size and oil blending ratio on pyrolysis process and surplus carbon black were compared.(3)Pyrolysis experiments under different factors were carried out on the homemade small-scale fixed-bed pyrolysis experiment device to investigate the productivity and change rule of three-phase products under various oil mixing conditions.The experimental results showed that when the powder particles were small,the particle size had little effect on the pyrolysis reaction.The pyrolysis process was mainly affected by the temperature as well as the blending ratio of the rubber powder and engine oil.When the pyrolysis temperature was 450 ? and the oil blending ratio was 40%,the thermal conductivity of the oil on the powder was the best,and the amount of the reactive powder was the largest.(4)The primary reaction kinetics models were adopted to carry out pyrolytic kinetic analysis of the co-pyrolysis of the powder and oil.Reaction kinetic parameters were determined.The activation energy of the co-pyrolysis of the powder and oil was about 66 KJ / mol.(5)The composition and properties of the pyrolysis oil and pyrolysis gas as well as the yield distribution at different engine oil blending ratios were analyzed,which provided the theoretical basis for optimizing the pyrolysis conditions and obtaining the target products for different use.(6)The properties and composition of pyrolytic carbon surface were analyzed,and the effects of different oil blending ratios on the product properties of pyrolytic carbon were compared.The adsorption of SiO2 and Al2O3 on the S element in pyrolytic carbon was analyzed by scanning electron microscopy and energy dispersive spectroscopy.