| Waste tire crack is an efficient technology for solid waste resource recycling.However,the current waste tire cracking products have problems of high sulfur content and heavy components of cracked oil,which make it difficult to utilize the products with high value,and the oil and gas pipelines are easily blocked.In order to solve the above problems,in this paper,the catalytic cracking characteristics of waste tires are studied,based on microwave heating waste tires.On the basis of exploring the effects of catalyst type and catalytic temperature on the heavy composition of the cracking oil,the effect of microwave heating on the migration law of the sulfur element in the product is studied.Further,microwave heating is coupled with catalytic cracking techniques,and the heavier component content in the sulfur content and lysis oil in the waste tire cleaner is reduced from the source.In view of the high content of heavy components in cracked oil,an ex-situ catalytic technology for source control of waste tire cracking products is developed,the influence of catalyst type and catalytic temperature on the properties of cracked products is studied.The results show that ex-situ catalysis has a conversion effect on heavy components,and the catalytic effect of dolomite is ideal.With the increase of temperature,the content of heavy oil shows a downward trend,and the content of light oil increases first and then decreases.When the temperature reach 400 ℃,the light oil content increases by 23.21%,and the heavy oil decreases by 52.74%,which is the optimal catalytic temperature for the efficient conversion of heavy components while retaining high-value light components.Aiming at the problem of high sulfur content in solid-liquid phase products,a microwave coupled heating technology for efficient pyrolysis heat source control of waste tires is designed.In this paper,the effects of microwave power density,pyrolysis temperature and heating rate on the migration of sulfur in pyrolysis products were studied.The results show that low microwave power density is favorable for sulfur migration from solid-liquid products to gas products.When the microwave power density is 2 W/g,sulfur content in solid-liquid products decreases by 28.29 % and 27.89 %,respectively,and sulfur content in gas products increases by 97.92 %.With the increase of pyrolysis temperature,the sulfur element in the liquid phase is transferred to the gas phase significantly,but the sulfur content in the solid phase is not affected.When the pyrolysis temperature is 550 ℃,the sulfur content of liquid product decreases by 35.03 % and that of gas product increases by 29.98 %.The rate of warming rate is small in the migration of sulfur elements in the lysis product.The optimum cleavage condition is: the microwave power density 2 W/g,the cleavage temperature is 550 °C,the temperature rise rate is 10 °C/min.Based on the above studies,microwave heating is coupled to catalytic cracking techniques,and the effects of different catalysts and catalytic temperature on the quality of lysis are studied under better microwave heating conditions.The results show that the HZSM-5 catalyst is significant to reduce the content of heavy oil,and when the catalytic temperature reaches 500 °C,the heavy oil content is reduced by 78.64 %.Dolomite catalysts can effectively increase the content of light oil,when the catalytic temperature reaches 400 °C,the light oil content increases by 29.71 %. |
