Study On Co-pyrolysis Process Of Oily Sludge And Waste Tires

Oily sludge is an indispensable hazardous solid waste produced by oilfield development.its output is large,and the annual production of different types of oily sludge in China is as high as several million tons.On the one hand,the oily sludge has special properties such as high ash content,high cohesiveness and complex composition.so it is difficult to handle.Leaded to it become a major obstacle to the development of the oil industry.On the other hand,oily sludge has high recovery and utilization value,because of it contains large oil content,high petroleum compounds.Therefore,at the same time as realizing the reduction and harmless treatment of oily sludge,how to effectively increase the recycling and utilization rate of petroleum resources has become the focus of research staff at home and abroad.This paper presents the technical route of co-pyrolysis of oily sludge and waste tires.The co-pyrolysis of oily sludge mixed with waste tires with high heat and high organic content can promote the pyrolysis performance of oily sludge,increase the yield of pyrolysis oil and improve the quality of pyrolysis oil.Therefore,the research of this paper will provide strong data support for the resource treatment technology of oily sludge.The main research work in this article includes the following aspects:(1)the characteristics of separate pyrolysis and mixed pyrolysis of oily sludge and waste tires were investigated using thermogravimetric analysis-Fourier transform infrared spectrometer(TG-FTIR),it is found that pyrolysis of waste tires is easier than that of oily sludge.By analyzing the effect of different heating rates on pyrolysis,it was found that pyrolysis at a lower heating rate has sufficient pyrolysis,good pyrolysis reduction effect,and low pyrolysis activation energy.The co-pyrolysis results showed that the main stage of the pyrolysis reaction of waste tires coincided with the second stage of the pyrolysis of oily sludge.Through the synergetic effect analysis,it was found that the synergistic effect of mixed pyrolysis of oily sludge and waste tires was obvious.Co-pyrolysis can promote the precipitation of volatiles in the pyrolysis reaction.By analyzing the characteristic parameters of pyrolysis,it was found that the mixed pyrolysis could make up for the lack of the high initial analysis temperature and final pyrolysis temperature for the separate pyrolysis of oily sludge and waste tires.The results of pyrolysis kinetic analysis show that the first-order reaction model can describe the process of separate pyrolysis and co-pyrolysis of oily sludge and waste tire,and the co-pyrolysis shows a promotion effect on the kinetics.(2)The study of the co-pyrolysis oily sludge and waste tires of based on tubular furnace found that the synergistic effect of co-pyrolysis is mainly reflected in the interaction between pyrolysis oil and gas.The co-pyrolysis promotes the pyrolysis reaction,so that the volatilization is fully precipitated,the yield of pyrolysis oil is increased,and the yield of pyrolysis oil shows the trend of "decrease first and then increase" with the increase of the final pyrolysis temperature.When final pyrolysis temperature is 550? and the mixing ratio is 70%OS+30%WT,the mutual promotion is most obvious,the yield of the pyrolysis oil is the biggest,the output of the char is reduced,and the actual yield of the pyrolysis oil increases by 13.6% compared with the theoretical value.Analysis of pyrolysis oil products found that copyrolysis can increase the H/C value,raise the calorific value and enhance the stability of pyrolysis oil which the actual yield value increases by 7.12% compared with the theoretical value.(3)The study of the co-pyrolysis of oily sludge and waste tires based on the pyrolysis furnace of the self-made rotary kiln,it was found that the pyrolysis effect is obvious compared with the pyrolysis of tubular furnace,the solid yield of the pyrolysis of the self-made rotary kiln is decreased and the yield of oil and gas is increased.The pyrolysis oil product is structurally stable and has better performance than the pyrolysis of the tube furnace.It can be used as a fuel and or further processed to utilize its high value product.Through economic analysis,it was found that when the rotary kiln pyrolysis furnace was calculated at a pyrolysis efficiency of 85%,the processing income per ton of material can be recovered as 744.18 yuan.Obviously,the economic benefit was significant.Therefore,this technology can be further fully exploited for the efficient resource treatment of oily sludge.