Experimental Studies On Utilization Of Oil Sludge By Thermal Treatment

With the repid development of economy,solid wastes production especially hazardous solid wastes is increasing quickly.According to the《Directory of National Hazardous Waste》, oil sludge fell into hazardous solid wastes.It's harmful to the environment,animals,vegetations and human's health.So,it's urgent to treat oil sludge harmlessly and economically.From analysing the components of oil sludge on different ways,thermal treatment are researched on different kinds of oil sludge,which gives some reference for oil sludge treatment.Firstly,methods fit for analyzing oil sludge components was explored.The conclusions are: using hybrid solution with methano:(60℃-90℃)petroleum ether:Trichloromethane equals to 1:1:1 as ingredients to disslove oil sludge sample,then using the pre-dissolved solution doing Karl-Fischer water determination.The data seems to be accruate;Ash and volatile analysis method in the proximate analysis of coal can get the data of the rate of slag of oil sludge;the way of subtraction can be used to draw the oil-bearing rate on the basic of the correct data of water-bearing rate and the rate of slag.Sencondly,transportation,physical and chemical characteristics of oil sludge from certain oil field was analyzed and incinerated on the pilot scale fluidized bed.The results shows that oil sludge can combust steadily without auxiliary fuel.The gas pollutants emission of oil sludge incineration in the fluidized bed can satisfy the requirement of the standard of national hazardous waste pollution control while deacidification system is set up.The heavy metal-Cd content in fly ash is higher than the third degree limitation in《Environmental quality standard for soils》,stabilization and land filling of fly ash as hazardous waste is suggested.According to the results,oil sludge fluidized bed incineration is a feasible method.Thirdly,thermogravimetric experiment is done toward a certain kind of oil sludge,and was pyrolysised in a pilot-scale rotary kiln with muti-condition.The result shows that:the yield of pyrolysis oil reaches to highest level when the temperature is 500℃,the turning speed is 0.8r/min;according to the pyrolysis product,the oil part can produce a series of petroleum products,and the pyrolysis gas and residue can be used as energy to heat rotary kiln.Finally,the oil sludge is pyrolysised in a tubular resistance furnace.The impact of temperature and residence time is investigated.Result shows that:Neither 420℃nor 720℃is considered to be a proper temperature in oil sludge pyrolysis.Compared to 520℃,620℃has larger secondary cracking reaction level,produces more cracking gas,recovers less pyrolysis oil. The trend of medium oil turns to light and heavy oil fraction increases as temperature goes higher,which result to restore more light and heavy oil yield at 620℃than 520℃.Both quality and quantity of pyrolysis oil can be promoted when using multi-part pyrolysis,and the degree goes larger as the pyrolysis parts increases.In conclusion,300℃-410℃-520℃(0.1m) is considered to be the best experimental condition.