Study On Pyrolysis Of Waste Plastics Into Liqud Fuel Oil

Waste plastic originated widely is much hazardous and difficult to dispose. As a solution for waste plastic pollution, production of liquid fuel oil by pyrolysis of waste plastics has been paid much attention. Because of old and simple technology, the problem of un-continue feed, un-continue clear the residue at the bottom of reactor, apt to coke in the pipe and the secondary pollution are existed in the production process. So the pyrolysis of waste plastic, the characteristics of catalytic reforming and reforming catalyst were studied in this thesis, the technologies of manufacture fuel oil from waste plastics, the mixture of waste plastics and used oil, and the mixture of waste plastics, used oil and heavy oil were studied, too.Experiment demonstrated that every kind of waste plastic has its own special characteristic of thermal pyrolysis versus temperature. Research on the characteristic is helpful to study the effect of other factors on the thermal pyrolysis of the waste plastic. The yields of liquid, carbon residue and gas, and the quantity of gasoline, diesel and heavy oil generated by pyrolysis of different kinds of waste plastic at different temperature were studied.Effects of variety of condition on the process of catalytic reforming were studied in the thesis, the performance of kinds of catalyst were compared to each other, too. Experiment showed that the product components of catalytic reforming are distinctively different from that of thermal pyrolysis.Taken Al (NO3)3, Zr(NO3)4, and (NH2)2 CO as material, the reforming catalyst with Al2O3 as carrier and ZrO2 as main component was prepared. Research demonstrated that, in the course of catalytic reforming of the product from the pyrolysis of waste plastics, with this catalyst used, the yield of oil is high, the quality of gasoline is improved obviously, and what's more, the coking rate is low.In the course of thermal pyrolysis of waste plastics, addition of heavy oil can obviously improve the heat transfer and mass transfer and decrease the residue production. So this technology can make better use of heavy oil, decrease the coking, and improve the quality of gasoline with the great increase of RON. On the basis of this research, the technique of production fuel oil from the mixture of waste plastic,waste oil and heavy oil was studied, and the pyrolysis process with fixed bed as reactor was designed.Fluidized bed technology with equipment of continuous feed and residue removal was studied. On the basis of this research, the whole process for the technology was designed, and demonstration production facility was established, which dispose of the mixed waste plastics at the rate of 1 t/h. Through the facility, the continuous production of fuel oil by pyrolysis of waste plastic was achieved, the gasoline and diesel met national standard were produced, and the problem of the secondary pollution met in the product was properly solved.