Abstract: Oily sludge refers to the sludge mixed with crude oil, various refined oil residue and other heavy oil, which is widely produced in the process of crude oil exploitation and transportation with output of 5 million tons every year in China. The harmless and recycling utilization of oily sludge has become a significant issue in oil field development. Pyrolysis is a promising technology to treat oily sludge. However, the conventional pyrolysis technology has the problems of high energy consumption, low efficiency and low quality of pyrolysis products, which restrict its further utilization. Co-pyrolysis of biomass and oily sludge for high quality products was proposed to realize the polygeneration utilization of biomass and oily sludge by the complementary of material properties. The mechanism of the co-pyrolysis was investigated based on the effects of biomass components and blending ratio. The quality of oil, char and gas products were significantly improved. The oil has the potential to be used as fuel because of the higher contents of gasoline, kerosene and diesel components. The gas can be used as fuel gas, and the char with better pore structure can be further developed as catalysts or electrode materials. Polygeneration application of co-pyrolysis is a promising technology that can facilitate the development of bioenergy and the clean production of petroleum industry. Currently, how to realize the amplification of the co-pyrolysis technology for industrial application is an urgent problem to be solved.

Keywords: oily sludge; biomass; co-pyrolysis; high quality product; polygeneration application