Experimental study on co-pyrolysis and gasification of biomass with deoiled asphalt

The behavior of co-pyrolysis and gasification of biomass and deoiled asphalt (DOA) was investigated. The co-pyrolysis of three biomasses and DOA reflected no obvious synergetic effect on the char yield, but the char's graphite degree reduced greatly. For the DOA was melted and stuck to the biomass surface during pyrolysis, the co-pyrolysis char showed an obvious agglomeration. The gasification rate of the co-pyrolysis chars was greatly increased by the addition of biomass, and the gasification curve were much similar to that of a homogenous char, indicating the blends were quite uniform and the alkali and alkaline earth metals in biomass could catalyze DOA gasification greatly. Sunflower stalk which has the highest potassium content and mineral content promoted the gasification rate best. Kinetic analysis showed that the average E values of the co-pyrolysis chars increased compared with the pure biomass char. The co-gasification of DOA and biomass is a good choice for disposing DOA. •Co-pyrolysis of biomass and DOA does not show synergetic effect on the char yield.•DOA melt and stuck to biomass surface causes the char an obvious agglomeration.•Synergetic effect is observed during gasification of the co-pyrolysis chars.•Co-gasification of DOA and biomass is a good choice for disposing DOA.