Techno-economic analysis of co-processing of vacuum gas oil and algae hydrothermal liquefaction oil in an existing refinery

Co-processing of ligno-cellulosic bio-oil and vacuum gas oil (VGO) in an existing refinery for the production of gasoline with renewable carbon has demonstrated a good technical and economic feasibility and the potential to partial replace the petroleum-derived gasoline. The co-processing of VGO and algae hydrothermal liquefaction oil (AHTLO) has drawn attention and showed the highly technical feasibility. However, the economic performance for the co-processing of VGO and AHTLO remains unclear. In this work, techno-economic analysis for VGO and AHTLO co-processing is conducted to evaluate its overall economics and also obtain the optimal algal production technology from algal turf scrubbers (ATS) and open raceway ponds (ORP). Two co-processing scenarios integrated the two algal production technologies, ATS scenario and ORP scenario, are proposed to illustrate their differences. The results show that minimum gasoline selling price of ATS scenario is only $3.11 per gallon while the one of the ORP scenario reaches $3.24 per gallon. The VGO cost still takes near 60% of the gasoline price. The comparisons between the co-processing gasoline and petroleum-derived gasoline show that the saved capital investment is the main reason why the production cost of the co-processing gasoline can be reduced. The sensitivity analysis demonstrates that the fuel yield, VGO and diesel prices and the capacity of the co-processing FCC to be the important factors in the economic viability. Gasoline from the co-processing of VGO and AHTLO may be a potential way to partial replace petroleum-derived gasoline in certain circumstances.