Techno-Economic Analysis and Life Cycle Assessment of Five VGO Processing Pathways in China

The production of high-quality gasoline and petrochemicals using vacuum gas oil (VGO) as a raw material has tremendous industrial and economic significance. A comparative study for various VGO processing pathways in terms of their technoeconomic viability and environmental performance is presented. Five different techniques, including a novel technology, are proposed: (1) conventional fluid catalytic cracking, (2) deep catalytic cracking, (3) a novel technology, hydrogenation and two-stage riser catalytic cracking for maximizing the propylene (TMP) coupling process, (4) maximum production of petrochemicals by hydrocracking, and (5) production of benzene and p-xylene by hydrocracking. Detailed process models are developed for all of the five designs to obtain the mass and energy balances of each processing pathway. Technoeconomic analysis and life cycle assessment have been carried out. Moreover, key process parameters which affect each process have been recognized and optimized. The economic analysis shows that the hydrogenation and TMP coupling process is more profitable than the other processing pathways. The results of environmental performance analysis indicate that high-quality gasoline and light olefins manufactured from the catalytic-cracking-based process result in less life cycle greenhouse gas emissions and primary energy demand than hydrocracking-based processes on the basis of total output value per million Yuan.