Upgrading of heat carrier oil derived from liquid-phase pyrolysis via fluid catalytic cracking

Abstract

Second generation biofuel technologies are well investigated to extend the amount of sustainable biofuels. One of the most important criterions for biofuels is their profitability. The bioCRACK process is a new and innovative biomass-to-liquid concept to produce advanced biofuels by liquid-phase pyrolysis. A refinery integrated pilot plant was built up at the OMV refinery in Schwechat (Austria) to provide data for up-scaling. The objective of this publication was to test the suitability of different processed heat carrier oils derived from the bioCRACK process as feedstock for the FCC process. Vacuum gas oil – a typical feedstock for fluid catalytic cracking – was used as heat carrier oil. Different case studies were evaluated, whereas spruce wood and wheat straw were used as feedstock for pyrolysis. All experiments were conducted in a fully continuous small scale pilot plant with internally circulating fluidized bed design. In general, the obtained results show a high conversion efficiency for all performed case studies. Thereby the yield of coke is increased a little. The investigation confirmed that the total fuel yield can be improved even more by additional hydrotreatment. It turned out that the use of a pre-hydrotreated vacuum gas oil for pyrolysis leads to the highest conversion level.