Research On Catalytic Cracking Of Tar Derived From Biomass Gasification Process

With energy issues being more and more serious, biomass gasification technology has been very promising since it can improve the energy quality and utilization efficiency of biomass. The final purpose of the biomass gasification progress is to obtain high-quality flammable gas as much as possible. However, the tar in biomass can seriously affect the quality of biomass gasification gas, which makes the removal of tar from biomass a hot topic.In this paper, we first briefly introduce the production and damage of biomass tar, as well as the primary methods of tar removal at present, and then analyze of the mechanism of catalytic cracking of tar and tar removal catalytic cracking program in-depth. By analyzing the experimental data from the catalytic cracking of tar exists in corn stalk pyrolysis gas, the impact of the catalyst size and the catalytic pyrolysis temperature on the catalytic cracking of tar are also discussed. Through the analysis of the experimental data, we can find that when the catalytic pyrolysis temperature is in a certain range, it is more conducive to the conversion of tar if the limestone we used as the catalyst is with a smaller size. Meanwhile, the rate of gas production can be increased with lower coke yield, and the catalyst service life can also be prolonged. In order to achieve the best catalytic cracking effect of tar, we need to make a large number of experiments to find the optimal size of limestone catalyst and the best catalytic cracking temperature, which is not realistic. Therefore, based on the least squares support vector machine theory, this paper proposes a model for catalytic cracking of tar removal straw gasification, and verifies the feasibility of the model. Finally, with the proposed model, we obtained the Pareto solution set of multi-objective optimization problem by genetic algorithm of parallel selection, and thus the best catalytic cracking temperature and the optimal size of limestone in catalytic cracking of straw gasification tar with limestone as the catalyst,which can provide references for improving the catalytic cracking rate of tar and natural life of catalyst in practical engineering applications.