Performance analysis and multi-scenario decision of cogeneration system combined with gasifier under different mixing ratios

The gasification cogeneration system with biomass as input energy can help the development of clean heating in rural areas of northern China and implement the “Carbon Neutralization” policy. This research compared and analysed the effects of three typical biomass feedstocks (corncob, wheat straw, and bark) on the system performance under different mixing ratios and proposes the decision-making suggestions of corresponding mixing ratios under different scenarios with the performance evaluation index as reference. The results of the performance analysis of the system were as follows: the optimal equivalence ratio at the mcc:mws:mb of 1:1:1 was 0.325, and the corresponding cold gas efficiency was 79.65%. The highest calorific value of syngas was 4.691 MJ/Nm3 at the mcc:mws:mb of 1:5:1, while the lowest biomass feedstock consumption was 20.1 kg/h at the mcc:mws:mb of 1:5:10. The highest waste heat of jacket water and exhaust gas was 15.94 kW and 17.6 kW at the mcc:mws:mb of 1:5:10, and the highest cooling capacity was 6 kW at the mcc:mws:mb of 1:5:10. For the scenario with high energy efficiency requirements and insensitive to price, the recommended mixing ratio was mcc:mws:mb =1:5:10, and corresponding energy and exergy efficiency were as high as 22.24% and 15.44%. The article has certain significance for expanding the treatment and utilization of biomass feedstocks in multiple scenarios.