North China University of Water Resources and Electric Power, Zhengzhou 450011, China.
North China University of Water Resources and Electric Power, Zhengzhou 450011, China; Institute of Engineering Thermophysics, Chinese Academy of Science, Beijing 100190, China.
Waste Manag. 2020 Mar 15;105:84-91. doi: 10.1016/j.wasman.2020.01.039. Epub 2020 Feb 6.
The utilization of agricultural wastes in existing pulverized coal power plants is an attractive option to alleviate environmental pollution and reduce over-exploitation of fossil fuels. A coupled system model of biomass gasification coupled to a coal-fired boiler is established in Aspen Plus and successfully validated by experimental data. A 20 t/h straw gasifier operates at the rated capacity and the straw gas is introduced to the boiler running at different loads. The co-firing ratio increases with the reduction of boiler load. Results indicate that the main parameters, such as furnace combustion temperature, flue gas temperature, and NO and SO emission decrease with the reduction of boiler load. Compared to pure coal combustion, co-firing can reduce the furnace combustion temperature and increase the flue gases temperature. More importantly, the coal consumption, and NO and SO emissions are reduced at all loads, especially at lower loads. The excess air ratio should be adjusted to obtain the optimum combustion performance in the furnace, but there is still a slight drop of around 0.2% in boiler efficiency when co-firing. Meanwhile, the coupled system efficiency at various loads can reach slightly more than 84% under optimum conditions.
利用农业废弃物在现有的煤粉发电厂是一个有吸引力的选择，以减轻环境污染和减少对化石燃料的过度开采。生物质气化与煤粉锅炉耦合的耦合系统模型在 Aspen Plus 中建立，并通过实验数据成功验证。20t/h 的秸秆气化炉在额定容量下运行，秸秆气被引入到不同负荷下运行的锅炉中。掺烧比例随着锅炉负荷的降低而增加。结果表明，随着锅炉负荷的降低，炉膛燃烧温度、烟气温度、NO 和 SO 排放等主要参数降低。与纯煤燃烧相比，掺烧可以降低炉膛燃烧温度，提高烟气温度。更重要的是，在所有负荷下，特别是在较低负荷下，煤耗、NO 和 SO 排放量都有所减少。过量空气比应进行调整，以获得炉膛内最佳的燃烧性能，但在掺烧时，锅炉效率仍有轻微下降，约为 0.2%。同时，在最佳条件下，各种负荷下的耦合系统效率可达到略高于 84%。
