城市污泥与混矸煤混燃特性的实验研究

Study of co-combustion characteristic of sewage sludge and coal gangue mixed with weathered coal

利用热重分析仪研究不同掺烧比例、不同钙硫比下低热值混矸煤与污泥的着火稳定性和综合燃尽特性。采用Coats-Redfern积分法确定污泥与煤混烧过程中化学动力学参数。结果表明:污泥与煤样的混烧特性从总体上表现为污泥和煤样共同作用的结果,低热值混矸煤中适当掺混污泥可以提高热失重率,改善低热值混矸煤的着火特性,达到更好的燃烧效果,当污泥的掺烧比为10%左右时,综合燃烧性能最好。Ca/S摩尔比对煤和污泥燃烧也有很大的影响,随着Ca/S摩尔比的增加,混合燃料的着火点和燃尽温度均增加,燃烧特性指数先变小再增大,可以得出为了增加脱硫的效果而增加Ca/S摩尔比,对混合燃料的燃烧起到负面的作用,所以需要寻求一个最佳的Ca/S摩尔比。其研究结果可为掺烧污泥的循环流化床锅炉的运行提供参考。

Combustion characteristics of sewage sludge and coal gangue mixed with weathered coal were studied by thermos gravimetric analyzer with different mixng ratios and calcium-sulphur ratios. The kinetics analysis of the mainly weightlessness stage of fuel was conducted using the Coats-Redfern integral method. Results show that, the combustion characteristics reached the highest point with the mixing ratio of 10%. Calcium and sulfur have a great influence on coal and sludge combustion. With the increase of Ca/S molar ratio, the ignition and ignition temperature of the mixed fuel are increased, and the combustion characteristic index increases first and then increases. Increasing the Ca/S molar ratio by increasing the desulfurization effect has a so an optimum Ca/S molar ratio is required. The operation of circulating fluidized bed boiler. negative effect on -he combustion of the mixed fuel, results of the study can provide a reference for the