煤粉掺烧干化污泥的燃烧特性及能效分析

针对某电厂420 t/h四角切圆煤粉炉进行掺烧污泥的改造,根据煤与污泥掺混后在煤粉炉上的着火、稳燃、结渣等特性分析了煤粉炉掺烧干化污泥的可行性,并利用火用平衡分析方法对煤粉炉掺混不同比例、不同含水率污泥时锅炉效率及各受热面火用损情况进行了分析。结果表明,当污泥掺混比例小于1∶4时,泥煤混合燃烧特性与煤相似,且火用效率略大;污泥掺混大于该比例后,其灰熔点下降明显,有明显结渣倾向,且排烟损失显著增加。以上研究结果可为电厂掺烧干化污泥的可行性提供了必要的实验和理论依据。

Combustion Characteristics and Analysis of the Energy Efficiency of a Coal-fired Boiler Burning Coal Diluted and Mixed With Dried Sludge

For a construction project of a 420 t/h tangential pulverized coal-fired boiler,analyzed was the feasibility of the pulverized coal-fired boiler to burn coal diluted and mixed with dried sludge from such characteristics as ignition,steady combustion and slagging etc.and the exergy balance analytic method was used to analyze the efficiency of the boiler and the exergy loss of various heating surfaces when burning coal mixed and diluted with sludge in various proportions and water contents.The research results show that when the proportion of sludge mixed and diluted is less than 1:4,the sludge-coal blended combustion characteristics are similar to coal and meanwhile the exergy efficiency of the mixture is slightly higher than that of coal.After the proportion of sludge mixed and diluted is greater than 1:4,the ash melting point of the mixture sample will drop obviously,tend to slag conspicuously and the exhaust gas loss will increase remarkably.The foregoing can offer a necessary experimental and theoretical basis for analyzing the feasibility of a power plant to burn coal diluted and mixed with dried sludge.