燃煤电厂掺烧生活污泥燃烧及环保特性现场试验研究

Field Experimental Research on Characteristics of Mixed Domestic Sludge Combustion and Environmental Protection in Coal⁃fired Power Plant

为了得到燃煤电厂掺烧生活污泥燃烧及环保特性规律,基于国内某电厂的330 MW亚临界四角切圆燃煤锅炉,针对6个工况开展现场试验研究。结果表明:燃煤、污泥与混合后的燃料在成分含量上区别较大;掺烧污泥会导致锅炉燃烧温度与热效率降低,最大的降幅分别为28℃和0.19%,总体降幅较小;掺烧污泥后,飞灰与炉渣中重金属含量及氯含量稍微上升,不会明显提高结渣风险;掺烧污泥后,现有的净化工艺仍能确保常规烟气污染物的排放浓度能满足燃煤烟气超低排放要求;随着掺烧比例的提高,NO_(x)的排放量呈现先增加后降低的趋势,SO_(2)的排放量逐渐降低,粉尘颗粒的排放量稍微提高;掺烧污泥不会对二噁英类和重金属及其化合物等非常规烟气污染物造成明显影响,排放情况能够满足燃煤电厂限制要求;风烟系统各级风机用电量普遍随着掺烧污泥量增加而提升,最大的提升幅度为5.4A,适当调整后均能够正常运行。

In order to obtain the characteristics of domestic sludge combustion and environmental protection in coal⁃fired power plants,field tests were carried out under six working conditions based on the 330 MW subcritical tangentially coal⁃fired boiler of a power plant in China.The results show that there is a great difference in the composition content between coal burning,sludge and mixed fuel;and the mixed burning of sludge will lead to the decrease of boiler combustion temperature and thermal efficiency,with the maximum decrease of 28℃and 0.19%respectively,and the overall decrease is relatively small;after mixed with sludge,the contents of heavy metals and chlorine in fly ash and slag increase slightly,which can not significantly increase the risk of slagging;after mixed with sludge,the existing purification process can still ensure that the emission concentration of conventional flue gas pollutants can meet the requirements of ultra⁃low emission of coal⁃fired flue gas;with the increase of the proportion of mixed combustion,the emission of NO_(x) increases at first and then decreases,the emission of SO_(2) decreases gradually,and the emission of dust particles increases slightly;the mixed burning of sludge will not have a significant impact on unconventional flue gas pollutants such as dioxins,heavy metals and their compounds,and the discharge can meet the restrictions of coal⁃fired power plants;the electricity consumption of fans at all levels of the wind and smoke system generally increases with the increase of the amount of mixed burning sludge,and the maximum range of increase is 5.4A,which can operate normally after proper adjustment.