Cao Haihua, Liu Wei, Xu Jingcheng, Liu Jia, Huang Juwen, Huang Xiangfeng, Li Guangming
College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment of Education Ministry, Tongji University, Room 302, No. 1239 Siping Road, Shanghai 200092, China E-mail:
Water Sci Technol. 2018 Feb;77(3-4):960-970. doi: 10.2166/wst.2017.604.
Co-processing lime-dried sludge (LDS) in cement kilns is an appropriate technique to solve the problem of LDS disposal and promote the sustainable development for cement industry. However, there were limited studies that investigated the effects of feeding points on product quality and cement kiln emissions. In this study, simulated experiments were conducted by dividing the feeding points into high-temperature zones (HTZs) and raw mill (RM). Cement quality and major cement kiln emission characteristics were comprehensively investigated. The results showed that in terms of burnability, compressive strength and microstructure, the optimum co-processing amount of LDS were 9 wt% when feeding at RM, while 6% when feeding at HTZs. Meanwhile, the organic emissions of RM samples were mainly low environmental risk compounds of amides and nitrogenous heterocyclic compounds. Inorganic gaseous pollutions of NO and SO, respectively, were 8.11 mg/g DS and 12.89 mg/g DS, compared with 7.61 mg/g DS and 4.44 mg/g DS for HTZs. However, all the cement kiln emissions concentration were still much lower than standard requirements. Overall, RM had a bigger LDS co-processing capacity and higher, but acceptable, cement kiln emissions. Feeding LDS via RM could dispose larger amounts of sludge and provide more alternative materials for cement manufacturing.
在水泥窑中协同处理石灰干燥污泥（LDS）是解决LDS处置问题并促进水泥行业可持续发展的一项合适技术。然而，研究喂料点对产品质量和水泥窑排放影响的研究有限。在本研究中，通过将喂料点分为高温区（HTZs）和生料磨（RM）进行模拟实验。综合研究了水泥质量和主要水泥窑排放特性。结果表明，在易烧性、抗压强度和微观结构方面，当在RM喂料时，LDS的最佳协同处理量为9 wt%，而在HTZs喂料时为6%。同时，RM样品的有机排放主要是酰胺和含氮杂环化合物等低环境风险化合物。NO和SO的无机气态污染物分别为8.11 mg/g DS和12.89 mg/g DS，而HTZs分别为7.61 mg/g DS和4.44 mg/g DS。然而，所有水泥窑排放浓度仍远低于标准要求。总体而言，RM具有更大的LDS协同处理能力和更高但可接受的水泥窑排放。通过RM喂入LDS可以处理更多的污泥，并为水泥生产提供更多替代材料。
