Hui Jicheng, Lin Jiangong, Zhu Shujun, Li Zhaoyang, Zhang Xiaoyu, Cao Xiaoyang, Zhu Jianguo, Lyu Qinggang
North China Electric Power University, Beijing 102206 China; State Key Laboratory of Coal Conversion, Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190 China.
State Key Laboratory of Coal Conversion, Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190 China; Shanxi Datong University, Datong 037009 China.
Waste Manag. 2025 Mar;195:200-208. doi: 10.1016/j.wasman.2025.02.012. Epub 2025 Feb 8.
The improper disposal of coal gasification fly ash (CGFA) and coal gangue (CG) is highly susceptible to environmental pollution. Preheating combustion is a proven technology for the efficient combustion of solid fuels. On the basis of this technology and combining the complementary physical properties of CGFA and CG, the synergistic combustion of these two typical solid wastes is expected to occur. In this study, the preheating modification and co-combustion characteristics of CGFA and CG with different blending ratios were investigated. The evolution of the physicochemical structure of the activated char was analyzed via a particle size analyzer, scanning electron microscope, N adsorption-desorption and Raman spectroscopy. The results indicated that stable operation of the preheated combustion system could be achieved when the blending ratio of CG was 25 %-50 %. The apparent structure of the blended fuel can be improved by CGFA, while the specific surface area and chemical reactivity of the resulting char can be increased significantly. The highest activity of the preheated char was achieved at a blending ratio of 25 % (R = 25 %). In addition, there was a synergistic effect between the fixed carbon in CGFA and the volatiles in CG during co-combustion. The combustion efficiency of the blended fuel was improved at blending ratios of 25 % to 50 %. With the comprehensive evaluation of preheating modification and co-combustion characteristics, the optimal blending ratio of CG was R = 25 %. In this case, the NO and NO emissions were 121 mg/cm (@6% O) and 14 mg/cm (@6% O), respectively.
煤气化粉煤灰（CGFA）和煤矸石（CG）的不当处置极易造成环境污染。预热燃烧是一种经证实的固体燃料高效燃烧技术。基于该技术并结合CGFA和CG的互补物理性质，有望实现这两种典型固体废物的协同燃烧。本研究考察了不同掺混比例的CGFA和CG的预热改性及共燃特性。通过粒度分析仪、扫描电子显微镜、N吸附-脱附和拉曼光谱分析了活性焦的物理化学结构演变。结果表明，当CG的掺混比例为25%-50%时，预热燃烧系统可实现稳定运行。CGFA可改善混合燃料的表观结构，同时显著提高所得焦炭的比表面积和化学反应活性。在掺混比例为25%（R=25%）时，预热焦炭的活性最高。此外，CGFA中的固定碳与CG中的挥发物在共燃过程中存在协同效应。在25%至50%的掺混比例下，混合燃料的燃烧效率得到提高。综合评估预热改性和共燃特性，CG的最佳掺混比例为R=25%。在此情况下，NO和NO排放分别为121mg/cm（@6%O）和14mg/cm（@6%O）。
