Study on a new sulfur fixation combustion-supporting agent for coal
In order to improve the coal utilization of rotary kiln for baking siderite and obtain efficient and practical new sulfur fixation combustion-supporting agents, the paper choose the coal used in production in the experiment, the orthogonal test method and thermogravimetric analysis was used to study the coal ignition and combustion rate, and then analyzes the type of combustion-supporting agents, adding amount and particle size of coal influence on the combustion ratio, and it indicated that adding CuCl2 · H2O by 0.3% into the coal below 180 mesh can reduce coal's ignition point for 41 °C and raise the burn rate to 79.23%; we researched that sulfur fixation sorbent types, Ca / S molar ratio, combustion temperature, particle size of coal and pretreatment time on the sulfur-fixing rate, and the CaO was chosen as the sulfur fixation sorbent finally, Ca / S is 2.5, the combustion temperature is 900 °C, the coal particle size is 180 mesh, pretreatment time 30min; under these conditions the sulfur-fixing rate is 51.48%; based on the single test on calcium-based sulfur retention agent, and investigated the influence of the type of sulfur fixation additives, adding volume and pretreatment time on the sulfur-fixing rate, it was found that the Na2CO3 is most promoting in the four. The results showed that adding 0.3% Na2CO3 in the coal, pretreated for 30min, the fixation efficiency of CaO can be increased to 68.17%; comprehensive test results on the three groups to determine the composition of sulfur fixation combustion-supporting agents for the CaO, Na2CO3, CuCl2 · H2O, the ratio is 86%: 7%: 7%. The integration of sulfur combustion test results showed that the addition of 2.0% sulfur fixation combustion-supporting agents into coal can lower the ignition point of 39 °C, improve combustion ratio to 72.51%, and improve the sulfur-fixing rate to 61.32%.