Development of high efficient desulfurization technique using ultra fine CaO prepared by cheap method

研究了以钙交换褐煤为吸附剂的高效脱硫新工艺。黄煤是一种澳大利亚褐煤，被选作离子交换。以碳酸钙（OH） _2和混凝土工业含钙废料为原料。将煤颗粒在钙料浆中浸泡混合一定时间，进行离子交换。约10%的钙很容易掺入黄煤中。研究发现，混凝土加工过程中产生的工业废渣是一种很有前途的钙离子交换原料。换钙煤对SO_2气的反应活性非常高，CaO的利用率达到90%以上，而在相同的实验条件下，天然石灰石的转化率不到30%。用水泥废渣制备的换钙煤的反应性与用Ca (OH) _2制备的换钙煤相似。在流化床燃烧室中发现了钙交换煤的高活性。换钙煤对SO_2和H_2S均有较好的脱硫效果。褐煤换钙脱硫技术不仅适用于流化床煤燃烧，也适用于流化床煤气化。

A new efficient desulfurization technique using a Ca-exchanged brown coal as a sorbent was developed. Yallourn coal, an Australian brown coal was selected for an ion-exchange. Ca (OH) _2 and Ca-containing waste from concrete industry were used as calcium raw materials. Ion-exchange was carried out by soaking and mixing coal particles in the slurry of calcium materials for a certain period. About 10wt% of Ca was easily incorporated into Yallourn coal. It was found that the industrial waste from concrete process was a promising one as a calcium raw material for the ion-exchange method. The reactivity of CaO produced from Ca-exchanged coal to SO_2 gas was extraordinary high and the CaO utilization of above 90% was achieved, while the conversion of natural limestone was less than 30% under the similar experimental conditions. The reactivity of Ca-exchanged coal prepared from the cement waste was similar to that of Ca-exchanged coal from Ca (OH) _2. The high activity of Ca-exchanged coal was recognized in a fluidized bed combustor. Ca-exchanged coal was quite effective for the desulfurization of not only SO_2 but H_2S.The desulfurization technique using Ca-exchanged brown coal is applicable to not only fluidized bed coal combustion but also fluidized bed coal gasification.