The semi dry process reflects the different selection of the whole desulfurization process and desulfurization materials, especially the semi dry process of desulfurization in wet conditions and solving desulfurization materials in dry conditions. It not only has the advantages of sensitive response and high desulfurization efficiency of wet desulfurization process, but also has the advantages of dry desulfurization process without sewage and wastewater discharge and solving desulfurization materials in dry conditions. It is the key development prospect of sulfur removal process.

1、喷雾器半干法

1. Spray semi dry method

工艺详细介绍

Detailed introduction of process

喷雾器半干法是运用喷雾干燥机基本原理，将吸附剂浆体做雾化喷到脱硫塔。在脱硫塔内，吸附剂在与烟尘中的二氧化硫发上化学变化的另外，消化吸收烟尘中的发热量使吸附剂中的水份挥发干躁，脱硫反映后的废料以干态排出来。

The spray semi dry method uses the basic principle of the spray dryer to spray the adsorbent slurry to the desulfurization tower. In the desulfurization tower, the adsorbent changes chemically with the sulfur dioxide in the flue dust. In addition, the heat in the flue dust is digested and absorbed to make the water in the adsorbent evaporate and dry, and the waste after desulfurization is discharged in a dry state.

优点和缺点

merits and demerits

工艺步骤比白云石-熟石膏法简易，项目投资也较小。缺陷是脱硫率较低，一般为70-80%、实际操作延展性较小、钙硫比较高，运作成本增加、副产品没法运用。

The process steps are simpler than dolomite gypsum method, and the project investment is also small. The defect is that the desulfurization rate is low, generally 70-80%, the actual operation ductility is small, the calcium sulfur is relatively high, the operation cost increases, and the by-products cannot be used.

2、炉内喷钙尾端加湿活*法

2. Calcium Spraying in furnace, tail end humidification method

工艺详细介绍

Detailed introduction of process

将研磨石灰石粉用气力输送系统方式 喷涌到炉内上端温度为900~1250℃的地区，CaCO3马上溶解并与烟尘中的SO2和小量的SO3反映转化成CaSO4。在内炉内中未反映的CaO与喷到的水反映转化成Ca(OH)2,SO2与转化成Ca(OH)2快速响应转化成CaSO3,有一部分被氧化成CaSO4。

The ground limestone powder is sprayed into the area with the temperature of 900 ~ 1250 ℃ at the upper end of the furnace by means of pneumatic conveying system. CaCO3 is dissolved immediately and reflected with SO2 and a small amount of SO3 in the smoke and dust and transformed into CaSO4. Cao not reflected in the inner furnace is converted into Ca (OH) 2 by reaction with the injected water, SO2 is converted into Ca (OH) 2 by rapid response and converted into CaSO3, and some of it is oxidized into CaSO4.

优点和缺点

merits and demerits

优势是机器设备项目投资较小，可是在提升炉内喷钙标准下，CaCO3热裂解转化成基酶CaO，尽管无法立即在炉膛内获得很高的脱硫率，但炉内未与SO2反映的CaO在加热炉后侧洒水加湿、水合为Ca(OH)2，超低温下可再度与SO2反映，能明显提升系统软件脱硫率和钙基吸着剂使用率，但脱硫率较一般在60%～70%。总的来看,炉内脱硫率和钙基吸着剂使用率都不足高，其技术经济发展特性的竞争能力不足强。

The advantage is that the investment of machinery and equipment projects is small. However, under the standard of calcium injection in the furnace, CaCO3 is thermally cracked and converted into basic enzyme Cao. Although it is impossible to obtain a high desulfurization rate in the furnace immediately, Cao not reflected with SO2 in the furnace is watered and hydrated to Ca (OH) 2 at the back of the heating furnace. It can be reflected with SO2 again at ultra-low temperature, which can significantly improve the desulfurization rate of system software and the utilization rate of calcium based sorbent, but the desulfurization rate is generally 60% ~ 70%. On the whole, the desulfurization rate in the furnace and the utilization rate of calcium based sorbent are not high enough, and the competitiveness of its technical and economic development characteristics is not strong enough.