干法脱硫过程多数属气固反应，速度相对较低，烟气在反应器中的流速较慢，延长反应时间，故设备较庞大，但脱硫后的烟气降温较少或不降温，故不需再加热（耗能少），即可满足排放扩散要求。此外，二次污染少、无结垢、堵塞、可靠性高。

The process of dry desulfurization is mostly gas solid reaction, the velocity is relatively low, the flow velocity of the flue gas in the reactor is slow and the reaction time is prolonged, so the equipment is large, but the flue gas after the desulphurization is less cooling or not cooling, so it does not need to be reheated (less energy consumption), which can satisfy the demand of emission diffusion. Besides, the two pollution is less, no scaling, blockage and high reliability.

1、粉煤灰干式脱硫

1. Dry fly ash desulphurization

脱硫剂由粉煤灰、消石灰和石膏为原料，制成颗粒状将它们装在吸收塔中形成移动层。当脱硫剂在塔中自上而下地移动时，其中的消石灰氢氧化钙与烟气中的二氧化硫反应生成石膏，而脱硫剂中的煤灰和石膏则起活性媒体的作用。用过后的脱硫剂还可以作为生产脱硫剂的原料再被重新利用。

The desulphurizer is made from fly ash, hydrated lime and gypsum as raw material and granulated into a absorber. When the desulfurizer moves up and down from the tower to the tower, the calcium hydroxide of the desulfurizer reacts with the sulfur dioxide in the flue gas to produce gypsum, while the fly ash and gypsum in the desulfurizer play the role of active media. The desulfurizer after use can also be used as raw material for producing desulfurizer.

2、BF移动床活性炭脱硫

2 and BF moving bed activated carbon desulphurization

用活性炭作脱硫剂，在脱硫移动床中与约100℃烟气错流接触，以脱除二氧化硫，脱硫率90％以上。吸附了二氧化硫的活性炭在再生移动床中与 500～ 600 ℃热砂（或其它热载）体合，被炭还原成二氧化硫逸出，用于制硫酸，向烟气中添加氨用双层床处理，可同时脱除80%的二氧化氮。

Activated carbon is used as desulfurizer to cross the contact with flue gas at about 100 degrees in a desulphurization mobile bed to remove sulfur dioxide, and the desulfurization rate is over 90%. The activated carbon adsorbed sulfur dioxide in the regenerated mobile bed is combined with hot sand (or other hot load) at 500~600 C, and is reduced to sulfur dioxide by carbon. It is used to make sulphuric acid, and the ammonia is added to the flue gas to be treated with a double layer bed, and 80% nitrogen dioxide can be removed at the same time.

3、喷雾千燥法

3. Spray drying method

它是七十年代发展起来的。它是用石灰奖作脱硫剂，用雾化器将石灰浆水溶液喷入吸收塔内，石灰浆以极细的雾滴与烟气中的二氧化硫接触。并发生化学反应，生成亚硫酸钙和硫酸钙。利用烟气中的热量使雾滴的水份汽化，干燥后的粉未随脱硫后的烟气带走，用除尘器捕集，脱硫率70～90％；当Ca／S—1.5时，脱硫率为85％，这是～种在湿状态下脱硫。在干状态下处理脱硫产物的方法，亦称为半干式。喷雾干燥加布袋除尘，脱硫率可达90％以上．允许煤含硫量可达3％，可与湿法相竞争，这种方法的主要特点是；因吸收塔出来的废料是干的，与湿式石灰石法相比．省去了庞大的废料处理系统，使工艺流程大为简化，该法的关键技术是石灰石浆液的雾化器和吸收干燥塔。现在使用广泛的是离心转盘雾化器。因此，该法在我国应用前景好。

It was developed in 70s. It uses lime as a desulphurizer, and uses atomizer to spray lime solution into the absorption tower. The lime slurry contacts the sulfur dioxide in the flue gas with very fine droplets. A chemical reaction was made to form calcium sulfite and calcium sulphate. Using the heat in the flue gas to vaporize the water of the droplet, the dried powder is not taken away with the flue gas after the desulphurization, and the desulfurization rate is 70 ~ 90%. When Ca / S - 1.5, the desulfurization rate is 85%, which is the kind of desulfurization in the wet state. The method of treating desulfurization products under dry condition is also called semi dry. The rate of desulphurization can reach more than 90%. The sulfur content of the allowed coal can reach 3%. It can compete with the wet process. The main feature of this method is that the waste from the absorption tower is dry. Compared with the wet limestone method, the huge waste disposal system is saved and the process is simplified. The key technology is the atomizer of limestone slurry and the absorption drying tower. The most widely used is the centrifugal rotary atomizer. Therefore, the application of this method is good in our country.

4、电子束照射法

4. Electron beam irradiation

其原理是：含水分的烟气在电子束的照射下，烟气中的水被激活裂解成HO、O等强氧化剂，能迅速将二氧化硫和二氧化氮氧化成三氧化硫和五氧化二氮，再与添加的氨化合成硫铵和硝铵，用除尘器收集作为肥料付产品。脱硫率90％，脱硝率80％。整套装置电耗高，约占厂发电量的10％。

The principle is that water containing water is irradiated by electron beam, and the water in the flue gas is activated cracking into strong oxidants such as HO, O and so on. It can quickly oxidize sulfur dioxide and nitrogen dioxide into three sulphur oxide and nitrogen pentoxide, and then synthesize ammonium sulphate and ammonium nitrate with the added ammoniation. The desulphurization rate is 90%, and the denitrification rate is 80%. The whole unit has a high power consumption, accounting for about 10% of the plant's power generation.