车间除尘设备的净化工艺流程解析
Analysis of purification process of dedusting equipment in workshop
(1)吸收装置：吸收装置基本上可以分为三***类型，即填料塔、板式塔、喷淋塔(包括文丘里管与喷射泵)。另外还有一些***殊的塔型如湍球塔，见图2-19.填料塔是在塔内装有一定高度的填料层，液体从塔***沿填料表面呈薄膜状向下流动，气体则呈连续相由下向上同液膜逆流接触，发生传质过程.板式塔是在塔内装有一定数量的塔板，气体以鼓泡或喷射形式穿过板上液层时，进行气液接触.喷淋塔是在塔内气液直接接触。
(1) absorption device: the absorption device can be basically divided into three types, namely, packing tower, plate tower, spray tower (including venturi tube and jet pump). In addition, there are some special tower types, such as turbulent sphere tower, as shown in Figure 2-19. The packed tower is equipped with a certain height of packing layer. The liquid flows down the packing surface in a film shape from the top of the tower, while the gas is in a continuous phase and contacts with the liquid film in reverse flow from the bottom to the top. Mass transfer occurs in the plate tower. A certain number of plates are installed in the tower, when the gas passes through the liquid layer on the plate in the form of bubbling or spraying The spray tower is in direct contact with the gas and liquid in the tower.
(2)除尘处理：在吸收之前，若能专门设置高效的除尘器(如电除尘器等)，那是***理想的，然而也可能是不太经济的.若能在吸收时考虑在清除气态污染物的过程中，一同清除烟气，那是较为理想的.如在吸收塔前增设预洗涤塔;或只用一个塔，下段为预洗段、上段为吸收段;或研究出既能除尘又能吸收气体的湿式洗涤器，不过这二者的设计要求是不***一致的，应予充分注意。
(2) dedusting treatment: before absorption, it is the most ideal if a high-efficiency deduster (such as electrostatic precipitator) can be specially set up, but it may not be economical. It is more ideal if the flue gas can be removed together in the process of removing gaseous pollutants during absorption. For example, a pre washing tower is added in front of the absorption tower, or only one tower is used, the lower section is the pre washing section, and the upper section is the suction section The design requirements of the wet scrubber, which can not only remove dust but also absorb gas, should be paid more attention.
(3)预冷却处理：吸收操作希望在较低温度下进行，但有的废气温度较高，这就豁要在吸收之前进行烟气的冷却，其方法可采用换热器，但设备庞***;也可用水直喷人烟道增湿降温，但易形成酸雾腐蚀设备或阻塞管道;目前使用较广的是用预洗涤塔或预洗涤段，效果较***。
(3) pre cooling treatment: the absorption operation is expected to be carried out at a lower temperature, but some exhaust gases have a higher temperature, so it is necessary to cool the flue gas before absorption. The method can be heat exchanger, but the equipment is huge; it can also be used to humidify and cool the flue gas by direct injection of water, but it is easy to form acid mist to corrode the equipment or block the pipeline; at present, the pre washing tower or pre washing section is widely used, with better effect OK.
(4)净化气体的热处理：在冷却增湿处理***量烟气和某些不利的气象条件下，将发生“白烟’，白烟在没有充分上升、扩散之前就已回到地面，会产生较高浓度的污染.防止白烟的措施之一是设置尾部撇烧护，嫩烧天然气或重油，使少量燃气混人净化气中，这种效果较***。
(4) heat treatment of purified gas: under the condition of cooling and humidifying a large number of flue gas and some unfavorable meteorological conditions, "white smoke" will occur, and white smoke will return to the ground before fully rising and diffusing, which will produce high concentration of pollution. One of the measures to prevent white smoke is to install tail skimming protection, tender burning of natural gas or heavy oil, so that a small amount of gas is mixed with purified gas, which has a better effect OK.
(5)废液处理：吸收了气态污染物的富液如果丢弃，不仅浪费了资源，而且造成了二次污染、所以，必须经济合理地对废液进行处理和利用如吸收了废气中so1的碱液，可以用加热和减压再生的方法，恢复吸收剂的能力，而同时又排放出硫酸副产品;也可以用浓缩富液和结晶分离的方法，获得亚硫酸钠副产品，这些都达到了废物资源化的目的。
(5) waste liquid treatment: if the rich liquid absorbed gaseous pollutants is discarded, it will not only waste resources, but also cause secondary pollution. Therefore, it must be treated and utilized economically and reasonably. For example, if the alkali liquid absorbed SO1 in the waste gas can be regenerated by heating and reducing pressure to restore the capacity of the absorbent, and at the same time, the byproduct of sulfuric acid can be discharged; it can also be used to concentrate the rich liquid and The method of crystal separation and the by-product of sodium sulfite have achieved the goal of waste recycling.
