脫硫劑通常是指從燃料、原料或其他材料中去除游離硫或硫化物的藥劑。在污染物的控制和處理中,主要指用于去除廢氣中硫氧化物的藥劑。脫硫劑的選擇直接取決于工藝流程。一種工藝可以使用一種或兩種脫硫劑。有些工藝可以回收部分脫硫劑,然后補充。在選擇之前,我們應(yīng)該充分了解脫硫劑的具體類型?現(xiàn)在讓我們向您介紹一下。
Desulfurizer usually refers to the agent that removes free sulfur or sulfide from fuel, raw material or other materials. In the control and treatment of pollutants, it mainly refers to the agent used to remove sulfur oxides in waste gas. The selection of desulfurizer directly depends on the process flow. One or two desulfurizers can be used for one process. Some processes can recover some desulfurizers and then supplement them. Before selection, we should fully understand the specific type of desulfurizer? Now let's introduce it to you.
1、鈣基脫硫劑
1. Calcium-based desulfurizer
鈣基脫硫劑廣泛應(yīng)用于脫硫。常見的鈣基脫硫劑包括石灰、熟石灰、電石渣、石灰石和白云石,也可以從富含鈣的工業(yè)廢物和原料中獲得。鈣基脫硫劑具有來源廣、原料易得、成本低、脫硫效率高等優(yōu)點,被廣泛應(yīng)用于煙氣脫硫技術(shù)和燃燒過程脫硫技術(shù)中。固硫產(chǎn)品在1100℃以下具有良好的耐高溫分解性能。
Calcium-based desulfurizers are widely used in desulfurization. Common calcium-based desulfurizers include lime, hydrated lime, carbide slag, limestone and dolomite, and can also be obtained from industrial wastes and raw materials rich in calcium. Calcium-based desulfurizer is widely used in flue gas desulfurization technology and combustion process desulfurization technology due to its advantages of wide source, easy availability of raw materials, low cost and high desulfurization efficiency. The sulfur fixation product has good high-temperature decomposition resistance below 1100 ℃.
不同的鈣基脫硫劑具有不同的脫硫效果。在爐內(nèi)噴鈣脫硫中,在相同鈣硫比下,石灰石的脫硫效率較低,熟石灰的脫硫效率較高。這是因為當Cao水合為Ca(OH)2時,其比表面積會增加,孔徑分布會更好,而Ca(OH)2的熱分解溫度很低,分解為Cao時,其比表面積會增加,從而提高脫硫效率。
Different calcium-based desulfurizers have different desulfurization effects. In the process of calcium injection desulfurization in the furnace, the desulfurization efficiency of limestone is lower and that of hydrated lime is higher under the same calcium sulfur ratio. This is because when CaO is hydrated to Ca (OH) 2, its specific surface area will increase and the pore size distribution will be better, while the thermal decomposition temperature of Ca (OH) 2 is very low. When decomposed to CaO, its specific surface area will increase, thus improving the desulfurization efficiency.
1、Cao基鈣脫硫劑
1. Cao-based calcium desulfurizer
許多企業(yè)使用的早期Cao基脫硫劑主要是由約90%的石灰和5%~10%的螢石組成的混合脫硫劑。在活性石灰中加入螢石和鋁可以顯著提高脫硫效果。石灰是一種容易獲得的原料,原料充足,低廉。但石灰基脫硫劑用量大,渣量大,處理周期長。它還反映了鐵水溫度較高時的高脫硫率。
The early Cao-based desulfurizer used by many enterprises is mainly a mixed desulfurizer composed of about 90% lime and 5%~10% fluorite. Adding fluorite and aluminum to active lime can significantly improve the desulfurization effect. Lime is an easily available raw material with sufficient raw materials and low price. However, the amount of lime based desulfurizer is large, the amount of slag is large, and the treatment cycle is long. It also reflects the high desulfurization rate when the hot metal temperature is high.
2、CaC2基鈣脫硫劑
2. CaC2-based calcium desulfurizer
電石(CaC2)具有很強的脫硫能力。研究表明,鐵水溫度為1350℃時,電石粉脫硫反應(yīng)的平衡常數(shù)較高。電石、干煤粉、鎂或氧化鈣在工業(yè)中被廣泛使用。然而,電石容易與空氣中的水分反應(yīng)生成乙炔氣體,乙炔氣體易燃易爆。因此,電石加工、運輸、儲存和使用過程中對措施的要求很高,造成加工困難。不能滿足深度脫硫的要求。
Calcium carbide (CaC2) has strong desulfurization ability. The results show that the equilibrium constant of calcium carbide desulfurization reaction is higher when the temperature of molten iron is 1350 ℃. Calcium carbide, dry pulverized coal, magnesium or calcium oxide are widely used in industry. However, calcium carbide is easy to react with water in the air to generate acetylene gas, which is flammable and explosive. Therefore, the requirements for safety measures in the process of carbide processing, transportation, storage and use are very high, resulting in processing difficulties. It cannot meet the requirements of deep desulfurization.
2、鈉基脫硫劑
2. Sodium based desulfurizer
鈉基化合物用作濕法洗滌工藝(Na2CO3)和爐內(nèi)噴射和管道噴射(NaHCO3)工藝中的脫硫劑。特別是廣泛應(yīng)用于小型電廠和工業(yè)鍋爐。該工藝投資少,脫硫效果好。當ca/s=1.4~2.2時,脫硫率可達70%,脫硝率可達10%~20%。堿分解的熔融氧化鈉具有很強的腐蝕性,氧化鈉的揮發(fā)污染環(huán)境。純堿脫硫產(chǎn)生的爐渣具有良好的流動性,很難去除爐渣。蘇打水的也相對較高。因此,純堿作為脫硫劑已十分少見。
Sodium compounds are used as desulfurizers in wet scrubbing process (Na2CO3) and furnace injection and pipeline injection (NaHCO3) processes. Especially widely used in small power plants and industrial boilers. The process has low investment and good desulfurization effect. When ca/s=1.4~2.2, the desulfurization rate can reach 70%, and the denitration rate can reach 10%~20%. The molten sodium oxide decomposed by alkali is highly corrosive, and the volatilization of sodium oxide pollutes the environment. The slag produced by soda ash desulfurization has good fluidity and is difficult to remove. The price of soda water is also relatively high. Therefore, it is very rare to use soda ash as desulfurizer.
使用鈉基脫硫劑存在的問題是脫硫劑來源困難;脫硫產(chǎn)品中的鈉鹽易溶于水,對灰場水體造成污染;在干噴過程中,鈉基脫硫劑將no轉(zhuǎn)化為No3,導致排煙顏色變黃,影響電廠形象。
The problem of using sodium based desulfurizer is that the source of desulfurizer is difficult; The sodium salt in the desulfurization product is easily soluble in water, causing pollution to the water body of the ash yard; In the process of dry injection, sodium based desulfurizer converts no into No3, which causes the color of smoke to turn yellow and affects the image of the power plant.
脫硫催化劑
Desulfurization catalyst
3、氨基脫硫劑
3. Amino desulfurizer
在電子束輻照脫硫工藝和氨洗工藝中,氨通常以氨水或氨水的形式用作脫硫劑。氨基脫硫劑的活性很好,所以用量比其他脫硫劑少。氨基脫硫劑脫硫過程的副產(chǎn)物是硫酸銨,可用作農(nóng)業(yè)肥料。當氨用作脫硫劑時,應(yīng)注意氨的高價;無需準備,但需要特殊的運輸、儲存、計量和輸送設(shè)備;氨泄漏會引起異味、中毒等環(huán)境問題;過量的氨注入可能會形成白煙排放
In electron beam irradiation desulfurization process and ammonia washing process, ammonia is usually used as desulfurizer in the form of ammonia water or ammonia water. Amino desulfurizer has good activity, so its dosage is less than other desulfurizers. Ammonium sulfate is the by-product of the desulfurization process of amino desulfurizer, which can be used as agricultural fertilizer. When ammonia is used as desulfurizer, attention should be paid to the high price of ammonia; No preparation is required, but special transportation, storage, metering and conveying equipment are required; Ammonia leakage will cause environmental problems such as odor and poisoning; Excessive ammonia injection may cause white smoke emission
4、鎂基脫硫劑
4. Mg-based desulfurizer
鎂基脫硫基團包括MgO、Mg(OH)2等。氧化鎂(輕燒氧化鎂)和氫氧化鎂因其緩沖性能強(pH值高達9)、活性和吸附能力強、使用可靠、無腐蝕性,在環(huán)境領(lǐng)域得到廣泛應(yīng)用。1350℃下鎂與硫的反應(yīng)平衡常數(shù)不如電石和石灰脫硫的平衡常數(shù)高。然而,鎂和硫具有很高的親和力,反應(yīng)區(qū)的動力學條件非常好。反應(yīng)迅速且非常強烈。鎂與硫在鐵水中反應(yīng)生成的MGS熔點高(2000℃),密度低(2.82g/cm3),易結(jié)渣。然而,鎂具有很高的活性,因此必須將其作為脫硫劑進行鈍化。
Mg-based desulfurization groups include MgO, Mg (OH) 2, etc. Magnesium oxide (light burned magnesium oxide) and magnesium hydroxide are widely used in the environmental field because of their strong buffering performance (pH value up to 9), strong activity and adsorption capacity, safe and reliable use, and non-corrosive. The reaction equilibrium constant of magnesium and sulfur at 1350 ℃ is not as high as that of calcium carbide and lime desulfurization. However, magnesium and sulfur have a high affinity, and the kinetic conditions in the reaction zone are very good. The reaction is rapid and very strong. The MGS produced by the reaction of magnesium and sulfur in molten iron has high melting point (2000 ℃), low density (2.82g/cm3) and is easy to slag. However, magnesium has high activity, so it must be passivated as desulfurizer.
鎂不僅可以用單一脫硫劑脫硫,還可以用鎂基復合脫硫劑脫硫。鎂基脫硫劑中使用的鎂粉也需要鈍化處理。該鎂粉采用銑刀切割或噴涂方法制成,直徑0.15~1.2mm,w(mg)=90%,其余為鈍化層。流動性處理過的氧化鈣粉末與鎂粉混合,以確保密相輸送順暢。鎂石灰復合脫硫劑的脫硫反應(yīng)機理如下:由于添加了石灰,氧化鈣粉包裹和分散了鎂粉,使其均勻分布在鐵水中,不僅擴大了反應(yīng)面積,而且減緩了鎂的氣化速度,提高了鎂的利用率;Cao可以作為絡(luò)合物的核心來進行μm)聚合,可以加速夾雜物的上浮,不斷降低反射區(qū)的硫濃度,提高脫硫速度,有利于快速深度脫硫的要求。
Magnesium can be desulfurized not only with a single desulfurizer, but also with magnesium-based composite desulfurizer. The magnesium powder used in magnesium-based desulfurizer also needs passivation treatment. The magnesium powder is made by milling cutter cutting or spraying, with a diameter of 0.15~1.2mm, w (mg)=90%, and the rest is the passivation layer. The fluidity treated calcium oxide powder is mixed with magnesium powder to ensure smooth transportation of the phase. The desulfurization reaction mechanism of magnesium-lime composite desulfurizer is as follows: due to the addition of lime, calcium oxide powder wraps and disperses magnesium powder, making it evenly distributed in molten iron, which not only expands the reaction area, but also slows down the gasification rate of magnesium and improves the utilization rate of magnesium; Cao can be used as the core of complex μ m) Polymerization can accelerate the floating of inclusions, continuously reduce the sulfur concentration in the reflection zone, and improve the desulfurization speed, which is conducive to the requirements of rapid and deep desulfurization.
鎂脫硫具有技術(shù)、經(jīng)濟合理、維護檢修方便、連續(xù)運行可靠、無石膏結(jié)垢、副產(chǎn)硫酸鎂或回收利用、無污染排放等優(yōu)點。由于鎂脫硫劑在技術(shù)和經(jīng)濟上的優(yōu)勢以及研究開發(fā)的深入,鎂脫硫劑的應(yīng)用越來越廣泛。
Magnesium desulfurization has the advantages of advanced technology, reasonable economy, convenient maintenance and repair, safe and reliable continuous operation, no gypsum scaling, by-product magnesium sulfate or recycling, no pollution discharge, etc. Due to the technical and economic advantages of magnesium desulfurizer and the in-depth research and development, the application of magnesium desulfurizer is more and more extensive.
5、工業(yè)廢物作為脫硫劑
5. Industrial waste as desulfurizer
主要有兩種廢物可以起到脫硫作用。一種是電石渣、白泥、石灰渣等鈣基工業(yè)廢物,另一種是堿土工業(yè)廢物,如鋼渣、冶金廢物、化學廢物等,對脫硫有一定的催化作用。1000~1100℃時,白泥和電石渣的固硫率較高,1000℃時,白泥的固硫率高達84.5%,甚高于Cao。然而,當溫度上升到1200~1300℃時,白泥和電石渣的固硫率迅速下降,即白泥和電石渣在低溫下具有較高的固硫效果。
There are mainly two kinds of wastes that can play a role in desulfurization. One is calcium-based industrial waste such as calcium carbide slag, white mud and lime slag, and the other is alkaline earth industrial waste, such as steel slag, metallurgical waste and chemical waste, which has a certain catalytic effect on desulfurization. At 1000~1100 ℃, the sulfur fixation rate of white mud and carbide slag is higher, and at 1000 ℃, the sulfur fixation rate of white mud is as high as 84.5%, even higher than that of CaO. However, when the temperature rises to 1200~1300 ℃, the sulfur fixation rate of white mud and carbide slag decreases rapidly, that is, white mud and carbide slag have high sulfur fixation effect at low temperature.
The above is a detailed introduction about wet desulfurization, which I hope will help you. If you have any questions, please contact us. We will provide you with our service http://www.mimi5.cn