Na_2S_2O_8/NaClO_2复合吸收液工业脱硝新方法

A NEW METHOD FOR DENITRATION ADSORPTION BY Na_2S_2O_8/NaClO_2 COMPOUND ABSORBENT IN INDUSTRY

针对氮氧化物排放标准日益严格而现有脱硝技术不能满足要求的现状,提出了Na_2S_2O_8/NaClO_2复合吸收液脱硝的新方法。在小型鼓泡反应器中进行脱硝实验,讨论了Na_2S_2O_8和NaClO_2浓度、反应温度、溶液pH、NO浓度等因素对NO脱除效率的影响,在此基础上分析了复合吸收液的脱硝机理。通过比较复合吸收液与单一吸收液的脱硝效果和成本,探究其在脱硝方面的工业应用前景。实验结果表明:当吸收液初始pH为5,Na_2S_2O_8浓度为0.05 mol/L,NaClO_2浓度为0.0025 mol/L,反应温度为50℃时,NO脱硝率可达95%;复合吸收液ClO^-_2、ClO_2、S_2O^(2-)_8共同参与NO的脱硝反应,中间产物ClO_2担负了重要氧化吸收作用,显著地提高了脱硝效率;Na_2S_2O_8/NaClO_2复合吸收液比单一吸收液脱硝成本低、效率高,工业应用前景良好。

Aiming at the status quo that NOx emission controlling standards are increasingly strict and existing denitration technologies cannot meet requirements, a new method for denitration by Na2S2O8/NaClO2 compound absorbent was proposed. The denitration experiment was carried out in a small bubble reactor, and the effects of Na2S2O8 and NaClO2 concentrations, reaction temperatures, the solution pH and NO concentration on the NO removal efficiency were discussed, and based on which the denitration mechanism of the compound absorbent was analyzed. By comparing the denitration effect and cost between the compound absorbent and the single absorbent, its industrial application prospect in denitration was explored. The results indicated that: for the absorbent, when the initial pH was 5, the concentrations of Na2S2O8 and NaClO2 were 0.05 mol/L and 0.0025 mol/L respectively, and the reaction temperature was 50 ℃, the NO removal efficiency could be up to 95%;the ClO-2, ClO2, and S2O2-8 compound absorbents co-participated in removal reaction of NO, and the intermediate product ClO2 played an important role of oxidation adsorption and improved the denitration efficiency significantly;the new method of the Na2S2O8/NaClO2 compound absorbent had a striking industrial application due to its lower cost and higher efficiency than that of the single adsorption absorbent method.