College of Power and Energy Engineering, Harbin Engineering University, Harbin, 150001, China.
College of Power and Energy Engineering, Harbin Engineering University, Harbin, 150001, China.
J Hazard Mater. 2020 Nov 15;399:123069. doi: 10.1016/j.jhazmat.2020.123069. Epub 2020 May 30.
The novel combined system using NaSO/urea was used to simultaneously absorb nitric oxide and sulfur dioxide emissions from marine diesel engines as well as inhibit the formation of nitrate in cleaning wastewater to meet the increasingly stringent requirements of regulations. The influences of reaction temperature, NaSO concentration, urea concentration, SO concentration, NO concentration and pH value on SO removal efficiency, NO removal efficiency and nitrate concentration were investigated. The experimental results showed that different reaction temperatures had different influences on SO removal efficiency, NO removal efficiency and nitrate concentration. An increase in NaSO could improve the absorption of NO. The addition of urea could effectively improve the removal efficiency of NO and reduce the nitrate concentration. The removal efficiencies of 1000 ppm NO and 1000 ppm SO achieved 100 % with 0.2 mol/L NaSO and 2 mol/L urea at 70℃, and the nitrate content was 8.56 mg/L which was far lower than the regulatory requirement of 60 mg/L. The acidic condition (pH ≤ 5.5) not only facilitated the absorption of NO but also reduced the generation of nitrate. According to the experimental results, the novel combined system was promising to be applied to the control technology of marine diesel engine exhaust.
该新型联合系统采用 NaSO/urea 同时吸收船用柴油机的氮氧化物和二氧化硫排放物，并抑制清洁废水中硝酸盐的形成，以满足日益严格的法规要求。考察了反应温度、NaSO 浓度、尿素浓度、SO 浓度、NO 浓度和 pH 值对 SO 去除效率、NO 去除效率和硝酸盐浓度的影响。实验结果表明，不同的反应温度对 SO 去除效率、NO 去除效率和硝酸盐浓度有不同的影响。增加 NaSO 可以提高 NO 的吸收。添加尿素可以有效提高 NO 的去除效率并降低硝酸盐浓度。在 70℃下，当 NaSO 浓度为 0.2mol/L，尿素浓度为 2mol/L 时，1000ppm 的 NO 和 1000ppm 的 SO 的去除效率达到 100%，硝酸盐含量为 8.56mg/L，远低于 60mg/L 的规定要求。酸性条件（pH≤5.5）不仅有利于 NO 的吸收，而且减少了硝酸盐的生成。根据实验结果，该新型联合系统有望应用于船用柴油机排气的控制技术。
