水合肼副产盐渣用于生产离子膜法烧碱

Recycling by-product salt slag from production of hydrazine hydrate to produce ion-exchange membrane caustic soda

通过氧化水合肼装置副产盐渣中的氮化物,研究了不同的氧化剂、盐水中碱含量、通氯量、反应温度、终点pH值对处理后盐水质量的影响。中试结果表明:饱和未处理盐水中碱(折碳酸钠)含量为氮含量的10倍、反应温度为40～45℃时,通氯量为氮含量的12倍,终点盐水的pH值为7～8,可将饱和未处理盐水中氮质量浓度(有机氮化物和无机氮化物)由450.0 mg/L降至小于1.0 mg/L。某公司将处理后的饱和盐水用于生产离子膜法烧碱,跟踪查定结果表明:离子膜电解槽运行良好,不仅可创造一定的经济效益,还解决了水合肼生产中的环境污染问题。

The nitrogenous compounds contained in by-product salt slag from production of hydrazine hydrate were oxidized.The influences of different oxidants,basic content in brine,chlorine flow,reaction temperature,pH value at reaction endpoint on the quality of treated brine were studied.The pilot test results showed that the nitrogen content（including organic and inorganic nitrogenous compounds） in brine reduced from 450.0 mg/L to less than 1.0 mg/L when the untreated saturated brine contained basic content（based on sodium carbonate） 10 times nitrogen content and reaction temperature was 40-50 ℃,feeding amount of chlorine was 12 times nitrogen content and pH value of brine at reaction endpoint was 7-8.The treated saturated brine was used in the ion-exchange membrane electrolysis procedure in caustic soda plant of a company.The tracking examination results showed the ion-exchange membrane electrolyzers run well.Thus,not only could some benefits be created,but also the problem of environmental pollution in production of hydrazine hydrate could be solved.