氨法脱硫中亚硫酸铵的氧化工艺参数

Process parameters of ammonium sulfite oxidation in ammonia desulfurization technology

通过改变亚硫酸铵初始浓度、硫酸铵初始浓度、反应温度、混合液p H值、空气流量、催化剂浓度,研究氨法脱硫中亚硫酸铵氧化率的变化.结果表明:(NH4)2SO3的浓度与(NH4)2SO3的氧化率成反比关系;初始(NH4)2SO4浓度越大,(NH4)2SO3氧化率越低;当反应温度为40～60?C时,随着温度的升高,(NH4)2SO3的氧化率不断增大;(NH4)2SO3氧化率受混合液p H值的影响,较合适的p H值为5.5;当空气流量为100～400 L/h时,随着空气流量的增大,(NH4)2SO3的氧化率增大;随着催化剂Co SO4浓度升高,(NH4)2SO3氧化率增大.结合氨法脱硫工程实例考虑,当反应温度控制在50?C左右,(NH4)2SO3采用低浓度氧化,混合液p H值为5.5,空气流量为300 L/h,催化剂浓度较高时,(NH4)2SO3的氧化率较高.

The influence of affecting factors on the oxidation rate of（NH4）2SO3 including concentration of（NH4）2SO3, concentration of（NH4）2SO4, temperature, p H value, air flow rate and concentration of Co SO4 were studied. The results showed that the oxidation rate of（NH4）2SO3 is lowered with the increase of initial concentration of（NH4）2SO3. It is the same as concentration of（NH4）2SO4. From 40？C to 60？C,（NH4）2SO3 oxidation rate increases with the increase of reaction temperature. The（NH4）2SO3 oxidation rate is also influenced by the p H value of the mixed solution, with the most preferred value being 5.5. When the air flow rate is within 100-400 L/h and with increase of air flow,（NH4）2SO3 oxidation rate increases. Taking into account the ammonia desulfurization project, the most appropriate process parameters are： reaction temperature at about50？C,（NH4）2SO3 at low concentration, the p H value of mixed solution at 5.5, air flow rate at 300 L/h and Co SO4 at high concentration.