气田高含硫污水负压气提脱硫及尾气无害化处理技术研究

针对目前普光气田高含硫污水气提脱硫率低的问题,通过采用“曝气+负压气提+尾气催化氧化”工艺技术,设计正交实验,优选出最优负压气提脱硫操作条件为:污水pH值4.0、温度20℃、气提真空度-0.02 MPa、空气曝气气液体积比20∶1,污水负压气提脱硫率高达94%。各操作条件对脱硫率的影响由强到弱顺序为:空气曝气气液比、污水pH值、气提真空度和污水温度。实验优选出铁基离子液体作为尾气脱硫催化剂。结果表明,铁基离子液体中Fe 3+对H 2S氧化速率很快,净化后尾气中H 2S质量浓度为0 mg/m^3,氧化产物为单质S,同时离子液体可通过空气将Fe 2+氧化成Fe 3+,实现低成本循环利用,解决了含硫尾气燃烧的SO 2排放问题。

Research on the technology of vacuum extraction desulfurization and harmless treatment of gas field high-sulfur wastewater

Aiming at the low desulfurization rate of high-sulfur wastewater in Puguang gas field,the technology of“aeration+vacuum extraction+catalytic oxidation of tail gas”was adopted and orthogonal experiment optimization was designed.The optimized operating conditions are shown as follows:sewage pH value of 4.0,temperature of 20℃,gas stripping vacuum degree of-0.02 MPa,aeration gas-liquid ratio of 20∶1,and sewage desulfurization ratio is as high as 94%.The influence of vacuum desulfurization operation conditions on the desulfurization rate from strong to weak in the order is air aeration gas-liquid ratio,sewage pH value,gas extraction vacuum degree and sewage temperature.Iron-base ionic liquids was optimized as exhaust gas desulfurization catalyst in the test.The results show that Fe 3+oxidized H 2S at a very fast rate in iron-based ionic liquids,the concentration of H 2S in tail gas is 0 mg/m^3,and the oxidation products is elemental sulfur.Meanwhile,Fe 2+in ionic liquids can be oxidized to Fe 3+by air.The application of iron-based ionic liquids not only realizes the low cost reuse of the desulfurization liquid,but also completely eliminates the SO 2 emission problem caused by the combustion of the tail gas containing sulfur.