碱液脱硫在天然气净化厂的应用

Application of alkali desulfurization in natural gas purification plant

目的针对天然气净化厂硫磺回收尾气处理装置的运行特点及现有工艺的优缺点,提出一种能够适应中小规模、工况变化大的尾气处理工艺。方法采用碱液脱硫工艺应用于天然气净化厂硫磺回收尾气处理,采取了尾气NaOH碱洗“洗涤塔+脱硫塔”双塔组合脱硫、优化焚烧炉结构、提升硫酸钠产品指标等措施。结果碱液脱硫后,排放尾气中SO_(2)质量浓度为10~268 mg/m^(3),满足GB 39728-2020《陆上石油天然气开采工业污染物排放标准》的要求,且副产物硫酸钠满足合格品要求直接外销。结论碱洗脱硫可满足天然气净化厂尾气处理装置技术、经济性的要求,同时取得了巨大的环保效益,可为同类装置提供技术参考。

Objective Aiming at the operation characteristics of sulfur recovery tail gas treatment unit in natural gas purification plant and the advantages and disadvantages of the existing process,an tail gas treatment process that can adapt to small and medium-sized and large changes in working conditions is proposed.Methods The alkali liquor desulfurization process was applied to the sulfur recovery tail gas treatment in the natural gas purification plant,and measures such as tail gas NaOH alkali washing"scrubber+desulfurization tower"double tower combined desulfurization,the optimization of incinerator structure,and improvement of sodium sulfate product index were taken.Results The SO_(2) mass concentration in tail gas was 10-268 mg/m^(3) after alkali liquor desulfurization,which met the requirements of GB 39728-2020 Emission standard of air pollutants for onshore oil and gas exploitation and production industry,and the by-product sodium sulfate met the requirements of qualified products and was directly exported.Conclusions Alkali washing desulfurization can meet the technical and economic requirements of tail gas treatment unit in natural gas purification plant,and has achieved great environmental benefits,which can provide technical reference for similar units.