天然气净化厂Cansolv尾气处理装置运行问题及优化

随着天然气净化厂Cansolv尾气处理装置的陆续投产运行,装置整体运行平稳,均能实现较低浓度的SO₂排放,但在运行过程中,存在胺液中热稳定盐含量偏高、中和废水中COD及还原性硫含量过高、烟气加热器窜漏等问题。通过对存在的问题进行分析,采取了以下措施:①加强尾气焚烧炉配风操作和炉膛温度控制；②增加湿式电除雾器电晕极和沉淀极的冲洗频率；③对湿式电除雾器绝缘子室接入氮气进行气封保护；④增大胺液净化装置程序中用除盐水置换DS溶液的水量；⑤调整DS溶液温度和尾气进口温度；⑥控制DS溶液质量分数；⑦增加臭氧催化氧化工艺；⑧对烟气加热器入口管线进行伴热；⑨烟气加热前设置排液口；⑩升级烟气加热器材质；○11优化设备布置等。通过采取上述措施,有效保证了Cansolv尾气处理装置的安全平稳运行,尾气中SO₂排放质量浓度满足GB 39728-2020《陆上石油天然气开采工业污染物排放标准》的要求。 

Operation problems and optimization of Cansolv tail gas treatment device in natural gas purification plant

With the commissioning of Cansolv tail gas treatment device in natural gas purification plant, the devices operate smoothly overall, the SO₂ mass concentration in tail gas can achieve low emissions. But in the course of operation, there existed a series of problems as follows:the thermal stability salt content in amine solution was high, the COD and reductive S content in neutralizing wastewater was too high, and the flue gas heater leaked. By analyzing the existing problems, the following measures had been taken:(1) Enhancing the wind distribution operation and furnace temperature control of the exhaust incinerator; (2) Increasing the flushing frequency of corona and precipitation electrode of the wet electrostatic precipitator; (3) Introducing nitrogen gas into the insulator chamber of wet electrostatic precipitator for gas seal protection; (4) Increasing the flow rate of desalinated water to replace the DS solution in the program of amine solution purification device; (5) Adjusting the temperature of the DS solution and the inlet temperature of the exhaust gas; (6) Controlling the mass fraction of the DS solution; (7) Adding the process of ozone catalytic oxidation; (8) Increasing heat tracing pipeline of the flue gas heater inlet pipeline; (9) Setting the discharge port before the flue gas being heated; (10) Upgrading the material of flue gas heater; (11) Optimizing the equipment arrangement. By taking above measures, the safe and smooth operation of Cansolv tail gas treatment unit was ensured effectively, and the SO₂ mass concentration in emission tail gas meets the requirements of GB 39728-2020 Emission Standard of Air Pollutants for Onshore Oil and Gas Exploitation and Production Industry.