催化裂解装置烟气除尘水处理系统运行分析
|
摘要
催化裂解再生烟气中含有大量的SO_x,NO_x和颗粒物,会对所在区域环境造成较为严重的污染。随着目前环保形势日益严峻,国家对废气、废水排放指标提出更加严格的要求,设置脱硝除尘系统成为必然。大榭石化2.2 Mt/a催化裂解装置烟气除尘水处理系统于2016年6月与主体装置同步开工以来,一直运行良好。烟气除尘系统采用湿法除尘脱硫技术,烟气经净化处理后,烟气粉尘质量浓度可降至20 mg/m~3,SO_x质量浓度降至10 mg/m~3。外排污水经水处理系统沉淀氧化后,悬浮物质量浓度为22 mg/L,化学需氧量COD为20 mg/L,pH值控制在6～9,均能满足环保要求。系统运行过程中,出现了洗涤塔除沫网被腐蚀、外排含盐污水COD异常偏高、氧化罐结垢和出口含盐污水pH值偏高等问题,通过对存在问题进行分析和总结,采取了有效解决措施,保证了装置平稳运行。
The regenerated flue gas from catalytic unit cracking contains a large amount of SO_x, NO_x and particulate matter, which will cause serious pollution to the environment in the region. With the increasingly serious environmental protection situation, the state has put forward stricter requirements for the emission index of waste gas and wastewater, and it is necessary to set up a denitrification and dust removal system. The water treatment system of flue gas dust removal of 2.2 MM TPY catalytic cracking unit in CNOOC Ningbo Daxie Petrochemical Co. has been running well since it was started synchronously with the main device in June 2016. The wet dedusting and desulphurization technology is adopted by flue gas dust removal system. After purification, the mass concentration of flue gas dust can be reduced to 20 mg/m~3 and the mass concentration of SO_x can be reduced to 10 mg/m~3. After sedimentation and oxidation in water treatment system, the concentration of suspended substance is 22 mg/L, COD is 20 mg/L and pH value is 6～9, which can meet the environmental protection requirements.During the operation of the system, problems such as corrosion of the foam removal network of the scrubbing tower, exceptionally high COD in effluent of saline sewage, scaling of the oxidation tank and high pH value of the saline sewage from the outlet arise. Based on the analysis and summary of the existing problems, effective measures are taken to ensure smooth running of the unit.
The regenerated flue gas from catalytic unit cracking contains a large amount of SO_x, NO_x and particulate matter, which will cause serious pollution to the environment in the region. With the increasingly serious environmental protection situation, the state has put forward stricter requirements for the emission index of waste gas and wastewater, and it is necessary to set up a denitrification and dust removal system. The water treatment system of flue gas dust removal of 2.2 MM TPY catalytic cracking unit in CNOOC Ningbo Daxie Petrochemical Co. has been running well since it was started synchronously with the main device in June 2016. The wet dedusting and desulphurization technology is adopted by flue gas dust removal system. After purification, the mass concentration of flue gas dust can be reduced to 20 mg/m~3 and the mass concentration of SO_x can be reduced to 10 mg/m~3. After sedimentation and oxidation in water treatment system, the concentration of suspended substance is 22 mg/L, COD is 20 mg/L and pH value is 6～9, which can meet the environmental protection requirements.During the operation of the system, problems such as corrosion of the foam removal network of the scrubbing tower, exceptionally high COD in effluent of saline sewage, scaling of the oxidation tank and high pH value of the saline sewage from the outlet arise. Based on the analysis and summary of the existing problems, effective measures are taken to ensure smooth running of the unit.
引文
[1] 赵长斌.增强型催化裂解装置开工初期调整策略及效果[J].石油炼制与化工,2017,48(9):54.
[2] 张执刚,谢朝刚,朱根权.增强型催化裂解技术(DCC-PLUS)试验研究[J].石油炼制与化工,2010,41(6):39.
[3] 薛建明,王小明,刘建民,等.湿法烟气脱硫设计及设备选型手册[M].北京:中国电力出版社,2011:10.
[4] 王雪峰,马胜平.催化烟气脱硫装置运行效果分析[J].建筑工程技术与设计,2014(30):845.
[5] 武春锦,吕武华,梅毅,等.湿法烟气脱硫技术及运行经济性分析[J].化工进展,2015,34(12):4370.
[6] 李永林.中国石化2016年催化裂化交流会论文集[C].北京:中国石化出版社,2016:534.
[2] 张执刚,谢朝刚,朱根权.增强型催化裂解技术(DCC-PLUS)试验研究[J].石油炼制与化工,2010,41(6):39.
[3] 薛建明,王小明,刘建民,等.湿法烟气脱硫设计及设备选型手册[M].北京:中国电力出版社,2011:10.
[4] 王雪峰,马胜平.催化烟气脱硫装置运行效果分析[J].建筑工程技术与设计,2014(30):845.
[5] 武春锦,吕武华,梅毅,等.湿法烟气脱硫技术及运行经济性分析[J].化工进展,2015,34(12):4370.
[6] 李永林.中国石化2016年催化裂化交流会论文集[C].北京:中国石化出版社,2016:534.