Abstract: The oilfield has been in operation for more than 50 years （as of 2025）. Since the systematic upgrade and revamping carried out in 2016,its production capacity has achieved a significant leap,with crude oil output increasing from 10,880 tons before the revamp to 40,800 tons. Along with this sharp rise in production,the volume of associated gas has also increased markedly,resulting in frequent heavy black smoke emissions from the eastern and southern flares during combustion,which caused severe environmental pollution in surrounding areas. Based on the flare black smoke formation mechanism,this paper systematically analyzes the root causes of black smoke generation and confirms that the increased concentration of heavy components （especially C₃+ hydrocarbons） and the lowered hydrogen-to-carbon ratio in the flare gas are the key factors leading to incomplete combustion and black smoke formation. Combined with on-site process flows and equipment operating conditions,an in-depth analysis is conducted on the specific issues existing in the torch system in terms of equipment configuration,operation and maintenance,and process design. Accordingly,a series of comprehensive treatment measures are proposed,including optimizing flare knock-out drum operation,repairing the steam trap of the steam pipeline,adjusting the smoke-suppressing steam injection,introducing auxiliary combustion air,employing low-pressure compressors,and redistributing the liquid inflow from each gas station. Field practice demonstrates that the implementation of these integrated measures has significantly alleviated the black smoke issue,providing valuable reference for environmental optimization and efficient operation of flare systems in similar oilfields.

Key words: flare system, black smoke, incomplete combustion, heavy components, integrated mitigation, oilfield environmental protection