炼厂环境控制技术新进展及趋势

Latest Technology Developments and Trends in Refinery Environmental Controls

炼厂产生的烟气含有大量的有害污染物,主要有一氧化碳、氮氧化物、硫氧化物和颗粒物等。发达国家和一些发展中国家对固定污染源污染物的允许排放量限制日益严格。违反排放标准的炼厂将依照国家规定受到严厉处罚。炼厂环境控制技术是一项价值达数十亿美元的经营业务。相关的技术提供商为数众多,分布于世界各地。控制硫氧化物、氮氧化物、颗粒物和挥发性有机化合物排放的主要技术大部分掌握在美国、西欧和日本的企业手中。环境控制通用技术主要有用于控制硫氧化物和颗粒物排放的烟气净化技术（再生器烟气洗涤器）、控制颗粒物的静电除尘器（ESP）系统、用于控制氮氧化物的选择性催化还原（SCR）和选择性非催化还原（SNCR）技术、用于控制氮氧化物的低/超低氮氧化物燃烧器、用于控制挥发性有机污染物的放空燃烧系统。炼厂催化裂化装置和硫磺装置专用的环境控制技术有借助添加剂降低催化裂化再生器的排放技术、降低硫磺装置硫氧化物和颗粒物排放的技术（改进的克劳斯工艺——富氧克劳斯工艺、亚露点克劳斯工艺、直接氧化克劳斯工艺）。炼厂应充分把握当前的污染防治和减排技术趋势及未来发展机会,根据技术的成本分析选择最佳技术,以最低的成本实现环保达标。

Flue gas from refineries is known to contain a large amount of pollutants（e.g.,CO,NOx,SOx,PM） that are considered harmful to the environment.Developed and some developing nations are imposing increas ingly stringent limits on the amount of these pollutants that are permitted to be discharged from stationary sources.Refiners violating emission standards will receive heavy fines.Environmental controls for refineries are a multi-billion dollar business with many players from different parts of the world.Most of the major technology holders in controlling emissions of SOx,PM,NOx,and VOCs are based in the US,Western Europe,and Japan.Major general environmental control technologies include flue gas scrubbing technologies for SOx and PM control（regenerator flue gas scrubbers）,electrostatic precipitators（ESPs） for PM control,selective catalytic（SCR） and non-catalytic（SNCR） reduction for NOx control,low and ultra-low NOx burners for NOx control,and flaring for VOCs control.Catalytic cracking units and sulfur units-specific environmental control technologies include technologies for reducing emissions from the FCC regenerator via additives,sulfur plant technologies for lowering SOx and PM emissions（modified Claus process-Claus process with oxygen enrichment,sub-dew point Claus process and direct oxidation Claus）.Refiners should capitalize on current trends and future opportunities offered by pollution control and emission reduction efforts to select the best available technology based on cost analysis to make sure that compliance with environmental rules is met while costs are minimized.