Separation of Fine Particles from Gas Streams by Condensational Growth

通过冷凝生长从气流中分离细颗粒

• 批准号: 9360161
• 负责人: Jinjun Sun
• 金额: $ 6.37万
• 依托单位: MSP Corporation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-04-15 至 1994-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9360161&HistoricalAwards=false
• 关键词: Separation; Fine; Particles; Gas; Streams

9360161 Sun A number of industrial processes, including incinerators and metallurgical processes, typically emit large numbers of fine particles. Measurements at an operating sewage sludge incinerator have shown that heavy metals (including Cadmium, Chromium, Nickel, Lead, and Zinc) are concentrated in the fine particle (approximately 0.25 mocrons) leaving the incinerators. Venturi scrubbers have been typically installed to remove particulate from these flue gas sources. The classical scrubbers are not capable of removing particles smaller than about 0.5 microns. The process proposed in this project is the use of the submicron particulate penetrating the Venturi scrubber as condensation nuclei for steam injected into the flue gas to supersaturate it with water vapor. Theoretical analyses show that water droplets as large as 1.0 micron can be produced with reasonable steam rates and contact times. These water droplets (a dilute suspension of the fine particulate) are removed from the flue gas stream with a high efficiency mist eliminator and drained to the scrubber sump. Preliminary analyses have shown that heavy metals in the fine particulate leaving the Venturi scrubber can be reduced by 90% using this process. With a relatively modest construction effort, the process proposed here can reduce fine particle and heavy metal emissions from incinerators equipped with wet scrubbers. The process is applicable to flue gas streams cleaned by wet scrubbers including incinerators, metallurgical processes, and coal-fired power plants with wet scrubbers for sulfur dioxide emission control. ***

9360161太阳：许多工业过程，包括焚烧炉和冶金过程，通常会排放大量的细颗粒。运行中的污水污泥焚烧炉的测量表明，重金属(包括镉、铬、镍、铅和锌)集中在离开焚烧炉的细颗粒物(约0.25微克)中。文丘里洗涤器通常被安装来去除这些烟气源中的颗粒。传统的洗涤器不能去除小于0.5微米的颗粒。该项目提出的工艺是使用穿透文丘里洗涤器的亚微米颗粒作为凝结核，将蒸汽注入烟气中，用水蒸气使其过饱和。理论分析表明，在合理的水蒸气流量和接触时间下，可以产生大到1.0微米的水滴。这些水滴(细小颗粒物的稀释悬浮液)用高效除雾器从烟道流中除去，然后排入洗涤器水池。初步分析表明，使用该工艺可以将文丘里洗涤器排出的细颗粒物中的重金属降低90%。通过相对温和的建设工作，这里提出的工艺可以减少配备湿式洗涤器的焚烧炉的细颗粒物和重金属排放。该工艺适用于包括焚烧炉、冶金过程在内的湿法洗涤器净化的烟气，以及具有控制二氧化硫排放的湿式洗涤器的燃煤电厂。***