tailieunhanh - REMEDIATION OF PETROLEUM CONTAMINATED SOILS - SECTION 6

Các hợp chất hữu cơ dễ bay hơi trong dầu khí Sản phẩm 6,1 phát thải từ NHIỄM ĐẤT Quản lý chất thải nguy hại liên quan đến hoạt động nhiều có thể dẫn đến khí thải (Allen và Blaney, 1985). Ví dụ, xử lý chất thải tại bãi chôn lấp có thể giải phóng các chất hữu cơ dễ bay hơi (VOC). Chuyển giao chất thải và xử lý các hoạt động cũng có thể là một nguồn đáng kể phát thải VOC. Phát thải từ lưu trữ độc hại xử lý chất thải và các cơ sở xử lý (TSDFs). | Section 6 Volatile Organic Compounds in Petroleum Products EMISSIONS PRODUCED FROM SOIL CONTAMINATION Management of hazardous wastes involves many operations that can result in air emissions Allen and Blaney 1985 . For example disposal of wastes in landfills may release volatile organic compounds VOCs . Waste transfer and handling operations may also be a significant source of VOC emissions. Emissions from hazardous waste treatment storage and disposal facilities TSDFs have been estimated to be in excess of Mt year and possibly over 5 Mt year Breton et al. 1983 . It has been reported that at least one third of the total emissions of over 50 volatile hazardous chemicals are from TSDFs Springer Valsaraj and Thibodeaux 1986 . VOC emissions from industry transportation and other sources have been estimated to be and Mt year respectively Breton et al. 1983 . Table gives the estimated relative emissions from various types of TSDFs. Landfarming can be used if volatilization of VOCs into the air is permitted however there is growing concern over VOC emissions and resulting air pollution IT Corporation 1987 . Emissions from landtreatment facilities arise by volatilization from the wastes that have been spread on the soil prior to being incorporated within the top layers Ehrenfeld Ong Farino Spawn Jasinski Murphy Dixon and Rissmann 1986 . They later arise after the wastes have been mixed into the soil as the materials volatilize and diffuse upward through the soil. The process of spreading and tilling of the contaminated soil results in volatilization of a significant fraction up to 40 to 60 of the volatile organics. By using the emission isolation flex chamber method to measure VOC emission rates it was found that tilling caused a two- to tenfold increase in the emission rates with peak emissions occurring within the first 4 h after tilling Blaney Eklund Thorneloe and Wetherold 1986 . Results from a landtreatment facility demonstrated that more than