tailieunhanh - Practical Design Calculations for Groundwater and Soil Remediation - Chapter 7

VOC-đầy không khí điều trị Xử lý ô nhiễm đất và nước ngầm bị ô nhiễm thường là kết quả trong việc chuyển các chất gây ô nhiễm hữu cơ vào giai đoạn không khí. Phát triển và thực hiện của một chiến lược kiểm soát khí thải không phải là một phần không thể thiếu của các chương trình khắc phục hậu quả tổng thể. Không khí kiểm soát khí thải có thể ảnh hưởng đến costeffectiveness của một giải pháp thay thế khắc phục hậu quả cụ thể. Các nguồn phổ biến của VOC-đầy khí từ các hoạt động. | Kuo Jeff VOC-laden air treatment Practical Design Calculations for Groundwater and Soil Remedition Boca Raton CRC Press LLC 1999 chapter seven VOC-laden air treatment Remediation of contaminated soil and groundwater often results in transferring organic contaminants into the air phase. Development and implementation of an air emission control strategy should be an integral part of the overall remediation program. Air emission control may affect the costeffectiveness of a specific remedial alternative. Common sources of VOC-laden off-gas from soil groundwater remediation activities include soil vapor extraction air sparging air stripping solidification stabilization and bioremediation. This chapter illustrates the design calculations for commonly used treatment technologies activated carbon adsorption direct incineration catalytic incineration IC engines and biofiltration. Activated carbon adsorption Process description Activated carbon adsorption is one of the most commonly used air pollution control processes for reducing VOC emission from soil groundwater remediation. The process is very effective in removing a wide range of VOCs. The most common form of activated carbon for this type of application is granular activated carbon GAC . Activated carbon has a fixed capacity or a limited number of active adsorption sites. Once the adsorbing contaminants occupy most of the available sites the adsorption efficiency will drop significantly. If the operation is continued beyond this point the breakthrough point will be reached and the effluent concentration will increase sharply. Eventually carbon would be saturated exhausted or spent when all sites are occupied. The spent carbon needs to be regenerated or disposed of. Two pretreatment processes are often required to optimize the performance of GAC systems. The first is cooling and the other is dehumidifica 1999 CRC Press LLC tion. Adsorption of VOCs is generally exothermic which is favored by lower temperatures. .