ELIMINATION OF PCBS BY SUPERCRITICAL EXTRACTION AND WET OXIDATION

拟议研究工作的具体目标是评估 超临界萃取（SCE）技术可行性和超临界 湿法氧化（SCWO）工艺以去除和破坏卤代芳族化合物 废物填埋场的碳氢化合物。 超临界流体的优点 与传统的废物处理方法相比， 有机物在超临界条件下的溶解度， 有机物（在超临界水氧化的情况下），污染物分离的简单性， 溶剂流，并降低加工中的能量成本。 此外，本发明还 经过处理的土壤不会被任何有毒溶剂污染， 处理. 在第一个供资期间的努力将导致 超临界萃取的设计、施工和调试， 超临界水氧化实验室装置。 前者在20 o 在100 ℃至100 ℃和50 atm至500 atm下，以及后者在100 ℃至100 atm下， 500摄氏度和50大气压至600大气压。 该设施具有广泛的能力 对于这种允许获得热动力学的研究活动， 解吸速率，和动力学数据在这些条件下，在一个安全的， 卫生的环境。 热力学模型关联溶解度数据， 筛选测试，以识别CO2/改性剂（甲醇、丙烷、甲苯） 使用2，4，5/2 '，4'，5 '-六氯联苯/合成土壤样本的系统，以及 选定的超临界水氧化初步可行性实验将已完成。 拟议的研究集中于三个具体目标。 (1)平衡和 将使用以下方法获得Aroclor 1248 SCE的解吸速率数据： 合成土壤样品和实际多氯联苯污染样品。 分析 数据将确定工艺可行性并允许初步设计。 （二） 将进行动力学实验，以获得以下的超临界水氧化速率数据： 2，4，5/2 '，4'，5 '-六氯联苯和污染物的提取液 土壤 数据分析将确定工艺的可行性和许可证 工艺设计估算。 (3)实验室规模的单元实验将 执行与合成和实际土壤样品，以评估和改善 技术. 将对移动的装置进行经济分析， 现场治疗。

The specific objectives of the proposed research work are to assess the technical feasibility of supercritical extraction (SCE) and supercritical wet oxidation (SCWO) processes to remove and destroy halogenated aromatic hydrocarbons from waste landfill sites. The advantages of supercritical processes over conventional waste treatment methods include enhanced solubility of organics at supercritical conditions, complete oxidation of organics (in the case of SCWO), simplicity of separation of pollutants from the solvent stream, and reduced energy costs in the processing. Further, the treated soil will not be contaminated with any toxic solvent after processing. The effort during the first funding period will have resulted in the design, construction and commission of supercritical extraction and supercritical water oxidation laboratory units. The former operates at 20o to 100 degrees C and 50 atm to 500 atm, and the latter at 100 degrees C to 500 degrees C and 50 atm to 600 atm. This facility has broad capabilities for this research activity permitting acquisition of thermo-dynamic, desorption rate, and kinetic data at these conditions in a safe and hygienic environment. Thermodynamic models to correlate solubility data, screening tests to identify CO2/modifier (methanol, propane, toluene) systems with 2,4,5/2',4',5'-hexachlorobiphenyl/synthetic soil samples, and selected SCWO preliminary feasibility experiments will have been completed. The proposed research focuses on three specific aims. (1) Equilibrium and desorption rate data will be obtained for SCE of Aroclor 1248 using synthetic soil samples and actual PCB contaminated samples. Analysis of data will determine process feasibility and permit preliminary design. (2) Kinetic experiments will be conducted to obtain SCWO rate data of 2,4,5/2',4',5'-hexachlorobiphenyl and extraction liquids from contaminates soils. Data analysis will determine the process feasibility and permit process design estimations. (3) Bench-scale unit experiments will be executed with synthetic and actual soil samples to evaluate and improve the technology. An economic analysis will be conducted for a mobile unit for on-site treatment.