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）和超临界的技术可行性 湿式氧化 (SCWO) 工艺可去除和破坏卤代芳香族化合物 来自垃圾填埋场的碳氢化合物。 超临界的优点 与传统废物处理方法相比，流程包括增强 有机物在超临界条件下的溶解度，完全氧化 有机物（在 SCWO 的情况下），污染物分离简单 溶剂流，并降低加工过程中的能源成本。 此外， 处理后的土壤不会受到任何有毒溶剂的污染 处理。 第一个资助期间的努力将导致 超临界萃取和超临界萃取的设计、施工和调试 超临界水氧化实验室装置。 前者工作温度为20o 至 100 摄氏度和 50 个大气压至 500 个大气压，后者在 100 摄氏度至 500 摄氏度和 50 个大气压至 600 个大气压。 该设施具有广泛的功能 对于这项研究活动，允许获取热力学， 解吸速率和这些条件下的动力学数据在安全和 卫生环境。 关联溶解度数据的热力学模型， 筛选测试以确定 CO2/改性剂（甲醇、丙烷、甲苯） 具有 2,4,5/2',4',5'-六氯联苯/合成土壤样品的系统，以及 选定的SCWO初步可行性实验将已经完成。 拟议的研究重点关注三个具体目标。 (1) 平衡和 Aroclor 1248 的 SCE 解吸速率数据将使用以下方法获得 合成土壤样品和实际 PCB 污染样品。 分析 数据将确定工艺可行性并允许初步设计。 (2) 将进行动力学实验以获得 SCWO 速率数据 2,4,5/2',4',5'-六氯联苯及污染物提取液 土壤。 数据分析将确定流程的可行性和许可 流程设计估算。 （3）小规模单元实验 使用合成和实际土壤样本进行评估和改进 技术。 将对移动装置进行经济分析 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.