THERMAL REMEDIATION

我们将研究铬在简单的层流扩散火焰中的去向。 在项目的第一阶段。铬的氧化态 在火焰中形成的气溶胶将被确定为 火焰温度和停留时间。氯气对大气环境的影响 铬的命运将在这个不均匀的系统中得到检验。这个 排放的碳烟颗粒中可能含有铬 还将通过收集火焰上方的烟尘来评估火焰 是以铬为种子的。气相和空气对健康的影响 从火焰中喷出的颗粒状物质将是 与小组合作，使用各种生物测定进行调查。这个 热修复小组还将与生物学家合作 用于监测的连续“在线”生物传感器的开发和测试 来自简单的实验室燃烧系统的火焰后气体 氯代烃和铬。第二阶段的注意事项 该项目将针对相对新颖的、 商业热处理系统，可能应用于 马雷岛海军造船厂等地点的排污作业 在旧金山附近。将测试的两项技术是加热的 陶瓷床和催化系统。两者都在较低的温度下运行 而不是焚化炉。它们在不同的条件下没有得到很好的测试 氯气负荷和可能的金属污染。一个简单的实验 将开发用于加热陶瓷床和催化系统的模型 即平坦表面上的停滞点流动。测量 物种和温度将阐明氧化的性质 在这些技术中的工艺，特别是与蒸气成分 随时间变化，如在土壤排气作业中发现的。符合以下条件的条件 将对可能导致的健康危害进行评估。在现场可能会发现铅 被含铅汽油污染的汽车。铅蒸气对大气环境的影响 热处理和催化处理方法的操作将是 已评估。领先者的命运将被决定..

The fate of chromium in a simple, laminar diffusion flame will be studied in the first phase of the project. The oxidation state of the chromium aerosol that is formed in the flame will be determined as a function of the flame temperature and residence time. The impact of chlorine on the fate of the chromium will be tested in this inhomogeneous system. The possible inclusion of chromium into soot particles that are emitted from the flame will also be evaluated by collecting soot above a flame that is seeded with chromium. The health impact of the gas phase and particulate phase materials that are emitted from the flames will be investigated in collaboration with groups using various bioassays. The thermal remediation group will also collaborate with biologists in developing and testing a continuous, "on-line" bio-sensor for monitoring the postflame gases from simple laboratory combustion systems with chlorinated hydrocarbons and chromium. Attention in the second stage of the project will be directed towards the evaluation of relatively novel, commercial thermal treatment systems that have a possible application to soil venting operations at sites such as the Mare Island Naval Ship Yard near San Francisco. The two technologies that will be tested are a heated ceramic bed and a catalytic system. Both operate at lower temperatures than incinerators. They are not well tested under varying conditions of chlorine loading and possible metal contamination. A simple experimental model will be developed for the heated ceramic bed and catalytic systems viz., a stagnation point flow against a flat surface. Measurements of species and temperatures will elucidate the nature of the oxidation process in these technologies, especially with vapor composition that varies with time as found during soil venting operations. Conditions that may lead to health hazards will be evaluated. Lead may be found in sites that are contaminated with leaded gasoline. The impact of lead vapor on the operation of the thermal and catalytic treatment methods will be evaluated. The fate of the lead will be determined..