Dry Barriers for Waste Containment

废物遏制的干屏障

• 批准号: 9800255
• 负责人: Craig Benson
• 金额: $ 28万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-06-15 至 2002-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9800255&HistoricalAwards=false
• 关键词: Dry; Barriers; Waste; Containment

9800255 Craig Composite caps consisting of a geomembrane and compacted clay layer are often used for closure of landfills and for isolation of contaminated soil and waste because they are very effective at minimizing percolation. However, composite caps are expensive. As a result, interest has developed in less costly and equally effective alternative caps constructed almost entirely with earthen materials. The objective of the proposed study is to investigate fundamental factors affecting the behavior of a new alternative earthen cap called a "dry barrier," a special type of earthen cover where airflow is used to remove intruding water. This design permits the use of thinner layers while still preventing percolation, even during the most stressful periods, such as snowmelt and heavy winter rainfalls. As a result, thinner layers are required and the cost of the cap is lower. Designing dry barriers requires an understanding of the "in situ evaporation" process and flow of air laden with water vapor in porous media. Moreover, models need to be developed for use in design. This study addresses these issues through experimental work and development of computer models. Experiments will be conducted to characterize the "in situ evaporation process" as a function of soil type, water content, air stream velocity, and humidity of the air stream. Models will be developed based on the experimental work and verified using large-scale laboratory tests and a field experiment. Results of this study will demonstrate the benefits of using dry barriers and provide analytical tools and data for their design. ***

9800255 CRAIG复合盖由土工膜和压实的粘土层组成的盖子通常用于封闭垃圾填埋场和隔离污染的土壤和废物，因为它们在最小化渗透方面非常有效。 但是，复合盖很昂贵。 结果，兴趣在几乎完全用泥土材料构建的昂贵且同样有效的替代上限上发展。 拟议的研究的目的是研究影响新替代泥土帽的行为的基本因素，称为“干屏障”，这是一种特殊类型的泥土覆盖物，用于去除侵入水。 这种设计允许使用较薄的层，同时仍然可以防止渗透，即使在压力最大的时期，例如融雪和冬季大雨。 结果，需要更薄的层，并且盖的成本较低。 设计干屏障需要了解多孔介质中水蒸气的“原位蒸发”过程和载有水蒸气的流动。 此外，需要开发用于设计的模型。 这项研究通过实验工作和计算机模型的开发来解决这些问题。 将进行实验，以将“原位蒸发过程”表征为土壤类型，水含量，空气流速度和空气流的湿度的函数。 模型将根据实验工作开发，并使用大型实验室测试和现场实验进行验证。 这项研究的结果将证明使用干屏障并为其设计提供分析工具和数据的好处。 ***