Venting test analysis using Jacob`s approximation
- Ohio Univ., Athens, OH (United States)
There are many sites contaminated by volatile organic compounds (VOCs) in the US and worldwide. Several technologies are available for remediation of these sites, including excavation, pump and treat, biological treatment, air sparging, steam injection, bioventing, and soil vapor extraction (SVE). SVE is also known as soil venting or vacuum extraction. Field venting tests were conducted in alluvial sands residing between the water table and a clay layer. Flow rate, barometric pressure, and well-pressure data were recorded using pressure transmitters and a personal computer. Data were logged as frequently as every second during periods of rapid change in pressure. Tests were conducted at various extraction rates. The data from several tests were analyzed concurrently by normalizing the well pressures with respect to extraction rate. The normalized pressures vary logarithmically with time and fall on one line allowing a single match of the Jacob approximation to all tests. Though the Jacob approximation was originally developed for hydraulic pump test analysis, it is now commonly used for venting test analysis. Only recently, however, has it been used to analyze several transient tests simultaneously. For the field venting tests conducted in the alluvial sands, the air permeability and effective porosity determined from the concurrent analysis are 8.2 {times} 10{sup {minus}7} cm{sup 2} and 20%, respectively.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 207896
- Journal Information:
- Journal of Environmental Engineering, Vol. 122, Issue 3; Other Information: PBD: Mar 1996
- Country of Publication:
- United States
- Language:
- English
Similar Records
Passive bioventing driven by natural air exchange
Vapor extraction, air sparging, and bioventing in combination form a technically and cost effective scenario to remediate petroleum hydrocarbons