초록 ▼

The present invention is a process for in situ biodegradation of spilled hydrocarbons. The process involves drawing oxygen into a hydrocarbon contaminated zone. A borehole is drilled into the contaminated zone and gas is evacuated at high rates out of the borehole to thereby draw oxygen from the ear

The present invention is a process for in situ biodegradation of spilled hydrocarbons. The process involves drawing oxygen into a hydrocarbon contaminated zone. A borehole is drilled into the contaminated zone and gas is evacuated at high rates out of the borehole to thereby draw oxygen from the earth\s surface and through the contaminated zone. Surprisingly, the carbon dioxide concentration in the evacuated gas remains high even at the high flow rates. The rate of gas evacuation in the present process is maintained sufficiently high so that the hydrocarbon biodegradation rate is within at least 50% of the maximum hydrocarbon biodegradation within the zone. The process can be applied to both porous and nonporous soils having relatively low water and gas permeability.

대표청구항 ▼

An in situ process for biodegrading hydrocarbons by drawing oxygen into an undisturbed hydrocarbon contaminated zone in a fluid permeable soil, comprising: establishing a borehole extending from the earth\s surface through a hydrocarbon contaminated zone having hydrocarbon degrading microbes therein

An in situ process for biodegrading hydrocarbons by drawing oxygen into an undisturbed hydrocarbon contaminated zone in a fluid permeable soil, comprising: establishing a borehole extending from the earth\s surface through a hydrocarbon contaminated zone having hydrocarbon degrading microbes therein; lining said borehole with a fluid impermeable liner coaxially spaced and sealingly connected to the inside surface of said borehole and extending from the earth\s surface to the hydrocarbon-contaminated zone; said liner including a fluid permeable portion extending from the lower end thereof and through at least a portion of said hydrocarbon contaminated zone, fluidly connecting a source of negative pressure to said fluid impermeable liner; evacuating gas from said borehole through the fluid permeable portion of said liner at a rate sufficient to draw air from the earth\s surface into the hydrocarbon containing zone; and adjusting the flow rate of the evacuated gas so that the amount of hydrocarbon biodegradation therein is within 50% of the maximum hydrocarbon biodegradation rate as detected by the volume of carbon dioxide in the evacuated gas.