What is bioventing technique?

What is bioventing technique?

Bioventing is a technique used to add oxygen directly to a site of contamination in the vadose zone (unsaturated zone). In bioventing alone, air is injected at very low flow rates into the contaminated zone to promote biodegradation.

What is bioventing a type of?

3.1 Bioventing. Bioventing is a type of in situ bioremediation technique that stimulates the aerobic degradation process. It enhances the intrinsic capability of indigenous microflora to degrade the organic contaminants adsorbed to soil by introducing oxygen into an unsaturated zone.

How is SVE different from bioventing?

When extraction wells are used for bioventing, the process is similar tosoil vapor extraction (SVE). However, while SVE removes constituents primarily through volatilization, bioventing systems promote biodegradation of constituents and minimize volatilization (generally by using lower air flow rates than for SVE).

What is meant by Biosparging?

Biosparging. Biosparging, like bioventing, is an in situ remediation technique that supplies oxygen and nutrients (if needed) to contaminated soils to promote aerobic biodegradation of contaminants (i.e. petroleum hydrocarbons) by indigenous microorganisms.

What is Biosparging in bioremediation?

Microbial Bioremediation Biosparging: This involves the injection of air under pressure below the water table to increase ground water oxygen concentrations and to enhance the rate of biological degradation of contaminants by naturally occurring bacteria.

Which plant is used for Rhizofiltration?

A few examples of plants that are employed for rhizofiltration are sunflower, tobacco, spinach, rye and Indian mustard. Plant species besides hyperaccumulators can also be used, as the heavy metals need not be translocated to the shoots (Henry, 2000).

What is Rhizofiltration in phytoremediation?

Rhizofiltration is a form of phytoremediation that involves filtering contaminated groundwater, surface water, and wastewater through a mass of roots to remove toxic substances or excess nutrients.

How is Biosparging done?

Biosparging consists of injecting pressurized air or gas into a contaminated zone in order to stimulate in situ aerobic biological activity. This remediation technique applies to dissolve and residual contamination in the saturated zone, and targets chemical compounds that can be biodegraded under aerobic conditions.

What is Biosparging used for?

Biosparging, like bioventing, is an in situ remediation technique that supplies oxygen and nutrients (if needed) to contaminated soils to promote aerobic biodegradation of contaminants (i.e. petroleum hydrocarbons) by indigenous microorganisms.

What is rhizosphere and Rhizoplane?

rhizoplane – the root surface including associated soil particles (Estermann and McLaren 1961; Clark 1949) rhizosphere – the zone of chemical, biological, and physical influence generated by root growth and activity.

What is bioventing?

Bioventing: Bioventing is a promising new technology that stimulates the natural in situ biodegradation of any aerobically degradable compounds by providing oxygen to the existing soil microorganisms. It uses low air flow rates to provide only enough oxygen to sustain microbial activity.

What is the bioventing Design Manual for the EPA?

BIOVENTING DESIGN U.S. EPA. MANUAL: BIOVENTING PRINCIPLES AND PRACTICE VOLUME II. BIOVENTING DESIGN. U.S. Environmental Protection Agency, Washington, DC, EPA/540/R-95/534b, 1995. The results from bioventing research and development efforts and from the pilot-scale bioventing systems have been used to produce this two-volume manual.

What are the cost drivers for bioventing?

Costs are highly dependent on the treatment area, depth of contamination, and soil lithology, which influence the number and design of blowers, vent wells, and soil gas monitoring points. Major cost drivers for bioventing can be divided into two categories including upfront costs and operation and maintenance costs.

What is bioventing and soil vapor extraction?

Figure 20.27B shows a remediation strategy that is based on bioventing (low flow rates) or soil vapor extraction (high flow rates). Bioventing is a technique used to add oxygen directly to a site of contamination in the vadose zone (unsaturated zone).