Vadose Zone Remediation by Sustainable Soil Vapor Extraction

MicroBlowers (U.S. Patent No. 6,971,820) are ideal for remote locations with limited or no ancillary infrastructure.  By using renewable sources of energy, the MicroBlower eliminates the need for generators and fuel storage at remote locations.  The MicroBlower design also eliminates ancillary infrastructure that are generally required to run conventional ASVE systems in remote areas.  MicroBlowers offer the advantage of a reduced carbon footprint and very low O&M expenses.MicroBlower uses a small, low power vacuum blower to extract or inject gases into the subsurface for characterization or remediation.  While similar in design to an active soil vapor extraction (ASVE) blower, the MicroBlower is a low-cost alternative designed to run on renewable sources of energy such as solar and wind energy to treat volatile organic compound (VOC) contamination in the unsaturated zone. By using renewable sources of energy, the blowers eliminate the need for an external power supply and other ancillary infrastructure generally required for conventional ASVE systems. With the solar or wind option, a small battery bank stores power for when the sun or wind energy is inadequate. The MicroBlower can also run on a 24-volt DC power supply.  The small size and very low O&M expenses of the system make MicroBlower useful for long-term cleanup operations, particularly where mass transfer limits the rate of remediation.

MicroBlower Model No. MB300MicroBlower Model No. MB300Ideal for long-term remediation

Pumping: The pump is capable of producing flows greater than1 scfm at pressures or vacuums typical of subsurface situations.

Power: The system requires less than 40 watts of power; easily produced by a small photovoltaic panel, battery or wind turbine.

Size: The units are small and unobtrusive for long-term operations - 8 inches tall, 6 inches wide, virtually noiseless but powerful enough to do the job.

Widespread Potential

The MicroBlower enables the use of simple, low-cost soil vapor extraction in shallower areas than previously considered possible.  One of the greatest potentials for MicroBlower is in treatment polishing of an area treated by an expensive, large blower system that still has residual contamination. Installation of an economical MicroBlower system to finish the cleanup at greatly reduced costs, allows owners to use their larger system in other areas or sites where they can produce greater returns.  The MicroBlower also can remediate sites that are smaller than the capacity of typical, large blower systems.

Example InstallationsExample Installations
Features and Benefits

  • Made in the USA
  • Powerful 24 VDC brushless motor
  • Robust construction
  • Solar, wind or conventional power
  • Great for remote applications
  • Great for power challenged sites
  • No trenching required
  • Easily integrated activated carbon system
  • Offers significant cost savings
  • Low carbon footprint
  • Minimal O&M expenses

Cost Savings

The MicroBlower offers significant cost savings to the groundwater remediation industry. Presently, there are no regulations concerning the contaminants in the vadose zone.  However, if the vadose zone is not remediated, contamination will migrate downward and contaminate / recontaminate the groundwater. With the groundwater no longer in compliance, responsible parties must bear the cost of remediating the groundwater.  By installing the MicroBlower, the risk of the groundwater being initially contaminated or recontaminated from the vadoze zone would be significantly mitigated.

Verified performance

During a 10-month period, one MicroBlower removed 234 pounds of volatile organic compounds from a contaminated plume beneath a site in South Carolina.

Soil Gas VOC ConcentrationsSoil Gas VOC Concentrations

Model No. MB300 Performance Curves

Note:  Data presented represents blower performance at STANDARD AIR DENSITY, .075 lb/ft3 (29.92” Hg, Sea Level, 68° F).