Utilization of the PHOSterTM Process to improve In Situ Bioremediation of Petroleum Hydrocarbons
B. B. Looney, S. Eaton, J. Haselow, and D. Klemm
PHOSterTM is a patented gas-phase nutrient delivery system that can be used to control the addition of vapor phase phosphorus and improve in situ bioremediation processes. PHOSterTM can be easily and cost-effectively added to most existing biosparging or bioventing systems to provide the phosphorus that is often lacking for an optimally healthy microbial environment. Traditional approaches for adding phosphate to sites are based on addition of liquid fertilizer or phosphoric acid vapors. Such systems have been shown to influence very small areas and often result in overstimulation of the microbial population, which can lead to undesirable effects such as formation clogging. The PHOSterTM system uses a relatively safe form of organic phosph te, triethylphosphate or TEP. TEP is added to an air injection stream by contacting or infusing the vapors from the liquid. With PHOSterTM, the presence of the ethyl groups on the phosphate reduces the nutrient's dissolution rate into water and provides a "time released" stimulation and prevents clogging, and because the phosphorus is in a gas form, it is more readily dispersed in the formation. PHOSterTM has been successfully utilized in three states (South Carolina, Michigan, and New York) on petroleum hydrocarbon and trichloroethene contamination. A goal of a fourth test that is underway in Panama City, Florida at a gasoline distribution terminal is to improve the in situ remediation of BTEX and eliminate fugitive emissions from a multipoint airsparging process.
AAPG Search and Discover Article #91019©1996 AAPG Convention and Exhibition 19-22 May 1996, San Diego, California