This technology is available from Temarex Corporation.

BIOREMEDIATION OF CONTAMINATED SOIL

Title: BIOREMEDIATION OF POLYCYCLIC AROMATIC HYDROCARBON CONTAMINATED SOIL

Inventor(s): S. Lee, T. Cutright

Disclosure 229 U.S. Patent 5,427,944

Disclosure 229-CIP U.S. Patent 5,508,194

This novel bioremediation process utilizes a mixed bacteria culture of Achromobacter sp. and Mycobacterium sp. which has been found to be especially efficient for effecting rapid biodegradation polycyclic aromatic hydrocarbon (PAH) contaminants.

The mixed bacteria culture can be utilized for in situ or ex situ bioremediation of contaminated soil, or in any of various conventional bioreactors to treat contaminated liquids such as landfill leachates, groundwater or industrial effluents. In addition, the mixed bacteria culture can be used in combination with other commonly used microorganisms to remove or biodegrade hazardous contaminants other than PAHs which are/or might be present in soil, groundwater, or other material being remediated.

One of the key features of the invention is that the bacteria, the nutrients used to sustain growth of the bacteria, and the products of the biodegration of the polycyclic aromatic or other hydrocarbons are all substantially harmless to the environment. The mixed bacteria culture provides an environmentally safe and inexpensive means for rapidly and effectively eliminating a variety of PAH contaminants from the environment.

The bacteria culture is especially useful because of its unusual ability to rapidily metabolize a variety of PAHs. Examples of PAHs which can be biodegraded include any of the various aromatic compounds containing multiple ring structures such as pentalen, indene, naphthalene, azulene, heptalene, biphenylene, asym-indacene, fluorene, phenalene, phenanthrene, anthracene, fluoranthene, acephenanthrylene, aceanthrylene, triphenylene, pyrene, chrysene, naphthacore and the like. PAHs are generally present in and derived from fossil fuels, especially coal and petroleum. Relatively high concentrations of PAHs are found in coal-tar pitch, petroleum and coal-tar naphtha, and various various other high-boiling point petroleum fractions, as well as various products derived therefrom including roofing pitch, sealants, road tars, asphalts, pipe coatings, water-proofing materials, dyes, pesticides, paint additives and wood preservatives.

Potential applications of the invention include soil remediation at manufactured gas plant sites, coke oven sites, petroleum refineries, fuel depots, gas stations, and other industrial sites.