For a brief summary of the basics of petroleum bioremediation follow this link Basics of Petroleum Bioremediation
Petrox bioremediation is used to remove petroleum contamination from soil and water under many different conditions. From surface spills to deep soil and ground water contamination, Petrox has successfully removed the contamination and environmental risk. This summary of case studies demonstrates the applicability of Petrox bioremediation to the full range and life cycle of petroleum spills. Click here to view the document.
Cl-Out bioremediation was used to remove PCE from ground water at a dry cleaners in Vermont. CL-Out micorbes were selected for bioremediation of the site because they are compatible with the natural aerobic aquifer conditions. One application of CL-Out bioaugmentation reduced the PCE concentration by 90% in less than 6 months without increasing the vinyl chloride concentrations.
The following table summarizes the process of aerobic cometabolism of PCE. The pre-bioaugmentation sampling showed aerobic conditions and a low population of Pseudomonas microbes. After bioaugmentation the Pseudomonas population was higher. As the microbes consumed the dextrose substrate and produced the oxygenase enzymes necessary for PCE destruction, the ORP and PCE concentrations decreased. Six months after the bioaugmentation, the microbial population returned to the pre-bioaugmentation conditions.
Petrox EC is a product that combines a surfactant with petroleum-degrading microbes to improve separate phase oil recovery and bioremediation of residual oil. The combined approach improves the rate of oil removal from soil and other subsurface media and establishes a beneficial petroleum-degrading microbial population that will treat tightly bound or deeply penetrated oil.
Petrox EC has been used in combination with periodic LNAPL extraction by pumping or bailing. In field applications the surfactant effect has increased the LNAPL recovery rate by more than 10 fold.
Petrox EC has also been used to improve the efficiency of air sparging by flushing oil from the sediment surface for sparging and vapor phase recovery.
Cometabolism is considered the indirect beneficial destruction of a contaminant compound by a microorganism that is growing on another substrate. While the benefit may be fortuitous, cometabolism can be directed and controlled to improve the environmental benefit.
CL Solutions has used cometabolism in three ways for bioremediation of different types of compounds.
• CL-Out® is a consortium of microbes that cometabolize chlorinated solvents under aerobic to anoxic conditions. The microbes metabolize dextrose as a primary substrate and constituatively produce dioxygenase enzymes that convert PCE, TCE and other chlorinated aliphatic compounds into organic acids that are metabolized.
• CL-Out® has been used to remove perchlorate from soil and ground water while growing on a substrate and using perchlorate for respiration. The substrate provides a carbon source and the perchlorate reduced by respiration. This approach can also be used for denitrification.
• In a novel approach, a simple sugar can be used as a substrate to support microbial growth when the concentrations of the target contaminant are too low to support an effective population density. This approach was used for pesticide bioremediation when the ground water concentrations were less than 0.1 µg/L and the remediation goal was 0.002 µg/L.