Abstract Cognis, part of the Henkel group, has developed a liquid product with lipophilic characteristics that can be applied to a number of environmental clean-up problems: oil contaminated soils, contaminated coast lines and off-shore drilling sites; and, in the event of large-scaled accidents, it can be combined with physical and mechanical pre-cleaning methods.
The Cognis product emulsifies hydrocarbons, making them disperse in water and thereby promoting biodegradation. With organic bound phosphorous and nitrogen the product also acts as a nutrient source for microbes. It forms a layer around contaminant molecules, thus reducing leaching of nutrients and fixing microbes to the contamiants. It boosts total cell count of local oil-devouring bacteria rapidly so that the natural self-cleaning capacity rises to a multiple acceleration. The product itself is of outstanding eco-compatibility: it is not washed-out into the groundwater, it does not remobilize contaminants, and it s active ingredients have a food and/or fodder permittance.
A large-scaled pilot test has shown that common agricultural fertilizers are not useful for bioremediation, because mineral nutrients were washed-out, and the biodegradation process was not enhanced.
Beside more cost intensive conventional ex-situ and in-situ bioremediation techniques, a special low cost technology was developed in a joint effort with IABG. This technique is especially suitable for contaminated zones located no more than 2 m below soil surfaces (D.R.O.P.: Decontamination and Revitalisation of Oil Polluted Land). While the product is applied by means of sprinkling systems and subsequently mixed into the soil, this technology is even applicable for water protection areas, wetlands or nature reserves. The overall cost of this measure is only a third of other well-known in-situ methods.
Introduction Sites which are contaminated with mineral oils or fuels not only possess a threat to man and the environment, in many cases they prevent investments in those sites for their redevelopment. The remediation of those sites often imposes costs that exceed their actual value. As a result, many sites remain unused.
Biodegradation of oil contaminants is a natural process but needs time, often decades. To speed up the process and reduce remediation time to weeks resp. months Cognis has developed a special type of degradation enhancer.
Beside more cost intensive conventional ex-situ and in-situ bioremediation techniques, Cognis and IABG developed in a joint effort a special low cost technology. This technique is especially suitable for contaminated zones located no more than 2 m below soil surfaces (D.R.O.P.: Decontamination and Revitalization of Oil Polluted Land). This technology is even applicable for water protection areas, wetlands or nature reserves.
The measure has been registered for patent and supports like enhanced natural attentuation the present self-cleaning ability of the soil micro-organisms due to the effect of a liquid, lipophilic nutrient product developed by Cognis.
So far, the remediation measure has been successfully applied to sites with mineral oil pollution located predominantly in the unsaturated soil horizon, for instance, contamination as a result of the big floods in Bavaria (1999), at a former military tank farm and currently at drilling sites in Ecuador and Brunai.