Dispersants are globally and routinely used as an emergency response to oil spills at sea, with the goal to enhance the dissolution of oil into water and stimulate oil biodegradation processes. Effective emulsification of oil and keeping it stable in seawater is an important requirement for the bioremediation of oil – a process largely dictated and driven by the activities of microorganism, in particular by oil-degrading bacteria. The impacts of dispersants on bioremediation, however, remain largely unexplored. Furthermore, dispersants approved for use in the UK, and those stocked worldwide by OSRL (Oil Spill Response Limited), are all produced through organo-chemical synthesis, and are commonly associated with environment incompatibility due to their associated low rates of biodegradation and toxicity to aquatic organisms.
The negative effects of chemical dispersants have necessitated the search for alternative dispersants that are more environmentally benign.
The focus of this project will be to provide the oil-gas industry, and oil-spill response agencies, with natural (bio-based) dispersants that are more eco-friendly and cheap to produce in large quantities to meet their demands. To meet this challenge, the project objectives are:
- To identify a handful of microbial-produced bio-dispersants that exhibit exceptional qualities for dispersing crude oil and stimulating oil-biodegradation processes in lab-based tests;
- To evaluate their effectiveness in field-based trials;
- To optimise bio-dispersant production by fermentation approaches.
Microbial-derived dispersants (aka bio-surfactants or bio-emulsifiers) offer a viable solution to the oil-gas industry as they can be produced from renewable feedstock or even waste streams and by natural fermentation processes. They are also readily biodegradable and display low eco-toxicity.