Researchers from the School of Engineering at The University of Edinburgh have developed an innovative technological solution for the remediation of a wide range of hazardous chemicals polluting the soil and water at industrial sites [*]. Self-sustaining Treatment for Active Remediation (
STAR) aims to effectively eliminate contamination from industrial liquids, including coal tars, solvents, oils and petrochemicals.
STAR targets the destruction of the oily liquids that are the source of groundwater pollution by igniting them and controlling their slow burning within the soil. This new application takes advantage of the properties of
smouldering combustion (slow, low-temperature, flameless form of combustion).
STAR is self-tracking, self-sustaining and self-terminating. Once the contaminant has been ignited, the smouldering process proceeds only through the contaminated fraction of the soil by focusing itself directly on the pollutant. STAR supports itself during the process using the energy created by the smouldering. It then terminates once the contaminant fuel source has been exhausted or its oxygen source has been removed.
The initial proof of concept was funded by
Scottish Enterprise and, led by the two main inventors of the technology,
Prof Jason Gerhard and
Prof Jose Torero. The STAR technology has been proven multiple times at reactors of different sizes, ranging from 0.5 to 6 m in length.
According to Dr Jason Gerhard, “STAR promises to be technically effective as it is able to overcome barriers to remediation success that hinder many current approaches. It also promises to be particularly cost effective by avoiding ongoing energy provision and treatment of produced water or contaminants.”
Due to the increased costs for dumping hazardous wastes into landfill, the European market is estimated at £500M -£2 billion a year, whilst the North American market is easily five times more lucrative and growing.
For more information, these research paper can be read:
*
Self-sustaining Smoldering Combustion for NAPL Remediation: Laboratory Evaluation of Process Sensitivity to Key Parameters, Environmental Science & Technology 45 (7), pp. 2980-2986, 2011.
*
Self-Sustaining Treatment for Active Remediation: A Novel Technology for Non-Aqueous Phase Liquid
Contamination, Environmental Science and Technology 43, pp. 5871-5877, 2009.
*
Small-Scale Forward Smouldering Experiments for Remediation of Coal Tar in Inert Media, Proceedings of the Combustion Institute 32, pp. 1957-1964, 2009.
*
Smouldering Combustion Phenomena in Science and Technology, International Review of Chemical Engineering 1 (1), pp. 3-18, 2009.
[*] See page 10 of
Infite magazine published by Edinburgh Research and Innovation.
Smouldering combustion of liquids as a remediation concept is pending patent approval (UK Application 0525193.9, PCT Application PCT/GB2006/004591, and National Phase applications filed (e.g., USA 12/086323 and Europe 06820460.1; priority date 10th December 2005)).
