In a large soil washing machine is then treated soil with the produced acid and release harmful pollutants. This acid is primarily designed to remove arsenic, a highly toxic substance often found where industries for wood treatment were active. The method also works well for removing zinc, lead and copper from the soil.
– Detergents made of organic materials are both more cost effective and environmentally friendly than conventional detergents, says Anders Lagerkvist, Professor in Waste Science and Technology at the University.
Another advantage of this method is that biogas is produced in the purification process which can eventually do the processing energy self-sufficient. Large soil can be decontaminated with this method while extensive transport is avoided.
- After the wash process the soil is clean and the harmful residues collected in the wash water which runs in a digester, where the detergent is broken down to form gas. The result is a slam where pollutants are concentrated several thousand times that of the soil, says Anders Lagerkvist.
The method works best on moderately contaminated areas with levels of 10-20 percent over the acceptable level. Is ground heavily polluted still works the usual method better, that is, to dig up the soil masses and put them in landfills. Today, work with the soil remediation is conducted in the most polluted areas, but with this new and smarter technology, less contaminated areas, as there are tens of thousands of, can be treated.
It's Anders Lagerkvist, Lulea University of Technology, and Anders Kihl, Rank-Sells, who invented this method recently granted a patent on the technology. Even the Swedish Geotechnical Institute and impregnation company Stab Suecia Southern We have participated in the research project. Formas has funded the project.