March 28, 2011


Taisei Establishes On-Site Remediation Method for Cyanide-Contaminated Soil

Keywords: Chemicals Non-manufacturing industry 

Japan's Taisei Corp., a leading engineering and construction company, announced on November 22, 2010, that through collaboration with Toho Gas Co. it established a new remediation method for cyanide-contaminated soil. The new method achieves complete on-site particle classification (see Note) and remediation of contaminated soil without carrying the soil off-site by using additives in the cleaning water. It also reduces remediation costs by 30 to 40 percent compared to conventional methods.

Before this new method, Taisei had already established an on-site remediation technology for cyanide-contaminated strata located below the water table (saturated zone). The same technology cannot be applied to contaminated soil above the water table (unsaturated zone), however, because cyanide compounds that become dissolved in the cleaning water below the water table adhere back to the soil. Consequently, there has been no other effective treatment option but to carry soil above the water table off-site, which is not recommended under the Soil Contamination Countermeasures Law revised in April 2010 . This restriction increased need for an on-site soil remediation technology.

Cyanide compounds with high-water solubility react with additives to form low-soluble salts. Utilizing this chemical characteristic, Taisei developed a cleaning and separation system with a function for collecting the salt as sediments, and confirmed the effect of this system through verification tests.

Note: Particle classification as mentioned here is the sorting out of remediated coarse soil particles from fine particles having concentrated levels of pollutants.

Kurita Develops New Technology to Detoxify Contaminated Soil and Groundwater (Related JFS article)
Innovative Technology Treats Fluoride-Contaminated Soil (Related JFS article)

Posted: 2011/03/28 06:00:15 AM



Taisei Corp. official website