Washing of contaminated soils
US9108233B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 15, 2012 |
| Grant date | Aug 18, 2015 |
| Priority date | — |
| Expiry date | Jun 15, 2032 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB09C1/08
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
The process “Washing contaminated soils” solves the problem of cleansing and remediating soils and sediments and their fine fractions contaminated with toxic metals, using washing solution with chelating agents. The chelating agent forms water-soluble complexes with metals and thus facilitates metal removal from soils and sediments into the washing solution. In addition to toxic metals, the process according to the invention enables removal of organic pollutants from soils and sediments by using washing solution amended with surfactants, detergents or organic solvents in addition to chelating agents. The process according to the invention provides for simultaneous separation of the soil and sediment solid phase and used washing solution in a chamber filter press, and effective rinsing of the solid phase to remove all residual mobilized contaminants. The process according to the invention recycles chelating agents and process water in a closed process loop by applying a pH gradient and by using advanced oxidation processes for process water cleansing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.