Patent · US Expired

Process for treating contaminated soil

US5303871A · kind A · utility

15Cited by
11References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 14, 1992
Grant dateApr 19, 1994
Priority date
Expiry dateMay 14, 2012

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB03D1/1475
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A process for the purification of soil contaminated with organic material is provided. The preferred process generally involves superposed attrition and classification processes, which lead to removal and concentration of highly contaminated fractions. The process may also include a step of flotation whereby hydrophobic materials in the soil are released to an interface with air bubbles, and are floated to the top of a flotation cell. In preferred processes according to the present invention, soil to be treated is extracted from a contaminated site, and is broken into relatively small particles. These particles are preferably treated in attrition and classification steps, to remove fine, slow settling contaminated materials such as wood and fine soil materials. The resulting isolated coarser materials are then treated by flotation for a final polishing step. The process is particularly well adapted for use in treating soils contaminated with oil and grease materials containing PCP therein, from wood treatment plants or the like.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.