US 4,951,417 A · Method of contaminated soil remediation and apparatus therefor

Abstract

A method and apparatus for on-site remedial soil restortation activity of a work site contaminated with volatile organic compounds. Soil is removed from the ground and hauled to an initial feed hopper whereat it is conveyed to an inlet end of a hollow rotating cylinder having plural flights therein for effecting a moving of the contaminated soil lengthwise of the rotating cylinder toward an outlet end. The soil is heated as it tumbles about in the cylinder and the volatile organic compounds (VOCs) are volatilized inside the rotating cylinder. The soil exiting the outlet end of the cylinder is thence recirculated through the rotating cylinder and thereafter fed to a conveying mechanism, whereat the cleaned soil is delivered to a selected location. The hot gases are scrubbed to remove therefrom any organics, acids and phosgenes and, if present, soil fines. The now cleansed gases are thereafter allowed to escape into the atmosphere as clean air.

Claims72

Dependent claims

A method of on-site remedial soil restoration activity of a work site contaminated with volatile substances disposed at said site at an earlier time, which substances have soaked into said soil, the steps comprising:

removing contaminated soil from the ground and transporting it to an initial feed hopper means;
conveying said contaminated soil from said initial feed hopper means to an inlet and of the interior of a low temperature thermal treatment chamber with the soil mixing capability;
exposing granules of the soil to the ambient temperature in the chamber which is sufficient to cause a volatilization of said volatile substances but insufficient to result in any significant incineration, thereby causing said volatile substances to be volatilized inside said chamber;
evacuating the interior of said chamber by drawing hot gases and entrained soil fines containing the volatilized substances therefrom;
following an exposing of the granules of the soil to the ambient temperature in said chamber, conveying the now cleansed said from said chamber to a selected location;
extracting any organics, acids and phosgenes present in the gas stream containing the volatilized substances;
and
discharging the now clean gas stream into the ambient atmosphere.

5 more elements

An apparatus for on-site remedial soil restoration activity of a work site contaminated with volatile substances disposed at said site at an earlier time, which substances have soaked into said soil, comprising:

an initial feed hopper means;
a low temperature thermal treatment chamber means adapted to receive contaminated soil at an inlet end and having heating means for heating said contaminated soil to an ambient temperature which is sufficient to cause a volatilization of said volatile substances but insufficient to result in any significant incineration;
first means for conveying said contaminated soil from said initial feed hopper means to said inlet end of the interior of said low temperature thermal treatment chamber means;
soil mixing means in said low temperature thermal chamber means for exposing granules of the soil to the ambient temperature in said chamber, said volatile substances being volatilized inside said chamber;
evacuating means for evacuating the interior of said chamber by drawing hot gases and entrained soil fines containing the volatilized substances therefrom;
second means for conveying the now cleansed soil, following an exposing of the granules of the soil to the ambient temperature in said chamber, from said chamber to a selected location;
extracting means for extracting any organics, acids and phosgenes present in the gas stream containing the volatilized substances;
and
discharging means for facilitating a discharging of the now clean gas stream into the ambient atmosphere.

6 more elements

Dependencies are inferred from the claim text.

Method of contaminated soil remediation and apparatus therefor

Life of this patent

Method of contaminated soil remediation and apparatus therefor

Life of this patent

Abstract

Claims72