US 5,342,146 A · Method and apparatus for treatment of contaminated soil particles

Abstract

A method and apparatus for decontaminating hydrocarbon contaminated soil particles comprises an upwardly directed conveyor which passes the soil through shredding knives to breakup the soil into a plurality of particles having a preselected maximum size. The stream of particles are directed against a downwardly inclined deflector to be directed downwardly toward a ground or concrete surface to form a growing conical pile of contaminated soil particles. A first set of spray nozzles, located above the particle stream, directs a spray of water containing decontaminating agents into the contaminated soil particle stream generally parallel to and within the stream of the contaminated soil particles, thus moistening the particles and assisting in producing a rolling action of the particles down the sides of the growing conical pile of particles. A second spray is utilized to direct a stream of water containing decontaminating agents against the underside of the stream of soil particles and the two sets of sprays provide a effective water barrier against the release into the atmosphere of aromatic materials carried by the contaminated soil particles.

Claims13

Dependent claims

The method of treating contaminated soil with an aqueous solution of decontaminating agents comprising:

breaking the contaminated soil into particles of substantially uniform maximum size;
forming a downwardly directed stream of contaminated soil particles impinging onto a selected surface in a manner to build a growing cone shaped mass of contaminated soil particles;
and
concurrently directing a spray of an aqueous solution of decontaminating agents into said stream in a direction substantially parallel to and within said stream of contaminates soil particles, whereby a portion of said aqueous spray moistens said particles by contact therewith and the remainder of said aqueous spray contacts the upper portions of said growing pile to produce moistening of said growing pile and assist in rolling of newly deposited particles down the sides of said cone shaped mass to expose more of each particle's surface area to contact by said aqueous solution of decontaminating agents.

1 more element

Apparatus for decontaminating soil contaminated by environmentally undesirable chemicals comprising, in combination,

means for shredding the contaminated soil into particles of substantially uniform maximum size;
means for conveying the contaminated soil particles at a selected rate to an overhead position relative to a non-contaminated surface;
means for downwardly discharging a stream of said contaminated soil particles from said overhead position to form a growing cone-shaped mass of contaminated particles on said non-contaminated surface;
means for concurrently directing a spray of an aqueous solution of decontaminating agents substantially parallel to and within said stream of contamined particles, thereby wetting said particles and assisting in downward rolling movement of particles down the sides of said cone shaped mass to expose more of the surfaces of said contaminated soil particles to contact with said aqueous solution;
means for detecting the water content of the contaminated soil particles prior to treatment;
means for detecting the water content of said contaminated soil particles in said cone shaped mass;
and
means for controlling the flow rate of said aqueous solution to maintain a selected minimum moisture content in said growing conical mass of contaminated soil particles.

5 more elements

Dependencies are inferred from the claim text.

Method and apparatus for treatment of contaminated soil particles

Life of this patent

Method and apparatus for treatment of contaminated soil particles

Life of this patent

Abstract

Claims13