US 11,077,422 B2 · Spalling composite particles and methods of using them

Abstract

Composite particles contain a natural stone or aggregate core and a coating of two or more sorbent layers collectively containing at least two distinct kinds of sorbent materials effective for sorbing two distinct contaminants. One or both sorbent layers may be mixed with a water-absorbent, swellable clay that, upon contact with water, causes spalling or disintegration of the coating layer to release the sorptive material into a body of water such as a pond, ditch, stream, or riverbed. Additional swellable or protective layers may also be present. The composite particles are deployed into a pond, ditch, river, or streambed where the core of natural stone remains in the riverbed. The sorptive materials of the two different sorbent layers sorb and fix a wide range of contaminants, including both the heavy and light-weight hydrocarbons, from the water, and settle as a fine sediment. The sediment with sorbed contaminants is then removed by means such as hydraulic collectors or dredging.

Claims22

Dependent claims

A spallable composite particle, comprising:

a natural stone or aggregate core at least partially coated with two or more coating layers, including:
a first layer of hydratable, swellable clay material over the core,
an inner sorbent layer disposed over the first layer of hydratable, swellable clay material, the inner sorbent layer containing a first sorptive material for binding a first type of contaminant,
a second layer of hydratable, swellable clay material over the inner sorbent layer, and
an outer sorbent layer disposed over the second layer of hydratable, swellable clay material, the outer sorbent layer containing a second sorptive material for binding a second type of contaminant, the second sorptive material being different than the first sorptive material.

2 more elements

A composition comprising a plurality of spallable composite particles, wherein:

a first type of composite particle comprises
a natural stone or aggregate core at least partially coated with two or more coating layers, including
a first layer of hydratable, swellable clay material over the core,
an inner sorbent layer disposed over the first layer of hydratable, swellable clay material, the inner sorbent layer containing a first sorptive material for binding a first type of contaminant, the first sorptive material having a sorption coefficient effective for sorbing the first type of contaminant,
a second layer of hydratable, swellable clay material over the inner sorbent layer, and
an outer sorbent layer disposed over the second layer of hydratable, swellable clay material, the outer sorbent layer containing a second sorptive material for binding a second type of contaminant, the second sorptive material being different than the first sorptive material, and the second sorptive material having a sorption coefficient effective for sorbing the second type of contaminant;
and
a second type of composite particle comprises
a natural stone or aggregate core at least partially coated with two or more coating layers, including
a first layer of hydratable, swellable clay material over the core,
an inner sorbent layer disposed over the first layer of hydratable, swellable clay material, the inner sorbent layer containing the second sorptive material,
a second layer of hydratable, swellable clay material over the inner sorbent layer, and
an outer sorbent layer disposed over the second layer of hydratable, swellable clay material, the outer sorbent layer containing the first sorptive material.

10 more elements

Dependencies are inferred from the claim text.

Spalling composite particles and methods of using them

Life of this patent

Spalling composite particles and methods of using them

Life of this patent

Abstract

Claims22