Light weight medium for growing microorganisms

Abstract

A light weight medium for growing microorganisms includes a mass of polymeric foam, such as a polyurethane foam, having an outer region enclosing an inner region. A plurality of fragments of an inorganic material, such as sand, are at least partially embedded in the outer region. The light weight medium may be used to support growth of microorganisms in a wide variety of biological and/or biochemical processes, or may be used without microorganisms in chemically treating wastes.

1 . A medium for treating wastes, comprising: 
 a mass of polymeric foam, said mass having an, outer region surrounding a core; and    a plurality of fragments of an inorganic material, said inorganic material being selected from the group comprising activated carbon, pure elemental fragments, clay, limestone and irons salts, a first portion of said fragments adhering only to an outer surface of said outer region, a second portion of said fragments being partially embedded in said outer region, and a remaining portion of said fragments being wholly embedded in said outer region, wherein substantially none of said fragments are contained within said core.