US 11,453,010 B2 · Solid waste treatment process

Abstract

In an apparatus and process described, an organic fraction of solid waste is separated from light contaminants such as plastics and heavy contaminants such as grit. The organic fraction is subsequently processed by anaerobic digestion, which converts volatile solids to gas. In a first stage of the process, the waste is processed through a separator such as a vertical mill, which removes light fraction contamination, reduces organics particle size and dilutes the waste to thereby produce a slurry. In a second stage of the process, the slurry passes through a grit removal system, which removes heavy and settleable material, for example by way of a hydrocyclone. The light and heavy fraction contaminants are not carried through to the digestion process. The particle size of the organics is also reduced to facilitate digestion and the slurry has a dry solids concentration suitable for anaerobic digestion.

Claims20

Dependent claims

A system for processing solid waste comprising,

a light fraction separator configured to separate the solid waste into a light fraction and a slurry;
a grit removal system to produce a de-gritted slurry, the grit removal system comprising one or more grit staging tanks and a hydrocyclone, the one or more grit staging tanks comprising a first portion and a second portion, wherein:
the first portion is in fluid communication with the light fraction separator to accept the slurry and configured to serve as a staging tank before the slurry is sent to the hydrocyclone,
the hydrocyclone is in fluid communication with the first portion and configured to separate the grit from the slurry, and,
the second portion is in fluid communication with the hydrocyclone and configured to accept an overflow from the hydrocyclone,
a recycle flow path connecting the second portion to the first portion;
and,
an anaerobic digester configured to receive the de-gritted slurry from the grit removal system.

5 more elements

Dependencies are inferred from the claim text.

Solid waste treatment process

Life of this patent

Solid waste treatment process

Life of this patent

Abstract

Claims20