Production of biogas from organic materials

• US 9,879,285 B2
• Filed: 03/30/2016
• Issued: 01/30/2018
• Est. Priority Date: 07/20/2015
• Status: Active Grant

• Current Assignee: Anaergia Inc.
• Original Assignee: Anaergia Inc.
• Inventors: De Lima Vasconcellos, Marcelo, Josse, Juan Carlos
• Primary Examiner(s): Prince, Fred
• Application Number:
  US15/085,381
• Publication Number:
  US 20170022522A1
• Time in Patent Office: 671 Days
• Field of Search: 210603, 210608, 210609
• CPC Class Codes: B03B 5/34 Applications of hydrocyclones
• CPC Class Codes: B03B 9/06 specially adapted for refuse
• CPC Class Codes: B09B 3/00 Destroying solid waste or transforming solid waste into something useful or harmless
• CPC Class Codes: B09B 5/00 Operations not covered by a single other subclass or by a single other group in this subclass
• CPC Class Codes: C02F 11/04 Anaerobic treatment; Production of methane by such processes
• CPC Class Codes: C02F 2209/03 Pressure
• CPC Class Codes: C02F 2303/24 Separation of coarse particles, e.g. by using sieves or screens
• CPC Class Codes: C05F 9/04 Biological compost
• CPC Class Codes: C12M 21/04 for producing gas, e.g. biogas digesters for manure with production of biogas A01C3/028, biological treatment of water, waste water or sewage C02F3/00, C02F11/02, preparation of natural gas or syngas C10L3/06, C10L3/10
• CPC Class Codes: C12M 45/02 by mechanical forces; Stirring; Trituration; Comminuting crushing, pulverizing, disintegrating in general B02C
• CPC Class Codes: C12P 3/00 Preparation of elements or inorganic compounds except carbon dioxide recovery of carbon dioxides as by-products C12F3/02
• CPC Class Codes: Y02A 40/20 Fertilizers of biological origin, e.g. guano or fertilizers made from animal corpses
• CPC Class Codes: Y02E 50/30 Fuel from waste, e.g. synthetic alcohol or diesel
• CPC Class Codes: Y02P 20/145 the feedstock being materials of biological origin
• CPC Class Codes: Y02W 30/20 Waste processing or separation
• CPC Class Codes: Y02W 30/40 Bio-organic fraction processing; Production of fertilisers from the organic fraction of waste or refuse
• CPC Class Codes: Y02W 30/52 Mechanical processing of waste for the recovery of materials, e.g. crushing, shredding, separation or disassembly

Abstract

Waste or organic material is compressed at a pressure sufficient to burst cells, for example 50 bar or more, and separated into a dry fraction and a wet fraction. The wet fraction is treated in an anaerobic digester to produce biogas after removing grit. The wet fraction is diluted, preferably with sludge, before it is degritted. Optionally, floatables are removed from the fraction before it is added to the digester.

Claims

1. A process comprising steps of,

pressing solid waste containing organic material to separate the solid waste into a wet fraction containing organic material that is compressed through perforations in a wall of a compression chamber and a dry fraction;

diluting the wet fraction;

degritting the wet fraction; and

,

treating the wet fraction in an anaerobic digester.

2. The process of claim 1 wherein floatables are removed from the wet fraction in a dynamic cyclone.

3. The process of claim 1 wherein degritting is performed with a hydrocyclone.

4. The process of claim 1 wherein the wet fraction is diluted to 8-12% solids.

5. The process of claim 1 wherein the wet fraction is diluted with sludge.

6. The process of claim 1 wherein the wet fraction is co-digested with WWTP sludge.

7. The process of claim 1 wherein floatables are removed from the wet fraction.

8. The process of claim 1 wherein the solid waste is pressed at a pressure of at least 50 bar.

9. The process of claim 1 wherein the solids waste is pressed at a pressure sufficient to rupture cells in the organic material.

10. The process of claim 1 wherein the perforations have a size in the range of 4-10 mm.

11. The process of claim 1 wherein the wet fraction has a solids content of at least 20%.

12. The process of claim 1 wherein the solid waste comprises municipal solid waste and the wet fraction is at least 30% of the solid waste.

13. The process of claim 1 wherein the solid waste comprises source separated organics and the wet fraction is at least 70% of the solid waste.