Municipal solid waste disposal process

• US 5,280,757 A
• Filed: 08/13/1992
• Issued: 01/25/1994
• Est. Priority Date: 04/13/1992
• Status: Expired due to Term

• Current Assignee: Resorption Canada, Ltd.
• Original Assignee: Andreas Tsangaris, George W. Carter
• Inventors: Tsangaris, Andreas, Carter, George W.
• Primary Examiner(s): Favors, Edward G.
• Application Number:
  US07/930,020
• Time in Patent Office: 530 Days
• Field of Search: 110/346, 110/250, 588/227, 48/203, 48/209, 48/210
• US Class Current: 110/346
• CPC Class Codes: C01B 7/191 Hydrogen fluoride
• CPC Class Codes: C03B 5/005 of glass-forming waste materials disposal or transformation of solid waste in general B09B; treatment of radioactive waste G21F9/00
• CPC Class Codes: C03B 5/025 by arc discharge or plasma heating
• CPC Class Codes: C03C 1/002 Use of waste materials, e.g. slags
• CPC Class Codes: C04B 18/026 Melted materials C04B14/22 takes precedence
• CPC Class Codes: C04B 32/005 Artificial stone obtained by melting at least part of the composition, e.g. metal C04B28/36 and C03C take precedence; cast stone from molten slag C04B5/00; artificial stone obtained by melting the polymeric ingredient of the composition C04B26/00
• CPC Class Codes: C10B 19/00 Heating of coke ovens by electrical means
• CPC Class Codes: C10B 53/00 Destructive distillation, specially adapted for particular solid raw materials or solid raw materials in special form wet carbonising of peat C10F
• CPC Class Codes: C10J 2200/12 Electrodes present in the gasifier
• CPC Class Codes: C10J 2300/0946 Waste, e.g. MSW, tires, glass, tar sand, peat, paper, lignite, oil shale
• CPC Class Codes: C10J 2300/1238 by plasma
• CPC Class Codes: C10J 2300/1631 Ash recycling
• CPC Class Codes: C10J 3/10 using external heating
• CPC Class Codes: C10K 1/026 by centrifugal forces cyclones B04C
• CPC Class Codes: C10K 1/101 with water only
• CPC Class Codes: F23G 2204/201 Plasma
• CPC Class Codes: F23G 5/085 High-temperature heating means, e.g. plasma, for partly melting the waste

Abstract

A plasma arc torch is used as an independent heat source in an enclosed reactor vessel to gasify municipal solid waste and produce a medium quality gas and an inert monolithic slag having substantially lower toxic element leachability. The gas has lower levels of metals and semi-volatile organic compounds, particularly dioxins and furans. Other materials may also be gasified, for example, coal, wood and peat.

Claims

1. A process for gasification of municipal solid waste (MSW) and other carbon based solids, comprising the steps of:

(i) igniting a plasma arc torch inside a refractory lined reactor vessel;

(ii) preheating said reactor vessel walls to substantially 1100 C or more; and

(iii) feeding said MSW into said reactor vessel while minimizing entry of air.

2. A process for gasification of a mixture of municipal solid waster (MSW) and other carbon based solids, comprising the steps of:

(i) igniting a plasma arc torch and creating a vertical heating zone inside a refractory lined reactor vessel;

(ii) preheating said reactor vessel walls to substantially 1100°

celsius or more; and

(iii) feeding said MSW directly into a side portion of said vertical heating zone in said reactor vessel, while minimizing entry of air.

3. The process for gasification of MSW as defined in claim 2, wherein said MSW remains in said vertical heating zone to cause moisture in said MSW to react with said carbon-based solids and to substantially remove said carbon-based solids from said mixture.

4. The process for gasification of MSW as defined in claim 3, wherein said MSW is fed into said reactor vessel by means of a horizontal hydraulic feeder.

5. The process for gasification of MSW as defined in claim 3, wherein product gas is extracted from said reactor vessel at a location which is spaced from the side of said reactor vessel through which MSW is fed.

6. The process for gasification of MSW as defined in claim 5, wherein said MSW is pyrolyzed to form gas and monolithic liquid slag.

7. The process for gasification of MSW as defined in claim 6, wherein said gas which is formed by pyrolysis is exhausted from said gas reactor vessel by means of a cyclone.

8. The process for gasification of MSW as defined in claim 7, wherein said monolithic liquid slag is a silicate mass, which, when cooled, encapsulates any metal compounds and metals which were present in said MSW.