Pyrolytic waste treatment system

• US 5,868,085 A
• Filed: 04/28/1997
• Issued: 02/09/1999
• Est. Priority Date: 09/22/1994
• Status: Expired due to Term

• Current Assignee: Eastern Shore IP Holding LLC
• Original Assignee: Balboa Pacific Corporation
• Inventors: Hansen, Andrew H., Walker, William C
• Primary Examiner(s): Bennett, Henry A.
• Assistant Examiner(s): TINKER, SUSANNE CHRISTINE
• Application Number:
  US08/846,210
• Time in Patent Office: 652 Days
• Field of Search: 110/227-229, 110/346, 110/211, 110/257, 110/258, 110/238, 110/242, 110/110, 110/236, 202/118, 198/662, 198/620, 198/676
• US Class Current: 110/346
• 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: C10B 7/10 with conveyor-screws
• CPC Class Codes: Y02E 20/12 Heat utilisation in combustion or incineration of waste

Abstract

A system for pyrolysis of hydrocarbon constituents of waste material including a treatment unit featuring a retort with a ellipsoidal cross-section forming a first retort half and a second retort half, the material to be treated being selectively deposited in only one half of the retort at a time during any given period of system operation, to avoid abrasion and wear of the half not in use, thus effectively doubling the life of the retort component. Another feature of a treatment unit according to the invention is a heat reclamation arrangement that introduces gases that have first been combusted to supply heat energy to the retort through a conduit directly into the interior of the retort, to improve the efficiency with which pyrolysis takes place. Further, the treatment unit has an exhaust and cleaning arrangement to render gases produced during pyrolysis substantially free of pollutants such that the gases can be vented to the atmosphere. The exhaust and cleaning arrangement is characterized by a plurality of selectively detachable gas injection tubes, which provide fuel for thermal oxidation of the gases. Each injection tube can be removed for cleaning independently of any other injection tube, and removal can be accomplished without disrupting operation of the system. Still another feature of the treatment unit of the invention is the redundancy and high-temperature resistance of the seal between the retort and other components of the unit.

Claims

1. A treatment unit for pyrolyzing constituent elements of a starting material that are susceptible of pyrolysis, the unit comprising:

a pyrolysis chamber in which pyrolysis is to take place, said pyrolysis chamber having an input aperture through which starting material is introduced, and at least one output aperture through which the products of pyrolysis are discharged; and

a heating chamber in which heat energy is generated to initiate and sustain pyrolysis in said pyrolysis chamber, a first valve communicating with said heating chamber and a second internal valve disposed within said heating chamber, said heating chamber being in communication with the atmosphere via said first valve and being in communication with said pyrolysis chamber via said second internal valve.

2. A treatment unit as defined in claim 1 in which said heating chamber includes an exhaust port and in which said first valve is disposed within said exhaust port for opening and closing said exhaust port.

3. A treatment unit as defined in claim 2 in which said second valve is disposed internally of said heating chamber.

4. A method for pyrolyzing the hydrocarbon constituents of a starting material in a treatment unit, the treatment unit having a pyrolysis chamber in which pyrolysis takes place with an input aperture through which starting material is introduced and an output aperture through which the products of pyrolysis can be discharged, and a heating chamber in which heat energy is generated to initiate and sustain pyrolysis in the pyrolysis chamber, the heating chamber being selectively in communication with the pyrolysis chamber, the steps comprising:

combusting a fuel gas in the heating chamber to supply heat to the pyrolysis chamber;

conveying heat energy produced in the heating chamber into the pyrolysis chamber by conduction through the walls of the pyrolysis chamber;

conveying heat energy produced in the heating chamber directly into the pyrolysis chamber by opening a valve that is communication with the heating chamber and the pyrolysis chamber;

continuously introducing the starting material into the treatment unit at a selectable and controllable rate while preventing the entry of oxygen into the pyrolysis chamber;

pyrolyzing the hydrocarbon constituents in the starting material; and

removing the gaseous products and the solid residue produced by pyrolysis from the pyrolysis chamber.

5. A method for pyrolyzing material in a treatment unit, the treatment unit having a pyrolysis chamber in which pyrolysis takes place with an input aperture through which starting material is introduced and at least one output aperture through which the products of treatment can be discharged, and a heating chamber in when heat energy is generated to initiate and gassification in the pyrolysis chamber, the heating chamber being in communication with the pyrolysis chamber through a bivalve system, the method steps comprising:

combusting a fuel gas in the heating chamber to supply heat to the pyrolysis chamber;

conveying heat energy produced in the heating chamber into the pyrolysis chamber by conduction through the walls of the pyrolysis chamber;

conveying heat energy produced in the heating chamber directly into the pyrolysis chamber by closing a first valve which prevents the heat energy from escaping to the atmosphere and then opening a second valve which allows the heat energy to flow from the heating chamber into the pyrolysis chamber;

introducing the starting material into the treatment unit; and

pyrolyzing the starting material.

6. The method of claim 5, wherein said step of introducing the starting material further includes introducing the starting material continuously into the treatment unit at a selectable and controllable rate.

7. The method of claim 5, further including the step of preventing the entry of any significant amount of oxygen into the pyrolytic chamber.

8. The method of claim 5 further including the step of removing the gaseous products and the solid residue produced by pyrolysis from the pyrolysis chamber.