US3888632A

US3888632A - Combustion chamber

Info

Publication number: US3888632A
Application number: US424812A
Authority: US
Inventors: Jack J Fritz; Jr Theodore W Lucas
Original assignee: Andco Inc
Current assignee: Sofresid SA; Andco Inc
Priority date: 1973-12-14
Filing date: 1973-12-14
Publication date: 1975-06-10
Anticipated expiration: 1992-06-10

Abstract

Combustion apparatus comprising a chamber having a generally vertical cylindrical upper portion having a tangentially positioned inlet. The chamber has a generally funnel-shaped lower portion which receives liquid and solid products of combustion which are discharged from an outlet at the bottom thereof. A waste gas outlet is in the lower portion adjacent the bottom outlet. The flow of waste gas along the lower portion keeps the solid and liquid products in a molten or flowable condition, and this is enhanced by the shape and disposition of the lower portion.

Description

United States Patent Fritz et a1.

[ June 10, 1975 COMBUSTION CHAMBER Inventors: Jack J. Fritz, Buffalo; Theodore W.

Lucas, Jr., Williamsville, both of N.Y.

Assignee: Andco Incorporated, Buffalo, N.Y.

Filed: Dec. 14, 1973 Appl. No.: 424,812

U.S. Cl. 23/277 C; 110/8 A; llO/28 F Int. Cl F23c 9/04; F23g 7/06 Field of Search 23/277 C, 277 R; 55/461;

1lO/8 A, 28 F References Cited UNITED STATES PATENTS 2/1952 Doss 55/461 X 5/1954 Wagner 110/165 A 2,725,950 12/1955 Christiansen ..23/277C Primary Examiner.lames H. Tayman, Jr. Attorney, Agent, or Firm-Christel & Bean 5 7 ABSTRACT Combustion apparatus comprising a chamber having a generally vertical cylindrical upper portion having a tangentially positioned inlet. The chamber has a generally funnel-shaped lower portion which receives liquid and solid products of combustion which are discharged from an outlet at the bottom thereof. A waste gas outlet is in the lower portion adjacent the bottom outlet. The flow, of waste gas along the lower portion keeps the solid and liquid products in a molten or flowable condition, and this is enhanced by the shape and disposition of the lower portion.

10 Claims, 2 Drawing Figures PRIMARY COMBUSTION CHAMBER COMBUSTION CHAMBER BACKGROUND OF THE INVENTION This invention relates to slagging pyrolysis solid waste disposal systems, and more particularly to a new and improved combustion chamber for such systems.

In slagging pyrolysis solid waste disposal systems, waste material is charged into a primary combustion chamber wherein it is reduced to a slag which can be tapped from the chamber and to a gaseous product which is withdrawn from the primary chamber and conveyed to a secondary chamber wherein it is caused to burn to a completely oxidized condition so as to eliminate toxic and noxious gases and odors. A slag-like preduct also is removed from the bottom of the secondary chamber.

A problem encountered with the combustion chambers of such systems, particularly the secondary chamber, is a tendency of the slag material received at the chamber bottom to solidify or become non-flowing so as to block the chamber discharge outlet. This can impair the operation of the system, often requiring it to be shut down to remove the accumulation, and obviously is undesirable.

SUMMARY OF THE INVENTION It is, therefore, a primary object of this invention to provide a new and improved combustion chamber apparatus for the burning of gaseous material to a completely oxidized state.

It is a further object of this invention to provide such a combustion chamber apparatus which maintains the solid and liquid products of combustion received in the chamber in a molten or flowable state.

It is a further object of this invention to provide such a combustion chamber apparatus for use as a secondary combustion chamber in a slagging pyrolysis solid waste disposal system.

The present invention provides apparatus for effecting combustion of combustible material, especially gases, comprising a combustion chamber having an upper portion wherein combustion of the material occurs and a lower portion for receiving liquid and solid products of the combustion for discharge from the apparatus. Waste gas from the combustion flowing through the lower portion of the chamber is utilized according to the present invention to keep the liquid and solid products therein in a molten or flowing state to insure the complete removal thereof. This is accomplished by providing anoutlet for removal of the solid and liquid products adjacent the bottom of the chamber lower portion and a waste gas outlet adjacent the bottom outlet. The effect of waste gas flow on the liquid and solid products, including heating and a spiraling or whirling flow, is enhanced by the shape and disposition of the chamber lower portion.

The foregoing and additional advantages and characterizing features of the present invention will become apparent upon a reading of the ensuing detailed description together with the included drawing wherein:

BRIEF DESCRIPTION OF THE DRAWING FIGURES FIG. 1 is an elevational view, partly in section, with some parts broken away and others shown diagrammatically, ofa combustion chamber apparatus according to the present invention; and

FIG. 2 is a sectional view taken about on line 22 in FIG. 1.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT Referring now to FIG. 1, a primary combustion chamber is indicated diagrammatically at 10 and can be of the typeshown in US. Pat. No. 3,568,612 issued Mar. 9, 1971. Briefly, combustion chamber 10 would have an opening at the top into which waste materials can be charged for movement downwardly through the chamber. A hearth is located at the bottom of the chamber to which air at an elevated temperature and pressure is supplied so that the air moves upwardly in chamber 10. The air supplied to the hearth is at a temperature sufficient to cause combustion in chamber 10 not only for considerable burning of the waste material but also for melting of metal, glass and other solid materials so that they can move downwardly to the hearth in the form of a molten slag which is tapped therefrom in a suitable manner and upon cooling can be crushed and disposed of in a simple manner. Other primary chambers can be used.

The combustion in chamber 10, however, is incomplete and results in a combustible producers gas and vapors which are tapped from chamber 10 by a conduit 12 which leads to a secondary combustion chamber 16 constructed according to the present invention. Combustion chamber 16 comprises an outer shell 18 of steel or other suitable metal and an inner lining 20 of refractory material provided in a conventional manner. In preferred form the lining 20 comprises a combination of refractory brick and insulation material. Shell 18 and lining 20 are fabricated or otherwise formed to provide a generally cylindrical upper portion 22 of the combustion chamber which is closed at the top 24 thereof and which is disposed generally vertically in the position of use. Secondary chamber 16 is provided with inlet means 26 for introducing the material to be burned near the top of chamber 16. The outer shell 18 and inner refractory lining 20 can be fabricated in a manner providing inlet 26 which is cylinderical in shape as shown in further detail in FIG. 2 and which is connected to conduit 12 leading from primary combustion chamber 10.

A conduit 28'is connected to conduit 12 near the connection of the latter to chamber inlet 26 and is supplied with air from a fan 30. Fan 30 and conduit 28 supply any air which may be needed for complete combustion of the material conveyed in conduit 12. The supply of air can of course be controlled by controlling the operation of fan 30 and, in addition, conduit 28 may be provided with a control valve (not shown) therein. Thus mixingof the air from conduit 28 and the material to be burned from conduit 12 is provided before the material enters secondary combustion chamber 16.

The gaseous material supplied to chamber 16 through conduit 12 is very hot, having a temperature which may be sufficient to cause combustion when the material is mized with air from conduit 28. In order to insure ignition of the material, however, there is provided a burner or igniter means 32 in the path of the material after it is admixed with the secondary air from conduit 28 as shown in FIG. 2. Burner 32 can be of various suitable types well known to those skilled in the art and is positioned within the end of conduit 12 where it connects to inlet 26.

The combustion chamber 16 according to the presit invention also includes a lower portion designated i in FIG. 1 for receiving the liquid and solid products the combustion in chamber 16, such products comonly being referred to as slag. Lower portion 36 is in |mmunication with upper portion 22 and is defined by -ntinuing or extending wall portions of the outer shell i and inner refractory lining 20. These portions are bricated or otherwise formed to define lower portion i in a generally funnel-like shape or a generally coni- .l shape. In other words, portion 36 is hollow and has :onverging cross-section proceeding in a downstream rection, i.e., in the path of the gas flow through and lay from the upper portion 22. Furthermore, portion i is disposed with the longitudinal axis thereof extendg at an angle to the longitudinal axis of the cylindrical vper portion 22. As a result, portion 36 includes a first ner wall surface region or portion 40 which as shown FIG. 1 is disposed so as to be positioned in the path downward flow of gaseous material through the wer portion of the chamber 16 which flow is indi- .ted by the line 42. Thus the downward flow of gas ll] tend to contact or be incident on wall portion 40. )rtion 36 of chamber 36 includes another wall or surce portion 44 which with wall portion 40 defines the nnel-shaped region. Expressed differently, a plane lssing through surface 40 is disposed at a relatively rger angle to the longitudinal axis of the upper cylinical portion 22 as compared to the angle between a ane passing through surface 44 and that axis. The apparatus according to the present invention furer comprises first outlet means adjacent the bottom 'the lower portion 36 for removing the liquid and lid products of combustion i.e., the slag material. The ltlet means includes an opening generally designated 3 which is in communication with a conduit 50, the mnection between conduit 50 and the outer surface the chamber lower portion 36 being facilitated by eans of a reducer member 52. As shown in FIG. 1, the wnwardly inclined wall surface portion 40 leads to )ening 48, and conduit means 50 is disposed with the ngitudinal axis thereof generally parallel to but offset spaced from the longitudinal axis of the chamber )per portion 22. The apparatus of the present invention further comises second outlet means designated 56 in FIG. 1 for moving waste gas from the combustion. Outlet means passage 56 is located adjacent the outlet means 48, preferred form being positioned immediately next to adjacent the outlet 48 as shown in FIG. 1. The outlet lssage 56 is defined by extending portions of the outer ell 18 and refractory material 20. Outlet passage 56 'nnects to a conduit 60 for delivering the waste gas to suitable location for use or for further processing. 1e outlet means including passage 56 and conduit 60 disposed so as to cause an abrupt change in direction the flow of the waste gas. In particular, the inner surce 62 of the refractory material defining outlet pasge 56 meets surface 44 at a relatively sharp edge llCh approaches a right angle edge. In the position of e shown in FIG. 1, wherein the longitudinal axis of e cylindrical chamber 22 is disposed vertically, the 'mmon longitudinal axis of the outlet passage 56 and 'nduit 60 is disposed at an angle upwardly inclined lative to the horizontal, for example at about 45. The apparatus of the present invention operates in e following manner. The combustion within chamber 10, such as the pyrolysis of solid muncipal refuse, is incomplete, and a combustible producers gas and vapors, etc. are produced therein. This gaseous material is withdrawn from chamber 10 by conduit 12 which leads to the secondary combustion chamber 16 of the present invention. The apparatus 16 is positioned in use preferably so that the upper chamber portion 22 thereof is disposed generally vertically. Conduit 12 connects to inlet 26 near the top of the chamber 16 and in a tangential direction as shown in FIG. 2 whereby the gaseous material will swirl therein and tend to impringe against the refractory material 20 of the chamber. During the operation the apparatus, walls of the chamber are hot and promote burning of the material. Air needed for the complete combustion of the material conveyed in conduit 12 is supplied from conduit 28, and the movement of the material in and along the chamber 16 will further promote the admixing of the material and the air. The material burns in chamber 16, moving downwardly therealong in a spiral or whirling path through the upper portion 22 and then into and through the lower portion 36.

Solid and liquid products of the combustion, i.e., the slag material, are received in the lower portion 36, and the spiralling or whirling flow of the extremely hot gas flowing in the direction indicated by the arrows 42 serves to maintain the slag material in a flowable or molten state in the lower region 36. In particular, the disposition of surface 40 as shown in FIG. 1 is such that the slag-like material flows there along and is intimately contacted by or wiped by the extremely hot whirling gas which heats this material so as to maintain the molten or flowable state of the slag material thereby enhancing the flow along surface 40 downwardly through the outlet 48. Keeping the slag material, i.e., liquid and solid products of combustion, in a flowable or molten state in the lower portion of the apparatus 16 advantageously prevents accumulation or solidification which would otherwise tend to block the outlet 48. This, in turn, insures continued efficient operation of the apparatus and avoids the need to shut down the apparatus to remove solidified or non-flowing slag from the region of the discharge outlet. Waste gas products of the combustion leave the region of the lower chamber portion 36 through outlet passage 56 which, according to the present invention, is located adjacent, preferably immediately next to the slag discharge outlet 46. Thus, by having the extremely hot waste gas travel through or along the entire length of the lower chamber portion 36 which receives the slag or liquid and solid products of combustion, the hot gas is exposed to the slag material for the maximum amount of time possible. The shape of the lower chamber portion 36 which is generally funnel-like or frustro-conical and disposed in a manner such that inner wall surface portion 40 is positioned in the downward whirling or spiraling flow of gas promotes an intimate and effective contacting of the slag material by the hot gas. The slag material received in region 36 flows downwardly and along the downwardly inclined inner wall surface portion 40 to the outlet 48, and the material is contacted by the spiralling hot gas which keeps the material in a flowing condition. As shown in FIG. 1, preferably a major portion of the inner surface of the funnel-shaped portion 36 is positioned in or across the downward flow of hot gas. In addition, the foregoing is enhanced by the dispostion of outlet passage 56 and conduit 60 which cause an abrupt change in direction of the flow of the waste gas exiting therethrough.

The slag or mixture of liquid and solid products of combustion exits from the apparatus through a conduit 50 to a suitable storage or collection facility. The waste gas exits from the apparatus through conduit 60 whereupon it could be supplied to a waste heat boiler for the recovery of heat from the gas.

In the apparatus of the present invention there is a need to heat the conical region 36 for effective slagging operation. Region 36 is heated by radiation from combustion of the gaseous material in combustion chamber 16. In addition, the fact that the cross-sectional area of region 36 decreases in the direction of gas flow causes an increase in the velocity of the gases therethrough which, in turn, enhances their convection and radiation characteristics. Furthermore, the upward inclination of conduit 60 will cause any slag products resulting from auxillary combustion in conduit 60 to flow back downwardly to outlet 48.

The apparatus of the present invention thus adequately burns the gaseous products applied thereto and at the same time permits disposal of the noncombustible carry-over material in a molten or semimolten state which is flowable and does not interfer with operation of the apparatus. The pyrolysis or solid municipal refuse drives off hydrocarbons which provides a valuable source of low-grade fuel which has present therein long-chain hydrocarbons liquids which are difficult to burn, sold carbon particles, and noncombustible solids entrained in the gas flow. The combustion chamber 16 of the present invention adequately burns this fuel and provides maximum heat recovery, minimum emissions of particular material, a minimum amount of unburned carbonecous gases, and a disposal of the slag-like material in a flowable state which does not interfere with the operation of the apparatus. The apparatus of the present invention effects combustion of gases, tars and suspended particulate material in an efficient and effective manner.

Therefore, it is apparent that the present invention accomplishes its intended objects. While a single embodiment of the present invention has been described in detail, this is for the purpose of illustration, not limitation.

We claim:

1. Apparatus for effecting combustion of combustible material, especially gases, tars, and suspended particulate material comprising:

a. a combustion chamber having a generally cylindrical upper portion wherein combustion of said material occurs and a lower portion for receiving liquid and solid products of the combustion;

b. means for introducing the material to be burned into said chamber for flow therealong during combustion;

c. first outlet means in said lower portion adjacent the bottom thereof for removing the liquid and solid products of combustion, said first outlet means being offset from the longitudinal axis of said upper portion; and

d. second outlet means in said lower portion adjacent said first outlet means for removing waste gas from the combustion, said second outlet means being located to cause the waste gas to travel along the entire length of said lower portion, whereby said waste gas supplies heat to maintain said liquid and solid products in a flowable state in said lower portion of said combustion chamber to facilitate removal of said liquid and solid products through said first outlet means.

2. Apparatus according to claim 1, wherein said lower portion of said combustion chamber is generally funnel-shaped and disposed with the longitudinal axis thereof extending at an angle to the longitudinal axis of said cylindrical upper portion.

3. Apparatus according to claim 1, wherein said second outlet means comprises conduit means disposed so as to cause an abrupt change in direction of the flow of said waste gas.

4. Apparatus according to claim 1, wherein said first outlet means includes conduit means disposed with the longitudinal axis thereof disposed generally parallel to but offset from the longitudinal axis of said cylindrical upper portion.

5. Apparatus according to claim 1, wherein said upper portion of said chamber is disposed generally vertically thereby directing the flow of gas downwardly and wherein said lower portion is disposed so that a wall portion thereof leads to said first outlet means and is positioned in the path of downward flow of gas.

6. Apparatus according to claim 1, wherein said means for introducing material to be burned comprises a tangential inlet for causing a generally spiral or whirling flow along said upper and lower portions of said chamber.

7. Apparatus according to claim 1, wherein said upper portion of said chamber is disposed generally vertically so as to direct the flow of gas downwardly and wherein said lower portion is hollow and of converging cross-section in a direction from said upper portion to said first outlet means.

8. Apparatus according to claim 7, wherein the central axis of said lower portion is inclined and said first outlet means includes conduit means disposed with the longitudinal axis thereof disposed generally parallel to but offset from the central axis of said upper portion.

9. Apparatus according to claim 7, wherein said second outlet means comprises conduit means disposed with the longitudinal axis thereof inclined upwardly so as to cause an abrupt change in direction of the flow of said waste gas.

10. Apparatus according to claim 1, wherein said upper portion of said chamber is disposed generally vertically and said means for introducing material to be burned comprises a conduit entering near the upper end of said chamber so as to cause material to flow downwardly in a generally spiral path along said chamber, wherein said lower portion of said chamber is generally funnel-shaped and disposed so that a major portion of the inner surface thereof is positioned across the downward flow of gas, wherein said first outlet means is adjacent the bottom of said inner surface portion, and wherein said second outlet means is spaced from said inner surface portion.

Claims

1. APPARATUS FOR EFFECTING COMBUSTION OF COMBUSTIBLE MATERIAL, ESPECIALLY GASES, TARS, AND SUSPENDED PARTICULATE MATERIAL COMPRISING: A. A COMBUSTION CHAMBER HAVING A GENERALLY CYLINDRICAL UPPER PORTION WHEREIN COMBUSTION OF SAID MATERIAL OCCURS AND A LOWER PORTION FOR RECEIVING LIQUID AND SOLID PRODUCTS OF THE COMBUSTION; B. MEANS FOR INTRODUCING THE MATERIAL TO BE BURNED INTO SAID CHAMBER FOR FLOW THEREALONG DURING COMBUSTION; C. FIRST OUTLET MEANS IN SAID LOWER PORTION ADJACENT THE BOTTOM THEREOF FOR REMOVING THE LIQUID AND SOLID PRODUCTS OF COMBUSTION, SAID FIRST OUTLET MEANS BEING OFFSET FROM THE LONGITUDINAL AXIS OF SAID UPPER PORTION; AND D. SECOND OUTLET MEANS IN SAID LOWER PORTION ADJACENT SAID FIRST OUTLET MEANS FOR REMOVING WASTE GAS FROM THE COMBUSTION, SAID SECOND OUTLET MEANS BEING LOCATED TO CAUSE THE WASTE GAS TO TRAVEL ALONG THE ENTIRE LENGTH OF SAID LOWER PORTION, WHEREBY SAID WASTE GAS SUPPLIES HEAT TO MAINTAIN SAID LIQUID AND SOLID PRODUCTS IN A FLOWABLE STATE IN SAID LOWER PORTION OF SAID COMBUSTION CHAMBER TO FACILITATE REMOVAL OF SAID LIQUID AND SOLID PRODUCTS THROUGH SAID FIRST OUTLET MEANS.