US3807323A

US3807323A - Refuse burner apparatus

Info

Publication number: US3807323A
Application number: US00339337A
Authority: US
Inventors: R Watts
Original assignee: Individual
Current assignee: Koppers Inc
Priority date: 1973-03-08
Filing date: 1973-03-08
Publication date: 1974-04-30
Anticipated expiration: 1991-04-30

Abstract

A subterranean burning chamber for burning refuse, which is covered by a frusto-conical metal shell, comprises a steel structure that is refractory lined and has hollow walls that are fluid-cooled. Means is provided for maintaining the chamber in place when buoyant forces are present.

Description

0 United States Patent 1 91 1111 3,807,323

Watts Apr. 30, 1974 REFUSE BURNER APPARATUS 3,483,832 12/1969 B011 et al. .1 110/7 [76] Inventor: Ralph E. watts, 1313 Sewanee Dr. 3,452,690 7/1969 Tarbox et al. ll0/7 Florence 2950] Primary ExaminerKenneth W. Sprague [22] Filed: Mar. 8, 1973 Attorney, Agent, or FirmSherman H. Barber; Olin E. [21] Appl No 339 337 Williams; 0scar B. Brumback 52 us. 01. 110/8, 110/18 R [57] BSIRACT 51 1m. 01. F23g 5/00 A Subterranean buming chamber for burning refuse, [58] Fi ld f S h 110 7 R, 3 R, 8 C, 1 R, which is covered by a frusto-conical metal shell, com- 1 10/13 C prises a steel structure that is refractory lined and has hollow walls that are fluid-cooled. Means is provided [56] References Cit d for maintaining the chamber in place when buoyant UNITED STATES PATENTS forces are present 3,704,676 12/1972 Davies et al. 1. 110/8 5 Claims, 6 Drawing Figures ffl //.9/ /97 0 //9 O i V95 i-fj iHHHHWHHH REFUSE BURNER APPARATUS BRIEF SUMMARY OF THE INVENTION A refuse burner, in accordance with the present invention, includes a subterranean, open-topped pit or chamber, that has hollow, fluid-cooled structural walls, the lower part of which are encased in concrete. The top of the pit or chamber is covered by a frusto-conical shell with means at the top for collecting effluent given off by burning material in the pit or chamber. Such effluent is recirculated into the bottom of the pit or chamber.

For a further understanding of the invention and for features and advantages thereof, reference may be made to the following description and the drawing which illustrates a preferred embodiment of equipment in accordance with the invention which is suitable for practicing the method of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a schematic vertical sectional view of apparatus in accordance with one embodiment of the present invention;

FIG. 2 is a plan view of the lower portion of the apparatus of FIG. 1;

FIG. 3 is a view along line lII-III of FIG. 4;

FIG. 4 is a view along line lV-IV of FIG. 3;

FIG. 5 is a view of the top portion of the apparatus shown in FIG. 1; and

FIG. 6 is a view along line VI--VI of FIG. 5.

DETAILED DESCRIPTION Referring to FIG. 1, a refuse burner 111, in accordance with one embodiment of the present invention, comprises a frusto-conical shell 113 that surrounds and is located above a subterranean pit or burning chamber is generally rectangular in shape; is open topped; and is substantially entirely subterranean except for a small portion at the top that extends a short distance above ground level. Such pit or burning chamber 125 is constructed in the manner shown generally in FIGS. l-4.

The frusto-conical shell 1 13 includes an angle iron or structural steel skeleton frame 115 that is covered, preferably, with aluminized sheet steel shell 117. The skeleton frame may, of course, be made of any other structural members as preferred. Both the frame 115 and the shell 117 are supported upon a circular concrete footing 119 disposed at ground level 121. The frusto-conical shell 113 is disposed above and surrounding the subterranean pit or burning chamber 125.

The top of the frusto-conical shell 113 is shown in FIG. 5 and includes a cylindrical-shaped tubular member 123 wherein there is a conventional damper 124. The damper 124 may be of the vane or the shutter type, and it may be controlled in a conventional manner by a device that responds to the temperature of effluent from burning waste products in the pit or burning chamber 125, or it may be operated manually, as preferred.

The pit or burning chamber 125 has four vertical side walls that are formed of outer 127 and inner 129 membranes, such as steel plating or heavy gauge sheet steel. These outer 127 and inner 129 membranes are maintained in spaced-apart parallel relation by a plurality of vertically arranged structural beams, such as I-I-beams 131. Each of the I-I-beams 131 is provided with a plurality of holes 133 in its web for a purpose that will be explained hereinafter.

The outer plating or membrane 127 is supported by vertically spaced-apart, horizontally arranged I-beams and by short intercostal sections of vertically arranged structural angles 137. The wall membranes or plating 127, 129 and the l-I-beams 131 are capped by a horizontal cap plate 139, and they are supported upon a steel base plate 141. Thus, the wall structure is hollow and fluid-tight, and the holes 133 provide a passageway through the structural H-beams 131 for the flow of fluid, which may be air, in the wall structure to cool it.

The inner surface of the inner membrane or plating 129 is covered with an insulating material 143 that may be mineral wool or any other suitable insulating material. Continguous with the insulating material 143 is a lining of refractory bricks 145.

The bottom of the burning pit or chamber 125 is a resilient substance, such as a layer of sand 147, disposed over the bottom plating 141. In the sand layer 147 there are a plurality of grate boxes 149 that are each provided with top grate 150. Each grate box 149 is connected to a riser 151 extending through the bottom plating 141 and joining a conduit 153 below the bottom of the pit or burning chamber 125.

The lower one-third portion of the wall structure and the bottom of the pit or burning chamber 125 are encased in concrete 155. The concrete 155 acts to prevent the hollow, bouyant wall structure of the pit or burning chamber 125 from moving upwardly whenever sub-surface water is present in sufficient quantity to exert a bouyant force on the chamber 125. Anchor bolts 157 connect the side walls to the concrete, as shown. Of course, other means than concrete may be used, if preferred, to provide enough extra weight in the structure to counteract bouyancy effects of subsurface water and the like on the chamber 125. Further, in regions where sub-surface bouyancy is not a consideration, the concrete 155 may be omitted, but yet, in most instances, it may be installed to provide a more rigid support for the pit or burning chamber 125.

Associated with the pit or burning chamber 125 is a fly ash reinjection system and a fluid-cooling system for the wall structure of the chamber 125.

The fly ash reinjection system includes a collector cone 159, shown in FIG. 5, that is located just below the cylindrical-shaped tubular member 123 at the top of the frusto-conical shell 113.

The collector cone 159, however, has a conical outer shell 161 that merges with a conduit 163 at its top, the conduit 163 being disposed horizontally, as shown, through the shell 113, and directed downwardly outside the shell, as suggested. The collector cone 159 has a bottom portion 165, shown in FIG. 6, that is comprised of a structural grid 167 made up of angles 169 to which are applied concentric annular plates 171, so arranged that there are annular spaces 173 between adjacent concentric annular plates; a center plate 175 is provided that is not annular in shape.

Conduit 163 connects with a centrifugal type fan 177, that is provided with suitable motor drive 179, situated on a concrete slab or base 181 adjacent the pit or burning chamber 125, as suggested in FIG. 2. A discharge conduit 183 from the fan 177 connects to the header conduit 153 (FIG. 1) with which the risers 151 and grate boxes 149 are associated, as mentioned previously.

On the foundation or concrete slab 181, there is another fan 185, preferably of the centrifugal type, having a suitable motor drive 187, that receives ambient air through an intake 189 and that discharges the air under pressure into a plenum 191 through conduit 193. The plenum 191 communicates, as shown in FIG. 1, with the hollow wall structure, supplying cooling fluid thereto.

The cooling fluid circulates through the hollow wall structure and then discharges to atmosphere through an exhaust conduit 195; such conduit may also pass through the shell 1 13 and terminate outside thereof, as preferred.

Associated with the wall structure and the plenum 191 are a plurality of nozzles 197 that extend slightly into the pit or burning chamber 125 and at a downward angle, about as shown in FIG. 1.

In operation, a quantity of wood and paper are placed on the floor of the pit or burning chamber, and they are ignited in a suitable conventional manner. A damper 46 at the top of the shell 113 is closed initially and the fly ash reinjection system is activated to circulate the effluent arising from the burning wood and paper. The effluent is recirculated back into the chamber and, thereby, does not escape to pollute the atmosphere.

The apparatus is quickly brought up to a working temperature as additional waste wood products and other combustible material are introduced into the pit or burning chamber, as desired, through a chute 45, as suggested in FIG. 1.

When the chamber is at the working temperature and the walls have become heated, the cooling air fan is turned on to circulate cooling fluid in the space 199 between the inner and outer walls. The cooling fluid maintains the walls of the pit or chamber relatively cool, and during the burning process, waste wood and other combustible material are introduced, more or less continually, into the chamber through the chute. In some instances a vehicle carrying such combustible material, may be admitted vto the shell, through an opening therein, (not shown) in order to dump its load into the chamber.

From time to time, or whenever it is deemed necessary or desirable, mobile equipment, such as a backhoe or other similar apparatus, may be admitted to the shell through the opening for the purpose of removing ash residue from the chamber. Such apparatus can easily approach close enough to the edge of the chamber to quickly and effectively remove the ash residue.

Those skilled in the art will recognize that when the walls of the chamber have reached a desired temperature, the fan, which connects to the nozzles within the chamber, is operated. Air jetting from such nozzles creates a curtain over the burning material and,'together with the fly ash recirculating system, develops very high temperatures within the chamber. The temperature, about 2,000F, is well above that generally regarded as desirable, which is around 800F, to obtain complete and effective burning of waste material and the effluent produced.

From the foregoing description of one embodiment of the invention, those skilled in the art should recognize many important features and advantages of it, among which the following are particularly significant:

Very high combustion temperatures, as high as about 2,000F, are obtained in the combustion zone of the chamber of the apparatus of the invention. Since a temperature of only about 800F will produce clean burning of waste wood products, it is readily apparent that, at the high temperature achieved in the apparatus of the invention, no smoke or effluent escapes to the atmosphere;

Because the temperature in the subterranean chamber may be as high as 2,000F, the refractory-lined walls, with insulating space in which fluid such as air under pressure circulates, can better withstand such a high temperature than the thin shell portion above ground;

Because the distance between the combustion zone in the chamber and the collection cone in the present apparatus is greater than that of burner apparatus known from the prior art, the fly ash cools down somewhat, and the upward, thermally-generated velocity of the fly ash in the present apparatus is much lower than that developed in prior art burner apparatus. These advantages result in less wearing of the conduits of the present fly ash reinjection system;

That batch feeding of waste wood products and other consumable material into the chamber is readily afforded, since there is a large access door and opening in the shell of the apparatus;

That ash removal from the chamber can also be readily accomplished, since mobile ash removal equipment is easily moved into and out of the shell through the access door and opening;

Since almost the entire burning chamber is below ground level, a uniform temperature profile down the wall of the chamber is effected, and no thermal shocks are set up from water or wind, and the like, or from any water seepage below ground level.

Flooding of the burning chamber is prevented, since it is protected by the above-ground shell;

The structural characteristics of the burning chamber, particularly the fluid-cooled walls andthe resilient sand floor, promote long life in service with very little loss in burning time or expense; and

The resilient floor in the chamber absorbs highimpact loads from batch feeding of large items such as pole cut-offs, stumps, scrap wood, and the like; the sand floor also is an effective insulating medium to prevent spalling of the concrete base.

Although the invention has been described herein with a certain degree of particularity, it is understood that the present disclosure has been made only as an example, and that the scope of the invention is defined by what is hereinafter claimed.

What is claimed is:

1. In a refuse burner apparatus, the improvement comprising:

a. a hollow wall structure comprised of inner and outer spaced-apart plates with structural members disposed therebetween to maintain such plates in place, said wall structure being substantially entirely below ground level;

b. a layer of insulating material disposed on the inner wall plate;

c. a layer of refractory material convering said insulating layer andforming the inner surface of the walls of said burner apparatus;

d. a cap plate covering the top of said wall structure;

e. a bottom plate on which said walls rest thereby forming a support for said structure and the bottom of said apparatus;

f. a plenum chamber communicating with said hollow wall structure for introducing fluid thereinto to cool said wall structure;

g. means for introducing a cooling fluid into said plenum chamber; and

h. means for flowing said cooling fluid out of said wall structure.

2. The invention of claim 1 including:

a. a frusto-conical shell surrounding and covering the burning apparatus and having therein:

b. a collector for effluent emitted by burning refuse in said apparatus, said collector being located adjacent the top of said shell,

c. said collector comprising a grid that has spaces through which said effluent passes; and

d. conduit means connecting said collector and a fan that receives such effluent and urges it into and through grate boxes in said bottom plate.

3. In a refuse burner apparatus, the improvement comprising:

a. a hollow wall structure comprised of spaced-apart inner and outer membranes forming the periphery of said apparatus with means therebetween for maintaining said membranes in spaced-apart relation, said wall structure being substantially entirely below ground level;

b. a cap plate covering the top of said wall structure;

c. a bottom plate on which said walls rest thereby forming a support for said structure and a bottom closure for said burner apparatus; and

d. means coacting with said wall structure for resisting upward forces acting on said apparatus.

4. The invention of claim 3 wherein:

a. said means coacting with said wall structure comprises a jacket of concrete affixed to said wall structure.

5. The invention of claim 3 including:

a. a plenum communicating with said hollow wall structure for introducing a cooling fluid into said wall structure; and

b. means for introducing a cooling fluid into said plenum.

2733 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,807,323 D d April 30, 1974 Inventor(s) Ralph E. Watts It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

? The name and address of the Assignee should be printed on the face of the patent as shown below:

Assignee: Koppers Company, Inc.

a Corporation of Delaware Signed and sealed this lsti day of October 1974,

(SEAL) 'Attest:

McCOY M. GIBSON JR. c. MARSHALL DANN Attesting Officer Commissioner of Patents

Claims

1. In a refuse burner apparatus, the improvement comprising: a. a hollow wall structure comprised of inner and outer spacedapart plates with structural members disposed therebetween to maintain such plates in place, said wall structure being substantially entirely below ground level; b. a layer of insulating material disposed on the inner wall plate; c. a layer of refractory material convering said insulating layer and forming the inner surface of the walls of said burner apparatus; d. a cap plate covering the top of said wall structure; e. a bottom plate on which said walls rest thereby forming a support for said structure and the bottom of said apparatus; f. a plenum chamber communicating with said hollow wall structure for introducing fluid thereinto to cool said wall structure; g. means for introducing a cooling fluid into said plenum chamber; and h. means for flowing said cooling fluid out of said wall structure.

2. The invention of claim 1 including: a. a frusto-conical shell surrounding and covering the burning apparatus and having therein: b. a collector for effluent emitted by burning refuse in said apparatus, said collector being located adjacent the top of said shell, c. said collector comprising a grid that has spaces through which said effluent passes; and d. conduit means connecting said collector and a fan that receives such effluent and urges it into and through grate boxes in said bottom plate.

3. In a refuse burner apparatus, the improvement comprising: a. a hollow wall structure comprised of spaced-apart inner and outer membranes forming the periphery of said apparatus with means therebetween for maintaining said membranes in spaced-apart relation, said wall structure being substantially entirely below ground level; b. a cap plate covering the top of said wall structure; c. a bottom plate on which said walls rest thereby forming a support for said structure and a bottom closure for said burner apparatus; and d. means coacting with said wall structure for resisting upward forces acting on said apparatus.

4. The invention of claim 3 wherein: a. said means coacting with said wall structure comprises a jacket of concrete affixed to said wall structure.

5. The invention of claim 3 including: a. a plenum communicating with said hollow wall structure for introducing a cooling fluid into said wall structure; and b. means for introducing a cooling fluid into said plenum.