US3924548A

US3924548A - Incinerator

Info

Publication number: US3924548A
Application number: US418025A
Authority: US
Inventors: Chambon Michel G J Du
Original assignee: PEXIMAC BV
Current assignee: PEXIMAC BV
Priority date: 1972-11-24
Filing date: 1973-11-21
Publication date: 1975-12-09
Anticipated expiration: 1992-12-09
Also published as: DE2358071A1; GB1435307A; DK140191C; BE807694A; ATA981773A; NL7316054A; FR2208094B3; JPS4996574A; CA1003700A; CH577143A5; AT337335B; FR2208094A1; DK140191B

Abstract

Incinerator for incinerating houshold refuse or industrial waste wherein the combustion air is blown obliquely into the incinerator through a grate at such a pressure that the refuse mass is not only fluidised by said air flow but is also transported through the incinerator. The incinerator is particularly suitable to be mounted in a refuse-collecting van so that the collected waste can be immediately incinerated and the number of return trips to a dump can be reduced to a minimum.

Description

United States Patent 11 1 1111 3,

Du Chambon Dec. 9, 1975 [5 INCINERATOR 3,577,939 5/1971 Muirhead 110/8 3,589,313 6/1971 Smith et a1 110/8 [75] Inventor- 3,625,165 12/1971 Ishigaki 110/28 Versallles, France 3,702,595 11/1972 Muirhead et al.. 110/28 .1 7 A I v. P 3,745,940 7/1973 Hibbert 110/28 3] Sslgnee gggl The Hague? 3,773,00 11/1973 B0ttaliCO.... 110/18 3,774,555 ll/1973 Turner 110/8 [22] Filed: Nov. 21, 1973 Primary Examinerl(enneth W. Sprague [21] Appl' 4l8025 Attorney, Agent, or FirmMarn & Jangarathis [30] Foreign Application Priority Data [57] ABSTRACT Nov. 24, 1972 France 72.41800 Ineinerater for ineinerating houshold refuse or industrial waste wherein the combustion air is blown [52] US. Cl. 110/8 C; 110/8 A obliquely into the incinerator through a grate at such [51] Int. Cl. F23G 5/12 a pr sur hat the refuse mass is not only fluidised by [58] Field of Search 110/8 R, 8 C, 8 A, 28 J said air flow but is also transported through the incin- 110/7 R, 8 R, 18 R erator. The incinerator is particularly suitable to be mounted in a refuse-collecting van so that the col- [56] References Cited lected waste can be immediately incinerated and the UNITED STATES PATENTS number of return trips to a dump can be reduced to a 2,959,140 11/1960 Friedberg 110/8 x 4 3,289,617 Simpson 110/7 8 Claims, 3 Drawing Figures INCINERATOR This invention relates to an incinerator, in particular for incinerating household refuse and industrial waste.

In such incinerators, the quantity of products incinerated per unit area of fire-grate is proportional to the degree in which the products are agitated. Such agitation pulls the products apart, their useful heat exchange surface area is increased, and so is, to the same extent, the rate of combustion of these products. The rate of combustion is also a function of the rate at which air is brought into contact with the products. In known incinerators, the refuse is agitated mechanically, and as it is always difficult to operate a mechanical system satisfactorily under conditions of high and variable temperatures, these known constructions have never been quite satisfactory as regards operation and cost of maintenance. All this has also been conducive to bulky machines relative to the weight and volume that can be combusted per unit of time.

It is an object of the present invention to provide an incinerator in which the products are displaced without the incinerator being itself partly or entirely driven.

According to one aspect of the present invention, there is provided an incinerator for household refuse and industrial waste, comprising a combustion chamber having a grate, means for supplying combustion air, and filling and discharge means, characterized in that the combustion air, which is blown through said grate, is used for lifting the load of refuse being treated in the incinerator, whereby said load is torn apart, and brought into a fluidized state, and in which, owing to a pre-determined orientation of the air, effected by said grate, the combustion air also serves for transporting the material through the incinerator.

Thus the incinerator according to the invention is so arranged that the combustion air flows through adapted grates under a pressure sufficient to carry and transport the products through the incinerator and to separate the various elements of the products from one another, thereby to maximize their heat exchange surface area. The grates are mounted in the interior of the incinerator in various ways, depending on the process phase and their position in terms of their functions in such process phase. The local rate of flow, pressure and temperature of the combustion air also differ in dependence on the position in the combustion system.

Some embodiments of the invention will now be described, by way of example, with reference to the accompanying diagrammatic drawings, in which FIG. 1 is a cross-section of an incinerator according to the invention;

FIG. 2 is a cross-section of another embodiment of the incinerator of FIG. 2; and

FIG. 3 shows a refuse collecting van incorporating an incinerator as shown in FIGS. 1 or 2.

Referring to the drawings, an incinerator 1 is subdivided into three

combustion zones

2, 3 and 4. Each of these zones is equipped with a

wind box

5, 6 and 7, respectively, bounded by

grates

8, 9 and 10, respectively, having openings ll, 12 and 13, respectively, with deflecting members disposed at an angle. A blower l4 forces air under pressure and at a pre-determined rate of flow through

conduits

15, 16 and 17 to

boxes

5, 6 and 7. This air reaches

zones

2, 3 and 4 between the inclined deflecting members at a pressure sufficient to lift the refuse present in these zones, and for blowing the component elements of the refuse apart. In this way the refuse is brought into a fluidized state. Owing to the orientation of the deflecting

members defining openings

11, 12 and 13, the refuse is not only lifted, but also displaced by the air from the inlet of the incinerator to the outlet thereof, and this at a rate corresponding to the residence time of the refuse in each zone. The air which has flown through the refuse is laden with combustion gas and is discharged through a discharging, purifying and dust separating device of a known kind. In this discharge path, the air passes

boxes

18, 19, 20, 21, 22, 23 and 24, in which the combustion gases are subjected to secondary combustion. These boxes surround furnace l and

wind boxes

5, 6 and 7, as a consequence of which the air flowing through these is pre-heated before reaching

zones

2, 3 and 4. The circulation of air (mixed with combustion gas) in boxes 18-24 is controlled by means of

valves

25, 26, 27 and 28. The refuse materials are ignited in the furnace by means of

burners

29 and 30, which are ignited and extinguished under the control of known control means. The secondary combustion of the combustion gas can be initiated or boosted by means of burners 31 and 32, which are put into and out of operation by known control means.

In each zone the rate of flow and the pressure of the air, the number and dimensions of the openings and the orientation of the deflecting members are set in dependence upon the combustion phase of the refuse to be combusted in the zone concerned. In zone 2 the refuse is dried, pre-heated and ignited, in zone 3 the material is combusted, and in zone 4 the combustion is completed, and in this zone the material is converted into ashes.

The refuse is introduced into the furnace through a lock 33 of a known per se kind. The ashes fall into a channel 34 by gravity whence they are introduced into a reservoir (not shown).

In certain cases it may be of advantage to prepare the material prior to introducing it into the incinerator by subjecting it to tearing and crushing operations.

In the modification shown in FIG. 2, the furnace has three chambers mounted one on top of the other, and each corresponding with a combustion zone.

The grates, formed with openings and deflecting members, can be constructed in the form of a mosaic of elements placed side by side with expansion joints between them. These elements may have the form of corrugated sheets.

The incinerator according to the invention can be constructed of light, metallic elements (thin, profiled sheet steel), which permits a large variation in size. Such an incinerator can be the basic element of both a mobile unit and a large-capacity incinerator plant. The apparatus according to the invention also lends itself extremely well for an incinerator unit at the end of a pneumatic household-refuse chute.

FIG. 3 shows a refuse-collecting van accommodating an incinerator according to FIGS. 1 or 2. Such a van has the advantage that, since the refuse is combusted as it is collected in the streets, it is much less frequently necessary to travel to a dump to discharge the material collected. 5

I claim:

1. An incinerator for household refuse, industrial waste, and like material, comprising a combustion chamber having a stationary grate means, means for supplying combustion air through said grate means, and filling and discharge means, characterized in that said grate means includes deflecting members for directing said combustion air in a manner to lift said material being treated in the incinerator whereby said material is torn apart and brought into a fluidized state, and whereby owing to a pre-determined orientation of the air effected by said grate means, the combustion air also serves to transport said material through said incmerator.

2. Apparatus according to claim 1, wherein the furnace is divided into a plurality of combustion zones, each zone having a supply of air of different rate of flow, pressure and temperature, and each zone having grate openings and deflecting means adapted to the function of such zone.

3. Apparatus according to claim 1 wherein the furnace and at least part of said means for supplying combustion air is surrounded by secondary combustion chambers for the secondary combustion of a combustion gas withdrawn from said furnace so that said combustion air is preheated through heat exchange between said secondary combustion chambers and said means for supplying combustion air.

4. Apparatus according to claim 3, wherein the gas circulation in said secondary-combustion chambers is controlled by valves.

5. Apparatus according to claim 2 wherein said combustion zones are located one behind the other, and said furnace is tunnel-shaped.

6. Apparatus according to claim 2 wherein the cornbustion zones are located one above the other.

7. Apparatus according to claim 1 characterized by means in said filling means for comminuting the refuse.

8. A refuse-collecting van provided with an incinerator as claimed in claim 1.

Claims

1. An incinerator for household refuse, industrial waste, and like material, comprising a combustion chamber having a stationary grate means, means for supplying combuStion air through said grate means, and filling and discharge means, characterized in that said grate means includes deflecting members for directing said combustion air in a manner to lift said material being treated in the incinerator whereby said material is torn apart and brought into a fluidized state, and whereby owing to a pre-determined orientation of the air effected by said grate means, the combustion air also serves to transport said material through said incinerator.

3. Apparatus according to claim 1 wherein the furnace and at least part of said means for supplying combustion air is surrounded by secondary combustion chambers for the secondary combustion of a combustion gas withdrawn from said furnace so that said combustion air is pre-heated through heat exchange between said secondary combustion chambers and said means for supplying combustion air.

6. Apparatus according to claim 2 wherein the combustion zones are located one above the other.

8. A refuse-collecting van provided with an incinerator as claimed in claim 1.