System for waste treatment

Abstract

A waste treatment unit. It comprises at least one gasifier having a main receptacle (1) with a waste inlet (2), a syngas outlet (6) and an ashtray outlet (8). In the interior of the receptacle there is a body (4) with at least one inclined section (7) disposed opposite to the waste inlet (2), and with a base (14) which creates a depletion shaft (17) that prevents the passage of waste; and a dividing wall (9a) in contact with said body (4) or an evacuation tube (9a) in the interior of the body (4), such as to create a waste zone (15) that encompasses at least the zone where the inclined section (7) is located, and a waste-free zone (16) wherethrough the syngas produced during oxidation of the waste flows towards the syngas outlet (6).

Claims

1. A waste treatment unit comprising: at least one gasifier having a main receptacle with a waste inlet disposed in the upper section of the receptacle, a syngas outlet and an ashtray outlet, wherein the gasifier comprises: a body comprising: at least one inclined surface, disposed in the interior of the receptacle, with the inclined surface disposed opposite to the waste inlet and a base disposed such as to generate a depletion shaft between said base and walls of the receptacle that prevents the passage of waste; a dividing wall disposed in the interior of the receptacle and in contact with the body, or an evacuation tube disposed in the interior of the body which comprises at least a first end corresponding to the syngas outlet and a second end disposed in the base of the body, the dividing wall or the evacuation tube separating a waste accumulation zone corresponding, at least, to said inclined surface and a waste-free zone wherethrough the syngas generated flows towards the outlet, such as to create a waste zone in the receptacle, that encompasses at least the zone wherein the inclined surface of the body is located and wherein the waste that enters through the waste inlet is accumulated, and a waste-free zone wherethrough the syngas produced during oxidation of the waste flows towards the syngas outlet, and heating means configured to heat the interior of the receptacle.

2. The waste treatment unit of claim 1, wherein when the waste treatment unit comprises an evacuation tube, the body has a concentric cone configuration.

3. The waste treatment unit of claim 1, wherein the heating means are disposed around the receptacle, are disposed in the interior of the receptacle or a combination of both.

4. The waste treatment unit of claim 1, wherein the heating means are disposed in the interior of the body.

5. The waste treatment unit of claim 4, wherein when the waste treatment unit comprises an evacuation tube, the heating means are disposed around the evacuation tube.

6. The waste treatment unit of claim 1, wherein the heating means are induction coils.

7. The waste treatment unit of claim 1, wherein the heating means comprise external heating means comprising a sleeve with an induction coil disposed around the receptacle.

8. The waste treatment unit of claim 7, wherein the external heating means extend from the waste inlet to the waste depletion shaft.

9. The waste treatment unit of claim 7 wherein the external heating means extend from the waste inlet to the ashtray outlet.

10. The waste treatment unit of claim 1, wherein the receptacle is cylindrical.

11. The waste treatment unit of claim 1, wherein when the waste treatment unit comprises a dividing wall, the body is an eccentric cone.

12. The waste treatment unit of claim 1, wherein the syngas outlet is disposed in the upper section of the receptacle.

13. The waste treatment unit of claim 1, wherein when the waste treatment unit comprises an evacuation tube, it comprises two waste inlets disposed diametrically opposite to each other in the upper section of the receptacle.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) As a complement to the present description, and for the purpose of helping to make the characteristics of the invention more readily understandable, in accordance with a preferred practical exemplary embodiment thereof, said description is accompanied by a set of drawings constituting an integral part of the same, which by way of illustration and not limitation represent the following:

(2) FIG. 1 shows a view wherein two embodiments of the gasifier can be observed, one in which it comprises a dividing wall and another in which it comprises an evacuation tube.

(3) FIG. 2A shows a cross-sectional view of the gasifier in the embodiment wherein it comprises a dividing wall.

(4) FIG. 2B shows a cross-sectional view of the gasifier in the embodiment wherein it comprises an evacuation tube.

(5) FIG. 3A shows a cross-sectional top view of the gasifier of FIG. 2A with waste in its interior and wherein the waste-free zone can be observed.

(6) FIG. 3B shows a cross-sectional top view of the gasifier of FIG. 2B with waste in its interior and wherein the waste-free zone can be observed.

(7) FIG. 4 shows a cross-sectional view of the gasifier in the embodiment wherein it comprises a dividing wall and the body has an eccentric cone configuration.

(8) FIG. 5 shows another cross-sectional view of the gasifier of the embodiment of FIG. 4 wherein the dividing wall can be observed.

(9) FIG. 6 shows a cross-sectional view of the gasifier in the embodiment wherein it comprises an evacuation tube and the body has a concentric cone configuration.

(10) FIG. 7 shows another sectional view of the gasifier of the embodiment of FIG. 5.

(11) FIGS. 8A-B show a cross-sectional elevation view and a cross-sectional top view of an exemplary embodiment wherein the gasifier comprises an evacuation tube and two waste inlets.

(12) FIGS. 9A-B show a schematic view of the gasification unit with a gasifier and reformer in an embodiment wherein the gasifier comprises a dividing wall and in an embodiment wherein the gasifier comprises an evacuation tube.

PREFERRED EMBODIMENT OF THE INVENTION

(13) What follows is a description, with the help of FIGS. 1 to 9, of exemplary embodiments of the present invention.

(14) The proposed gasification unit is of the type comprising at least one gasifier having a main receptacle (1) with a waste inlet (2) disposed in the upper section of the receptacle, a syngas outlet (6) and an ashtray outlet (8). The solid waste products are collected by the ashtray outlet (8). In FIG. 1, two possible embodiments of the gasifier of the invention can be observed.

(15) The waste is introduced in the gasifier through the corresponding waste inlet (2) and is heated in the interior of the receptacle (1) to trigger the corresponding chemical reactions that generate syngas and ashes as a result. An essential advantage of the present invention is that the gasifier is configured such that the syngas generated does not penetrate the waste as it circulates through the interior of the receptacle (1) towards the syngas outlet (6).

(16) In order to achieve said technical effect, the gasifier comprises, in the interior of the receptacle (1), a body (4) with at least one inclined surface (7). Both the body (4) and the inclined surface (7) can be clearly seen in FIG. 1. It can also be clearly seen in FIGS. 2A-2B, wherein the two possible embodiments of the gasifier can be observed in greater detail.

(17) The body (4) is positioned such that at least one inclined surface (7) is disposed opposite to the waste inlet (2). This allows the waste to fall on said inclined surface (7) of the body (4) disposed opposite to the waste inlet (2) as it is introduced.

(18) In the first embodiment, shown in FIG. 2A, the body (4) is preferably an eccentric cone-shaped body and, in the second embodiment, shown in FIG. 2B, it is preferably a concentric cone-shape body. In both cases, the body (4) comprises a base (14) disposed in such a manner as to generate a depletion shaft (17) between said base (14) and the walls of the receptacle (1) which prevents the passage of waste. This contributes to the accumulation of waste in the desired zones in the interior of the receptacle (1). The free space from the depletion shaft (17) to the ashtray outlet (8) is intended for the passage of the ashes generated during the oxidation of the waste in the interior of the receptacle (1).

(19) An essential technical characteristic of the gasifier is that it comprises, in the interior of the receptacle (1), an element that ensures that the syngas flows out through a zone free from waste and free from by-products that can contaminate it. In the first embodiment, said element is, as shown in FIG. 2A, a dividing wall (9a) which is in contact with the body (4). In this case, a cross-sectional view of the gasifier from the waste inlet (2) is shown. As can be seen, the dividing wall (9) is preferably disposed opposite to said waste inlet (2). In the second embodiment, the element that ensures the outflow of waste-free syngas is an evacuation tube (9b), which comprises a first end disposed corresponding to the syngas outlet (6) of the gasifier and a second end disposed in the base (14) of the revolution body (4).

(20) The essential advantage of the dividing wall (9a) and the evacuation tube (9b) is that they separate a waste zone (15) in the receptacle (1), which encompasses at least the zone wherein the inclined surface (7) of the body (4) is located and wherein the waste that enters through the waste inlet is accumulated, from a waste-free zone (16) wherethrough the syngas flows out of the receptacle (1). These waste zones (15) and waste-free zones (16) are clearly observed in FIGS. 3A-B.

(21) Preferably, in the first embodiment (shown in FIGS. 2A, 3A, 4 and 5) the length of the dividing wall (9a) is chosen based on the angle of repose on the inclined surface (7) of the body (4) of the waste to be treated. In FIG. 2A it can also be observed how the waste is retained in the depletion shaft (17).

(22) Likewise, the dividing wall (9a) creates a waste-free zone (16) wherethrough the syngas produced during oxidation of the waste flows towards the syngas outlet (6). Said waste-free zone (16) can be observed in FIG. 2B. Sealing by filling must be guaranteed such as to force the syngas to move through said waste-free zone (16).

(23) Preferably, as can be seen in the figures, in the first embodiment and, more specifically, when the body (4) is an eccentric cone-shaped body, the waste zone (15) encompasses the entire inclined surface (7) and part of the straight section of the body (4).

(24) FIGS. 4 and 5 show sections of the gasifier in the first embodiment. FIG. 4 shows a detailed view of the inclined surface (7) of the body (4) which is disposed opposite to the inlet (2). In this case, since the body (4) is an eccentric cone, there is only one inclined surface (7). FIG. 5 shows another cross-sectional view wherein the dividing wall (9a) can be clearly observed.

(25) In the second embodiment (shown in FIGS. 2B, 3B, 6, 7), since the revolution body (4) is preferably a concentric cone, the process geometry increases, i.e. the waste accumulation zone (15) around the revolution body (4) in contact with the inclined surfaces (7) increases with respect to the first embodiment. Likewise, since the evacuation tube (9b) is disposed in the interior of the revolution body (4), it does not occupy additional space in the interior of the receptacle (1). The length of the evacuation tube (9b) and the increase in the waste zone (15) are preferably determined based on the angle of repose on the inclined surfaces (7) of the body (4) of the waste to be treated.

(26) The interior of the evacuation tube (9b) is the waste-free zone (16) in the second embodiment. In this second embodiment, during the passage of the syngas through the evacuation tube (9b), energy exchange takes place with the waste in the interior of the receptacle (since it is in contact with the revolution body).

(27) FIGS. 6 and 7 show cross-sectional views of the gasifier in the second embodiment. FIG. 6 shows one of the inclined surfaces (7) of the body (4) disposed opposite to the waste inlet (2). FIG. 7, which represents another cross-sectional view of the same embodiment, shows the evacuation tube (9b) in the interior of the body (4), which connects the base (14) of the body (4) to the syngas outlet (6).

(28) FIGS. 8A-B show an example wherein a gasifier with an evacuation tube (9b) (second embodiment) comprises two waste inlets (2). As can be observed in FIG. 8A, the inlets (2) are preferably disposed on the upper part of the receptacle (1) and in opposite positions to one another. This makes it possible to increase the capacity of the gasifier of the waste treatment unit. This embodiment is possible because, since the body (4) is a concentric cone, it comprises various inclined surfaces (7) that guarantee the proper distribution of the waste in the interior of the receptacle (1), even if the waste is introduced from different positions. FIG. 8B shows how, even though there may be two waste inlets (2), the evacuation tube (9b) continues to be a waste-free zone (16).

(29) Additionally, in order to carry out the oxidation reactions of the waste in the receptacle (1), the gasifier further comprises heating means configured to heat the interior of said receptacle (1).

(30) FIGS. 9A-B show a waste treatment unit that further comprises a reformer (18). The reformer (18) is preferably connected to the syngas outlet (6) of the gasifier. The unit has been represented with the gasifier according to the first embodiment (FIG. 9A) and with the gasifier according to the second embodiment (FIG. 9B). As can be observed, the fact that the gasifier is of one type or another does not interfere with the operation/distribution of the other elements of the unit.

(31) In this case, a facility with a waste feeder (20) connected to the gasifier can be observed. The interior of the receptacle (1) of the gasifier has been represented with the body (4), the dividing wall (9) and a line that represents the accumulated waste. The path followed by the syngas through the interior of the receptacle (1) towards the syngas outlet (6) has been represented schematically to facilitate comprehension of the explanation provided. The connection of the ashtray outlet (8) to an ashtray (19) of the facility wherein the waste treatment unit is disposed is also shown.

(32) Since in this example the waste treatment unit further comprises a reformer (18), it can be observed how the syngas follows a path from the gasifier to said reformer (18), wherein the necessary reforming reactions to obtain a purer syngas outlet (21) than that obtained at the syngas outlet (6) of the gasifier take place. The reformer (18) also has an ashtray outlet (8) which, as can be observed in FIG. 5, is connected to an ashtray (19) of the facility.

(33) The heating means are disposed around the receptacle (1), are disposed in the interior of the receptacle (1) or a combination of both. FIG. 1 shows an embodiment wherein the heating means are internal heating means (5) disposed in the interior of the body (4), and external heating means (3), disposed around the receptacle (1).

(34) In a possible embodiment wherein there are external heating means (3), said external heating means (3) extend from the waste inlet (2) to the waste depletion shaft (17). This makes it possible to heat only the section of the receptacle (1) where the waste is located.

(35) In another exemplary embodiment, the external heating means (3) also extend along the ashtray outlet (8) to ensure the depletion of the carbonaceous waste and the eventual scorification of the ashes, if necessary.

(36) The external heating means (3) preferably comprise a sleeve wherein an induction coil which acts on the receptacle (1) wall is housed. The internal heating means (5) preferably comprise an induction coil housed in the interior of the body (4) such that they act on the walls thereof, transferring heat to the interior of the receptacle (1). This is the preferred combination of heating means because it ensures that an adequate temperature is maintained in any point of the interior of the receptacle (1).

(37) One of the technical characteristics of the gasifier, which gives it versatility, is that it can comprise different heating means. In a preferred exemplary embodiment, the heating means are induction coils because they enable instant start-up. In other exemplary embodiments, for example, electrical resistors or a combustion gas flow can be used.

(38) The unit can operate under a self-regulated stratification regime regulated simply by controlling the temperature of the desired zones of the heating means.

(39) The gasifier may further comprise, as observed, for example, in FIG. 1, at least one vapour injection inlet (10) for those cases wherein the waste has an insufficient amount of humidity, an emergency oxidising agent inlet (12) and an inertisation and emergency tripping unit (13). Likewise, the gasifier comprises the corresponding connections for controlling the pressure and temperature in the receptacle (1).

(40) Some of the modifiable parameters of the gasifier of the present invention are the height of the receptacle (1), the diameter of the body (4), the angle of inclination of the inclined surface (7) and the waste depletion shaft (17). Modifying these parameters enables the waste treatment unit to be adapted.