AU5814500A

AU5814500A - Method and device for unloading and storing heterogeneous waste

Info

Publication number: AU5814500A
Application number: AU58145/00A
Authority: AU
Inventors: Gunter H Kiss
Original assignee: Thermoselect AG
Current assignee: Thermoselect AG
Priority date: 1999-06-22
Filing date: 2000-06-15
Publication date: 2001-01-09
Also published as: JP2003502247A; DE19928396A1; DE19928396C2; KR20020021135A; EP1196337A1; JP4455792B2; WO2000078643A1

Description

5 10 Method and device for unloading and storing heterogeneous waste The present invention relates to a method and a device for unloading and storing heterogeneous waste, such as refuse and the like, in waste bunkers in accordance 15 with the preamble of claims 1 and 17. Plants in which waste such as domestic and special waste, sewage sludge and industrial waste are thermally treated, have at their entrance waste bunkers in which largish amounts of this heterogeneous waste is 20 temporarily stored or kept in storage. These types of waste, which are here designated together as "refuse", represent in their very heterogeneous composition and in the usual storage amounts of thousands of tons a considerable environmental hazard.

2 Conventional waste bunkers must, therefore, be of sufficient dimensions that when refuse is poured from above into the waste bunker, there is always space for the latter inside the waste bunker. Conventional waste 5 bunkers comprise a large main bunker which lies with its bottom far below the surface of the ground and has a filling aperture at ground level. Thus refuse vehicles can drive at ground level backwards towards the aperture and empty the refuse into the waste 10 bunker. In particular as a result of driving the refuse vehicles to and from the aperture of the waste bunker, long unloading times arise and thus a low transfer capacity. Furthermore a discharge cone is formed, the 15 full height and the volume of the storage bunker only being used completely in the region of the aperture, whilst at the edges of the discharge cone large volumes of the waste bunker remain free. In order to utilise the storage volume present, the refuse then has to be 20 rearranged by means of an installed crane system. In order to simplify the bringing and unloading of the refuse into the waste bunker from the corresponding transport vehicles, such as for example lorries or railway wagons, traditional storage bunkers are placed 25 below the ground, such that it is possible to drive up at ground level to the filling aperture located at the top of the bunker. However this brings the disadvantage that the whole storage bunker has to be designed completely watertight because of the danger of 30 groundwater contamination. In the case of such large edifices this is naturally connected with very high costs. The purpose of the present invention is to quote an economical method and an economical device for 35 unloading and storing heterogeneous waste, in which the 3 capacity of the storage area is used in an optimum manner. This task is accomplished by the method according to the preamble of claim 1 and by the device according to 5 the preamble, of claim 17 in conjunction with their respective characterising features. Advantageous developments of the method according to the invention and the device according to the invention are quoted in the dependent claims. 10 According to the invention, the waste bunker is divided into a pre-bunker and a storage bunker, it being possible for the pre-bunker to be considerably smaller than the storage bunker. The storage bunker can be for example the main storage area of a refuse incineration 15 plant. The refuse is now tipped from a refuse vehicle through an aperture located behind it into an unloading area located before the pre-bunker. From there it is conveyed, for example by a ram, into the pre-bunker, 20 the bottom of which can be arranged at a lower level than the bottom of the unloading area. From the pre bunker, the refuse is then immediately transferred to the storage bunker. It is advantageous now that the refuse vehicles drive 25 forwards over the aperture, empty the refuse backwards into the unloading area and also leave the aperture in the unloaded state forwards again, such that high throughput is achieved. Since the waste is transferred immediately to the 30 storage bunker, only a small pre-bunker is required. Through the transfer of the waste, furthermore a discharge cone in the storage bunker is avoided such 4 that the storage capacity of the storage bunker is completely utilised. Advantageously, the waste is pushed out of the unloading area into the pre-bunker via an aperture, the 5 waste being so compacted as it is pushed that it forms in the aperture between the unloading area and the pre bunker a substantially gas-tight plug. Since the pre-bunker and the storage bunker are advantageously kept under an inert gas atmosphere and 10 under negative pressure, through the plug the penetration of external air into the pre-bunker and the storage bunker is prevented and thus the negative pressure guaranteed. Furthermore, through the compaction a volume reduction 15 in the waste is achieved already, such that the capacity of the storage bunker is utilised in an optimum manner. The aperture between the unloading area and the pre-bunker can be provided with a flap, the waste then being pushed in batches, for example by 20 means of a ram, from the unloading area into the pre bunker. The flap can be attached for example as a hanging or standing flap at the upper or respectively lower edge of the aperture so as to be rotatable. Advantageously, the flap is disposed on the aperture at 25 the side of the unloading area. The aperture can advantageously be configured as a horizontal shaft in which the waste is compacted and which is sealed in the manner of a plug by the compacted waste. in order to avoid any nuisance from odour in the 30 external region, the unloading area can itself have a charging hole which is configured as a funnel-shaped shaft or respectively has self-closing flaps which form a funnel-shaped shaft after opening. Furthermore, tne unloading area can be constantly exhausted by suction 5 in the region of its charging hole such that no dust or odour can penetrate into the external region. Advantageously, through the separation of the waste bunker into a pre-bunker and a storage bunker and 5 through the arrangement of an additional unloading area, it is merely necessary to dispose the pre-bunker and possibly the unloading area below the ground, the respective charging holes then being located at ground level. In this way, the unloading of the transport 10 vehicles driving up can take place at ground level. The storage bunker itself, which substantially serves to store the waste and can be separated from the pre bunker by a partition, can for its part be disposed above the earth, the crane raising the waste from the l5 pre-bunker into the storage bunker as it is transferred. This has the advantage that, admittedly the unloading of the arriving vehicles can take place at ground level as desired, however the largest part of the waste bunker in volume terms, namely the storage 20 bunker, can be added above the ground. Thus the storage bunker itself does not have to be constructed completely groundwater-tight and there is no danger of the ground around the storage bunker being contaminated by possible leakages, for example through penetrating 25 and out-flowing groundwater. Thus, in the construction of the waste bunker this produces an enormous saving in costs since only the pre-bunker or respectively the unloading area has to be arranged correspondingly sealed below the ground as in conventional waste 30 bunkers. Advantageously, the transport means, such as lorries or rail vehicles, drive over the closed unloading hatch of the unloading area as far as an unloading point, whereupon the transport means laden with waste is 35 weighed, the unloading hatch is then opened and the refuse is unloaded into this aperture, the loading

Claims

1. Method for unloading and storing heterogeneous waste, such as refuse and the like, in waste 5 bunkers (1) before its removal and possible subsequent thermal recovery or other further processing, characterised in that the waste is tipped from the transport means (19), 10 such as a lorry, container or the like, into an unloading area (11) arranged below a transport route (21), conveyed by means of a suitable device (14) to a pre-bunker (2) configured as part of the waste bunker, and then received by a crane system 15 (4) installed in the total waste bunker (1) and ,conveyed into a storage bunker (3) also configured as part of the waste bunker, from which storage bunker the waste can be removed for further processing and/or recycling. 20

2. Method according to the preceding claim, characterised in that the waste is compressed in the unloading area (11)

3. Method according to one of the preceding claims, characterised in that the waste is conveyed from 25 the unloading area (11) into a pre-bunker (2), the bottom of which is disposed at a lower level than the bottom of the unloading area (11).

4. Method according to one of the preceding claims, characterised in that the waste is pushed through 30 an aperture (15) between the unloading area (11) and the pre-bunker (2) into the pre-bunker (2), the waste being possibly previously compressed and further compacted as it is pushed, such that it is 12 substantially gas-impermeable in the aperture (15).

5. Method according to the preceding claim, characterised in that the waste is pushed in 5 batches between the unloading area (11) and the pre-bunker (2), through an aperture (15) provided with a flap (22, 23).

6. Method according to the preceding claim, characterised in that the flap (22, 23) closes 10 automatically after a batch of the waste has passed through it.

7. Method according to one of the preceding claims, characterised in that the waste is introduced from above into the unloading area (11), configured as 15 a storeroom, through an aperture (12) in the unloading area (11).

8. Method according to one of the preceding claims, characterised in that the waste is introduced into the unloading area (11) through an aperture (12), 20 designed as a funnel-shaped shaft, in the unloading area (11).

9. Method according to at least one of the two preceding claims, characterized in that the aperture (12) in the unloading area (11) is 25 provided with a, possibly self-closing, flap (13).

10. Method according to one of claims 2 to 7, characterised in that the waste is driven by transport means such as a lorry (19) or rail vehicles, as far as an unloading point (18) above 30 the aperture (12) into tne unloading area (11), the transport means (19) loaded with the waste is weighed, the aperture (12) in the unloading area 13 (11) is opened and the transport means (19) is unloaded into this aperture (12) and then weighed once more and the transport means leaves the unloading point (18), possibly in the previous 5 direction of travel.

11. Method according to the preceding claim, characterized in that, during unloading of the transport means (19), the unloading area (11) is exhausted by suction to prevent the development of 10 any dust and odour in the region of the aperture (12) in the unloading area (11).

12. Method according to at least one of claims 2 to 9, characterised in that the waste is stored under inert gas in the waste bunker (1) and/or in the 15 unloading area (11) in a substantially inert atmosphere to protect against the danger of fire.

13. Method according to tne preceding claim, characterised in that the inert gas flows through the waste (6). 20

14. Method according to one of the two preceding claims, characterized in that the pressure of the inert atmosphere is kept below the external atmospheric pressure.

15. Method according to one of the three preceding 25 claims, characterised in that nitrogen and/or carbon dioxide are/is used as the inert gas.

16. Method according to one of the preceding claims, characterised in that the waste (6) is discharged from the storage bunker (1), for example for 30 thermal recovery or other further processing, through sluices. 14

17. Device for storing heterogeneous waste such as refuse and the like, having a waste bunker (1) for storing the waste (6) before its removal and possible subsequent thermal recovery or other 5 further processing, characterised in that the waste bunker (1) has a pre-bunker (2) for interim storage of the waste and a storage bunker (3) for storing the waste (6) until it is removed, 10 and a conveying means (4) to transfer the waste from the pre-bunker (2) into the storage bunker (3), and in that an unloading area (11) is disposed before the pre-bunker (3) for off-loading the waste. 15

18. Device according to the preceding claim, characterized in that the conveying means (4) is a grab (4).

19. Device according to one of the preceding claims, characterised in that there is a wall (8) between 20 the pre-bunker (2) and the storage bunker (3).

20. Device according to one of claims 17 to 19, characterised in that the pre-bunker (2) is connected to the unloading area (11) via an aperture (11) 25

21. Device according to one of claims 17 to 20, characterised in that the bottom of the pre-bunker (2) is disposed at a lower level than the bottom of the unloading area (11).

22. Device according to one of claims 17 to 21, 30 characterised in that the unloading area (11) has a displacement and pressure means (14) for displacing the waste from the unloading area (11) 15 into the pre-bunker (2), applying such pressure to the waste that it is substantially gas-impermeable in the aperture (15).

23. Device according to one of claims 20 to 22, 5 characterised in that the unloading area (11) is a room with a filling aperture (12) at the top.

24. Device according to the preceding claim, characterised in that the filling aperture (12) is designed as a funnel-shaped shaft. 10

25. Device according to one of the two preceding claims, characterised in that the filling aperture (12) has a possibly self-closing closing means, for example a flap (13).

26. Device according to one of claims 17 to 25, 15 characterised in that the unloading area (11) and/or possibly the funnel-shaped shaft (12) can be exhausted by suction.

27. Device according to one of claims 22 to 26, characterized in that the displacement and 20 pressure means (14) is a ram (14) which is displaceable in the unloading area (11) in the direction of the aperture (15) towards the pre bunker (2).

28. Device according to one of claims 20 to 27, 25 characterised in that the aperture (15) between the unloading area (11) and the pre-bunker (2) is configured as a horizontal channel (15).

29. Device according to one of claims 20 to 28, characterised in that the aperture (15) between 30 the unloading area (11) and the pre-bunker (2) has 16 a possibly self-closing closing means, for example a flap (22).

30. Device according to one of claims 17 to 29, characterised in that the pre-bunker (2) and/or 5 the storage bunker (3) are/is filled with a substantially inert atmosphere.

31. Device according to one of claims 17 to 30, characterised in that the unloading area (11) and/or the pre-bunker (2) are disposed below the 10 ground and the storage bunker (3) at least partially above the ground.

32. Device according to one of the preceding claims, characterised in that the upper edge of the filling aperture (12) of the unloading area (11) 15 or possibly of the pre-bunker (2) is disposed approximately at ground level (20).