JP3938463B2 - Method and apparatus for separating and sorting incombustibles from municipal waste - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is based on municipal waste, which further separates and sorts combustible and non-combustible materials contained in tailing separated in the wind sorting process from municipal waste when producing solid fuel from waste such as municipal waste. The present invention relates to a method and apparatus for separating and sorting incombustible materials.
[0002]
[Prior art]
In recent years, the emission standards for trace hazardous substances such as dioxins in so-called municipal waste disposal have been strengthened, and the creation of a waste recycling society has been demanded. In recent years, attention has been focused on the solid fuel conversion of municipal waste that separates combustibles from municipal waste and uses it as solid fuel. As a solid fuel conversion technology for municipal waste, a basic process has already been established in which municipal solid waste is received and then solid fuel is produced through the steps of crushing, sorting, drying, and molding.
[0003]
For example, in Japanese Patent Laid-Open No. 7-150158, in a combustible material sorting and molding method for producing solid fuel from waste such as garbage and sludge, the waste containing bag is broken and the magnetic metal is removed. After primary crushing and drying the waste, it is placed in a closed container that forms a vertical updraft. Heavy incombustibles are allowed to settle, and light combustibles are collected along with the updraft. A method and apparatus for sorting and combusting combustible materials in waste to be formed after sorting combustible materials and further secondary crushing is disclosed.
[0004]
However, even in the combustible material sorting technology described in Japanese Patent Application Laid-Open No. 7-150158, the residue (tailing) separated and sorted by the internal circulation type wind sorter that forms a vertical updraft is mainly glass, Although it is made of non-combustible materials such as stone waste and non-ferrous waste, it is not limited to non-combustible materials, and it contains relatively heavy combustible materials. This is due to the fact that the moisture content varies depending on the type of garbage in the drying process, which is the pre-process of wind sorting. This is due to the type and properties of the garbage, such as the inclusion of a material with a large specific gravity or the combustible material adhering to the incombustible material. Even if garbage having such properties is inserted into the wind power sorter, there is a problem that combustibles are contained in the tailing.
[0005]
The tailing is about 1 to 3% by mass with respect to the whole municipal waste, and is landfilled at the final disposal site. However, when combustible materials are contained as described above, there is a problem of decay of combustible materials contained in tailing even at the final disposal site, and there is also a problem of generating unpleasant odors, which are contained in tailing. The amount of combustibles is also subject to regulation.
[0006]
[Problems to be solved by the invention]
In order to solve such problems, the present invention aims to further separate the combustible material from the tailing after the sorting of the wind power of the municipal waste, and to perform high-precision separation of the combustible material and the non-combustible material. Another object of the present invention is to develop an inexpensive device and provide a method for separating and sorting incombustible materials from municipal waste and a device therefor.
[0007]
[Means for Solving the Problems]
The present invention is a method for sorting tailings after sorting wind power from municipal waste into a horizontal water stream and selecting specific gravity, and separating and sorting combustible and incombustible materials, the flow rate of the horizontal water stream and tailing input A method for separating and sorting incombustible materials from municipal waste , wherein the distance from the position to the incombustible material sediment collection position is set according to the tailing characteristics . In the present invention, tailing is a residue separated from municipal waste by wind sorting, and means a relatively large specific gravity. Wind-powered tailing has low wind resistance and tends to settle, and most of it is non-combustible, but massive and heavy combustibles also sink and enter the tailing. In the present invention, the tailing is further separated into a combustible material and an incombustible material by separating the specific gravity with a water stream. The tailing after the municipal waste is dried and wind-sorted is small in volume with respect to the whole waste, has the characteristics that can be easily and accurately sorted by specific gravity sorting using water flow as a medium, and almost completely generates odors. Thus, the present invention has been completed.
[0008]
In the present invention, the flow rate of the horizontal water flow and the distance from the tailing charging position to the incombustible sediment settling position are set according to the tailing characteristics . The tailing characteristics may be obtained by a sedimentation test in which the sample is submerged in still water, and the relationship between these separations is determined by examining the separation and separation by horizontal water flow when the flow velocity and the distance are changed. Furthermore, it is also possible to determine an optimum set value according to the contents of tailing by trial and error.
[0009]
Further, in the above method prevents dense molded when solid fuel combustible materials after separation sorting good preferable Separating cotton waste combustibles in.
[0010]
Next, the apparatus of the present invention capable of suitably carrying out the present invention method provides a horizontal trough having a sedimentation portion in the middle of the passage, the water in the horizontal trough with a water amount adjustment device An apparatus for separating and sorting non-combustible materials from municipal waste, comprising: a water supply device; and a tailing supply device after sorting wind power from municipal waste in which the input position to the horizontal tub is variable.
[0011]
Furthermore, it is preferable to provide a wedge wire screen and a cotton dust collecting device, which enables separation with higher separation accuracy. A wedge wire screen is formed by arranging a number of wires with inverted trapezoidal cross-sections in parallel to form a slit in the direction of water flow, supplying water flow thereon, draining water, and sieving to contain solids contained in water above and below the slit. It is a fixed screen that separates things. The wedge wire screen has an advantage that cotton dust or the like is removed under the screen together with water without entangled the screen, while the screen upper surface is flat and the product on the screen can be easily conveyed and discharged by a scraper or the like. For example, the cotton dust collecting device may be a device in which a weir is provided at the upper end of a water storage tank provided below the wedge wire screen and is removed by accompanying the water overflowing from the weir.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a flow sheet of an embodiment of the present invention. The separation / separation apparatus of the present invention includes a tailing supply apparatus 1, a water supply apparatus 10, a separation apparatus 20, a combustible material collection apparatus 30, a cotton dust collection apparatus 40, and a setting apparatus 50.
[0013]
The tailing supply device 1 sends the tailing 2 including combustible matter discharged from the municipal waste from the wind power sorting process via the emergency return damper 3 to NO. 1 receiving conveyor 4 and NO. 2 Supply to the receiving conveyor 6. In an emergency, the damper 3 is switched and the tailing 2 is discharged. The supplied tailing 5 falls from the drop chute 7 into the horizontal basket 21 as a fallen object 8.
[0014]
The water supply apparatus 10 is as follows. The makeup water 11 is supplied to the circulation tank 12, supplied to the water supply tank 15 through the pipe 14 by the circulation pump 13, and supplied from the water supply tank 15 to the horizontal tank 21 through the control valve 18 and the water supply pipe 17. Excess water in the water supply tank 15 is returned to the circulation tank 12 through the overflow pipe 16.
[0015]
The separation device 20 includes a horizontal gutter 21 provided with a sedimentation separation unit 22 in the middle of the flow path. A thing with large specific gravity in the fallen object 8 supplied in the water flow settles in the sedimentation separation part 22 while moving by the horizontal water flow 27, and a thing with a small specific gravity is horizontally conveyed together with the water flow 27. The sediment 23 settled and separated in the sedimentation separation unit 22 is discharged as a waste 25 to a waste container 26 through a screw conveyor 24. This waste 25 has a combustible content close to zero, does not rot or emit odor, and has a smaller amount than the tailing 2 and is suitable for landfill disposal.
[0016]
The combustible material having a small specific gravity is accompanied by the horizontal water flow 27 and sent to the combustible material recovery device 30, and drained on the wedge wire screen 31. The drained combustible material is horizontally transported on the wedge wire screen 31 by the scraper 33 and discharged 34, recovered by the combustible material recovery conveyor 35, and returned to the waste pit as the recovered material 36.
[0017]
The separated water 32 enters the water storage tank 41. The cotton dust collecting device 40 is as follows. Among the combustibles that have fallen on the wedge wire screen 31 together with the horizontal water flow 27, fine cotton dust that has passed through the screen mesh together with water falls to the water storage tank 41 and floats on the water surface in the water storage tank 41. The floated cotton dust passes over the separation weir 44 provided on the side wall of the water storage tank 41 and falls to the adjacent mud tank 43 as an overflow 45. The cotton dust is accumulated in the sludge tank 43 as sludge and discharged from the lower part of the sludge tank 46 through the pipe 47 through the pipe 47. Further, the water from which the cotton waste is separated in the settling tank 41 is returned to the circulation tank 12 through the communication pipe 42 and reused.
[0018]
Furthermore, the following setting device 50 may be provided. The setting device 50 includes a setting device 51 for setting a water amount setting value 52 and a setting value 53 for the position of the dropping chute 7. The setting device 50 outputs these values and opens the water amount adjusting valve 18 and the position of the dropping chute 7. Adjust. This adjustment is determined according to the tailing characteristics. For example, among those included in tailing for wind sorting, non-combustible materials such as shells are unlikely to settle in water, combustible materials such as rubber are difficult to float, and combustible materials including plastics are likely to float. Therefore, it is necessary to select the sorting conditions according to the tailing characteristics.
[0019]
【Example】
Using the separation / separation device for non-combustible materials from municipal waste in the embodiment shown in FIG. 1, the daily amount of 0.3t (acceptance) discharged from the wind power sorting device during the solid fuel production process of municipal waste of 20t / day Sorting of tailing of 1.5% of waste). The processing speed of the separation / separation apparatus is 0.5 t / h, the supply amount of the supply water 5 is 0.3 to 0.8 m ³ / min, and the flow rate of the horizontal water stream flowing in the horizontal tank 21 is 0.3 to 1.2 m. / Variable in the range of seconds. The distance between the position of the tailing drop chute 7 and the settling separation part 22 was variable in the range of 0.2 to 0.6 m.
[0020]
By the test operation, the appropriate values of the horizontal water flow velocity and the position of the tailing drop chute 7 were obtained. Using the apparatus shown in FIG. 1, tailing after sorting wind power from municipal waste could be further separated into combustible and incombustible materials with high accuracy. 0.06 tons of incombustible material such as glass, stone waste, non-ferrous waste and the like with no combustible content was obtained. Using this apparatus, tailing after wind sorting could be reduced to about one-fifth, and at the same time, no bromide could be achieved.
[0021]
【The invention's effect】
According to the present invention, combustible and incombustible materials can be separated with high accuracy from tailing after sorting wind power from municipal waste, and the excellent effect of reducing waste volume and achieving malodor removal is achieved. .
[Brief description of the drawings]
FIG. 1 is a flow sheet of an example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Tailing supply apparatus 2 Tailing after wind power selection 3 Damper 4 1 receiving conveyor 5 tailing 6 supplied NO. 2 receiving conveyor 7 falling chute 8 falling object 10 water supply device 11 makeup water 12 circulation tank 13 circulation pump 14 piping 15 water supply tank 16 overflow piping 17 water supply pipe 18 control valve 20 separation device 21 horizontal trough 22 sedimentation separation unit 23 sediment 24 Screw conveyor 25 Waste 26 Waste container 27 Horizontal water flow 30 Combustible material recovery device 31 Wedge wire screen 32 Water 33 Scraper 34 Discharge 35 Combustible material recovery conveyor 36 Recovered material 40 Cotton dust recovery device 41 Water storage tank 42 Communication pipe 43 Waste mud Tank 44 Separation weir 45 Overflow 46 Waste mud pump 47 Piping 50 Setting device 51 Setting device 52 Water volume setting value 53 Setting value

Claims (3)

A method of sorting tailings after sorting wind power from municipal waste into a horizontal water stream and selecting specific gravity to separate and sort combustibles and non-combustibles. The non-combustibles from the flow rate of the horizontal water stream and the tailing input position A method for separating and sorting incombustible materials from municipal waste , wherein a distance to a settling collection position is set in accordance with the tailing characteristics . Horizontal dredging equipped with a sedimentation separation part in the middle of the flow path, water supply device equipped with a water amount adjusting device to supply water to the horizontal dredging, and wind sorting from municipal waste with variable input position to the horizontal dredging incombustible material separation sorting apparatus from city garbage characterized in that a tailing feeder after. The apparatus for separating and sorting non-combustible materials from municipal waste according to claim 2, further comprising a wedge wire screen and a cotton dust collecting device.

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