JPH0762316B2 - Method for treating household waste, industrial waste and other similar wastes to produce cellulosic material - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to pre-milling of waste materials,
It relates to a method for magnetic separation, air-classification and fractionation, treating domestic waste, industrial waste and other similar wastes to produce cellulosic material.

[0002]

2. Description of the Related Art Such a method is disclosed in, for example, West German Patent No. 31 05 597, U.S. Pat. Nos. 4,623,515 and 4,
No. 815,668. Based on these prior arts, the basic principle of the present invention is to supply a light weight classifying material consisting of paper, woven and plastic materials separated in air classifying to a cleaning station and guide the cleaned air flotable material to a pulper After treatment with the pulper, the ballast substance is removed by a sieving operation (screening),
Cellulose particles suspended in water through a screen (screen) are directly or after being dehydrated by a press, a paper mill as a pulp (a paper mill can be associated with a treatment plant using the treatment method of the present invention. ) Or dry the cellulose particles dehydrated by a press to produce a powder.

In addition to this procedure, according to the treatment method of the present invention, another classified product can be separated in an excellent manner. Apart from recovering metals and minerals, this method of the present invention produces methane gas from readily decomposable refuse material, converts residual solids into agricultural products, and also non-decomposable energy-carrying materials. (Energy bearing materials)
And treating the material to form a material that can be stored and burned.

[0004] Today, the disposal of refuse (particularly household and commercial refuse, or some mix of factory waste) is a problem worldwide.
This problem can be divided into two main parts. A) effluent-free disposal, and b) recovery of recyclable components (some of which are useful).

Various methods of carrying out waste are known and are already in use, for example: combustion with energy, dumping with recovery of gas, compost and / or fuel. -Collection of individual components such as metal, glass, paper and horticultural waste, -collection of individual components by hand sorting with a picking belt, -manufacturing of suitable products A recycling system for producing fibrous and granular classified materials used as intermediate materials and / or additional materials (for example, West German Patent No. 31 05597,
See U.S. Pat. Nos. 4,623,515 and 4,815,668).

However, all of these disposal methods and technologies have the following drawbacks. That is, -the product quality is inferior, -the technical concept is incomplete, so that only a few drawbacks are solved, -a large amount of residue is generated, -energy cost and working cost are large. Therefore, it is uneconomical after all, and-excessively burdens the environment.

The waste sorted as described above is
Several systems are also known for partial use as secondary raw materials in special processes. This system applies in particular to separately collected waste paper or manually sorted waste paper. However, the conventional paper recycling system can only solve some of the problems and has the following drawbacks.

1. Since waste paper is highly contaminated with plastics, wood, textiles and other organic wastes, solid residues occur up to about 30% of the input (supply) of waste paper during pulp production. Nowadays, these ballast materials have to be discarded (discarded or burned) at great expense. Although these ballast materials contain a large amount of thermal energy, they must consume a large amount of energy to use the contained energy in order to be usable in the combustion zone. Alternatively, these ballast materials must be disposed of in a special dump site, where available energy is lost.

2. Contaminated slurries produce substances that are easily spoiled or galled from waste paper contaminated with vegetable and food waste. The solids in these contaminated slurries have a high energy content, but until now they had to be stored in special dumps or thermally treated and burned. Both of the above cases are costly and uneconomical.

The above opinion is that the previously known or available techniques for the disposal, recycling and utilization of waste materials can only solve a few of the many drawbacks. It clearly shows that there is.

[0011]

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a method and apparatus for converting unsorted domestic and industrial waste into other high quality products at the lowest cost and highest efficiency. To develop.

[0012]

In accordance with the present invention, waste is treated to produce an effective product such as: That is, -metal-> reprocessing -minerals -building industry -methane gas -agricultural products -fertilizers and carriers -solid fuels -electrical and thermal energy -internal use -cellulose powders -carriers and additives -paper pulp → Manufacture of paper and cardboard For mixed waste from households, the proportion of paper is 15 to 30% by weight even when collected separately.

According to the present invention, otherwise vulnerable cellulose is mechanically separated from the mixed waste and converted into a reusable product such as pulp or powder. Also, storable methane gas is produced from pollutants that are easily decomposed, and the residual solids are converted into agricultural products. In addition, non-decomposable energetic materials are processed into storable and combustible materials, minerals and metals being sorted and directed for reprocessing.

[0014]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Collected mixed waste leaving the home is discharged from the collection vehicle into the bin 1. The waste is mechanically transferred to step 2, the step of pre-milling with a shredder. The shredder loosens the waste and pre-mills it to a maximum size of about 20 x 30 cm.
An electromagnet 3 arranged above the conveyor device between the shredder 2 and the sorter 4 removes ferrous metal (metals containing iron) from the waste material stream. The ferrous metal sucked by the electromagnet is guided to the purification step 5 to remove contaminants from the scrap. The purified metal is guided to the process indicated by number 6, packed or filled in a container, and then subjected to an appropriate reprocessing operation. The pollutants separated in the purification step 5 are mainly organic substances and are carried to the bioreactor 19 and gasified.

The bioreactor 19 is a commercially available plant, and functions to convert volatile substances in the organic portion into gas and separate them from organic solid matter. These gases are processed as a storable combustion gas that can be transported in a container.
Is prepared and purified so that it can be marketed via. The solids from step 19 are directed to a sieving operation 21 where the solids are separated into two grades. The fine solids are processed into fertilizer products in step 22. The coarse solids, some of which have non-gasified energy carrier particles, are directed to mixing station 23, where they are mixed with the energy carriers from step 11 (step 4). Can also be mixed with the energy carrier from. This mixture is led to the press 24.
The press 24 is a commercially available device that dewaters the moist mixture under pressure to convert it into combustible briquettes.
This fuel may be supplied to the market via step 25, or a portion of it may be converted directly to the heat of the two-stage hot burner 26.

This heat can be supplied to the district heating device 27 and / or via step 28 to an internal supply device (eg pulp dryer 12). The ash from step 26 is either discarded via step 29 or further processed. The waste from which the ferrous metal has been removed is divided into two classified substances in the sorter 4. The heavier classifier separated here contains minerals and moist organic substances that cannot be air-floated, and is a water classifier.
Guided to 16. The moisture classifier 16 separates minerals and non-ferrous minerals from organic substances. The purified heavy material is separated in step 17 into non-ferrous metals and minerals and directed for further processing. The organic substance is guided to the settling tank 18 together with the water from the moisture classifier 16, and the settling tank 18 separates the organic substance from the water. The organic substance is the bioreactor 19 described above.
Water is returned to the moisture classifier 16 and the washing plant 7 (circulation).

The air-floating classified material is introduced into the cleaning plant 7 from the sorter 4. Alternatively, the air-floatable fraction (or part thereof) can be introduced into the mixer (mixing station) 23 via a bypass to influence the heat content and moisture contained in the fraction. it can.
The cleaning plant 7 functions to wash away the organic pollutants adhering to the air floatable substance. Organic pollutants are
It is led to the settling tank 18 together with the washing water. As already explained, the clean water is returned to the water classifier 16 and the washing plant 7.

The washed air-floatable substance, which is mainly all kinds of paper, textile and plastic materials, is introduced into the pulper 8. This pulper 8 is a commercially available device, and may be what is called a wet shredder or a pulping mill. In these devices (generally filled with hot water at 30-50 ° C.), the air-floatable substance is introduced with a very excess water (about 5: 95% water). Paper is crushed by the centrifugal effect of rotating water and crushed into fibers. When crushed to this extent, the pieces of paper contained in the air-floatable classify "melt" in this wet milling process into individual cellulose fibers. The pulp-fabric-plastic material mixture thus obtained is pumped to a sieving device 9. This sieving device 9 is an immersion type sieving device and separates pulp from the ballast material. The effluent from the sieving device 9 is led to the processing plant 30. Next, the purified water is returned to the pulper 8 and the organic slurry is guided to the bioreactor 19 described above.

The ballast material from the sieving device 9 is then separated from most of the water in the filter press 11 and introduced into the mixer 23 described above. Similarly, contaminated water is supplied to the settling tank 18 described above. The pulp taken out from the sieving device 9 is supplied to the press 10. The pulp is dehydrated by the press 10 to such an extent that water does not drip, so that the pulp can be transported to a paper mill by an ordinary truck. The water squeezed by the press 10 is also guided to the treatment plant 30 described above.

In parallel with this, the pressed pulp from the press 10 is directed to a drying / milling operation 12. Energy for this can be obtained from the internal supply devices 26, 28. The dry cellulosic powder is fed to the appropriate industry via step 14 as a high quality carrier or additive.
The papermaking steps 13, 14, 15 are preferably associated with the processing steps according to the invention. The effluent from the papermaking process can then be treated in the same manner as above via the treatment plant 30 or the settling tank 18 and also the pollutants which are treated together.
Cutting wastes and production wastes from the papermaking process can be returned and recycled.

[0021]

According to the processing method of the present invention, the following many advantages can be obtained. That is, 1. Cellulose can be recovered from the mixed waste without manual sorting. 2. The valuable materials present in the waste can be fully utilized.

3. Residues from the waste are negligible (up to 3% ash) and do not need to be dumped. 4. The processing method according to the invention requires minimal energy consumption. 5. High quality material is obtained. 6. The system of the present invention is independent of waste composition.

7. The processing method of the present invention is not tied to the market of individual products. 8. First, it is possible to produce agricultural products with a low content of harmful substances. 9. In the case of papermaking, the problem of discarding unprocessable substances can be solved (usually 30
% Is the substance that must be discarded). 10. The treatment method of the present invention can be used anywhere waste is generated.

[Brief description of drawings]

FIG. 1 is a flow chart showing a processing method of the present invention.

[Explanation of symbols]

 1 large box 2 shredder 3 electromagnet 4 sorter 5 purification process 6 iron scrap 7 cleaning plant 8 pulper 9 sieving device 10 pulp press 11 filter press 12 pulp dryer 13 paper mill 14 cellulose powder 15 paper / cardboard 16 moisture class device 17 mineral And non-ferrous substances 18 settler 19 bioreactor 20 methane gas 21 sieving device 22 agricultural products 23 mixer (mixing station) 24 press 25 fuel 26 high temperature burner 27 district heating device 28 heating device 29 ash 30 water treatment plant

Claims (5)

[Claims] 1. A method of premilling, magnetic separation, air classifying and classifying waste material to treat domestic waste, industrial waste and other similar wastes to produce cellulosic material, wherein the air The paper, the woven material and the light-weight classified material classified in the classification are guided to the cleaning station, the cleaned air-floatable material is guided to the pulper, and after treatment with the pulper, the ballast substance is removed by a sieving operation, A process for treating household waste, industrial waste and other similar wastes to produce a cellulosic material, characterized by drying the cellulose particles suspended in water through a sieve for further treatment. 2. The method of claim 1, wherein the cellulose particles are further processed in a paper mill. 3. The method according to claim 1, wherein the cellulose particles are separated and recovered as a powder. 4. The method according to claim 1, wherein easily degradable pollutants generated during the treatment step are collected and methane gas is generated in the bioreactor. 5. A substance which is not decomposed in the bioreactor is divided into two classification products by a sieving operation, the fine classification product is processed into a fertilizer product, and the coarse classification product is
5. If desired, the energy carrier generated in another step such as a sieving operation after treatment in a pulper is added, followed by dehydration in a press and conversion into a solid fuel. Method.