JPH09208975A - Conversion of common carbage into solid fuel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for converting common garbage into solid fuel, low in generation of toxic gas, enabling reuse of valuables in the garbage, capable of obtaining high-quality solid fuel in high efficiency at low cost by sorting reusable incombustibles from common garbage. SOLUTION: Feedstock 1a as common garbage is subjected to bag breakage in a primary crushing process 21, iron components are removed in a metal removing process 3, and the metal-removed feedstock is sieved in a sieving process 22. For the residual feedstock left on the sieve, glass bottles are recovered in a resource reclaiming/sorting process 29, and the remaining feedstock is subjected to aluminum sorting to remove incombustibles which are then reclaimed into resources again. The feedstock left on the sieve after removing the incombustibles is subjected to secondary crushing to sort HCl, source-contg. plastics. The garbage as feedstock passed through the sieve is incorporated with quicklime 24 in a mixing process 25, and the resultant garbage and the secondly crushed feedstock are dried and mutually mixed in a mixing process 26. The resultant mixed feedstock is subjected to volume reduction and solidification in a relevant process 27 and molded into the objective solid fuel 28.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing solid fuel from solid waste (hereinafter referred to as "general waste") generated from general households.

[0002]

2. Description of the Related Art Conventionally, as a technique for treating combustible wastes, for example, fixed fuels used as fuels for power generation have been manufactured from combustible wastes.

FIG. 4 is a process diagram showing an example of a conventional process for converting combustible waste into solid fuel. In FIG. 4, a raw material 1 made of combustible waste is crushed in a crushing step 2, magnetic separation is performed in a metal removing step 3, and dried in a drying step 4,
Next, in the volume reduction / solidification step 5, the raw material is reduced in volume and solidified, and the solid fuel 6 is obtained.

In the above process, in order to reduce the source of hydrogen chloride (HCl gas) contained in the manufactured solid fuel,
Usually, between the metal removing step 3 and the drying step 4, a predetermined additive 7 is added to the raw material to reduce the hydrogen chloride generation source (referred to as prior art 1).

As a technique for converting combustible waste into a fixed fuel, Japanese Patent Publication No. 62-8236 discloses a method and apparatus for producing fibrous substances and granular substances from waste (referred to as Prior Art 2). .

[0006]

However, the above-mentioned prior arts 1 and 2 have the following problems.

In Prior Art 1, in the crushing step 2, the entire amount of crushed material including garbage is crushed. However, general garbage contains 30 to 40% of garbage on a wet weight basis, and since the garbage contains about 30% of fine granules (about 20 to 30 mm), crushing is not necessary. Almost never.
Rather, a viscous substance such as leftover food acts as a kneading effect, and the substance stays on the blade of the crusher, causing a trouble due to clogging.

As described above, there is a big problem in the treatment of garbage, and it cannot be said that it is a solid fuel method suitable for general garbage containing a large amount of garbage.

[0009] In addition, although general garbage contains non-combustible components such as glass and metal, in the conventional method, the glass is turned into fuel without removing it, so that not only the calorific value of the generated fuel is lowered, There is a problem that it becomes impossible to reuse valuable resources.

Further, it is important to dry the solid fuel because it is important to increase the amount of heat generation in terms of quality as a fuel. That is, in order to increase the heat generation amount per wet weight of the solid fuel used as a product, it is necessary to dry and reduce the water content.

Further, the drying is an important factor in order to prevent the spoilage of the solid fuel stored for a long period of time, to prevent the generation of a bad odor, and to prevent the growth of microorganisms and mold.

Further, since only the metal component is removed from the combustible waste as a raw material by magnetic separation, when a hydrogen chloride generation source such as polyvinyl chloride (hereinafter referred to as PVC) is mixed in the raw material, It is inevitable that PVC or the like is mixed into the solid raw material. When PVC and the like are mixed in the solid raw material, hydrogen chloride is naturally generated and increased in the combustion process of the solid fuel used as a fuel, which causes generation and increase of dioxins. .

Further, in the prior art 1, since the whole amount of the crushed general waste including the incombustible component is dried by the dryer,
There are problems that the load of the dryer is large and the drying cost is extremely high, and that generation of high-concentration hydrogen chloride due to the PVC concentration present in general waste is unavoidable.

The prior art 2 also has the same problem as the above-mentioned prior art 1 regarding general dust.

The present invention has been made to solve the above problems, and by selecting reusable incombustible components from general waste, it is possible to obtain a solid fuel of excellent quality with high efficiency. Further, it is an object of the present invention to provide a method for converting general waste into a solid fuel, which enables reuse of valuable materials and generates less harmful gas.

[0016]

The invention according to claim 1 is a method for converting solid waste into solid fuel, which comprises the following steps (a) to (i).

(A) A primary crushing step in which general waste including garbage, paper, plastic, metal, etc. is taken out from a bag or the like and separated (b) A magnetic separation step in which iron is removed from the primary crushed general waste (c) Screening the remaining dust components from which irons have been removed into a sub-sieving component mainly consisting of garbage and a residual sieving component with a sieve. Step of sorting into heavy articles, medium-weight articles consisting mainly of aluminum (hereinafter abbreviated as "aluminum"), and light-weight articles consisting mainly of broken pieces of a plastic film bag (e) Step of sorting aluminum out of medium-weight articles ( F) Secondary crushing step for crushing medium-weight materials excluding aluminum (g) Step for selecting plastic containing hydrogen chloride generation source from secondary crushed medium-weight materials (h) Sieve mainly composed of garbage under Step of adding either quick lime or slaked lime to the components and mixing (i) Next, the mixture of the undersize component and quick lime or slaked lime, and the plastic containing the hydrogen chloride source are removed and secondly crushed Solid fuel molding process that mixes with heavy materials to dry, reduce volume, and solidify

The raw materials used in the method for producing solid fuel of the present invention are general garbage discharged from homes, and are mainly kitchen waste,
It is made of paper, plastic, metal, etc., and most are collected in garbage bags. In this case, the plastic includes a material such as PVC that becomes a hydrogen chloride generation source.

First, the trash bag is crushed by the primary crushing, the trash components in the bag are separated, and various containers, cardboard and other large sized dust are roughly crushed.

Next, in order to prevent mechanical damage to the equipment in the subsequent process, irons are removed and recovered by magnetic force selection by a magnetic force selector.

Then, sieving is carried out by using a rotary sieve or a vibrating sieve in order to separate mainly garbage in general refuse.

The sieve mesh at this time is set according to the grain size of the garbage, but in the case of general household waste, it is 20 mm or more,
It is suitable to set it in the range of 30 mm or less.

[0023] Quick lime or slaked lime is added to and mixed with the under-sieving component whose main ingredient is kitchen waste. The reason why quick lime or slaked lime is added and mixed is as follows. (A) The addition of quicklime or slaked lime increases the pH of the kitchen waste and prevents spoilage. (B) The added Ca content is taken into the solid fuel, and at the time of combustion, it reacts with the hydrogen chloride generation source contained in the solid fuel, for example, the Cl content due to PVC, thereby preventing the generation of hydrogen chloride. To do. (C) When quick lime is used, it reacts with the water content of the kitchen waste to reduce the water content.

On the other hand, the reason why the remaining on-screen components are selected by the difference in weight is as follows. This is because the remaining sieving components are mainly paper, plastic, glass bottles, aluminum cans, etc., so that the sieving components are used to select the glass bottles and aluminum cans.

This is because the non-combustible valuables in the glass bottle and the aluminum can can be reused and the non-combustible components in the produced solid fuel can be removed to obtain a good quality solid fuel.

After removing the valuables, the on-sieving component is secondarily crushed to a particle size almost equal to that of the above-mentioned sieve mesh. This is because it is desirable to adjust the particle size to be almost the same as that of the undersize component in order to mix it with the undersize component again to form a solid fuel in the next step.

Non-burnable valuables such as glass bottles and aluminum cans are sorted from the residual sieve, and secondary crushed paper and plastics are separated from the main component of hydrogen chloride, such as PVC, by the difference in specific gravity. For the reason.

By removing PVC or the like, the concentration of Cl content in the produced solid fuel can be reduced, a solid fuel with less hydrogen chloride generated by combustion can be obtained, and from the viewpoint of preventing hydrogen chloride generation. This is because it is possible to reduce the additive amount of Ca component to be added and to obtain a solid fuel with less generation of ash content.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a process chart for explaining the flow of the present invention. In FIG. 1, a raw material 1a made of general garbage including kitchen waste, paper, plastic and metal is stored by a pit crane 19 in the storage step, and the primary crushing step 2
In step 1, the bag is crushed by the primary crushing using a bag crusher, and is broken into pieces.

Next, the primary crushed raw material is subjected to magnetic force selection in the metal removal step 3 to remove irons which may damage the machine in the secondary crush.

When the amount of aluminum in the raw material is large, the aluminum in the raw material may be removed by performing aluminum sorting in the bypassed aluminum sorting step 12.

Next, in the sieving step 22, 20 to 30 mm
Vibrating or rotating sieve (Trommel sieve)
The raw material from which the metal has been removed is sieved using a rotary type sieving machine.

The sieve mesh can be changed according to the general waste of the raw material. For the raw material on the sieve, glass bottles are collected in a bottle sorting step 29a using a wind power sorting device in a resource sorting step 29, and aluminum is sorted in an aluminum sorting step 29b to remove incombustibles. The removed incombustibles are recycled.

For the raw material on the sieve after removing the incombustibles, a uniaxial shearing type crusher (uniaxial rotary blade type) of 20 to 30 mm was used in the secondary crushing step 23 to obtain a particle size equivalent to that of the sieve mesh. Secondary crushing is performed. Furthermore, the main PVC of the hydrogen chloride generation source is added to the secondary crushed on-sieving raw material by P
In the VC removal step 30, separation is performed by wet specific gravity separation.

On the other hand, in the mixing step 25, quicklime 24 is added to and mixed with the kitchen waste that is the raw material for sieving. The amount of quicklime added is preferably 5 to 10% of the dry weight of kitchen waste.

Slaked lime may be added instead of quick lime. Next, the raw material from which secondary crushing and PVC removal have been performed and the kitchen waste mixed with quick lime and mixed are dried and mixed in a drying / mixing step 26.

At the time of drying and mixing, hot air (or high temperature steam or the like) is blown at the same time as stirring to dry and adjust the water content.

Then, the mixed raw materials are reduced in volume / solidification step 2
At 7, the volume is reduced and solidified, and the solid fuel 28 is formed.

The reduction / solidification is performed by compressing and heating in a molding machine to melt the plastic component and mold / solidify it into a predetermined shape.

The above steps, namely (1) primary crushing step, (2)
Metal removal step, (3) sieving step, (4) recyclable material sorting step, (5) step of secondary crushing the remaining raw material selected from the recycleable material on the sieve, (6) secondary crushing A step of removing PVC or the like from the raw material (medium weight material) on the sieve,
(7) Raw material under sieve (sieved by sieving,
A process of adding quick lime or slaked lime to mainly kitchen waste) and mixing, (8) a process of mixing the products obtained through the above (6) and (7) to form a predetermined solid fuel (drying, volume reduction, solidification) It will be specifically described based on.

First, as a raw material for producing a solid fuel,
General garbage will be described. There are various kinds of combustible waste such as household, agriculture, forestry, organic industry and / or industrial waste, but in the present invention, general waste generated from household as a raw material is targeted.

The contents (composition) of general waste include kitchen waste such as leftover food, paper, plastic, wood, cloth, glass, metal (iron, iron,
Aluminum), earth and sand, etc. Further, bags made of vinyl or the like for collecting dust, cardboard boxes, etc. are also targets of dust.

There are areas where such general waste is separately collected according to composition, but the degree of its spread is still low.

Therefore, in the present invention, it must be assumed that all the contents are mixed in the general waste.

In the present embodiment, the compositional design values on the basis of wet weight are kitchen waste 30%, paper 40%, plastic 7%, wood and cloth 5%, glass 8%, metal (iron, aluminum) 4 %, Earth and sand and other 6%.

General garbage is usually collected in garbage bags. At home, kitchen garbage is drained in the kitchen, put in small bags, and then put into large bags together with other garbage at the garbage collection site. . Cardboard boxes are occasionally put out, but the number is small, and 99% of collecting means are large bags.

Next, (1) the primary crushing step will be described. The purpose of primary crushing is to crush the trash bag and take out the contents and disassemble them. In this step, a known bag breaking machine is used in order to suppress cracking of bottles.

Hereinafter, the primary crushing situation will be described according to the composition of general refuse. (A) About 98% of large and small garbage bags are broken. (B) The cardboard box is completely destroyed. (C) Cans pass with a degree of crushing. (D) Bottles pass without breaking and maintaining their shape. (E) A long object such as a tree may keep its shape depending on the posture when passing, or may be broken. (F) The cloth is only compressed and does not break.

Next, (2) metal removing step will be described. (A) Iron in the raw material is removed by known magnetic separation.

Next, the (3) sieving step will be described. The primary crushed raw material is subjected to sieving.

The purpose of sieving is to remove kitchen waste from the raw material to be subjected to secondary crushing. Kitchen waste is fine grain (20-30
(80 mm) occupies about 80%, so most of them do not require secondary crushing. Rather, for substances with viscosity such as leftover food, secondary crushing acts as a kneading effect, and this substance is It will stay on the blade of the next crusher and cause trouble due to clogging. Screened by sieving, i.e.
Under the sieve, in addition to kitchen waste, earth and sand and glass smaller than the sieve mesh are included.

On the other hand, materials that cannot be sieved, that is, on the sieve include paper, plastic, glass, wood, cloth (larger than the sieve mesh), metal (other than iron) and the like.

A vibrating screen or a rotary screen (Trommel screen) may be used for screening. Further, a vibrating sieve is effective when the throughput is less than 2 t / h, and a rotary sieve is effective when the throughput is more than that.

As for the shape of the mesh of the rotary sieve, a round shape rather than a square shape is less likely to be caught by plastic or cloth, and cleaning is easier. In the case of a square, it is easily clogged and is not suitable for mass processing. The sieve mesh is preferably in the range of 20 to 30 mm.
If the sieve mesh exceeds 30 mm, the amount of paper and plastic mixed under the sieve increases.

Table 1 shows typical examples of particle size distribution for each composition in the screening of raw materials after primary crushing.

[0057]

[Table 1]

From Table 1, as many kitchen wastes as possible were sieved,
It can be seen that in order to leave the others on the sieve, the sieve mesh is preferably in the range of 20 to 30 mm.

Next, the step (4) of recycle material selection step will be described. (A) A wind power sorter is used as a sorter using the difference in specific gravity.

(B) When a high-pressure jet type wind power sorter as shown in FIG. 2 is used as the wind power sorter, for example, a heavy object mainly consisting of glass bottles and aluminum cans, papers, wood, and plastic mainly It can be separated into heavy items and lightweight items mainly consisting of bags. In FIG. 2, the sieving raw material 1b is conveyed into the recycling sorting container 31 by the conveyer 30, dropped from the end of the conveyer 30, and air is dropped from the air injection nozzle 32 installed below the end of the conveyer 30. The sieving raw material 1b is sprayed, and the wind force thereof causes a heavy object and a medium object to be a heavy object chute 33 and a medium object heavy chute 3
Sort within 4. Light weight items are collected by the mesh screen 35. 36 is a compressor.

(C) Glass bottles classified as heavy items are collected and recycled.

(D) Almost all medium weight aluminum cans are beverage cans. By applying a known aluminum sorter,
Can be separated into aluminum cans and other combustible materials.
It is also possible to perform the above-mentioned metal removal step for aluminum sorting, but in order to improve the performance of the aluminum sorting machine, it is desirable to increase the component ratio of the aluminum in the sorting target, and it is performed after wind power sorting. The aluminum recovery rate is higher.

(E) Most of the light weight items are fragments of bags made of plastic film, and these bags are mostly polyethylene (PE) plastic, and these are recovered and recycled. Is possible. In addition, it is possible to increase the solid fuel conversion efficiency together with the medium weight material after aluminum removal, PVC removal, etc., through secondary crushing.

(F) If necessary, secondary magnetic force sorting may be performed before wind power sorting.

Next, the step (5) of secondly crushing the remaining raw material on the sieve (medium weight) from the raw material on the sieve by sieving will be described.

Secondary crushing is carried out on the raw materials (paper, plastic (mainly bottles), wood, cloth, etc.) remaining after sorting the resources (light and heavy) of the raw materials on the sieve by sieving. , Here, the particle size is adjusted.

Since the components to be subjected to the secondary crushing contain almost no garbage, metal, glass, etc., the load on the secondary crusher is reduced, and the problem due to the residual garbage does not occur. The blade is not damaged by glass, etc., and the secondary crushing is performed efficiently.

As the secondary crusher, a uniaxial rotary blade crusher equipped with a lower screen may be used. In addition, since the raw material after secondary crushing is mixed with kitchen waste again, by adjusting the secondary crushing particle size to the same size as that of kitchen waste, the quality of the solid fuel produced after drying, volume reduction and solidification in the subsequent process is good. It is because

Therefore, the blade width of the uniaxial shearing crusher is 20
~ 30mm range, lower screen screen mesh is 20-30
The dimensions are mm.

Next, (6) PV from the raw material selected from the raw material on the sieve as a medium weight product, aluminum removed, and secondarily crushed
The C removal step will be described.

A wet settling separator is used as a separating means using the difference in specific gravity. If a vertical swirl flow type sedimentation device as shown in FIG. 3 is used as the sedimentation device and water is used as the medium, polystyrene (P
S), PVC, polyethylene terephthalate (PET)
Is separated into a heavy specific gravity mainly composed of polypropylene and a light specific gravity mainly composed of polypropylene (PP) and polyethylene (PE) in the plastic.

In FIG. 3, the raw material 1c which has been sorted as a medium weight product in the resource sorting step and which has been aluminum-removed and secondarily crushed is conveyed to the stirring tank 38 by the sorting conveyor 37, and the raw material 1c is swept by the stirring blade 39. The raw material 1c is agitated in water, transported by the transfer pump 40 to the dispersion plate 42 at the center of the separation tank 41 together with water, and diffused in the separation tank 41. In the separation tank 41, a gentle swirl flow is formed by the water jet from the dispersion plate 42, and each raw material of the raw material 1c becomes a light specific gravity and a heavy specific gravity due to the difference in specific gravity with water. Floating sedimentation separation is performed, and each is discharged to the outside of the separation tank 41 by the swirling flow.

The discharged light specific gravity and heavy specific gravity are separated into water and solid through the vibrating screen 43 and collected.

PP, PE, and paper, wood, and cloth, which are recovered as light specific gravity, are made into solid fuel in the next process transition together with garbage as solid fuel. PS, PVC, and PET separated into heavy specific gravity are recovered, reduced in volume, and disposed (landfill).

Further, in order to increase the solid fuel conversion efficiency of plastic, a heavy liquid (specific gravity: about 1.2 g / cm ^{3 is} further added.
) May be used to separate and collect PVC to form solid fuel together with the PP and PE plastics that are separated and collected as light specific gravity.

The purpose of removing PVC and the like is to prevent as much as possible hydrogen chloride generated by reacting with Cl content during the burning of solid fuel. Further, by removing the hydrogen chloride generation source such as PVC in the solid fuel, the following effects also occur. By removing the hydrogen chloride generation source such as PVC in the fixed fuel, the addition of quick lime or slaked lime used for suppressing the generation of hydrogen chloride during combustion is reduced. Since less lime or slaked lime needs to be added, the ash content after combustion is low.

(7) Next, the processing of the kitchen waste that has been sieved by sieving and separated under the sieve will be described.

Quick lime (CaO) or slaked lime [Ca (OH) ₂ ] is added to the kitchen waste separated by sieving. It should be noted that the garbage includes soil separated under the sieve together with the garbage.

The effects of adding quick lime or slaked lime to kitchen waste are as follows (a) to (c).

(A) By adding quicklime or slaked lime,
The pH value of the kitchen waste is increased, and the protein in the kitchen waste is alkali-hydrolyzed and stabilized. Also, p suitable for microbial growth
Although the H value is less than pH9, the pH value of the garbage becomes higher than pH9, so that microbial growth during storage of the solid fuel produced as a product is prevented and spoilage is suppressed.

(B) The added quick lime reacts with the water in the garbage to reduce the water content. Evaporation of water is promoted by the chemical reaction between quicklime and kitchen waste and the heat of reaction, and quicklime 1
With the addition of kg, about 1 kg of water is removed from the kitchen waste.

For example, by adding 70% quicklime (ratio to the dry weight of kitchen waste) to 100 kg of kitchen waste having a water content of 70%, there is a drying effect of reducing the water content by 3%. In addition, 10% to 15% more than this is actually obtained by stirring and ventilation.
Has a drying effect.

(C) To prevent generation of hydrogen chloride during incineration of the solid fuel of the final product. When the solid fuel is burned, the Ca content added is the chlorine content in the solid fuel which is P from the plastic.
Since VC has been removed, food-related salts (NaCl)
It prevents the generation of HCl by reacting with the Cl component caused by the above.

The Ca content reacts with hydrogen chloride to form C
It becomes aCl ₂ (calcium chloride) and is recovered as ash or fly ash.

The amount of quicklime or slaked lime added to the kitchen waste is
The range is 1 to 20%, preferably 5 to 10%, based on the weight of the dried solid matter of the kitchen waste.

If the above-mentioned addition amount is less than 1%, the pH value is 9%.
The above is not satisfied (pH of kitchen waste ≧ 9), and the desired anti-corrosion effect cannot be obtained. Further, the dechlorination effect at the time of burning the solid fuel cannot be sufficiently obtained. On the other hand, when it exceeds 20%, the incineration residue due to the combustion of solid fuel increases too much.

Next, as (8) above (6) and (7)
The process (drying, volume reduction, solidification) of mixing the products that have undergone the processes and molding a predetermined solid fuel will be described.

Secondary crushed raw material of medium weight on sieve from which PVC and the like have been removed, mainly paper and plastic film,
And, the under-sieving raw material mainly consisting of kitchen waste mixed with quick lime or slaked lime is mixed in this step.

The undersize material and the above-size material have the same size,
It is crushed to ~ 30 mm, and the quality of the solid fuel produced in the subsequent process is good.

Finally, the mixed raw material is made into a solid fuel through a predetermined solid fuel forming step, that is, each processing step of drying, volume reduction and solidification.

[0091]

As described above, according to the present invention,
The following industrially useful effects are brought about.

Before the secondary crushing, sieving is performed to separate most of the kitchen waste from general waste. Therefore, in the secondary crusher,
It is possible to prevent a trouble caused by the kitchen waste being kneaded and attached to the inside of the apparatus.

The amount of dust treated by the secondary crusher is reduced, and the load on the secondary crusher can be reduced.

Since the garbage which has a particularly high water content in the general garbage can be separated and treated, it is possible to efficiently mix the additive for adjusting the pH and remove the water from the garbage.

By setting the mesh size of the sieving to 20 mm to 30 mm, the kitchen waste can be effectively separated from the domestic trash which is a general trash.

Iron, aluminum, and glass that cannot be made into fuel can be separately collected and recycled, and at the same time, a solid fuel containing no incombustibles can be produced, so that a high quality solid fuel having a high calorific value is produced.

Since the hydrogen chloride generation source such as PVC in the plastic is removed, the concentration of Cl in the finally molded solid fuel is low, and the concentration of hydrogen chloride generated during combustion can be reduced.

Further, it can be further reduced by adding an additive such as slaked lime. Since the Cl concentration in the solid fuel can be lowered, the amount of the additive for suppressing hydrogen chloride generated during combustion can be reduced. Also, the amount of ash after combustion is small.

[Brief description of drawings]

FIG. 1 is a process chart showing an embodiment of a solid fuel conversion process of the present invention.

FIG. 2 is a diagram showing an embodiment of a wind power sorter used in the present invention.

FIG. 3 is a diagram showing an embodiment of a wet sedimentation separation apparatus used in the present invention.

FIG. 4 is a process chart showing an example of a conventional solid fuel conversion process.

[Explanation of symbols]

 1 Raw Material 1a Raw Material from General Waste 1b Sieve Raw Material 1c Secondary Crushed Raw Material 4 Metal Removal Process 19 Pit Crane 21 Primary Crushing Process 22 Raw Material Sieving Process 23 Secondary Crushing Process 24 Quick Lime 25 Mixing process 26 Drying / mixing process 27 Volume reduction / solidification process 28 Solid fuel 12 Aluminum sorting process 29 Recycling sorting process 30 Conveyor 31 Recycling sorting container 32 Air injection nozzle 33 Heavy duty chute 34 Chute for medium weight 35 Mesh screen 36 Compressor 37 Sorting conveyor 38 Stirring tank 39 Stirring blade 40 Transfer pump 41 Separation tank 42 Separation plate 43 Vibrating sieve

Front Page Continuation (72) Inventor Yoichi Yoshinaga Marunouchi 1-2-2 Nihon Steel Pipe Co., Ltd., Chiyoda-ku, Tokyo (72) Inventor Mikihisa Asano Marunouchi 1-21-2 Marunouchi, Chiyoda-ku, Tokyo In the company

Claims (1)

[Claims] 1. A method for converting solid waste into solid fuel, which comprises the following steps (a) to (i): (A) A primary crushing process that removes general garbage containing garbage, paper, plastic, metal, etc. from the bag and separates it. (B) A magnetic separation process that removes iron from the primary crushed general garbage (c) Irons Screening the remaining dust components that have been removed into a sub-sieving component mainly consisting of garbage and a residual sieving component with a sieve. , A step of selecting a medium-weight item mainly made of aluminum and a light-weight item mainly made of a plastic film bag fragment (e) a step of selecting aluminum from a medium-weight item (f) a medium-weight item excluding aluminum Secondary crushing step of crushing (g) Step of selecting plastic containing hydrogen chloride generation source from the secondary crushed medium weight material (h) Quick lime or slaked lime as the under-sieving component mainly composed of the above-mentioned garbage (I) Next, mix the mixture of the undersize component and quick lime or slaked lime with the secondary crushed medium weight material from which the plastic containing the hydrogen chloride source has been removed. Solid fuel molding process of drying, volume reduction, and solidification