JP2954990B2 - Method of manufacturing solid fuel from waste - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial application field) The present invention treats waste such as garbage discharged from, for example, ordinary households or business establishments, so that it can be reused as fuel. The present invention relates to a method for producing a solid fuel by using waste.

(Prior art) Conventionally, waste such as refuse discharged from, for example, ordinary households or business establishments has been increasing more and more in recent years, and disposal of this waste has been a problem in any industrialized country. That is the current situation.

Conventionally, this waste is roughly divided into combustible waste and non-combustible waste, and the combustible waste is transported to a waste disposal site for disposal, and the non-combustible waste is crushed and converted into combustible, incombustible, iron, etc. They are either sorted or transported to landfills for landfill disposal. In any case, there is a high risk of environmental pollution. In particular, in the case of incineration, harmful substances often contained in wastes or harmful substances generated in the fuel process of wastes cannot be sufficiently removed by the exhaust gas treatment apparatus and may be released to the atmosphere. Therefore, there are very strict regulations on the incineration of waste such as refuse.

As a result, waste treatment companies have conducted various studies to determine whether they can be reused, rather than simply incinerating them or disposing of them in landfills, as described above. Is being developed for reuse as fuel.

In other words, when examining the composition of waste such as garbage, paper, cardboard, and fibers are 25-45% (by weight, the same applies hereinafter), rubber and plastics are 7-11%, kitchen waste and other combustible materials 7-18%, iron, aluminum, glass,
Soil, stones, and inseparable composites are 5 to 15%, and the remainder is moisture, and has a low calorific value of 2000 to 2500 Kcal / kg.

Therefore, it is known that if waste is treated and used, a fuel having sufficient energy will be obtained, and development is being attempted by related organizations in various countries to reuse the fuel.

(Problems to be Solved by the Invention) By the way, as described above, each institution has been trying to recycle waste as fuel, but a solid fuel which has not been sufficiently completed has been produced. In other words, a method is used in which waste such as garbage is simply crushed to remove incombustibles, but since decay is not completely removed, it is decomposed by microorganisms during storage and cannot be stored for a long time At the same time, a new problem has arisen, such as the emission of odors and flammable gases, causing a gas explosion. To avoid this, crush,
Although a method of further drying and compression molding after sorting is attempted, the same problem occurs due to moisture absorption during long-term storage. Further, a method has been attempted in which solid briquettes are formed by melting plastic contained in wastes, for example, but only solid fuels having poor fuel properties have been obtained. Furthermore, since refuse basically contains combustible nitrogen, volatile chlorine, sulfur, etc., it has been difficult to produce clean fuel from refuse until now.

An object of the present invention is to improve the above-mentioned problems, remove spoilage, allow long-term storage, prevent odors and gas explosions, and provide a clean fuel with good fuel properties. It is an object of the present invention to provide a method for producing a solid fuel by using waste.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention relates to
Into a mixing and storage reactor heated at a temperature of 0 ° C. or less, an additive containing pre-crushed waste and quick lime is added and mixed and heated and reacted.After degassing, compression molding, and further drying and solidification are performed. This is a method for producing solid fuel from waste to obtain solid fuel.

In the above-mentioned manufacturing method, it is desirable to mix 2-5% by weight, preferably 3% by weight of quick lime with respect to the waste.

It is desirable that the degassing be performed by heating, and that this be performed by blowing hot air.

Drying is performed in a gas containing carbon dioxide gas at 130 ° C or more and 230 ° C.
° C. or less, to produce calcium carbonate, and sieving after drying, to reflux solid fuel of a certain size or less to the mixing reaction step to obtain a high quality solid fuel,
desirable.

(Operation) By employing the method for producing a solid fuel from waste according to the present invention, the previously crushed waste is obtained by crushing waste such as refuse by a first coarse crusher and selectively removing incombustibles. And then crushed by a second crusher and, for example, selectively removing incombustible substances contained in the above-described composite material,
By adding an appropriate amount of an additive containing quick lime to the crushed waste and crushing it with a third crusher, the crushed waste and the additive are obtained as a mixture.

The mixture of the crushed waste obtained in this manner and an additive containing an appropriate amount of quick lime is charged into a mixed storage reactor heated at a temperature of 60 ° C or higher and 100 ° C or lower, whereby the water content of the waste is reduced. And quick lime (CaO) react with each other to form Ca (OH) ₂ , and the reaction proceeds while the temperature rises due to the heat of reaction. can get. The obtained first product waste is charged into a mixed degassing reactor, and further, an appropriate amount of an additive containing quick lime is added to increase the temperature by the same reaction, and a reaction containing steam and ammonia is performed. Since gas is generated, this is eliminated.
In this step, it is also possible to generate a reactive gas by blowing hot air into the mixed degassing reactor or heating the waste by another appropriate method without adding an additive. The second product waste thus obtained is put into a compression molding machine to obtain a third product waste formed into a granular form.
Next, the third product waste is put into a dry neutralization reactor to be dried, and further sieved with a sieving device to obtain a solid fuel.

In the step, the second product waste, the third product waste, or the sieved powder is refluxed to the mixed storage reactor as necessary and in a necessary amount, so that an efficient solid material is obtained. Fuel is obtained.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Referring to FIG. 1, for example, waste W such as garbage discharged from a general household or business is made of paper, cardboard,
It is composed of combustible materials such as fibers, incombustible materials such as iron, aluminum, glass, earth, and stone, and moisture contained in these materials, and is transported by trucks, packers, and other transport vehicles. Once put into the hopper 1. This hopper 1
The required amount is supplied to the first coarse crusher 3 at the required time.

The first coarse crushing machine 3 is, for example, a hydraulic low-speed driven tearing coarse crushing machine, and has a specific structure known in the art. A plurality of blades are provided on the outer periphery of each shaft.

Thus, the input waste is gripped by a two- or three-axis rotary tearing blade having different rotation speeds, and tearing is performed.
It breaks through to a strong object, is slowly torn by low-speed, high-torque hydraulic drive, and is discharged from the discharge port at the bottom of the main body. The first coarse crusher 3 is driven by a hydraulic drive system. By using a variable discharge axial piston pump, the first coarse crusher 3 is driven at high speed and low torque at normal load, and at low speed and high torque at load increase. Since the shaft rotation speed can be varied according to the operation and the load, the operation control can always be performed in an optimal state with respect to the crushing load.

The first waste W ₁ coarsely crushed by the first coarse crusher 3 is
For example, it is sent to a first sorter 5 composed of a belt conveyor or the like. This first sorter 5 is provided with a magnetic separator,
The magnetic separator removes metals such as iron. In the first sorting machine, medium-sized inorganic substances such as bottles and blocks are sorted and removed.

Metal in the first sorter 5, the inorganic substance is removed, the first waste W ₁ is sent to the second crusher 7. Second crusher 7 is made of, for example, hammer mill, waste W ₁ in the second crusher 7 is further finely crushed.

Second waste W ₂ is which is finely crushed in a second crusher 7, sent for example magnetic separator, sieving device, to the second sorter 9 made of difference in specific gravity separator. In the second sorter 9, fine metals and inorganic substances that cannot be completely removed by the first sorter 5 are removed and sent to the third shredder 11.

Second waste W additives containing appropriate quantities of quick lime with ₂ sorted by the second sorter 9 is turned to the third fine crusher 11. Third fine crusher 11, for example ring glider mill using a quick lime and a third with fine second waste W ₂ is in the third waste W ₃ further fine crushed like
Waste W ₃ are uniformly mixed in contact. Upon contact, the moisture CaO quick lime is included in the third waste W ₃ (H
₂ O) reacts with Ca (OH) _2, and this Ca (OH) ₂ is dispersed to the third in the waste W ₃ is solid. This reaction is the third
It starts in the crusher 11 and is completed in the next mixed storage reactor 13. The amount of the quick lime is 2 to 5%, preferably about 3%, based on the amount of the waste.

Appropriate amount of quick lime is added to a mixed reservoir reactor 13 and the third waste W ₃ that is uniformly crushed in third fine crusher 11. The mixing and storing reactor 13 is composed of, for example, a rotary hexagonal mixer, a ribbon mixer, or a moving screw type stirrer, and is mixed for a predetermined time while being stored. By heating the mixed storage reactor 13 with hot air or a heated tube, the reaction speed can be increased. The reaction time is 1 at a temperature of 60 ° C or higher and 100 ° C or lower in a closed state.
Although it is possible in about 5 minutes, it is preferable to carry out for 1 hour or more.

The mixture reservoir reactor 13 additives containing appropriate quantities of quick lime optionally a first product waste W ₄ which is produced by the reaction in is added to a mixed degassing reactor 15, mixed reaction At the same time, degas ammonia and the like. That is,
It is preferable to carry out at a temperature at least 5 ° C. higher than the above-mentioned temperature for 5 minutes or more in a waste state. Then put the second product waste W ₅ which is reacted in the compression molding machine 17, after densified by compression action is shaped extruded into granules. The third product waste W ₆ formed into granules by the compression molding machine 17 is charged into a dry neutralization reactor 19. In the drying and neutralization reactor 19, the temperature is increased to 130 to 230 ° C., sterilization is performed, thermochemical changes are completed, moisture is removed, and at the same time, alkali (Ca (OH) ₂ ) derived from additives is removed. Neutralize and solidify with CO ₂ gas.

That is, the following operation occurs between the mixed storage reactor 13 and the dry neutralization reactor 19.

Proteins, carbohydrates and lipids contained in organic matter are denatured and partially hydrolyzed by the action of heat and alkali contained in additives. By the action of alkali and mechanical action, paper,
Bacteria are killed as wood and plant residues are unraveled into fibers.

In addition, acidic substances (H ₂ S, organic acids, etc.) generated by organic decay or decomposition are neutralized, ammonia evaporates, moisture evaporates, and waste is dried.

Quick Ca (OH) ₂ produced from the ram is neutralized with CO ₂ in the drying gas, with CaCO ₃ occurs insoluble, waste is coated thereto.

Ultimately, the additives solidify by dehydration and CaCO ₃ generation, linking other substances, and the crushed wastes have low moisture and CaCO 3
Biologically stabilized by the coating of ₃ .

The granular waste thus obtained is sieved by the sieving device 21 and is taken out as solid fuel.

Among the solids sieved by the sieving device 21, solids smaller than a certain size are required to satisfy a certain size.
The mixed storage reactor 13 is refluxed and charged again.

First generating waste W ₄ which are mixed while being stored in the mixing reservoir reactor 13, before being added to a mixed degassing reactor 15, is checked stable quality, for example, variations in pH value, etc. If a certain quality is not achieved, a mixed storage reactor
Refluxed to 13. This reflux ratio varies depending on the reaction time and reaction conditions in the mixed storage reactor 13, but the maximum
50% reflux is sufficient. In short, first generation waste W ₄
When the quality of the mixture satisfies a certain level, the mixture is charged into the mixed deaeration reactor 15.

Also, the second product waste reacted in the mixed degassing reactor 15
W _5, before being introduced into the compression molding apparatus 17, pH value and whether the check is performed ammonia concentration measured constant reaction achievement ratio in the exhaust gas is maintained, certain reaction achievement rate If not achieved, it is refluxed to the mixed storage reactor 13. Therefore, only the second product waste W ₅ maintaining a constant reaction achievement rate is being introduced in the compression molding machine 17.

As described above, the first product waste W ₄ reacted in the mixed storage reactor 13, the second product waste W ₅ reacted in the mixed degassing reactor 15, or dried and neutralized in the dry neutralization reactor 19. The solids that have been sieved and sieved by the sieving device 21 are repeatedly refluxed until they reach a certain material composition, a certain reaction achievement rate, and a certain size. The resulting solid fuel can be removed as a homogeneous and clean fuel.

In the process from the third crusher 11 to the mixed degassing reactor 15,
Additives containing quick lime are added in the required amount in each step and chemically reacted to remove spoilage and bad odor. It can be stored as fuel for a long time, and can be used as a safe fuel without generating methane gas and causing gas explosion.

The present invention is not limited to the above-described embodiment, but can be embodied in other modes by making appropriate changes.

[Effects of the Invention] As can be understood from the description of the embodiments as described above, according to the present invention, since the configuration is as described in the claims, clean fuel from waste such as garbage can be obtained. Solid fuel can be obtained. In addition, the obtained solid fuel is subjected to a heat reaction treatment of an additive containing quick lime and waste, and the reaction achievement rate is reliable and high,
It is physically, chemically and biologically stabilized and can be stored for long periods. Further, it is possible to provide a safe fuel that does not cause a gas explosion or a dust explosion.

In addition, if sufficient characteristics are not obtained in each step, the fuel can be refluxed if necessary, and a fuel of stable quality can be secured.

[Brief description of the drawings]

FIG. 1 is an embodiment of the present invention, showing a conceptual process for obtaining solid fuel from collected waste. DESCRIPTION OF SYMBOLS 1 ... Hopper, 3 ... 1st coarse crusher, 5 ... 1st sorter, 7 ... 2nd crusher 9 ... 2nd sorter, 11 ... 3rd fine crusher, 13 ... Mixing Storage reactor 15: Mixed degassing reactor, 17: Compression molding machine, 19: Dry neutralization reactor 21: Sieving device, CaO: Additive including quick ram

Continuation of the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) C10L 5/46-5/48 B09B 3/00 WPI / L (QUESTEL)

Claims (6)

(57) [Claims] 1. A mixed storage reactor heated at a temperature of 60 ° C. or more and 100 ° C. or less is charged with an additive containing preliminarily crushed waste and quick lime, and mixed and heated to react.
A method for producing solid fuel from waste, comprising compression molding and drying to obtain a solid fuel. 2. The method for producing solid fuel from waste according to claim 1, wherein 2-5% by weight of the quick lime is mixed with the waste. 3. The method according to claim 1, wherein the degassing is performed by heating. 4. The method for producing a solid fuel from waste according to claim 1, wherein hot air is blown out of the air. 5. The disposal according to claim 1, wherein the drying is performed in a gas containing carbon dioxide at a temperature of 130 ° C. or more and 230 ° C. or less to generate calcium carbonate. A method for producing a solid fuel by using a material. 6. The method according to claim 1, wherein the solid fuel having a certain size or less is refluxed in the mixing and heating reaction step.
(5) The method for producing a solid fuel from waste according to any of (5).