JP3067827B2 - Hybrid fuel manufacturing method - Google Patents

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 a hybrid fuel obtained by mixing a solid fuel made of municipal solid waste and a natural fuel.

[0002]

2. Description of the Related Art Conventionally, petroleum, coal, charcoal, wood chips and the like have been known as natural fuels. For example, coal among these natural fuels is known to produce a calorific value of 5,000 to 8,000 kcal per kilogram. ing.

[0003] Recently, a municipal solid waste crusher,
When a solid fuel is manufactured by drying and solidifying with a dry solidifier through a crushing machine, a sorting machine, a mixed heating reactor, and a compression molding machine, each or all of the processes of the crushing machine, the crushing machine, and the mixed heating reactor In addition, it has been proposed to obtain a solid fuel as a waste by adding an appropriate amount of an alkaline earth metal oxide such as CaO. It is considered that only a calorific value of, for example, about 3500 to 4500 kcal per kilogram can be obtained from the solid fuel of the municipal solid waste.

[0004]

However, if only the above-mentioned conventional natural fuel alone is used, there is a problem that the cost is high. In addition, there is a problem that when only the solid fuel made of the municipal solid waste is used, the calorific value can be obtained only about half of the calorific value of the natural fuel.

[0005] It is an object of the present invention to reduce the cost of fuel by reducing the amount of natural fuel used in order to improve the above-mentioned problems, to promote the effective use of solid fuel by municipal solid waste, and to further improve the resources. It is an object of the present invention to provide a method for producing a high calorific value hybrid fuel composed of a municipal waste natural fuel and an alkaline earth metal compound for the purpose of environmental protection and environmental protection.

[0006]

In order to achieve the above-mentioned object, the present invention provides a method for supplying municipal waste to a waste receiving tank (1), crushing the municipal waste with a crusher (3), and further crushing the municipal waste. After the crushing treatment by the machine (7), the mixed heating reactor (11)
The mixture is heated and reacted at a temperature of 60 ° C. or more and 100 ° C. or less in a closed state, and then subjected to compression molding and drying and solidification, and the waste receiving tank (1), crusher (3), crusher (7) After mixing the solid fuel from municipal solid waste obtained by adding an alkaline earth oxide to each step or all steps of the mixed heating reactor (11), and natural fuel, This is a method for producing a hybrid fuel, characterized by performing compression molding or granulation.

[0007]

According to the hybrid fuel production method of the present invention, a solid fuel obtained from municipal solid waste and a natural fuel are mixed. In the manufacturing process of the solid fuel, the waste receiving tank (1), the crusher (3),
An alkaline earth oxide is added to each step or all steps of the crusher (7) and the mixed heating reactor (11). The addition of the alkaline earth oxide not only maintains good sanitation in the process of producing solid fuel from municipal solid waste, but also removes nitrogen contained in municipal solid waste as ammonia, and further reduces Since harmful substances such as sulfur oxides derived from natural fuels generated during fuel combustion react with alkaline earth compounds and become harmless,
The product is a clean fuel for environmental protection.

By subjecting a mixture of a solid fuel and a natural fuel to compression molding or granulation, a compression molded or granulated hybrid fuel can be obtained. Since the solid fuel from the municipal solid waste is fibrous, the hybrid fuel is easily formed at the time of forming the hybrid fuel, and the forming strength is increased. Furthermore, since it can be produced at low cost while having a sufficiently high calorific value because it contains natural fuel, it can be used for many purposes and is effective for resource conservation.

[0009]

An embodiment of the present invention will be described in detail with reference to the drawings.

First, a method for producing solid fuel from municipal solid waste used in the present embodiment will be described.

Referring to FIG. 2, for example, municipal solid waste G removed from ordinary households or offices is composed of combustible materials such as paper, cardboard, and fibers, iron, aluminum, glass, and the like.
It is composed of incombustible substances such as soil and stone, and water contained therein, and is transported by, for example, a truck such as a truck or a packer truck, and is then temporarily put into a waste receiving tank 1 composed of a pit or the like. Is done. The required amount of waste G is charged into the crusher 3 from the waste receiving tank 1 at a required time.

The crusher 3 is, for example, a hydraulically driven low-speed tearing crusher, and its concrete structure is known, so that detailed description is omitted, but the crusher 3 has two or three shafts having different rotation speeds. A plurality of blades are provided on the outer periphery of each shaft.

The input waste G is gripped by a two- or three-axis rotary tearing blade having different rotation speeds, tears, breaks through to a strong one, and is slowly driven by a low-speed, high-torque hydraulic drive. It is torn and discharged from the outlet at the bottom of the body. The disintegrator 3 is driven by a hydraulic drive system. By using a variable discharge axial piston pump, it is necessary to perform high-speed and low-speed torque during normal load, and low-speed and high-speed torque operation when load increases. The rotation speed of the shaft can be changed according to the condition, so that the crushing load can always be controlled in an optimal state.

The first waste G1 crushed by the crusher 3
Is sent to a first sorter 5 composed of, for example, a belt conveyor. The first separator 5 is provided with a magnetic separator, which removes metals such as iron and non-ferrous metals and removes harmful hazardous substances. In the first sorting machine 5, medium-sized inorganic substances such as bottles and blocks are sorted and removed.

When metals and inorganic substances are removed by the first sorter 5, the second waste G2 is sent to the crusher 7. The crusher 7 is made of, for example, a hammer mill, and the second waste G2 is further finely crushed by the crusher 7.

The third waste G3 finely pulverized by the crusher 7 is sent to a second separator 9 composed of, for example, a magnetic separator, a sieve, a specific gravity difference separator, and the like. In the second sorter 9, fine metals and inorganic substances that could not be completely removed by the first sorter 5 are removed, and the fourth waste G4 is mixed with the mixed heating reactor 1.
Entered into 1. In the mixed heating reactor 11 or in a previous step, a reactant such as an alkaline earth oxide such as CaO is added to the waste at a ratio of, for example, 5 to 10%.

The mixing and heating reactor 11 is, for example, a rotary 6
It consists of a square mixer, a ribbon mixer, or a moving screw type stirrer, and is heated and mixed for a certain period of time while being stored. As a heating means in the mixed heating reactor 11, by using hot air or a heating tube,
The reaction speed can be increased. It is preferable to carry out in a closed state, for example, at 60 ° C. or more and 100 ° C. or less for 1 hour or more.

Next, the fifth waste G5 reacted in the mixing and heating reactor 11 is charged into a compression molding machine 13 to increase the density by a compression action, and then extruded to be granulated.
Sixth waste G6 formed into granules by the compression molding machine 13
Is supplied to the drying and solidifying device 15. In the drying and solidifying device 15, the temperature is raised to, for example, 130 to 230 ° C., sterilization is performed, thermochemical changes are completed, and at the same time as removing water, the contained alkaline Ca (OH) _{2 and the} like are mixed with CO ₂ gas. By solidifying and solidifying, solid fuel S made of municipal waste is obtained.

It should be noted that feedback may be fed from the drying and solidifying unit 15 to the mixing and heating reactor 11 as needed.

In the solid fuel S obtained from the municipal solid waste thus obtained, the nitrogen content of the municipal solid waste is removed as ammonia, the NOx generation load by the nitrogen contained in the fuel itself is reduced, and the solid fuel S is used as clean energy. Quality can be improved.

In the present embodiment, it has been confirmed that production as a fuel particularly suitable for a fluidized-bed boiler has a low mechanical load and is effective in view of combustion characteristics.
It is mechanically easy and effective to produce granules of approximately 5 mm to 10 mm.

When the above-mentioned municipal solid waste G is put into the waste receiving tank 1 and the solid fuel S is produced from the municipal solid waste through the processing steps up to the drying and solidifying unit 15, the waste receiving tank is used. 1 or the crusher 3 is subjected to a physicochemical reaction treatment by adding, for example, CaO as an alkaline earth metal oxide to waste G such as municipal waste for the purpose of deodorizing and suppressing spoilage fermentation. . In this case, C
The addition amount of aO is preferably about 0 to 30% of the total addition amount.
Even if it exceeds 30%, no significant effect is exhibited.

That is, by actually introducing CaO into the waste receiving tank 1 and the crusher 3, the municipal solid waste receiving and storing facility which this kind of facility had to overcome in common was hitherto. The generation of offensive odor can be prevented. And the effect of CaO has the effect of suppressing spoilage / fermentation and the occurrence of insects.

Also, in the crusher 3 for crushing municipal waste, by introducing CaO in advance, it is possible to prevent odor and prevent the plant from corroding due to the adhesion of anaerobic fermentation products. . It is desirable that the input amount to the waste receiving tank 1 be in the range of 10% to 20% of the total input amount.

Further, the second sorter selected by the first sorter 5 is used.
When the waste G2 is put into the crusher 7, CaO is also put into the crusher 7 to perform mixing and the first chemical reaction by CaO. In this case, the addition amount of CaO is desirably 0 to 50% of the total addition amount to perform the physicochemical reaction treatment.

The purpose of charging the crusher 7 is to mix the CaO and the dust uniformly in the crusher 7 and at the same time mechanically contact the solids with each other to promote the reaction by the CaO. The municipal dust generated from this kind of conventional crushing process is biologically active, and the influence of pathogenic bacteria on the environment has been recognized to a considerable extent. In this regard, the introduction of CaO into the crusher 7 not only promotes the reaction but also has a remarkable effect on improving the working environment in the factory.

Further, the fourth waste G4 selected by the second sorter 9 may be charged into the mixing and heating reactor 11 and CaO may be charged at the same time. In this case, the addition amount of CaO is desirably 20% to 100% of the total addition amount. The purpose of introducing CaO in this step is to complete the reaction with CaO.

In some cases, all of the waste receiving tank 1, the crusher 3, the crusher 7 and the mixing heating reactor 11
It is also possible to add aO in an appropriate amount.

Therefore, this is a step for adding CaO, reacting with municipal waste, converting it into a physicochemically stable substance, and excluding NOx components such as ammonia from the waste. The compression-molded granular intermediate product has a temperature of 50 ° C. or higher due to heating and an exothermic reaction of CaO.

In a subsequent drying step, water is removed.
The solid fuel S is solidified by the reaction between the calcium and the carbon dioxide in the combustion gas, and is made of municipal solid waste as an easily handled intermediate product. In addition to obtaining an intermediate product that is easy to handle, the compression molding machine 13 can improve the strength of the compact and prevent it from scattering due to the "trapping" of fine powder, the "prevention of scattering" of garbage and the like and fine debris, and the mixing effect of dust components. Can be achieved. Further, the drying and solidifying device 15 improves the environmental hygiene and safety of the treatment plant by removing the moisture of the molded body, improving the strength of the molded body from which the moisture has been removed, and stabilizing the alkaline earth oxide in the molded body. Thus, the strength of the molded body can be improved and the chemical stability can be achieved.

Next, a production method in which a hybrid fuel is obtained by mixing the solid fuel S made of municipal solid waste obtained by the production method described above and a natural fuel N mainly using coal will be described with reference to FIG. explain. In FIG. 1, a solid fuel S made of municipal solid waste is introduced into a fine powder crusher 17 and further crushed into fine particles. The fine granular solid fuel crushed by the pulverizer 17 is supplied to a specific gravity difference separator 19, which further removes impurities (incombustibles) such as glass and iron chips.

The granular solid fuel from which impurities have been removed by the specific gravity difference separator 19 is charged into a mixer 21 and
The natural fuel N, which is mainly coal, is charged into the mixer 21. Therefore, in the mixer 21, the particulate solid fuel and the natural fuel N are mixed at a fixed rate for a fixed time.

The mixture subjected to the mixing process in the mixer 21 is put into, for example, a compression molding machine 23 and compression-molded.
Further, by performing the drying treatment under a certain condition in the dryer 25, a hybrid fuel _HA of a small solid material having a size of, for example, soybean charcoal or briquette can be obtained.

The mixture subjected to the mixing process in the mixer 21 is charged into a granulator 27 in some cases. Water or Ca (OH) ₂ is added to the granulator 27 and granulated under certain conditions. Further, by being dried under a certain condition in the dryer 29, a layer of natural fuel N adheres to the outer peripheral portion with the solid fuel S made of municipal waste as a core, and a granular material having a size of, for example, about soybeans. the fact that the granules hybrid fuel H _B is obtained.

[0035] In this way the small solid hybrid fuels H _A and Zotsububutsu hybrid fuel H _B obtained, since natural fuel N is contained at a constant rate, the conventional 10
It can be manufactured at a lower cost than the cost of 0% natural fuel N, and the sulfur and chlorine contained in the natural fuel N are absorbed by the CaO contained in the solid fuel S from municipal waste. Is done.

In addition, solid fuel S from municipal solid waste
Is contained at a certain ratio, and the solid fuel S contains CaO, so that the exhaust gas is cleaned and becomes a clean fuel without the exhaust gas.

By using this hybrid fuel,
For example, it can be used as a fuel for a small boiler such as a simple stove, etc., and becomes anthracite as a grade.Furthermore, since it contains solid fuel S from municipal waste, it becomes fibrous and has an effect as a binder. , Making it easier to granulate. As the calories, it has the same calories as low-grade coal, which is the intermediate between natural fuel N and solid fuel S from municipal solid waste, and can be sufficiently used as fuel, and can be used for various purposes of various fuels. .

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

[0039]

As can be understood from the above description of the embodiments, according to the present invention, since the hybrid fuel has the configuration as described in the claims,
Since natural fuel is contained at a certain ratio in solid fuel made of municipal waste, it can be manufactured at a lower cost than the conventional cost of 100% natural fuel.

By using this hybrid fuel,
For example, it can be used as a fuel for small boilers such as simple stoves, and the quality is anthracite,
Furthermore, since it contains solid fuel from municipal waste, it becomes fibrous, has an effect as a binder, and is easily granulated. For this reason, a solid fuel of any shape having high breaking strength can be obtained. As calorific value, it has calories equivalent to that of low-grade coal, which is intermediate between natural fuel and municipal solid waste solid fuel. That is, the hybrid fuel obtained by the present invention satisfies both resource conservation and environmental conservation by synergistic effects of solid fuel from municipal solid waste and natural fuel. In addition, the alkaline earth oxides added in the municipal solid fuel production process fix harmful substances such as sulfur oxides generated during combustion of the product hybrid fuel and render them harmless.
The calorific value is increased as compared with the solidified waste fuel, and a fuel of a constant quality can be obtained, so that the fuel can be used for various purposes.

[Brief description of the drawings]

FIG. 1 is a process explanatory view of one embodiment of a method for producing a hybrid fuel according to the present invention.

FIG. 2 is an example of a process for producing solid fuel from waste used in the present invention.

[Explanation of symbols]

S Solid fuel from municipal solid waste N Natural fuel H _A Small solid hybrid fuel H _B Granulated hybrid fuel 17 Fine crusher 19 Specific gravity difference separator 21 Mixer 23 Compression molding machine 25 Dryer 27 Granulator 29 Dryer

Claims (1)

(57) [Claims] 1. A waste receiving tank for municipal waste (1)
After crushed by a crusher (3) and further crushed by a crusher (7), mixed and heated at a temperature of 60 ° C. or more and 100 ° C. or less in a closed state with a mixing and heating reactor (11). A reaction treatment is performed, and then a compression molding treatment and a dry solidification treatment are performed, and each step or all of the waste receiving tank (1), the crusher (3), the crusher (7), and the mixing heating reactor (11) are performed. A hybrid fuel characterized by mixing solid fuel from municipal solid waste obtained by adding alkaline earth oxides to natural fuel and natural fuel, followed by compression molding or granulation. Production method.