JPH0633384B2 - Solid fuel - Google Patents

Description

TECHNICAL FIELD The present invention relates to a solid fuel which is a compression molded body composed of a plastics or pitch-like material and a fuel burning ash, and in particular, a waste plastics , Waste pitch, oil coke combustion ash, heavy oil combustion ash, etc. can be reused as fuel resources.

[Prior Art] Recently, an enormous amount of plastic products have been used, but with this, an enormous amount of waste plastics is generated. Many of these waste plastics are flammable, but if they are left as they are, the combustion temperature is too fast, the calorific value is too large, and the fuel temperature becomes too high. It causes deterioration in a short period of time, or during combustion, the plastics themselves melt and stick to the walls of the combustion boiler, or the molten plastics flow and hinder combustion. It was difficult to use.

Pitch-like substances such as coal residue and coal pitch generated in the distillation process of organic compounds can be used as fuels, but they melt and flow during combustion and are difficult to use as fuels for the same reason as above.

The amount of heavy oil combustion ash discharged from a thermal power plant and the oil coke combustion ash discharged from an oil coke combustion boiler are enormous. It is mixed with the fuel of the cement kiln and burned, or mixed with oil and fueled, but because it is difficult to burn, in reality a huge amount is left unloaded.

[Problems to be Solved by the Invention] The present inventors simultaneously solve the above-mentioned various problems when using waste plastics, waste pitch-like materials, oil coke combustion ash, heavy oil combustion ash, etc. as fuel. As a result of diligent research on means for solving the problem, a solid fuel composed of pelletized compacts obtained by compounding combustion ash obtained by ordinary combustion of oil coke or heavy oil with plastics or pitch products, and compression-molding the compound. However, solving the above problems,
The present invention has been completed by finding that it can be suitably used as a fuel.

[Means for Solving the Problems] That is, the present invention is a compression molded article comprising a plastics or pitch-like material and a combustion ash containing 5 to 25% by weight of an inorganic component and 95 to 60% by weight of a carbon component. The present invention relates to a solid fuel characterized in that

The present invention will be described in more detail below.

The plastics used in the present invention are not particularly limited as long as they are flammable, but those having a particularly high burning rate and not producing a large amount of toxic substances after burning are preferable, for example, (a) Acrylic nitrile-butadiene-styrene copolymer (ABS resin), acrylonitrile-styrene copolymer (AS resin), acrylic resin such as poly (meth) acrylic acid (ester), (b) polypropylene, polyethylene, polyisobutylene An olefin polymer such as ethylene-vinyl acetate copolymer, an ethylene addition polymer such as polystyrene, (c) a synthetic rubber or a natural rubber such as polybutadiene, polyisoprene, a butadiene-styrene copolymer, and (d) Condensation of polyacetal, polyester, polyamide (nylon-6, nylon-6,6), etc. It can be exemplified one or two or more thermoplastic resin selected from the group consisting of polymer.

The plastics used for molding the solid fuel of the present invention are waste plastics that are discarded after various plastics moldings are used temporarily or for a long time,
Alternatively, it may be an off-molded product, a burr part, a cutting residual part or an ear part, which is generated during molding of various plastics, and is particularly suitable for uniform mixing with combustion ash and compression molding of the compound. In addition, it is preferable that the powder is cut or crushed into an appropriate size or shape by means such as crushing, crushing, cutting, or tearing, and further, as the plastics used for molding the solid fuel described above. , Maximum length is less than 5000μm, especially 2000μm
Hereafter, it is most preferable that the powder is "fine particles (spherical), rod-shaped, or strip-shaped powder" having a particle size of 1 to 1500 μm.

The pitch-like material used in the present invention is a solid at a temperature of 40 ° C. or lower and can be pulverized into a powder. Further, it is heated to be in a molten state. For example, coal pitch. In addition, it is a bottom residue that is produced in the distillation process of various organic compounds, for example, a vanillin bottom residue.

For the above-mentioned solid fuel, the finer the powder of the plastics or the pitch-like substance, the easier the uniform blending with the combustion ash becomes, and the better the fluidity or moldability of the homogeneous blend in compression molding becomes. Moreover, the strength of the obtained compression molded article such as crushing strength is increased, which is suitable.

By shortening the ignition time and first gasifying and burning the plastic, the fuel becomes porous and oxygen easily enters the inside, which contributes to the effect of facilitating the fuel.

The combustion ash used for solid fuel contains (i) an inorganic component in a proportion of 5 to 25% by weight, and (ii) a carbon component (combustible organic component, hydrocarbon component or unburned carbon). ) Is a "combustion ash" containing 95 to 60% by weight.

That is, in the present invention, the combustion ash suppresses the combustion rate of the plastics or pitch-like material contained in the solid fuel to a low level, and the plastics or pitch-like material itself melts and flows during combustion. It has an action of preventing solidification and maintaining the shape of solid fuel, and has the above-mentioned composition, for example, "unburned carbon obtained by burning oil coke or heavy oil in a boiler or the like. "Combustion ash containing about 60 to 95% by weight of components".

In particular, the inorganic component contained in the combustion ash is contained in the combustion ash, uniformly mixed with the plastics or pitch-like material, and compression molded to produce a solid fuel. Since the solid fuel of the invention is uniformly dispersed and present, (a) action of appropriately suppressing the burning rate of the solid fuel (b) action of suppressing the heat generation amount of the solid fuel during combustion (c) strength of the solid fuel To improve, and (d) to maintain the shape of the solid fuel during combustion,
It contributes to the addition to the solid fuel of the present invention, which is the main feature of the present invention.

Further, as the inorganic component, for example, a silicon component such as SiO ₂ , an aluminum component such as AI ₂ O ₃ , a calcium component such as CaO and CaCO ₃ , an iron component such as Fe ₂ O ₃ and other metal compounds (MgO, Inorganic substances such as TiO ₂ , V ₂ O ₅ , Na ₂ O and K ₂ O) can be mainly mentioned.

In the present invention, the combustion ash used for molding the solid fuel is
The calorific value is preferably 5000 to 8000 kcal / kg, particularly 5000 to 7000 kcal / Kg in order to suppress the calorific value of the plastics or pitch-like material in the solid fuel.

The combustion ash used for molding the solid fuel of the present invention has an average particle size of 0.1 to 1000 μm, particularly 0.5 to
Fine particles having a size of about 500 μm are preferable for uniform blending with plastics or pitch-like materials.

The solid fuel of the present invention has a usage ratio of plastics or pitch-like material and combustion ash (plastics or pitch-like material / combustion ash) of 0.1 to 2.0 g / g, particularly 0.2 to 0.5 g / g.
It is preferably about g in terms of strength, calorific value, fuel speed, etc. of the solid fuel which is a compression molded body. Further, in the present invention, the content of the inorganic component in the solid fuel is about 5
Optimally, it is -20% by weight.

In the present invention, the solid fuel is, in addition to plastics or pitch-like substances and combustion ash, (a) water, (b) vegetable organic components (vegetable fiber components) such as fruit shavings, (c) deteriorated At least one or more oily components such as waste lubricating oil and waste oil,
It may be incorporated in an amount of about 55% by weight or less, particularly 50% by weight or less.

In the above case, the content of (A) water in the solid fuel is 20% by weight or less, particularly 15% by weight.
The content is about 50% by weight or less, particularly 45% by weight or less, and (C) the content of oily component is 30% by weight or less, particularly 25% by weight or less. It is appropriate for each to be a degree.

The solid fuel of the present invention has a calorific value of 5000 to 800.
0 kcal / kg, especially about 5500-7500 kcal / kg, and a solid fuel at 900 ° C (combustion test in which a cylindrical pellet having a diameter of 5 mm and a length of 5 mm is used as a sample and is burned in an electric furnace) It is preferable that the fuel time is 200 to 500 seconds.

The method for producing a solid fuel according to the present invention is, for example, a method of mixing and blending powder particles of plastics and combustion ash with the above-mentioned water, waste oil, etc., if necessary, and then a twin-screw extruder. Using a uniaxial extruder, a briquette machine, etc., the mixture is continuously compression extruded to form a thin rod-shaped compression molded body, and at the same time, the thin rod-shaped compression molded body is formed into an appropriate length. Continuously cut into
A method for producing a solid fuel in the form of a pellet having a columnar shape (for example, a circle or a prism), a spherical shape, or an elliptical shape can be mentioned.

The above-mentioned compression molding may be carried out at a temperature within the range from room temperature to around the softening temperature of the plastic, for example, about 5-25
0 ° C, especially about 10 to 200 ° C, more preferably 15
It may be carried out at a temperature within the range of about 150 ° C. The temperature at the time of extrusion molding of the compression molded body in the compression molding gradually rises due to the heat generated at the time of compression molding, even if it is initially started at room temperature (10 to 30 ° C.), and is about 50 ° C. or higher, particularly 60 to 1 ° C.
The temperature reaches about 00 ° C.

The compression molded article of this invention has a diameter of 2 to 50 mm, especially 3 to 4 mm.
0 mm and length is 2-50 mm, especially 3-4
Cylindrical or prismatic pellet-shaped compact having a size of about 0 mm
Alternatively, a granular, spherical, or elliptical shaped body having a maximum diameter of 2 to 50 mm, particularly about 3 to 40 mm is preferable. The compression molded body has a crushing strength (a sample of a cylindrical pellet having a diameter of 5 mm and a length of 5 mm) of 1.5 kg or more, particularly 2.0 to 50.
It is preferably kg.

In the above-mentioned compression molding, when a large amount of water is added to the mixture of plastics and combustion ash and used, this water mainly acts as an auxiliary agent for the wet molding so that the extruded compression molded body contains About 15% by weight or less, especially 10% by weight
The following water content ratios are preferable.

In addition, in the above-mentioned compression molding, by adding a vegetable organic component (vegetable fiber component) to the mixture of plastics and combustion ash and using it, a lubricant-like action effect is shown at the time of compression molding, As a result, it is possible to save mechanical energy in compression molding, and the solid fuel consisting of a compression molded product containing a vegetable fiber component has a tendency that the vegetable fiber component melts and flows of the plastics during its combustion. Can be further prevented and is also consumed as a part of fuel.

As such a vegetable organic component, various fruits, squeezed dregs of food materials, etc. can be used. The diaphragm residue can be mentioned.

Examples of the oily component include waste lubricating oils, cutting oils, and other waste oils from machine plants, and waste solvents such as toluene, styrene, and phenol from chemical plants.

Furthermore, the above-mentioned oil coke is a solid residue (raw petroleum coke) or raw petroleum coke that remains when a light distillate is recovered by thermally decomposing a heavy residual oil obtained in a petroleum refining process. It is a petroleum coke such as a calcined petroleum coke in which the solid carbon content is increased by burning to further remove volatile components.

[Examples] Hereinafter, examples will be described more specifically.

As a compounding example of each raw material used in the embodiment of the solid fuel of the present invention, the following examples of ratios of compounding amounts (parts by weight) are given below.
It can be shown in the table.

In these compounding examples, the waste plastics are
Incompletely polymerized ABS resin powder with an average particle size of about 1000 μm (heating value: 10000 kcal / kg), PE resin powder with an average particle size of about 1000 μm (heating value: 100
00 kcal / kg) or PP resin powder having an average particle size of about 1000 μm (heat generation amount: 10000 kcal / kg),
The pitch-like material is vanillin residual powder (heating value: 6100 kcal / kg) having an average particle diameter of about 1000 μm.

Oil coke combustion ash contains about 10% by weight of inorganic substances [Si
O ₂ : 1.7% by weight, V ₂ O ₅ : 5.3% by weight, others (Fe ₂ O
₃ , Al ₂ O ₃ , MgO, TiO, K ₂ O, SO _3, etc.): 0.01 to 2.
2 wt%] and the balance is carbon component (unburned carbon)
Which is a combustion ash having a calorific value of 7,500 kcal / kg. Heavy oil combustion ash contains about 15% of inorganic substances [Fe ₂ O ₃ :
3.1% by weight, V ₂ O ₅ : 4.3% by weight, others (SiO ₂ , Al
₂ O ₃ , CaO, MgO, P ₂ O ₅ , Na ₂ O, NiO, etc.): 0.02 ~ each
0.8% by weight], the balance is a carbon component (unburned carbon), and the calorific value is 5500 kcal / kg.

The squeezed residue of mandarin orange contains about 76% by weight of water, and the calorific value in a dry state is 4502 kcal / kg. Also,
The calorific value of waste oil is 8600 kcal / kg.

Example 1 The raw materials of formulation example I were supplied to a mixer, and the mixture obtained by mixing and blending was mixed with a biaxial compression (extrusion) molding machine (110 kg).
/ H, power 7.5 kW) at a temperature of 70 ° C. while extruding while compressing, the extruded molded body is continuously cut and cooled, and a cylindrical pellet (diameter 5 mm, length 5 mm ( A compression molded body and a solid fuel having a water content of about 5% by weight) were compression molded.

According to a combustion test in which the cylindrical pellets are burned in an electric furnace, ignition at 900 ° C. is quick within 1 second, the cylindrical pellets do not easily collapse during combustion, and There was no sticking to the electric furnace wall due to melting of plastics, no flow deformation, etc., and its combustion state and combustion efficiency (unburned carbon component; 2.5 wt%) were good. The results of the combustion test are shown in Table 2.

Further, this cylindrical pellet could be satisfactorily combusted in the fluidized bed boiler.

Other properties of this columnar pellet are shown in Table 2.

Comparative Example 1 For comparison, in a combustion test using an ABS resin in an electric furnace, the ABS resin immediately becomes a molten state,
It burned down in about 35 seconds.

Comparative Example 2 For comparison, in a combustion test using an electric coke using an oil coke, the oil coke burned at a surface burning time of about 550 seconds.

Examples 2 to 7 Using the raw materials of formulation examples II to VII, solid fuels of pellets (compression molded bodies) having the same shape as in Example 1 were formed.

The properties of these cylindrical pellets are shown in Table 2.

Each of the pellets (solid fuel) obtained in Examples 4 to 7 had an ignition time of about 1 second or less in a combustion test at 900 ° C., and the pellets obtained in Example 1 It can be burned in a combustion state substantially similar to (solid fuel).

In addition, regarding the pellets (solid fuel) obtained in Examples 1 to 7 and the ABS resin pellets obtained in Comparative Example 1, the contents of the burning time in the burning test at 900 ° C. are shown in FIG. 1 and FIG. The details are shown in Table 2.

[Advantages of the Invention] The present invention can be applied to fluidized bed boilers, etc. for waste plastics, waste pitch-like waste oil, etc., which generally have a high burning rate and a large calorific value, and which is problematic to use as they are as fuel. It relates to an excellent solid fuel that can be reused as a usable solid fuel,
It is extremely effective as an energy-saving technology.

That is, the solid fuel of the present invention has (i) sufficient strength to be burned in a fluidized bed boiler or the like, and (ii) so that the burning speed of plastics or pitch-like material is appropriately slowed. It is controlled, and (iii) the calorific value is suppressed, so there is almost no danger that the combustion furnace will get too hot and damage the combustion furnace.
(Iv) The combustion ash does not melt the plastics or pitches contained in the solid fuel to adhere to the combustion furnace wall or melt and flow, and maintains a very suitable combustion state. It is possible.

[Brief description of drawings]

FIG. 1 is a bar graph showing in detail the “content of combustion time” in the combustion test of the solid fuel of the present invention (Examples 1, 4 to 7) and the ABS resin pellet (Comparative Example 1).

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Yasumasa Ide 1980 Okiyama, Ogushi, Ube City, Yamaguchi Prefecture, Ube Industries, Ltd., Machinery & Plant Business Headquarters (56) Reference JP-A-61-28589 (JP, A) ) JP-A-52-144001 (JP, A) JP-A-59-227978 (JP, A)

Claims (4)

[Claims] 1. A solid fuel comprising a plastic or pitch material and a fuel combustion ash containing 5 to 25% by weight of an inorganic component and 95 to 65% by weight of a carbon component. 2. The fuel combustion ash has a calorific value of 5000 to 8000 kcal / which is obtained by combustion of oil coke or heavy oil.
The solid fuel according to claim 1, which is kg of combustion ash. 3. The use amount ratio of plastics or pitch-like material and fuel combustion ash is 0.2 to 2.0 g of plastics or pitch-like material per 1 g of fuel combustion ash. Solid fuel. 4. A combustion time when a combustion test is performed in an electric furnace at 900 ° C. using a cylindrical pellet having a calorific value of 5000 to 9000 kcal / kg and a diameter of 5 mm and a length of 5 mm as a sample. The solid fuel according to claim 1, wherein the solid fuel is 200 to 500 seconds.