JPH08100206A - Pulverized coal transportability improving agent - Google Patents

Abstract

PURPOSE: To greatly improve the transportability of pulverized coal having an average HGI of raw coal of a specific value or above by sticking an org. compd. which has polar groups and is substantially soluble in water to the pulverized coal. CONSTITUTION: This pulverized coal transportability improving agent consists of the org. compd. which has the polar groups, such as anionic surfactants, cationic surfactants, amphoteric surfactants, lower fatty acids and lower fatty acid salts, and is substantially soluble in water. Such pulverized coal transportability improving agent is stuck to the dried pulverized coal having the average HGI (average grindability index) of the raw coal of >=30. As a result, the transportability of the pulverized coal is greatly improved and, therefore, the restriction on coal kinds is removed, piping closing and scaffolding in a hopper are prevented and the stable blowing of the pulverized coal in large amt. are made possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention improves the transportability of pulverized coal blown from the inlet of a metallurgical furnace or a combustion furnace, and makes it possible to stably blow a large amount of pulverized coal. The present invention relates to a method of operating a metallurgical furnace or a combustion furnace using the.

[0002]

In the operation of metallurgical furnaces such as blast furnaces,
The method of alternately charging coke and iron ore from the top of the furnace has been generally used, but in recent years, a part of the coke charged from the top of the furnace was replaced with pulverized coal that is inexpensive, highly combustible, and has a high calorific value. The method of substituting by blowing from the blowing port of the blast furnace together with hot air is actively used. Such a pulverized coal blowing operation method is superior in that the fuel cost can be reduced as compared with the all coke operation.

Further, coal has been reviewed as an alternative to heavy oil as a fuel for combustion furnaces such as boilers. CWM (coal-water slurry), COM (coal heavy oil mixed fuel), pulverized coal, and the like are used as coal in the combustion furnace. Among them, the pulverized coal combustion furnace particularly requires other media such as water and oil. And because it doesn't, it is getting attention. However, this pulverized coal combustion furnace also has the same problem as the use of pulverized coal in blast furnace operation.

In blowing pulverized coal, pulverized coal is produced by dry pulverization of raw coal, classification, storage / discharge in a hopper,
Follow the steps of gas transportation through piping, blowing into the metallurgical furnace or combustion furnace from the blowing port, and combustion within the metallurgical furnace or combustion furnace.The discharge of pulverized coal from the hopper and gas transportation through piping are as follows. There is a problem.

That is, the basic physical properties of the powder such as the fluidity of the pulverized coal change depending on the coal type, particle size, and water content of the pulverized coal to be discharged / transported, so that the discharge / transport situation greatly changes. For this reason, if the basic physical properties of pulverized coal are out of the optimum range, suspending and blowing through the hopper with a hopper,
This may cause pipe blockage during gas transportation, and it is difficult to continue stable pulverized coal injection for a long period of time.

In order to solve such a problem, it is considered to improve the transportability of pulverized coal, and various methods have been proposed in the past. For example, char in pulverized coal 5-20
% Mixing (Japanese Patent Laid-Open No. 4-268004), inert in coal (MICLINIT prescribed by JIS M8816-1979,
Finely pulverized after adjusting the amount of components (total of 1/3 semi-fujinit, fujinit and minerals)
9518, JP-A-5-25516, JP-A-5-2224
No. 15), the coal type of the pulverized coal to be blown is limited so that it is equal to or higher than the reference value of the blast furnace using the fluidity index (JP-A-4-224610), and the friction coefficient between the pulverized coal and the pipe is adjusted ( JP-A-5-214417) and controlling the water content in the pulverized coal to an appropriate value (JP-A-5-78675). Further, as a method for improving the pulverization efficiency of pulverized coal, a method of adsorbing a dispersant (JP-A-63-22).
No. 4744), but this method does not mention the transportability of pulverized coal.

[0007]

However, in the above-mentioned method, the kinds of coal that can be used for blowing pulverized coal are limited, the hanging and blowing through of the hopper in the hopper, and the clogging of the pipe are not sufficiently solved, and the control is not possible. However, there is a problem in that the equipment and facilities are expensive, and a method that is practically satisfactory is not provided.

Further, for example, in the current method of operating a blast furnace,
The amount of pulverized coal blown from the blowing port is about 50 to 250 kg / pig of pig iron, but it is desirable to further increase the amount of pulverized coal blown from the viewpoint of cost. However, since the pulverized coal is not always sufficiently conveyed by the above method, it is not possible to significantly improve the blowing amount of the pulverized coal.

Therefore, the object of the present invention is to solve the above-mentioned problems in the conventional method and to improve the transportability of pulverized coal.
The purpose is to remove restrictions on coal types, prevent pipe blockages and hanging in hoppers, and enable stable large-scale injection of pulverized coal.

[0010]

Means for Solving the Problems As a result of intensive studies aimed at achieving the above object, the present inventors have found that an organic compound having a polar group and substantially soluble in water has an average HGI of 30 or more in raw coal. It has been found that the transportability of such pulverized coal is dramatically improved by impregnating it with the pulverized coal of No. 3, and has completed the present invention.

That is, the present invention is composed of an organic compound having a polar group and substantially soluble in water, and the average HGI of raw coal is
The present invention provides a pulverized coal transportability improving agent characterized by being used for 30 or more dried pulverized coals, and a pulverized coal comprising the transportability improving agent and fine pulverized coals. Also,
The present invention provides a method for operating a metallurgical furnace or a combustion furnace using such a transportability improver and fine pulverized coal.

The term "water-soluble organic compound" as used herein means that a 10-fold amount (weight basis) of water (10
(Ion-exchanged water at ℃) does not cause cloudiness, and
The amount of organic compounds remaining on the filter when filtered through a 0.1 μm membrane filter is 10% by weight or less of the amount of organic compounds used in the test.

A method of operating a metallurgical furnace or a combustion furnace using the transportability improver of the present invention is 0.01% by weight or more and 10% by weight or more with respect to the pulverized coal blown from the blowing port of the metallurgical furnace or the combustion furnace.
Below, preferably from 0.05% by weight or more to improve transportability 5
It is characterized in that a transportability improver of not more than wt% is added to the pulverized coal to reduce the triboelectric charge amount of the pulverized coal, and the pulverized coal is blown from a blowing port of a metallurgical furnace or a combustion furnace. It is preferable that the addition amount to the pulverized coal is 0.01% by weight or more from the viewpoint of the effect of improving the transportability, and even if the addition amount exceeds 10% by weight, the effect corresponding to the addition amount is not improved and it is economically disadvantageous Become.

The pulverized coal to which the present invention is applied is dry pulverized coal having an average HGI of raw coal of 30 or more. here,
The term "dried" means that the amount of water is 10% by weight or less according to the dry weight loss measurement method defined in JIS M 8812-1984. Pulverized coal with a high water content is not suitable as a fuel for blowing in a metallurgical furnace or a combustion furnace.

Although pulverized coal having an average HGI of 30 or more of such raw coal has poor transportability, use of the transportability improver of the present invention enables smooth transportation of such pulverized coal. Furthermore, the present invention is also effective for pulverized coal having an average HGI50 of 50 or higher for raw coal, which is considered to be extremely difficult to transport by gas using the present technology.

Here, "HGI" means "Hardgro"
ve Grinding Index ”(grinding power index)
Which is an index of coal crushing resistance defined in ASTM D409.

As a result of studies by the present inventors, it was clarified that the above-mentioned problem of pulverized coal was caused by electrification between pulverized coals, and the above-mentioned problems were solved by reducing the triboelectric charge amount of the pulverized coal. It was found that the pulverized coal itself has a fluidity index,
It was found to be strongly correlated with the pipe transportation characteristics.

That is, in coal having poor transportability, a large amount of fine coal adheres around the pulverized coal having an average particle size, and in pulverized coal having good transportability, most of the fine coal adheres around. Not not. When these finer coals adhere strongly to normal pulverized coal, the apparent shape of pulverized coal becomes distorted.The finer coal adhered to one pulverized coal adheres strongly to other pulverized coal. The fluidity of pulverized coal deteriorates because it acts like a binder. The force between these finer coals and normal pulverized coal is due to the Coulomb attractive force.
By measuring the triboelectric charge between pulverized coals of m or less by the blow-off method (usually the blow-off method is used to measure the triboelectric charge between different substances having different particle size distributions, for example, toner and carrier). I was able to confirm. Also, the amount of triboelectric charge reduction is [average HGI of raw coal] x 0.00
It was found that the pulverized coal had an improved transportability if it was 7 μC / g or more. Furthermore, the triboelectric charge of the original pulverized coal is 2.8μ.
In the case of pulverized coal with more than C / g and very poor transportability, the triboelectrification amount is 2.8 μC by adding a transportability improver.
/ G or less, the transportability could be improved. In addition,
In the present invention, the triboelectric charge amount means a value measured by the method described in detail in Examples below.

As an index of the transportability of the pulverized coal, the fluidity index and the pressure loss in the pipe transportation test described in detail in Examples described later were used. The fluidity index can simulate discharge characteristics in a hopper and the like, and the pressure loss can simulate flow characteristics in a pipe during gas transportation. To improve transportability, it is necessary to improve the fluidity index by 3 points or more and reduce the pressure loss by 3 mmH ₂ O / m or more. For pulverized coal, which has extremely poor transportability, the fluidity index must be 40 or more and the pressure loss must be 16 mmH ₂ O / m or less.

Therefore, as a result of further study by the present inventors, as a compound that reduces the triboelectric charge amount of such pulverized coal and improves the transportability of pulverized coal, it has a polar group and is substantially soluble in water. It was found that the organic compounds of

The transportability improver of the present invention reduces the triboelectric charge amount of pulverized coal, and has carboxylic acid, sulfonic acid or salts thereof, amide, sulfate or salt thereof, amine salt, nitrile in the molecule. , Having at least one polar group such as a phenol group or a salt thereof.

Particularly, the transportability improver preferably used in the present invention is one or more selected from anionic surfactants, cationic surfactants, amphoteric surfactants, lower fatty acids and lower fatty acid salts. Is mentioned.

It is preferable to use these as they are, or to dissolve them in a solvent at an appropriate concentration and make them in a liquid state for uniform dispersion. In that case, a concentration of 1% by weight or more is convenient for drying the solvent. The solvent is preferably water in terms of handling dryness.

Further, the time for adding the transportability improver of the present invention is similarly effective before and after pulverization of raw coal.

Specific examples of the compounds exemplified above as the transportability improver used in the present invention are shown below.

Examples of (A) anionic surfactants, cationic surfactants and amphoteric surfactants include the following.

[0027]

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2. Alkyl ether carboxylates _{RO (CH 2 CH 2 O)} n CH 2 COOM _{[R: C 6 ~C 20, M} : H, Na, K, NH 4, or an organic amine salt, n: 0 to 40] 3. 3. Lignin sulfonate Lignin sulfonate sodium salt, calcium salt, potassium salt, ammonium salt, triethanolamine salt, etc. 4. Acylated peptides RCO (NHR'CO) _n OM _{[R, R ': C 6 ~C} 20, M: H, Na, K, NH 4, or an organic amine salt, n: 1 to 40]

[0029]

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[0030]

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[0031]

[Chemical 4]

11. Sulfated oil Roth oil (low-sulfated castor oil), low-sulfated olive oil, sulfated beef tallow, sulfated peanut oil 12. Higher alcohol sulfate ester salt RSO ₃ M [R: C ₆ -C] ₂₀ , M: H, Na, K, NH ₄ , organic amine salts, etc.]

[0033]

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14. Alkyl ether sulfate R (OCH ₂ CH ₂ ) _n OSO ₃ M [R: C _{6 to} C ₂₀ , M: H, Na, K, NH ₄ , organic amine salt, etc., n: 0 to 40 ]

[0035]

[Chemical 6]

[0036]

[Chemical 7]

18. Fatty acid alkylol amide sulfate salt RCONHCH ₂ CH ₂ OSO ₃ M [R: C _{6 to} C ₂₀ , M: H, Na, K, NH ₄ , organic amine salt, etc.]

[0038]

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[0039]

[Chemical 9]

21. Molecular weight 10 obtained from the following (1) and (2)
100 to 100,000 (co) polymer (1) α, β-unsaturated carboxylic acid or salt thereof, sulfonic acid group-containing vinyl compound or salt thereof (2) acrylonitrile, vinylpyrrolidone and carbon number 2
To 20 aliphatic olefins (i) One or more polymers or copolymers selected from (1) (b) One or more compounds selected from (1) and selected from (2) One or more copolymers. Examples of the vinyl-based monomer as a raw material of this copolymer include vinylpyrrolidone, acrylonitrile; acrylic acid, methacrylic acid, maleic acid or alkali metal salts or ammonium salts of these acids; vinylsulfonic acid, methallylsulfonic acid. , 2-acrylamido-2-methylpropanesulfonic acid, styrenesulfonic acid, alkali metal salts or ammonium salts of these acids, and the like.

22. One or more compounds selected from naphthalenesulfonic acid or a salt thereof, melaminesulfonic acid or a salt thereof, phenolsulfonic acid or a salt thereof, ligninsulfonic acid or a salt thereof, and an average of an aliphatic aldehyde. Condensate with a molecular weight of 1,000 to 100,000. Examples of the salt include alkali metal salts and ammonium salts.

23. Aliphatic amine salt-Primary amine RNH ₂ X [R: C _{6 to} C ₂₀ , X: inorganic acid, organic acid]

[0043]

[Chemical 10]

[0044]

[Chemical 11]

[0045]

[Chemical 12]

29. A homopolymer of a nitrogen-containing monomer represented by the following general formulas (I) to (IX) or a salt thereof, or a copolymer compound of two or more kinds thereof.

[0047]

[Chemical 13]

[0048]

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[0049]

[Chemical 15]

Specific examples of these monomers include the following. That is, as an example of the formula (I), 3-methacryloxy-2-hydroxypropyldimethylamine, 3
-Methacryloxy-2-hydroxypropylethylmethylamine, 3-methacryloxy-2-hydroxypropyldiethylamine, 3-methacryloxy-2-hydroxypropyldipropylamine and the like; examples of formula (II) include N, N-dimethylamino Methylene capped ethylene glycol methacrylate, N, N-dimethylamino propylene capped ethylene glycol methacrylate, N, N-dimethylamino methylene capped diethylene glycol methacrylate, N, N-dimethylamino ethylene capped diethylene glycol methacrylate, N, N-dimethylamino Propylene-capped diethylene glycol methacrylate, N, N-diethylaminomethylene-capped ethylene glycol methacrylate, N, N- Ethylamino ethylene capped ethylene glycol methacrylate, N, N-diethylamino propylene capped ethylene glycol methacrylate, N, N-diethylamino methylene capped diethylene glycol methacrylate, N, N-diethylamino ethylene capped diethylene glycol methacrylate, N, N-diethylamino propylene cap Dodiethylene glycol methacrylate and the like; examples of the formula (III) are N-2-hydroxymethyl-2-α-methylvinylimidazole and N-2-hydroxyethyl-2.
-Α-methylvinylimidazole, N-2-hydroxypropyl-2-α-methylvinylimidazole and the like;
Examples of the formula (IV) include N, N-dimethylmethyleneimine methacrylamide, N, N-dimethylethyleneimine methacrylamide, N, N-dimethyldimethyleneimine methacrylamide, N, N-dimethyldiethyleneimine methacrylamide, Examples of the formula (V) include N, N-diethylmethyleneimine methacrylamide, N, N-diethylethyleneimine methacrylamide, N, N-diethyldimethyleneimine methacrylamide, and N, N-diethyldiethyleneimine methacrylamide. Is N, N-dimethylaminoethyl acrylate, N,
N-diethylaminoethyl acrylate, N, N-dimethylaminoethyl methacrylate, N, N-diethylaminoethyl methacrylate, N, N-dimethylaminopropyl acrylamide, N, N-diethylaminopropyl acrylamide, N, N-diethylaminopropyl methacrylamide, etc. Examples of the formula (VI) include N, N-dimethylaminoethylethylene, N, N-diethylaminomethylethylene, N, N-dimethylaminomethylpropene, N, N-diethylaminomethylpropene and the like; (VI
Examples of the formula (I) include vinylpyridine and the like; examples of the formula (VIII) include vinylpiperidine and vinyl-N-methylpiperidine and the like; examples of the formula (IX) include vinylbenzylamine and vinyl-N, N. -Dimethylbenzylamine and the like.

30. α, β-Unsaturated carboxylic acid, its salt or its derivative, sulfonic acid group-containing vinyl compound or its salt, acrylonitrile, vinylpyrrolidone and carbon number 2
~ 20 one or more vinyl-based monomers selected from the group consisting of aliphatic olefins and the above formulas (I) to (IX)
A copolymer with a nitrogen-containing monomer represented by or one or more salts thereof. Examples of the vinyl-based monomer as a raw material of this copolymer include vinylpyrrolidone, acrylonitrile; acrylic acid, methacrylic acid, maleic acid or alkali metal salts, ammonium salts, amide compounds or esterified products of these acids; vinyl sulfone. Examples thereof include acids, methallylsulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, p-styrenesulfonic acid, alkali metal salts or ammonium salts of these acids, and the like.

31. Ring-opening polymers of ethyleneimine, salts thereof, quaternary ammonium salts thereof or derivatives thereof. As a specific example thereof, for example, the repeating unit is represented by the following general formula (X), and the average molecular weight is 1,000 to 1,000,000.
The following are listed.

[0053]

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32. A polycondensation product of an aliphatic dicarboxylic acid and polyethylene polyamine or dipolyoxyethylene alkylamine, a salt thereof or a quaternary ammonium salt thereof, specifically, for example, a repeating unit thereof is represented by the general formula ( XI) a polycondensation product of a polyethylene polyamine and an aliphatic dicarboxylic acid or a polycondensation product of a dipolyoxyethylene alkylamine represented by the general formula (XII) and an aliphatic dicarboxylic acid having a molecular weight of 1,000 to 1,000,000. The following are listed.

[0055]

[Chemical 17]

33. Dihaloalkane-polyalkylenepolyamine polycondensation product, salt thereof or quaternary ammonium salt thereof. Specific examples thereof include dibenzo compounds such as 1,2-dichloroethane, 1,2-dibromoethane and 1,3-dichloropropane. A quaternary ammonium salt of a polycondensation product of a haloalkane and a polyalkylenepolyamine having two or more tertiary amino groups in the molecule, having an average molecular weight of 1,000 to 1,000,
There are 000. Examples of the polyalkylene polyamine used here include tetramethylethylenediamine, tetramethylpropylenediamine, pentamethyldiethylenetriamine, hexamethylenetetramine, triethylenediamine, and the like.

34. Epihalohydrin-amine polycondensation product,
Specific examples of the salt or the quaternary ammonium salt include those having a repeating unit represented by the following formula (XIII) and an average molecular weight of 1,000 to 1,000,000.

[0058]

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35. Chitosan salt or starch or cellulose or a cation-modified product thereof.

[0060]

[Chemical 19]

37. Aminocarboxylate RNH (CH ₂ ) _n COOM [R: C _{6 to} C ₂₀ , n: 1 to 2, M: H, Na, K, NH ₄ ,
Organic amine salts, etc.)

[0062]

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39. Lecithin Among these surfactants, those having 3, 21, 22, 29 to 35 are particularly effective.

The lower fatty acid (B) has 1 to 8 carbon atoms.
Examples of the monovalent or divalent fatty acids include, for example, formic acid, acetic acid, propionic acid, oxalic acid, malonic acid, succinic acid, adipic acid, maleic acid and caproic acid. The lower fatty acid salts include formic acid, acetic acid, propionic acid, oxalic acid, malonic acid, succinic acid, adipic acid,
Examples thereof include sodium, potassium and ammonium salts such as maleic acid and caproic acid.

As a metallurgical furnace and a combustion furnace to which the present invention is applied, a furnace using pulverized coal as a fuel and / or a reducing agent (blast furnace, cupola, rotary kiln, smelting reduction furnace, cold iron source melting furnace, boiler, etc.) And a carbonization device using pulverized coal (for example, fluidized bed carbonization furnace, gas reforming furnace, etc.).

[0066]

EFFECTS OF THE INVENTION According to the present invention, by reducing the triboelectric charge amount of pulverized coal, the transportability of pulverized coal having an average HGI of 30 or more of raw coal is improved, and a large amount of such pulverized coal can be transported. . Further, by adding the transportability improver of the present invention to coal having poor transportability, the transportability can be improved and a large amount can be transported, so that the types of coal that can be used for blowing pulverized coal can be expanded.

At the same time, since the pulverized coal to be blown from the blowing port treated with the transportability improving agent of the present invention has a good fluidity, it is also possible to prevent hanging in the hopper, and further, from the hopper. It is possible to greatly reduce the temporal change in the cutout amount and the deviation of the distribution amount.

[0068]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

Examples 1 to 88 and Comparative Examples 1 to 7 [1] Crushing of Raw Coal and Preparation of Pulverized Coal for Evaluation The crushing of raw coal and the addition of the transportability improver were carried out by the following procedure. The raw coal and the transportability improver shown in Tables 1 to 9 are put into a crusher [Small crusher SCM-40A (manufactured by Ishizaki Denki Seisakusho)], crushed and mixed, and adjusted with a crushing time to obtain the required particle size. . At that time, the transportability improver was dissolved in the solvents shown in Tables 1 to 9,
The raw coal is pulverized and added so that the amount added to the pulverized coal is the amount shown in the table. It is dried at 105 ℃ for 1 hour, and the water content in the pulverized coal is 0.5 to 1.0.
Adjust to be%. It was passed through a 106 μm sieve to obtain pulverized coal having a particle size of 106 μm or less. The water content (0.5 to 1.0%) and volume average particle diameter (75 μm) in the pulverized coal were all adjusted to be the same. Here, the volume average particle diameter is defined by the following equation.

[0070]

[Equation 1]

[2] Evaluation of pulverized coal The pulverized coal thus obtained was subjected to triboelectric charging, fluidity index, and
The effect of additives on the pipe transportation properties was investigated by the following method.

<Method of Measuring Triboelectrification Amount> The triboelectrification amount of pulverized pulverized coal is measured by a blow-off measuring device as shown in FIG. In FIG. 1, 1 is a compressed gas, 2 is a nozzle, 3 is a Faraday gauge, 4 is a mesh having an opening of 38 μm, 5 is a dust hole, and 6 is an electrometer. Such a blow-off device is usually used for measuring the triboelectric charge amount between different substances having different particle sizes (for example, toner and carrier), but in the present invention, the mesh has a mesh size of 38 μm.
m mesh is used, 0.1-0.3g of pulverized coal is placed on it, and compressed gas (for example, air) is placed at 0.6kgf / cm ²
The amount of triboelectrification of pulverized coal of 38 μm or less is measured by spraying at a pressure of 3 μm and blowing out pulverized coal of 38 μm or less to the dust hole to remove it.

<Flowability Index Measuring Method> The fluidity index is an index for evaluating the fluidity of the powder, and the four factors of the powder (repose angle, compressibility, spatula angle, cohesion degree) are indexes. It is obtained from the sum of each index. For details on the measurement method and index of each factor, refer to 151 of “Powder Engineering Handbook” (edited by Japan Society of Powder Engineering, published by Nikkan Kogyo in 1987).
~ Page 152. In addition, the measuring method of each factor is described below. 1. Angle of repose: The powder is passed through a standard sieve (25 mesh) and further injected through a funnel onto a disk having a diameter of 8 mm, and the inclination angle of the formed sedimentary layer is measured. 2. Compressibility: Cylindrical container for filling powder (volume 100c
m ³ ), the bulk density ρ _s (g / c
m ³ ) and the dense packing density ρ _c (g / cm ³ ) after tapping is performed a certain number of times (180 times), the compression degree ψ (%) is calculated by the following formula. ψ = (ρ _c −ρ _s ) × 100 / ρ _c (%) 3. Spatula angle: A spatula (spatula) with a constant width (22 mm) is inserted into the accumulated powder, and the spatula is lifted and the inclination angle of the powder placed on the spatula is measured. Next, a slight impact is applied to the spatula, this angle is measured again, and the average value of these two is taken as the spatula angle. 4. Cohesion degree: Three kinds of sieves with different openings (60, 100, 200 mesh from each upper sieve) are piled up, 2 g of powder is placed on the uppermost row, and then these are vibrated at the same time, and left on each sieve after vibration is stopped. Weighing the amount of powder, (amount of powder in the upper sieve / 2g) × 100, (amount of powder in the intermediate sieve / 2g) × 100 × 3/5, and (amount of powder in the lower sieve / 2g) ) × 100 × 1/5 is calculated by summing the three calculated values. Incidentally, in the case of pulverized coal as used in the present invention, there is no difference in the amount of pulverized coal remaining in each sieve, it is difficult to calculate the cohesion, in the present invention, the angle of repose, the degree of compression, the spatula angle of The liquidity index was evaluated from the three total points.

<Piping Transport Characteristic Measuring Method> “CAMP-I
SIJ Vol. 6 ”(1993), page 91, in accordance with the method described in detail, the pipe transportation characteristics were evaluated by measuring the pressure loss with the apparatus of FIG. In FIG. 2, 7 is pulverized coal, 8 is a table feeder, 9 is a flow meter, and 10 is a pipe diameter 1.
2.7mm horizontal tube, 11 means cyclone. This device measures the pressure loss between the pressure measurement holes (P ₁ , P ₂ ) by transporting the pulverized coal 7 discharged from the powder feeder 8 by a carrier gas. The experimental conditions were as follows. Pulverized coal supply rate 0.8 kg / min Carrier gas Nitrogen (N ₂ ) Carrier gas amount 4 Nm ³ / h (67 liters / min) Transport time 6 minutes Evaluation is as follows. 1. Pressure Loss The pressure gauges P ₁ and P ₂ sample data at 500 Hz. The pressure loss is P ₁ during the transportation time (6 minutes).
Given by the overall average of P ₂ .

[0075]

[Equation 2]

The results are shown in Tables 1-9.

[0077]

[Table 1]

[0078]

[Table 2]

[0079]

[Table 3]

[0080]

[Table 4]

[0081]

[Table 5]

[0082]

[Table 6]

[0083]

[Table 7]

[0084]

[Table 8]

[0085]

[Table 9]

The same evaluation as above was carried out using the following compounds. The results are shown in Tables 10-13.

(A) Phosphate of diethylaminomethylmethacrylate polymer (Mw = 10,000) (B-1) Borate of diethylaminoethylmethacrylate / vinylpyrrolidone / sodium acrylate = 5/4/1
(Indicated by molar ratio; the same applies hereinafter) which is a copolymer (Mw = 20
10,000) (B-2) 〃 (Mw = 50,000) (B-3) 〃 (Mw = 5000) (B-4) 〃 (Mw = 1500) (C) Diethylaminoethyl methacrylate phosphate / sodium methacrylate = 4/5 copolymer (Mw = 20,000) (D) Ring-opening polymer of ethyleneimine phosphate (Mw = 10)
(E) Ethyl phosphinic acid salt of dimethylaminoethyl methacrylate / sodium acrylate = 3/1 copolymer (Mw = 300,000) (F) Ethylphosphonic acid salt of dimethylaminoethyl methacrylate / 2-acrylamino Copolymer of sodium 2-methylpropanesulfonate = 4/1 (Mw = 100,000) (G) Phosphate of vinylpyridine / vinylpyrrolidone /
Copolymer of sodium acrylate = 6/3/1 (Mw = 450,000) (H) Polycondensate of diethylenetriamine thiophosphate and dimer acid (Mw = 800,000) (I) Phosphoric acid of diethylaminoethylmethacrylamide Salt / sodium acrylate / sodium vinyl sulfonate = 3 /
1/1 copolymer (Mw = 400,000) (J) quaternary ammonium salt of vinylpyridine with dimethylphosphinic acid / vinylpyrrolidone / sodium acrylate = 6/3/1 copolymer (Mw = 450,000) (K) Phosphate of phosphate of diethylaminoethylmethacrylamide of (I) above (L) Quaternary ammonium salt of cationized cellulose (Mw = 1 million) (M) 1,2-dichloroethane Hexamethylenetetramine phosphate polycondensate (Mw = 50,000) (N) Diethylenetriamine ethylphosphinate polydimerate (Mw = 800,000) (O) Epichlorohydrin trimethylamine quaternary ammonium compound Ring-opening polymer of phosphite (Mw = 10
10,000) (P) Polycondensation product of quaternary ammonium salt of tetramethylpropylenediamine with diethylphosphonic acid (Mw = 10
(Q) The vinylpyridine phosphate of (G) above is used as a sulfate (R) The diethylenetriamine thiophosphate of (H) above is used as a nitrate (S) Dimethylamino of (F) above Ethyl methacrylate ethylphosphonate as hydrochloride (T) Dimethylaminoethyl methacrylate ethyl phosphinate as glycolate (E) above (U) Ethyleneimine phosphorus as (D) above (V) Quaternary ammonium salt of vinylpyridine with dimethyl sulfate / vinylpyrrolidone / sodium acrylate = 6
/ 3/1 copolymer (Mw = 450,000) (Y) Na salt of N-1 dimethylsulfoethylacrylamide homopolymer (Mw = 70,000) (Z) N-1 N-1 dimethylsulfoethylacrylamide
Copolymer of a salt / dimethylaminoethyl methacrylate phosphate = 1/1 (Mw = 20,000) (AA) Phosphonate of polyethyleneimide (Mw = 6)
10,000) / dimethylaminoethylmethacrylate ethylphosphinate = 1/1 (Mw = 60,000) mixture (BB) 3-methacryloxy-2-hydroxypropyltrimethylammonium phosphate / dimethylaminoethylmethacrylate ethylphosphinic acid Salt = 2/1 copolymer (Mw = 50,000) (CC) Methacryldimethylaminoethyl ethoxylate phosphonate (Mw = 80,000) / polyethyleneimine (Mw = 80,000) = 1/1 mixture ( DD) Quaternary ammonium salt of cationized starch

[0088]

[Table 10]

[0089]

[Table 11]

[0090]

[Table 12]

[0091]

[Table 13]

Example 89 An example of application to a blast furnace pulverized coal blowing device is shown below. Condition Pulverized coal injection rate: 40 t / Hr Transportability improver: β-naphthalenesulfonic acid formalin condensate addition amount: 0 or 0.3 wt% Pulverized coal: Volume average particle size… 74 μm Water content… 1.5% Average of raw coal HGI ... 45, 55, 70 FIG. 3 shows a schematic view of the blast furnace pulverized coal blowing device used in this example. In FIG. 3, 12 is a blast furnace, 13 is a blowing port, 14 is a blowing pipe, 15 is a distribution tank, 16 is a valve, 17 is a pressure equalizing tank,
18 is a valve, 19 is a pulverized coal storage tank, 20 is a coal crusher,
21 is an additive spray nozzle, 22 is a coal conveyor belt conveyor,
23 is a coal receiving hopper and 24 is an air / nitrogen compressor.

The coal is put into the receiving hopper 23 and supplied to the crusher 20 by the conveyor 22. On the way, a transportability improver is spray-added from the nozzle 21. The pulverizer 20 pulverizes the coal into pulverized coal having the above particle size, and sends the pulverized coal to the storage tank 19. First, the valve 18 is opened in a state where the internal pressure of the pressure equalizing tank 17 is equal to the atmospheric pressure, and a specified amount of pulverized coal is supplied from the storage tank 19 to the pressure equalizing tank 17. Next, the internal pressure of the pressure equalizing tank 17 is increased to the same internal pressure as that of the distribution tank 15. With the internal pressures of tanks 15 and 17 equal, valve 16 opens and pulverized coal falls by gravity. The pulverized coal is gas-transported from the distribution tank 15 to the blowing port 13 through the blowing pipe 14 by the blowing air supplied from the compressor 24, and is blown into the blast furnace 12 from the blowing port 13.

<Effect of Addition of Transportability Improving Agent> When the pulverized coal is transported under the above conditions, the tank transfer time depending on the presence or absence of the addition of the transportability improving agent (the pulverized coal is transferred from tank 17 to tank 15 Time) and the pipe pressure loss (pressure loss in the blow pipe 14, that is, the differential pressure between the tank 15 and the blast furnace 12) were evaluated. The results are shown in FIGS. 4, 5 and 6. Figures 4 and 5
In the figure, (a) means the case where the transportability improver is not added, (b) means the case where the transportability improver is added, and in FIG. 6, A means the upper limit value of the equipment.

When raw coal having an average HGI of 45 was used, the pipe pressure loss and the tank transfer time were reduced as shown in FIGS. 4 and 5, and the amount of pulverized coal injected could be increased in the same apparatus. Also, a simpler device is required to obtain the same blowing ability. Note that FIGS. 4 and 5 are relative evaluations in which the case where the transportability improver is not added is set to 1.

FIG. 6 shows changes in pipe pressure loss when the average HGI of raw coal was changed to 45, 55 and 70. Even if high HGI coal is used, the pipe pressure loss becomes less than the facility upper limit by the addition of the transportability improver, the coal types of the coal used can be expanded, and inexpensive coal can be used. In addition, FIG. 6 is a relative evaluation with 1 when the transportability improver is not added to pulverized coal having an average HGI of 45.

Example 90 An application example to a pulverized coal burning boiler is shown below. Additive: β-naphthalenesulfonic acid formalin condensate Addition amount: 0 or 0.3 wt% Pulverized coal: Volume average particle size… 74 μm Water content… 1.5% Average HGI of raw coal… 45, 55, 65, 75 In this example A schematic view of the pulverized coal burning boiler used is shown in FIG. 7. In FIG. 7, 25 is a boiler combustion chamber, 26 is a burner, 27 is a blowing pipe, 28 is a pulverized coal storage tank, 29 is a coal crusher, 30 is an additive spray nozzle, 31 is a coal conveyor belt conveyor, and 32 is coal receiving. Hopper 33 is an air / nitrogen compressor.

The coal is put into the receiving hopper 33 and supplied to the crusher 29 by the conveyor 31. On the way, a transportability improver is spray-added from the nozzle 30. The crusher 29 crushes the coal into pulverized coal having the above particle size and sends it to the storage tank 28. Next, the air is conveyed by the blown air supplied from the compressor 33, is supplied to the burner 26, and is burned.

<Effect of Addition of Transportability Improving Agent> When pulverized coal is conveyed under the above conditions, pipe pressure loss (pressure loss in the blowing pipe 27, that is, tank
The change in differential pressure between 28 and burner 26) was evaluated. The result is shown in FIG. 8, where A means the value of the equipment upper limit,
× means that the pipe was blocked. In addition, FIG. 8 is a relative evaluation with 1 being the case where the transportability improver is not added to pulverized coal having an average HGI of 45 of raw coal.

When the average HGI of raw coal was changed to 45, 55, 65, and 75, the pipe pressure loss was below the upper limit of the equipment even when high HGI coal was used due to the addition of the transportability improver, and the coal types used could be expanded.

Examples 91 to 102 and Comparative Examples 8 to 15 Evaluations similar to those of Examples 1 to 88 and Comparative Examples 1 to 7 were performed using the transportability improvers shown in Tables 14 to 16. In addition, it is also shown how much the fluidity index, the pressure loss, and the triboelectric charge amount increased or decreased with respect to Comparative Examples 8 to 11 in which the transportability improver was not added. That is, based on Comparative Examples 8 to 11, it was shown in each raw coal how much the fluidity index was increased and the pressure loss or the triboelectric charge amount was decreased by the addition of the transportability improver ( For example, Comparative Example 5,
Example 91, Example 95 and Example 99 are based on the value of Comparative Example 8).

[0102]

[Table 14]

[0103]

[Table 15]

[0104]

[Table 16]

[Brief description of drawings]

FIG. 1 is a schematic view of an apparatus used for measuring a triboelectric charge amount.

FIG. 2 is a schematic diagram of an apparatus used for measuring pipe transportation characteristics.

FIG. 3 is a schematic diagram of an actual blast furnace pulverized coal injection device used in Example 89.

FIG. 4 is a chart showing results of transfer time in Example 89.

FIG. 5 is a chart showing the results of pipe pressure loss in Example 89.

FIG. 6 is a chart showing the results of pipe pressure loss in Example 89.

FIG. 7 is a schematic view of a pulverized coal burning boiler used in Example 90.

FIG. 8 is a chart showing results of pipe pressure loss in Example 90.

FIG. 9: Average H of raw coal when various transportability improvers were used
Chart showing the relationship between GI and triboelectric charge amount

[Explanation of symbols]

 1: Compressed gas 2: Nozzle 3: Faraday gauge 4: Mesh 5: Dust hole 6: Electrometer 7: Pulverized coal 8: Table feeder 9: Flow meter 10: Horizontal pipe 11: Cyclone 12: Blast furnace 25: Boiler combustion chamber 26 :burner

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenichi Miyamoto 300-56 Kirei, Wakayama City, Wakayama Prefecture (72) Inventor Takashi Matoba 1-7-9 Wakauranishi, Wakayama City, Wakayama Prefecture (72) Takehiko Ichimoto Wakayama 136-16 Enohara, Wakayama, Japan

Claims (21)

[Claims] 1. A pulverized coal transportability improver comprising a polar group and a substantially water-soluble organic compound, which is used for dry pulverized coal having an average HGI of raw coal of 30 or more. . 2. The reduction amount of the triboelectric charge amount of the pulverized coal when 0.3% by weight (converted to dry coal) is added to the pulverized coal is [average HGI of raw coal] × 0.007 μC / g or more. The pulverized coal transportability improving agent according to claim 1. 3. The triboelectric charge amount of the pulverized coal is 2.8 μC when 0.3% by weight (converted to dry coal) is added to the pulverized coal.
/ G or less, the pulverized coal transportability improving agent according to claim 2. 4. The organic compound according to claim 1, wherein the organic compound is one kind or two or more kinds of organic compounds selected from anionic surfactants, cationic surfactants and amphoteric surfactants. Pulverized coal transportability improver. 5. The pulverized coal transportability improving agent according to claim 1, wherein the organic compound is one or more organic compounds selected from lower fatty acids or salts thereof. 6. An improved transportability of pulverized coal, characterized in that a substantially water-soluble organic compound having a polar group is attached to the surface of dry pulverized coal having an average HGI of raw coal of 30 or more. Method. 7. The organic compound to the pulverized coal
Add 0.01 wt% or more and 10 wt% or less and decrease the triboelectric charge amount of the pulverized coal by [average HGI of raw coal] × 0.007 μC
/ G or more, The pulverized coal transportability improving method according to claim 6, characterized in that. 8. The organic compound relative to the pulverized coal is 0.
The method for improving the transportability of pulverized coal according to claim 7, wherein the amount of triboelectricity of the pulverized coal is adjusted to 2.8 µC / g or less by adding at least 01% by weight and not more than 10% by weight. 9. The organic compound is one or more organic compounds selected from anionic surfactants, cationic surfactants and amphoteric surfactants.
The method for improving the transportability of pulverized coal according to any one of 1. 10. The method for improving the transportability of pulverized coal according to claim 6, wherein the organic compound is one or more organic compounds selected from lower fatty acids or salts thereof. 11. Dry pulverized coal having an average HGI of 30 or more of raw coal, to which an organic compound having a polar group and substantially soluble in water is attached. 12. The organic compound is deposited in an amount of 0.01% by weight or more and 10% by weight or less, and the reduction amount of triboelectric charge is [average H of raw coal].
GI] × 0.007 μC / g or more, pulverized coal according to claim 11. 13. The pulverized coal according to claim 12, wherein the organic compound is deposited in an amount of 0.01% by weight or more and 10% by weight or less and the triboelectric charge amount is 2.8 μC / g or less. 14. The fine powder according to claim 11, wherein the organic compound is one kind or two or more kinds of organic compounds selected from anionic surfactants, cationic surfactants and amphoteric surfactants. Charcoal. 15. The pulverized coal according to any one of claims 11 to 13, wherein the organic compound is one kind or two or more kinds of organic compounds selected from lower fatty acids or salts thereof. 16. A metallurgical furnace characterized by blowing dry pulverized coal having a polar group and having a substantially water-soluble organic compound attached thereto and an average HGI of raw coal of 30 or more from a blowing port. Operation method of combustion furnace. 17. The method for operating a metallurgical furnace or a combustion furnace according to claim 16, wherein the pulverized coal having the organic compound deposited in an amount of 0.01% by weight or more and 10% by weight or less is blown from a blowing port. 18. The organic compound is deposited in an amount of 0.01% by weight or more and 10% by weight or less, and the reduction amount of triboelectric charge is [average H of raw coal].
The method of operating a metallurgical furnace or a combustion furnace according to claim 16 or 17, characterized in that pulverized coal having a GI] of 0.007 µC / g or more is blown from the blowing port. 19. The metallurgical process according to claim 18, wherein the organic compound is deposited in an amount of 0.01% by weight or more and 10% by weight or less, and pulverized coal having a triboelectric charge amount of 2.8 μC / g or less is blown from a blowing port. Furnace or combustion furnace operating method. 20. The organic compound according to claim 16, which is one kind or two or more kinds of organic compounds selected from anionic surfactants, cationic surfactants and amphoteric surfactants. Metallurgical furnace or combustion furnace operating method. 21. The metallurgical furnace or combustion furnace operating method according to claim 16, wherein the organic compound is one kind or two or more kinds of organic compounds selected from lower fatty acids or salts thereof.