JPS6032891A - Dispersant for aqueous slurry of carbonaceous particulate matter - Google Patents

Abstract

PURPOSE:To provide a dispersant for titled slurry which is of low viscosity and high fluidity, thus capable of pumping, comprising, as the effective component, water-soluble anionic copolymer constituted by specific aromatic sulfonic acid (salt) and copolymerizable aliphatic sulfonic acid (salt). CONSTITUTION:The objective dispersant comprising, as the effective component, a water-soluble anionic copolymer constituted by (A) 20-90mol% of a copolymerizable double bond-contg. aromatic sulfonic acid (salt) and (B) 10-80mol% of a copolymerizable aliphatic unsaturated sulfonic acid (salt). The component (A) is, e.g., (alpha-methyl) styrene sulfonic acid, vinylnaphthalene sulfonic acid. The component (B) is, e.g., olefin sulfonic acid, sulfo group-contg. unsaturated monocarboxylic acid.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field The present invention relates to a dispersant that enables the production of a highly concentrated aqueous slurry of carbonaceous powder that has low viscosity, good fluidity, and can be pumped.

(→Conventional technology) In addition to the remarkable rise in oil prices in recent years, the decline in crude oil reserves and the system's dependence on oil as a key energy source for use in diplomatic strategies have led to oil consumption.

The world is changing from using a wide variety of energy sources, such as coal, nuclear power, natural gas, and hydropower, to take advantage of the advantages of each. In particular, petroleum coke, which is the distillation residue of coal and petroleum, which has traditionally been little used as an energy source, is attracting attention as an important energy source because its price per unit of heat is low and there are many existing technologies that can convert it into energy. However, since coal and petroleum coke are solids, they pose many problems in handling and use such as transportation, storage, and combustion. When these carbonaceous solids are used as fuel, they are usually pulverized to improve combustion speed and combustion efficiency, but handling carbonaceous fine powders poses risks such as generation of public hydrogen and spontaneous combustion, and in the case of coal, In addition, there are many transportation issues that need to be resolved, such as transporting coal from coal mines, unloading it onto rental cars or ships, and loading it to coal storage yards. As a method for solving this transportation problem and reducing handling costs, a method has been proposed in which carbonaceous fine powder is dispersed in a liquid such as water, methanol, or fuel oil, and then transported by pipeline.

Carbonaceous fine powder water slurry, which is made by dispersing carbonaceous fine powder in water, has high practical value because water as a medium is relatively easy to obtain and is very cheap, and there are some methods of transporting coal as a water slurry. It has been put into practical use.

However, this water slurry of carbonaceous fine powder rapidly loses fluidity when the concentration of carbonaceous fine powder is increased and turns into an agglomerate of wet fine powder.
, could not be on. In order to reduce the transportation cost and improve the combustibility of a carbonaceous fine powder water slurry, it is necessary to obtain a carbonaceous one-body water slurry that is highly concentrated and has good fluidity. By adding a surfactant exhibiting a dispersing effect to the aqueous slurry of carbonaceous fine powder, the dispersion state is improved and the concentration of the carbonaceous fine powder can be increased. However, general low-molecular-weight 111 surfactants such as alkylbenzene sulfonates or carboxylic acid-based polymers such as polymethacrylic acid have insufficient performance, and there are differences between the types of carbonaceous fine powders. However, if the solid content concentration exceeds 65 degrees, the fluidity will be extremely reduced, making it impossible to obtain a product suitable for practical use.

C→Object of the Invention The object of the present invention is to improve the fluidity when added to an aqueous slurry of carbonaceous fine powder, and in particular to maintain good fluidity even at a high solid content concentration of 65 coefficients or higher. An object of the present invention is to provide a dispersant that can produce a carbonaceous fine powder aqueous slurry that can be easily mixed.

B) Structure of the Invention The dispersant for an aqueous slurry containing carbonaceous fine powder according to the present invention contains (3) an aromatic nulfonic acid having a copolymerizable double bond or a salt thereof as an active ingredient of the dispersant. 90 molar mass and (B) a copolymerizable aliphatic unsaturated sulfonic acid or its salt 10 to 80 molar mass as constituent monomer components, optionally containing a polyfunctional monomer of 5 molar mass or less. It is characterized by containing a water-soluble anionic copolymer.

(e) Embodiment The carbonaceous fine powder to which the dispersant of the present invention can be applied is not particularly limited as long as it can be used as an energy source, such as brown coal, subbituminous coal, and bituminous coal.

Various types of coal such as anthracite, coke produced from these various types of coal, petroleum coke, car/bin black produced by chemical plants, cargen black obtained by carbonizing organic matter, etc. can be pulverized as needed. Examples include carbonaceous fine powder. The particle size of the carbonaceous fine powder can be used as long as it does not have a particle size of 1 or more, but in general, there is a culm with a small particle size and a M direction that improves the dispersion stability of the carbonaceous fine powder water slurry. Me, Shu/'Ps (approx. 7
4 μ or less) is preferably 50% by weight or more, particularly desirably within the range of 65 to 95% by weight. Aromatic sulfonic acid or its salt (A) and a copolymerizable aliphatic unsaturated sulfonic acid or its salt (B) are the main monomer components, and a polyfunctional monomer (C) is an optional component.
The active ingredient is a water-soluble anionic copolymer containing other copolymerizable monomers.

In order to disperse the carbonaceous fine powder in water, especially at a high concentration, to maintain good stability, and to reduce the viscosity of the slurry and obtain good fluidity, the dispersant contains a compound that adsorbs to the carbonaceous fine powder. It is required to form a water-containing adsorption layer of appropriate thickness on the surface. Therefore, it is important that the dispersant has an appropriate affinity for the carbonaceous powder absorber and an appropriate affinity for water, that is, water solubility. Therefore, the ratio of acid content A in the water-soluble anionic copolymer according to the present invention is 20 to 95%.
A range of molarity is suitable, and a range of 40 to 90 mol is particularly preferred. If the content of component A is less than in this formulation, the affinity between the copolymer and the carbonaceous fine powder will be small;
The effect of the dispersant is insufficient; on the other hand, if the amount is too large, the affinity is too large, which causes it to strongly adsorb to the surface of the carbonaceous fine powder particles, and the thickness of the adsorption layer becomes thinner, so the effect of the dispersant is insufficient. It is not demonstrated. Component B in the copolymer is an essential component that controls the affinity and water solubility for the carbonaceous r=am form of the copolymer, and its proportion is suitably 5 to 80 mol, preferably 10 to 60 mol. It is in the range of moles. The molecular weight of the copolymer used in the present invention is suitably in the range of about 1,000 to 500,000, preferably in the range of about 3,000 to 400,000. In addition, the molecular structure of the copolymer also affects its adsorption state to carbonaceous fine powder, and multi-branched structures tend to be more effective as dispersants because they adsorb more efficiently than linear structures. Therefore, a copolymer containing an optional polyfunctional monomer as a crosslinking component within a range that can maintain water solubility is preferred. The copolymer used in the present invention may be either an acid type or a salt type, but is preferably a salt in which at least half of the sulfonic acid groups are neutralized. The 11 cation present in such a copolymer is lithium.

Alkali metal ions such as sodium and potassium.

Alkaline earth metal ions such as magnesium, calcium, ammonium ions and ammonium ions are suitable, preferably sodium.

Potassium and ammonium ions.

Component A constituting the copolymer used in the present invention is an unsaturated aromatic sulfonic acid or a salt thereof having a copolymerizable double bond and an aromatic nulphonic acid skeleton, and specific examples include styrene nulphonic acid, α- Methylnutylene sulfone 112. Examples include methyl-converted styrene sulfonic acid having a methyl group in the benzene nucleus, vinylnaphthalene sulfonic acid, and salts thereof. Among stiff straws, styrene sulfonic acid and its salts are preferred because of their easy availability. The cation that forms the salt is the same as the cation that makes up the copolymer.

Component B constituting the copolymer used in the present invention is an aliphatic unsaturated nulphonic acid having a copolymerizable double bond or a salt thereof, and includes olefin sulfonic acids such as vinyl sulfonic acid, allyl sulfonic acid, methallyl sulfonic acid, Acrylic acid 2-
Nurpho group-containing monocaloos such as sulfoethyl, 2-sulfoethyl methacrylate, and 3-nulfodelopyl acrylate? acid esters, unsaturated monocarzenic acid amides containing Nurpo groups such as 2-acrylamidoethaneurphonic acid and 2-acrylamide-2-methylpropanesulfonic acid; Includes group-containing allyl ethers and salts thereof. The cations constituting the salt of unsaturated aliphatic sulfonic acid are essentially the same as the cations constituting the water-soluble anionic copolymer. In the copolymer used in the present invention J, a part of component B can be replaced with other copolymerized monomers as long as the performance as a dispersant is not deteriorated.

The copolymer used in the present invention has the above-mentioned components A and B as essential components, and can optionally contain a polyfunctional monomer as component C. Component C acts as a crosslinking agent, changes the molecular structure of the resulting copolymer into a multi-branched one, and increases the average molecular weight, so it is used appropriately in consideration of the molecular structure and average molecular weight.

Component C can be used without particular limitation as long as it is a polyfunctional monomer that is widely used as a crosslinking agent in polymerization reactions. Examples of such monomers include methylene bisacrylamide, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolprono-dimethacrylate, trimethylolprono-dimethacrylate, divinylbenzene, diallyl phthalate, etc. . If the proportion of component C in the copolymer is too large, the water solubility will decrease, resulting in a water-swellable or water-insoluble copolymer; if the proportion is too small, the copolymer will exhibit the same performance as a copolymer that does not contain component C. It becomes like this.

Therefore, the proportion of component C in the copolymer is suitably zero or less than about 5 molar proportions, with p1 preferably between 0.01 and 3 molar proportions.

The dispersant for water slurry of carbonaceous fine powder of the present invention is Afl
Components A and B of f4e are essential components, and if desired, a water-soluble anionic co-composite polymer containing component C as a crosslinking agent is used as an active component, but it can optionally contain a surfactant having dispersion performance. Examples of such surfactants include anionic surfactants such as alkylbenzene sulfonates, dioxyethylene alkyl ether salts, and dioxyethylene alkyl ethers; Examples include nonionic surfactants such as ethylene alkylphenyl ether, lyoxyethylene fatty acid amide, etc. Also, alkylene oxide copolymers, (for example, polyoxyzoro♂lene-polyoxyethylene ether,) 1?lyethyleneimine KeABf
Ropyrene and 6? It is also possible to use a polyether compound having a relatively large molecular weight and having dispersibility, such as a polyether which can be prepared by adding ethylene.

The amount of the optional component having such dispersibility as above is about 100 parts by weight or less, preferably about 60 parts by weight, per 100 parts by weight of the water-soluble anionic copolymer.

The carbonaceous fine powder dispersant for water slurry of the present invention can be in any form such as powder, lump, paste, or liquid depending on the manufacturing, transportation, storage, and usage circumstances.
In particular, he has a good talent.

The carbonaceous fine powder dispersant for water slurry of the present invention has excellent dispersion performance such as dispersion stability and viscosity reduction (improved flow rate properties), so the amount used is slightly lower than that of conventional dispersant for water slurry. This method has the same level of stability and fluidity, and has the advantage of being able to produce a water slurry with a higher concentration than the Ouse method. Therefore, the water slurry of carbonaceous fine powder is
The amount of dispersant used for making gates is 0.05 in the water slurry.
A suitable range is 3,000 to 3,000, preferably 0.1 to 2,000. In addition, if the dispersant of the present invention is used, dispersion stability will be achieved when the concentration of carbonaceous fine powder in the water slurry is close to 80 weight + 3 coefficient, although it will vary depending on the type of carbonaceous fine powder, average particle size, particle size distribution, etc. It is possible to produce products with good viscosity, low viscosity, and good flow ψj1 properties. The zero degree of the carbonaceous fine powder in the water slurry is preferably 60 to 75 degrees.

The order of mixing the carbonaceous fine powder, dispersant, and water is arbitrary, and an appropriate method can be selected depending on whether the carbonaceous fine powder is obtained by dry pulverization or wet pulverization. for example,
For carbonaceous fine powder obtained by the dry grinding method, a dispersant may be dissolved or dispersed in water, the fine powder may be added thereto, and a highly concentrated water slurry may be prepared with a suitable mixing device to a concentration of 3914% fQ. In addition, in the case of 4μ, which uses the wet pulverization method, the water used for wet pulverization is added for a minute: II 1. The agent may be added in advance, or may be added during wet pulverization or after pulverization.

Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples. II of carbonaceous fine powder
! [i and particle size are shown in Table 1, the general properties of the coal used are shown in Table 2, and the copolymer used, 1"11 1'1, is shown in Table 3.

Table 1 Table 2 Example A predetermined amount of dispersant was dissolved in water, and carbonaceous fine powder was added little by little to the predetermined amount (dry basis) in room 1W^. After all additions were completed, the slurry was stirred for 10 minutes at 3000 rpm using a homomixer (manufactured by Tokushu Kikako) to prepare a highly concentrated water slurry of about so op mA, and the viscosity was measured at 25°C.

The measurement results are shown in Tables 4 to 7 together with the types of dispersants. In the table, is ethoxylate a number? It is a lyoxyethylene alkyl ether (the number of carbon atoms in the alkyl group is 12 to 15; the number of individual moles of ethylene oxide is 9). Low viscosity indicates good fluidity.

Experiment A1 is reference data, and the experimental width is 2.3°10.3.
1 and 34 are compared.

It is T money.

Claims (1)

[Claims] As the monomer portion constituting the copolymer, (A) an aromatic sulfonic acid having a copolymerizable double bond or a salt thereof 20-9
A dispersant for an aqueous slurry of carbonaceous fine powder, the active ingredient being a water-soluble anionic copolymer containing 0 molar fraction and (Bl copolymerizable aliphatic unsaturated sulfonic acid or its salt 10 to 80 molar fraction).