JPS58216729A - Dispersing agent for use in coal-water slurry - Google Patents

Abstract

PURPOSE:To obtain a dispersing agent for enhancing fluidity of a coalwater slurry from a polyether deriv., a maleic acid deriv. monomer, and polyalkyleneimine. CONSTITUTION:A mixture prepared in advance in a proportion of 20-95wt% polyether deriv. having 5,000-10,000molwt., 3-50wt% copolymer derived from polyalkylene glycol monoallyl ether and maleic acid type monomer, and 2- 30wt% polyalkyleneimine is added at the time of preparing the slurry, or a couple of the polyether deriv. and said copolymer, and said polyalkyleneimine are separately added at the time of preparing the slurry.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dispersant for coal-water slurries. More specifically, the present invention relates to a dispersant that provides a fluidized coal-water slurry even when coal powder is dispersed in water at a high concentration.

Petroleum, which has traditionally been widely used as an energy source,
Its price has increased significantly and there are concerns that it will run out.

Therefore, the challenge is to develop other energy sources that can provide a stable supply, and coal is once again becoming widely available. However, the biggest problem with the use of coal is transportation problems due to the fact that coal is solid.

Conventionally, mined coal is pulverized into powder, which is made into a coal-water slurry, fluidized, and transported by pipeline.

On the other hand, COM (Coal-
(Oif-Mixture) has entered into demonstration experiments, but since it uses oil, there are problems with stable supply and price, and high-concentration Ishikawa-water slurry is promising as a coal utilization technology in the future. being watched.

This technology of slurrying coal into water is about to be used in an extremely wide range of coal uses, such as direct coal combustion and gasification, as well as high-speed pipeline transportation of coal.
This has become an important issue in the use of Ishikawa. This coal-
It is preferable for the water slurry to be a high-concentration slurry with little water content from the economic and pollution prevention viewpoints. In particular, in the case of direct combustion of coal water slurry, which can eliminate wastewater treatment and pollution problems, the coal water slurry is sent to a cyclone or turbulent burner without dehydration, drying, etc. Since it is fed into the furnace and combusted directly in the furnace, it is necessary to reduce the moisture content as much as possible. There is no need to mention the reason here, but Japanese Patent Publication No. 57-21488
Details are given in the specification.

However, when attempts are made to increase the concentration of coal powder using known techniques, the slurry becomes significantly thickened and loses fluidity. Conversely, if the concentration of coal powder in water is reduced, transportation efficiency, combustion efficiency, etc. will decrease, and if the water slurry of coal is dehydrated and used, the dehydration and drying processes will also be expensive. There are other problems, such as pollution problems.

Conventionally, various dispersants for coal-water slurries have been proposed to solve such problems. For example, sodium oleate, dodecyl benzene sodium sulfonate, alkyl allyl sulfone, polyoxyethylene,
Alkyl phenyl ether, stearylamine human O
These include surfactants such as chloride, and water-soluble polymers such as polyethylene glycol, polyacrylamide, celluloses, and sodium polyacrylate. However, both have insufficient fluidity and lack practicality.

The present inventors have carried out intensive research to solve the above-mentioned problems in dispersants for coal-water slurries. The present invention was completed by discovering that a composition containing [I] has excellent effects as a dispersant for coal-water slurry.

The present invention provides a dispersant for easily producing a coal-water slurry that has fluidity even at high concentrations.

That is, the dispersant for coal-water slurry of the present invention has the following formula: residue of the derivative, R□ is an alkylene oxide residue having 3 to 4 carbon atoms, and i is the average number of moles added, 0 to 100.
, m is the average number of added moles of ethylene oxide, 50 to 1o
oo, n is the number of functional groups) [15000
~100,000 polyether derivatives (T) (B) Polyalkylene glycol monoallyl ether (
a) and a copolymer derived from maleic acid monomer (U) and (C) one or more compounds selected from the group consisting of polyalkyleneimine and polyal-4-nyleneimine derivatives. (III) This invention relates to a dispersant for coal-water slurry characterized by containing the following.

? :il,! - The coal used in the water slurry may be, for example,
Any type of coal, such as anthracite, bituminous coal, sub-bituminous coal, lignite, etc., can be used regardless of its type and origin, as well as its moisture content and chemical composition. Such coal is wet- or dry-pulverized by a conventional method to obtain a 200 mesh bath of 501 it% or more, preferably 7
The standard usage range is 0 to 80% by weight. Further, the slurry concentration is 60 to 90% on a dry basis of pulverized coal, and if it is less than 60%, it has no practical meaning in terms of economical efficiency, transportation efficiency, combustion efficiency, etc.

Polyether derivative (I), corectangular polymer (I) and compound (I[
[) can be produced by the following method.

The polyether derivative (T) with molecules of 15,000 to 100,000 of the present invention has the general formula A C(RI O)z (CH2CH
20) mH] n, where A is a residue of a reaction starting material having various functional groups having one or more active hydrogen in the molecule, and various C3-4 carbon atoms. After an alkylene oxide, such as propylene oxide or butylene oxide, is subjected to addition reaction I in a conventional manner under pressure using a catalyst such as an alkali or acid, ethylene oxide is added in a similar manner.

R1 is an alkylene oxide residue having 3 to 4 carbon atoms.

t is 0 to 100 and represents the average number of added moles of alkylene oxide, and 2 is 50 to 1000 and is the average number of added moles of ethylene oxide. n is a number that is the same as or smaller than the functional number of the reaction starting material, and alkylene oxide may be bonded to all the functional numbers or only to a part of the functional numbers.

One type or two or more types of RIO may be used (the arrangement thereof may be either block type and/or random type).

Further, a polyether derivative in which the sum of the carbon number of R1 (,5xn) times the carbon number of A is 10 to 800 can be used successfully.

The active hydrogen groups referred to herein include alcoholase 1 hydroxyl groups, phenolic hydroxyl groups, amine groups, carboxylic acid groups, and the like, and are starting materials containing one or more of these groups. Specific examples of these are as follows.

Examples of alcohols containing active hydrogen groups of 1iI or more include ethyl alcohol, butyl alcohol, octyl alcohol, stearyl alcohol, ceryl alcohol, C12
-14 secondary alcohol, (trade name Softanol ■ manufactured by Nippon Shokubai Chemical), ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, butylene glycol, polybutylene glycol,
Useful examples include butanediol, bentanediol, glycerin, butanetriol, hexanetriol, trimethylolpropane, triethanolamine, diglycerin, pentaerythritol, sorbitan, sorbitol, glucose, Sicorose, partially saponified polyvinyl acetate, cellulose, starch, etc. It is.

In addition, examples of amines containing one or more active hydrogen groups include dimethylamine, methylamine, ethylamine, butylamine, butylamine, allylamine, amylamine, octylamine, dodecylamine, laurylamine, tetradecylamine, octadecylamine, and tallow alkylamine. , coconut alkylamines, aniline, toluidine,
Nitroamine, benzylamine, chloraniline, cyclohexylamine, ammonia, tallow propylene diamine, ethylene diamine, tetramethylene diamine, phenylene diamine, benzidine, cyclohexyl diamine, diethylene triamine, triethylene tetramine, tetraethylene bentamine, and the like are useful.

Examples of carboxylic acids containing one or more active hydrogen groups include acetic acid, lauric acid, oleic acid, stearic acid, oxalic acid,
Malonic acid, phthalic acid, fumaric acid, maleic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, dimer acid, phenylene diacetic acid, hemimelitic acid, 1~limellitic acid, 1~rimesic acid, bimerihelic acid, Counting conductors such as ethylenediaminetetraacetic acid can also be used.

Furthermore, examples of phenols containing one or more active hydrogen groups include phenol, bisphenol, cresol, alkylphenol, hydroquinone, and other compounds having an aromatic water group are useful.

Furthermore, compounds containing different types of active hydrogen groups in the same molecule, such as lactic acid, malic acid, glycolic acid, monoethanolamine, jetanolamine, and amino acids, can also be used.

As the copolymer (11) of the present invention, a copolymer (It) derived from polyalkylene glycol monoallyl ether (I) and a maleic acid monomer (I) can be used, preferably with the general formula % Formula % (However, in the formula, X and y are 0, Nu is a positive integer, X, l = 1 ~
100, and the moC2H40+ unit and (-C3
The H a O+ subunits may be bonded in any order. ) Polyalkylene glycol monoallyl ether (a) represented by the general formula % formula % (wherein R2 and R3 each represent hydrogen or a methyl group, and X and Y each represent (- C 2 H 4
Q → C3H60 child qRa (R4 represents hydrogen or an alkyl group having 1 to 20 carbon atoms, p and q
is 0 or a positive integer 1) +Q = θ ~ 100,
moC2H40te unit and (-c3I(ao-) unit may be bonded in any order), -valent metal,
Represents a divalent metal, an ammonium group, or an organic amine group.

) is a copolymer (IF) derived from the maleic acid monomer (0).

Polyalkylene glycol monoallyl ether (a) can be synthesized by a known method of directly adding ethylene oxide and/or propylene oxide to allyl alcohol using an alkali such as Koll or NaOl-1 as a catalyst. As long as it is represented by the above general formula, it is possible to use either a single structure or a mixture.

Maleic acid (monochronic compound) is represented by the general formula ↑ above, and specifically includes maleic acid, fumaric acid, citraconic acid, mesaconic acid, and monovalent metal salts and divalent metal salts of these acids. salt, ammonium salt.

Organic amine salts and these acids and HO (-C 2 H4
0-).

Mo C s H a O ) q R' (However, R4
represents hydrogen or an alkyl group having 1 to 20 carbon atoms, p
and q is 0 or a positive integer, and esters with alcohols represented by p+ (1 = o to 100, +C3H60+ units and moC2H40+ units may be bonded in any order) are listed. For example, secondary alcohol ethoxylate monomale-1 can be suitably used. One or more of these can be used.

Copolymer (11) was derived using polyalkylene glycol monoallyl ether (a) and maleic acid monomer (a) in proportions of 20 to 80 mol% and 80 to 20 mol%, respectively. It is something. By keeping the ratio within this range, a dispersant for coal-water slurry with excellent performance can be obtained.

In order to produce a copolymer (IT) by copolymerization, the single chain component may be copolymerized using an interpolymerization TLH agent. Copolymerization can be carried out by methods such as polymerization in a solvent or bulk polymerization.

The subassembly in a solvent can be carried out either batchwise or continuously, and the solvents used at that time include water, lower alcohols such as methyl alcohol, ethyl alcohol, and isopropyl alcohol, benzene, 1-toluene, xylene, Aromatic or aliphatic hydrocarbons such as cyclohexane and n-hexane; ethyl acetate; ketone compounds such as methyl and methylketone; and the like. The solubility of the raw material 111 and the obtained copolymer <TI) and the copolymer (
From the convenience of using lF・), water and M prime number 1~
4. Lower alcohol J: It is preferable to use at least one selected from the group consisting of: Among the lower alcohols having 1 to 4 carbon atoms, methyl alcohol, ethyl alcohol, and isopropyl alcohol are particularly preferred.

When polymerization is carried out in an aqueous medium, a water-soluble polymerization initiator such as ammonium or alkali metal persulfate M salt or hydrogen peroxide is used as the polymerization initiator. At this time, an accelerator such as sodium bisulfite can also be used.

In addition, for polymerization using lower alcohols, aromatic hydrocarbons, aliphatic hydrocarbons, ethyl acetate, or ketone compounds as solvents, peroxides such as benzoyl peroxide and lauroyl peroxide; hydroperoxides such as cumene hydroperoxide, etc. Oxide; aliphatic azo compounds such as azobisisobutyronitrile are used as polymerization initiators. At this time, use an accelerator such as an amine compound.
can. Furthermore, when a water-lower alcohol mixed solvent is used, it can be appropriately selected from among the above-mentioned various polymerization amounts 9 (agents or combinations of polymerization initiators and accelerators). It is determined appropriately depending on the solvent and polymerization initiator used, but it is usually carried out within the range of '0 to 120'C.

Bulk polymerization is carried out using peroxides such as benzoyl peroxide and lauroyl peroxide; hyde such as cumene hydroperoxide; aliphatic azo compounds such as azobisin butyuni-1-lyl; It is carried out within a temperature range of 150'C.

The copolymer (IF) thus obtained may be used after being further neutralized with an alkaline substance, if necessary.

Preferred examples of such alkaline substances include hydroxides, chlorides, and carbonates of -valent metals and divalent metals, ammonia, organic amines, and the like.

Further, the molecular weight of the copolymer (I) can be in a wide range, but it is preferably in the range of 5oo to so, ooo.

Compounds constituting the dispersant for coal-water slurry of the present invention (
The polyalkylene imine and polyalkylene imine derivative of III) can be produced by the method shown below.

The polyalkyleneimine of the present invention is a homopolymer or copolymer consisting of at least one alkyleneimine monomer. The alkyleneimine monomers are 1,2-alkyleneimine (aziridine) and 1,3-alkyleneimine (azetidine), and specific examples thereof include ethyleneimine, 1°2-propyleneimine, and 1,3-propylene. Imine, 1-methylaziridine, 2.2-dimethylaziridine, 1-ethylaziridine, 2-ethylaziridine, 2-n-propylaziridine, 2-isopropylaziridine, 2-n-butylaziridine, 2-isobutylaziridine, 1- (2-aminoethyl)aziridine,
Examples include 1-(2-cyanoethyl)aziridine and 1-(2-hydroxyethyl)aziridine.

Homopolymerization and copolymerization of alkyleneimine monomers to polyalkyleneimines are promoted with acid catalysts and are easily carried out by methods known per se.

The form of copolymerization of the alkyleneimine monomer may be random copolymerization, block copolymerization, graft copolymerization, or the like.

Typical polyalkylene imines used in the present invention are polyalkylene imines and polypropylene imines, which are produced on an industrial scale and are readily available commercially.

Another preferred polyalkyleneimine is poly(ethyleneimine-propyleneimine) copolymer. The molecular weight of the polyalkyleneimine is not particularly limited, and a wide range of 600 to 1,000,000 is usually used, but a range of 5,000 to 200,000 is particularly preferred.

Polyalkyleneimine derivatives are so-called modified polyalkyleneimine derivatives that are made by reacting some of the amino groups of polyalkyleneimine with a compound that has a functional group that is reactive with amino groups to make them soluble in water or a solvent mainly composed of water. means polyalkyleneimine.

A specific example of such a polyalkyleneimine derivative is τ
is a polyalkyleneimine derivative obtained by reacting a compound having an active double bond such as acrylamide or acrylonitrile; a polyalkyleneimine derivative obtained by reacting an aldehyde such as formaldehyde or acetaldehyde; Examples include polyalkyleneimine derivatives obtained by reacting acid anhydrides such as, but of course, the present invention is not limited to these.

One type of polyalkylene imine derivative may be used alone, or two or more types may be used in combination.

It can also be used in combination with polyalkyleneimine.

The dispersant for coal-water slurry of the present invention contains a polyether derivative (■), a copolymer (If), and a compound (III) as active ingredients, and the ratio of these used is not particularly limited. Polyether derivative (■) /
Copolymer (■)/Compound (Iff): 20-95% by weight
/ A ratio of 3 to 50% by weight - 30% by weight exhibits particularly excellent performance.

The dispersant for coal-water slurries of the present invention is used in pulverized coal-water slurries, but the amount added is not particularly limited and is effective over a wide range of amounts. It is used in a proportion of 0.05 to 3% by weight (dry basis), preferably 0.1 to 2% by weight.

To use the dispersant for coal-water slurry of the present invention, the polyether derivative (■), copolymer (IT), and compound (IIl[) are mixed in advance and then added at the time of slurry preparation. or polyether derivatives (
1), copolymer (If), and compound (III) may be added separately at the time of slurry preparation.

Alternatively, it may be mixed with coal in advance and then made into a slurry (or it may be dissolved in water in advance.Also, due to the nature of the dispersant, it is difficult to slurry coal in water. Anything you can afford is fine.

The scope of the present invention is not intended to be limited by these addition methods and sulfurization methods.

Next, the dispersant for coal-water slurry of the present invention will be explained in more detail with reference to comparative examples and examples, but the present invention is of course not limited thereto.

In the examples, unless otherwise specified, % means % by weight, and parts represent parts by weight.

Preparation of copolymer ll-1 Polyalkylene glycol monoallyl ether (average of 5 ethylene oxide units per molecule) was placed in a glass reaction vessel equipped with a stirrer, a dropping tube, a gas inlet tube, and a reflux condenser at a temperature of 81. ) and 100 parts of water were charged, the inside of the reaction vessel was purged with nitrogen while stirring, and heated to 95° C. in a nitrogen atmosphere.

Then, 1 part of an aqueous solution of 9117.7 parts of maleic anhydride and 14.2 parts of ammonium persulfate dissolved in 246.6 parts of water was added.
Added in 20 minutes. After the addition is complete, add another 14.2 parts of 20
% aqueous ammonium peroxide solution was added over 20 minutes.

After the addition was completed, the temperature inside the reaction vessel was maintained at 95° C. for 100 minutes to complete the polymerization reaction, and an aqueous copolymer solution was obtained. Next, a 40% aqueous solution of caustic soda was added to neutralize the mixture to obtain an aqueous solution of copolymer IT-1.

The P l-1 and viscosity of this aqueous solution of copolymer 11-1 were as shown in Table-1.

Preparation of Copolymer 11-2 Polyalkylene glycol monoallyl ether (average of 5 ethylene oxides per molecule) was placed in a glass reaction vessel equipped with a thermometer, stirrer, dropping tube, gas inlet tube, and reflux condenser. (including units) 222.7 Part 2
alcohol 3 mole ethoxylate (softanol-3
0, manufactured by Nippon Shokubai Kagaku Kogyo ■) Monomaleate 344.2 parts 1. 250 in a mixed solution consisting of 250.2 parts of isopropyl alcohol and 17.0 parts of benzoyl peroxide.
．． Two parts were charged, and the inside of the reaction vessel was replaced with nitrogen while stirring, and heated to the boiling point of the mixed solution in a nitrogen atmosphere. Thereafter, 583.9 parts of the remaining mixed solution was added over 120 minutes. After the addition was completed, the temperature in the reaction vessel was maintained at the boiling point for 120 minutes to continue the polymerization reaction. Thereafter, the temperature inside the reaction vessel was returned to room temperature, 11.0 parts of benzoyl peroxide was added and heated again, and the isopropyl alcohol was distilled off to obtain a copolymer. Next, 40% caustic soda aqueous solution and deionized water were added to neutralize the mixture to obtain an aqueous solution of copolymer Tl-2. The pH and viscosity of this aqueous solution of copolymer U-2 were as shown in Table-1.

Table-1 Aqueous solution 31.7 containing predetermined amounts of various dispersants shown in Example Table-2
Preasol charcoal 68.3 (moisture content 5,
1%) in portions at room temperature with stirring. After adding the entire amount, mix with a homo mixer (manufactured by Tokushu Kika T) for 10.
A coal-water slurry was prepared by stirring with OOORPM for 12 minutes, and the viscosity was measured at 25°C to evaluate the fluidity.

The results are not shown in Table-2. Low viscosity indicates good fluidity.

The substances of compound (I[l) shown in Table 2 are as follows.

■-1; Polyethyleneimine (molecular weight approximately 100,000) ■-2
:Polybutyleneimine (molecular weight approximately 50,000) ■-3; Ethyleneimine 30 mol/1.2-propylene imine 1.0 mol conjugate (molecular weight approximately 30,000) I[1-4; Acrylonitrile addition (0,1 mole) polyethyleneimine (molecular weight approximately 70,000)

Claims (4)

[Claims] (1) (A > general formula % formula %)) (wherein A is the residue of alcohols, phenols, amines, carboxylic acids and derivatives thereof having one or more active hydrogen in the molecule, R1 is an alkylene oxide residue having 3 to 4 carbon atoms, and l is the average number of moles added, 0 to 100.
, l is the average number of added moles of ethylene oxide, 50 to 10
00, n is the number of functional groups) A polyether derivative (D) with a molecular weight of 5000 to 100,000, (F A stone disease characterized by containing the derived copolymer (H) and (C) one or more compounds (III) selected from the group consisting of polyalkylene imine and polyalkylene imine derivatives. - Dispersant for water slurry. (2) In the polyether derivative (I), the total number of carbon atoms (tXn > times the number of carbon atoms in R1 is 10 to 800
The dispersant according to claim 1. (3) Claims 1 to 3, wherein the polyalkyleneimine is polyethyleneimine or polypropyleneimine.
The dispersant according to any one of Item 2. (4) The dispersant according to claim 1, wherein the polyalkylene imine or polyalkylene imine derivative has an average molecular weight of 5,000 to 200,000.