JPS5871994A - Dehydrating agent for coal slurry - Google Patents

Abstract

PURPOSE:A dehydrating agent that contains a specific hydrocarbon, thus permitting high-efficient dehydration and deashing of fine-powder coal slurry especially. CONSTITUTION:The objective dehydrating agent contains a compound of the formula (A is compound with at least one active hydrogen; X is 3-10; R is 2- 600; S is 2-700; Z is 1-50) with a molecular weight of 8,000-50,000, preferably 10,000-40,000 and an HLB of 5-15. The agent is added to a coal slurry usually by 0.01-3.0wt%, preferably 0.02-2.0wt%. The group A in the above formula is, e.g., an alcohol, ammonia, an amine, a phenol, a carboxylic acid, an alkanolamine or a mercaptan.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dehydrating agent for coal slurry, particularly pulverized coal slurry.

Oil, which has traditionally been widely used as an energy source, is facing supply restrictions and rising prices due to resource depletion.
Coal has become difficult to maintain a stable supply due to the rise in coal prices and other factors, and in recent years coal has been reconsidered as an alternative energy source to oil. However, since coal is produced as a lumpy solid, it is more complicated and costly to transport and store than oil!・There are disadvantages such as being expensive.

As part of an attempt to remove these drawbacks and utilize coal more effectively, a technology that involves crushing coal, mixing it with water to form a slurry, and transporting this slurry through pipelines is attracting attention. .

In order to transport coal slurry efficiently, it is necessary to prepare coal slurry with as little water content as possible and with high fluidity, and for this purpose, efficient dehydration of coal slurry is an important process. .

In addition to mechanical methods using sieves or centrifugal dehydrators, there are precipitation methods for dewatering coal slurry.As an example of the latter, a coagulation process in which a nonionic surfactant is added to lump coal slurry after transport by ship is used. A method of dehydration has been proposed (Special Publication No. 56-56204, No. 56-5).
No. 6205).

In addition, since coal contains a considerable amount of ash, efficient removal of ash is an important factor for effective coal utilization. There is no mention of.

On the other hand, since pulverized coal slurry can be transported at a higher concentration than lump coal slurry, pulverized coal slurry transport is becoming the mainstream in the development of coal slurry transport technology. Therefore, the development of techniques for efficiently dehydrating and deashing pulverized coal slurry has become an important issue in this field.

In view of these circumstances, the present inventor has conducted intensive research and found that by using a dehydrating agent containing the compounds described below, it is possible to efficiently dehydrate and deash coal slurry, especially pulverized coal slurry (3). We investigated this and completed the present invention.

That is, the present invention relates to the general formula: %Formula%] (wherein A is the residue of a compound containing at least one active hydrogen, X is from 3 to 10, and therefore R is from 2 to 600 , S is a number from 2 to 700, and S represents a number from 1:11 to 50).

The compound residue A containing at least one active hydrogen includes alcohol residue M-ammonia residue, J, +'u-amine residue, amide residue, phenol residue, (, carboxylic acid residue, alkanolamine residue). group, mercaptan residue,
Examples of addition polymer residues of derivatives of and alkylene oxides are exemplified by Hano 1. Ru.

Alcohol/1QJzl To L, then primary alcohol II'
(For example, lower alcohols such as methanol, ethanol, and n-dityl alcohol, higher (4) alcohols such as lauryl alcohol, stearyl alcohol, and oleyl alcohol, and (U) alcohols such as 2-ethylhexyl alcohol,
tl chain-containing alcohol, cyclohexanol,
benzyl alcohol, etc.), secondary alcohols (e.g., isopropyl alcohol, 2-butanol, etc.), tertiary alcohols (e.g., tert-butanol, etc.), polyhydric alcohols (e.g., , ethylene glycol, propylene glycol, trimethylene glycol, butanediol, hexanediol, glycerin, sorbitan, pentaerythritol, sorbitol, sucrose, cellulose, starch, glycogen, partially saponified polyvinyl acetate, polyacrylic acid derivatives, polyglycerin , dipentaerythritol, etc.) and their esters (eg, monoglyceride, sorbitan monoalkylate, etc.).

Examples of amine residues include primary amines (e.g., monomethylamine, monoethylamine, laurylamine, tallow amine, aniline, toluidine, benzylamine, chloraniline, etc.), secondary amines (e.g., EVA, diethylamine, methylstearylamine, N-methyl -anilino, morpholine, etc.), and polyamines (e.g., ethylenediamine, propylene diamine, hexamethylene diamine, phenylene diamine, diethylene triamine, pentaethylene hexamine, etc.).

Examples of the amide residue include lauric acid amide, stearic acid amide, and adipic acid amide residues.

As the phenol residue M, phenol, full 7"-ol,
Alkylphenol, phenylphenol, styrenated phenol, resorcinol, hydroquinone, pyrogallol, naphyl phenol, argyl naphyl phenol, and the remainder of these formalin compounds are exemplified.

Carphonic acid residues include lower and higher monocarboxylic acids such as acetic acid, diuric acid, oleic acid, linoleic acid, ricinoleic acid, and phenylacetic acid; dicarboxylic acids such as oxalic acid, succinic acid, adipic acid, and phthalic acid; dimer acids; Polycarboxylic acids such as trimellidic acid and pyronori-1-acid, acrylic acid,
Examples include polymers containing polymerizable carboxylic acid residues such as methacrylic acid and maleic anhydride, and residues of partially esterified polycarboxylic acids.

Examples of alkanolamine residues include monoethanolamine, jetanolamine, and triethanolamine residues, but monoalkylalkanolamine residues such as monoethylpropanolamine may also be used.

7 Mercaptan residues include lauryl mercaptan,
and each residue of dodecylphenyl mercaptan.

Examples of addition polymer residues of alkylene oxide include polyoxymethylene, polyethylene glycol, polypropylene glycol, poly1-rimethylene glycol, and polyoxyethylene/polyoxypropylene copolymer (random, block) residues. Illustrated.

Other amino acids such as chrysin, glutamic acid, threonic acid, polychrysin, polyglutamine (7), polyamino acids such as glycolic acid, hydroxy acids such as ricinoleic acid, salicylic acid, 1)-aminobenzoic acid, and aminophenol, etc. Each residue of a compound having two active hydrogens is exemplified.

In the general formula f3iI, X is 3 to 10, preferably 3
~5. R is 2-6()0, preferably 5-300, S
If 2~700, preferably tL<1q15~400.2 if 1~5
0, preferably a number from 1 to 20.

The minute-r-meter of the compound represented by the above general formula is usually 800
0~50000. Preferably I (1(100-4(1
000, 8000 or less has sufficient syneresis PI, demineralization is 111 <<, 50 (100 or more) HIW 1
- low 1;, viscosity 1, 1: high 2, making it difficult to handle.

Furthermore, the HL B of the compound represented by the above general formula is 5 to 1.
A value in the range of 5 is preferable; in general, if it is less than 5, it will be difficult to dissolve uniformly, resulting in a decrease in water repellency, and if it is more than 15, the ability to migrate to the water layer will be large, resulting in a decrease in meat aqueous properties and demineralization. .

The compound represented by the general formula I'Iil used in the present invention is:

It can be easily moved by conventional methods, and can be made of two or more types (
8) May be used as a mixture.

In addition to the compound represented by the above general formula, the dehydrating agent for lime slurry according to the present invention may optionally contain various additives, such as:
A cationic surfactant such as ammonium dimethyl tallow, tallow amine, alkylamine low EO adduct, a polyoxyethylene polyoxypropylene block copolymer, etc. may be blended as appropriate.

The dehydrating agent according to the present invention is 0.01 to 30% by weight, preferably 0.02 to 20% by weight, based on the coal slurry, or 0.01 to 30% by weight, preferably 0.02 to 20% by weight, based on the compound represented by the general formula n11, or 0.01 to 30% by weight, preferably 0.02 to 20% by weight, based on the compound represented by the general formula n11. 03-15.0% by weight, preferably 0.03-15.0% by weight.
It is generally added in a proportion of 0.05 to 10.0% by weight.

The concentration of the coal slurry to which the dehydrating agent according to the present invention is added depends on the coal particle size, etc., and is not particularly limited. It is preferable to set the weight to .0%.

When the dehydrating agent according to the present invention is used in combination with conventional flotation agents, such as 4-methyl-2-pentanol and diesel oil, paraffin Freon-1 oil, etc., its dehydrating efficiency and deashing efficiency are greatly increased. be able to. In this case, the dehydrating agent is usually added to the coal slurry at the same time as the flotation agent, but it may be added to the coal slurry after being treated with the flotation agent.

By using the dehydrating agent according to the present invention, the water separation rate of coal slurry is accelerated and the dewatering efficiency is increased, and
Deashing efficiency is also increased.

Although the present invention is mainly aimed at pulverized coal slurry, it is applicable to the dehydrating agent d agglomerated slurry (for example, particle size 0.
It is sufficiently effective even when applied to a coal tree of 0.01 to 0.5 tn.

Hereinafter, the present invention will be explained by examples.

Examples 1 to 14 and Comparative Examples 1 to 4 Pulverized Daido coal (200 mesh l'!: 84% passing through li) was made into a 10% water slurry, and 0.2 g of diesel l was added to it.
%, 4-methyl-2-pentanol 0.05% O': and a predetermined amount of dehydrating agent shown in Table 1 was added to the deashing process 111! 500 y of the same yielded coal was suctioned and dehydrated as flotation froth (Lh 500 m Hg), and the moisture content and ash reduction rate were determined. The results are shown in Table-1.

(11) Table-1 (12)

Claims (1)

[Claims] ■, general formula % formula %20, where A is the residue of a compound containing at least one active hydrogen, X is a number from 3 to 10, R is a number from 2 to 600, S
is a number from 2 to 700, and Z is a number from 1 to 50) A dehydrating agent for coal slurry containing a compound represented by the following. 2. A is a residue selected from the group consisting of alcohols, ammonia, amines, amides, phenols, carboxylic acids, alkanolamines, mercaptans, and each residue of these derivatives and alkylene oxide addition polymers; The dehydrating agent according to item 1, which is a group. 3. Dehydration according to item 1, wherein the molecular weight of the compound is 8,000 to 50,000, preferably 10,000 to 40,000.
2. The dehydrating agent according to item 1, wherein the compound has an HLB of 5 to 15.