JPS58215490A - Dispersant for coal/water slurry - Google Patents

Abstract

PURPOSE:To provide the titled dispersant consisting mainly of polyalkyleneimine (derivative) and producing an aqueous slurry of coal which has good fluidity even at a high concentration. CONSTITUTION:Alkyleneimine monomer such as ethyleneimine, 1,2-propyleneimine, 1-methylaziridine or 1- (2-hydroxyethyl)aziridine is (co)polymerized the presence of an acidic catalyst to produce a polyalkyleneimine. When necessary, a polyalkyleneimine derivative is prepared by reacting a reactive functional group-containing compd. (e.g. acrylamide, ethylene oxide, formaldehyde or succinic anhydride) with a part of amino groups of the polyalkyleneimine. The polyalkyleneimine (derivative) is added to coal/water slurry in an amount of about 0.05-3% based on the weight of slack coal to form a slurry with high fluidity.

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 disperses coal powder in water and provides a fluidized coal-water slurry even at high concentrations.

-1- Petroleum, which has traditionally been widely used as an energy source, is
Its price has increased significantly and there are concerns that it will run out.

The challenge is to develop other energy sources that can provide a stable supply of electricity, and coal is once again becoming widely available. However, the biggest problem in using 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-
Q11-M ixture) has entered the demonstration experiment, but since it uses oil, there are problems in terms of stable supply and price, and in the future, high acidity coal will be considered as one of the coal utilization technologies. Water slurry is seen as promising.

This slurry technology of coal in water is about to be used in an extremely wide range of coal uses, such as direct combustion gasification in addition to the above-mentioned coal pipeline transportation, and has become an important issue in coal use. There is. This coal-water slurry is preferably a high INI (i) slurry with low water content, which is economically effective in preventing pollution.In particular, it is desirable to eliminate problems such as wastewater treatment and pollution-F. In the case of direct combustion of coal-water slurry, the coal-water slurry is dehydrated, dried, etc. In order to burn directly in the furnace, it is necessary to reduce the amount of I (containing water). It is described in detail in the 14th Mei MINI.

However, if the concentration of 71 charcoal powder in water is increased by a known technique, the slurry will thicken considerably and lose its fluidity.
let's. Conversely, if the concentration of coal powder in water is reduced, the
I) Efficiency and fuel efficiency decrease, and when using coal water slurry, dehydration and drying T) 1) 1. There are problems such as high costs and pollution problems.

Conventionally, this J: Ui [i! ! l! Various dispersants for coal-water slurries have been proposed to solve this problem. For example, A-Rain chu soda, 1 decyl benzene sous 3
− Surfactants such as sodium sulfonate, alkyl allyl sulfonate, polyoxyethylene alkyl phenyl ether, and stearylamine hydrochloride, water-soluble polymers such as polyethylene glycol, polyacrylamide, celluloses, and sodium polyacrylate, etc. There is. However, both have insufficient fluidity and lack practicality.

The present inventors (Yo) have continued intensive research to solve the above-mentioned problems in dispersants for coal-water slurries, and as a result, a polyalkylene imine selected from the group consisting of certain polyalkylene imines and polyalkylene imine derivatives has been found. The present invention was completed based on the discovery that a composition containing one or more compounds has excellent effects as a dispersant for coal-water slurry.

That is, the present invention provides a dispersant for easily producing a fluidized coal-water slurry even at high temperatures.

That is, the dispersant for coal-water slurry of the present invention has one or two selected from the group consisting of polyalkylene imine and polyalkylene-4-imine derivatives.
Coal characterized by containing a compound fj of type 1-
1J regarding a dispersant for water slurry.

The coal used for the coal-water slurry is, for example, anthracite,
Any type of coal, such as bituminous coal, 1111W internal 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 grinding by conventional methods, 1.
200 mesh pass 50 weight% or more, preferably 1 including 1
The standard for use is 170-80% heavy weight. In addition, the slurry m degree is 60 to 90% on a dry base of pulverized coal.
If the content is less than 60% by weight, it is not practical from the viewpoints of dry bamboo, transportation efficiency, combustion efficiency, etc.

The polyalkylene imine J) and polyalkylene imine M constituting the dispersant of the present invention can be produced by the following method 11/i.

The i);')j'lurunimine of the present invention is a homopolymer = 5- or a copolymer consisting of at least one type of al-4-renimine Ill44. The alkylene imine monomer is 1
．． 2-alkyleneimine (aziridine) and 1,3-
It is an alkyleneimine (azetidine), and its specific examples include ■tyrenimine, 1゜2-propyleneimine,
1.3-propyleneimine, 1-methylaziridine, 2
, 2-dimethylaziridine, 1-ethylaziridine, 2
-ethylaziridine, 2-n-propylaziridine, 2
-isopropylaziridine, 2-n-butylaziridine, 2-isobutylaziridine, 1-(2aminoethyl)
Aziridine, 1-(2-cyanoethyl)aziridine, 1
-(2-hydroxyethyl)aziridine and the like.

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 a single alkylene imine may be random copolymerization, block copolymerization, graft copolymerization, or the like.

Typical polyalkylene E used in the present invention 6
- Min is polyethyleneimine and polypropyleneimine, which is IT! j! It is manufactured on a scale of
Commercially available products can be used. Another preferred polyalkyleneimine is a poly(ethyleneimine-7111 and leneimine) copolymer. The molecular weight of the polyalkyleneimine is not particularly limited. Instead of t], 4;L (1) in a wide range from ioo to 1,000,000 is usually used, but t) in a range of 1111 from 5,000 to 200,000 is particularly preferred.

Polyj') Lekyleneimine M1 is made by reacting a part of the jI mino star of polyalkyleneimine with a compound that has a functional group reactive with an amino group, and in addition, It means the so-called modified polyalco 1: renimine which is soluble in the following solvents.

Specific examples of such [poly)l-1-lenimine derivatives are 1) polyalyl obtained by reacting a compound that forms a width bond with tT activity (I) such as citalyl 7F mido or acrylonitrile: 11 Nonimine derivatives: polyalkylene imine derivatives obtained by reacting epoxide-7-compounds such as ethylene A oxide, polypyrene A di-cyto, glycidol, or epic-1-1-ruhy-1-niline;
Examples include polyalkylene imine derivatives obtained by reacting aldehydes such as formaldehyde or acetaldehyde; polyalkylene imine derivatives obtained by avoiding reaction with acid anhydrides such as oxidized anhydride, but are of course limited to these. It's not a thing. One type of polyalkyleneimine 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 slurries of the present invention is used in coal-water slurries, but the amount added is not particularly limited and is effective over a wide range of amounts. 0.05 to 3% by weight (dry base),
It is preferably used in a ratio of 0.1 to 2%.

To use the dispersant for coal-water slurry of the present invention, 2
When using more than one type of dispersant, the dispersants may be mixed in advance and then added at the time of slurry preparation, or the dispersants may be added separately at the time of slurry preparation. It was pre-mixed with coal and then slurried 17b, and also pre-dissolved in water 1! Teil? I T1), 1: I.

Furthermore, any dispersant may be used as long as it is slurried (or slurried coal in water).

The amount of lead in the present invention is not limited by these addition methods and slurry forming methods.

Next, the dispersant for coal-water slurry of the present invention will be explained in detail with reference to comparative examples and examples. , L
<'t.

4↑O, 1z in the example] 4') Unless otherwise noted, % means weight %, and the cylindrical part t and the Φ hanging part are used as blades.

Example Table 1 shows charcoal 1. :lo (moisture content 5,
1%) was added one by one at room temperature while stirring. After all addition was completed, the coal-water slurry was stirred at 10.00 ORP M for 2 minutes using a small fir 1-li (manufactured by Tokushu Kikako Co., Ltd.), and the viscosity was measured at 25°C. , liquidity was evaluated.

Table 1 shows the connecting beams. Low viscosity indicates good fluidity.

The abbreviations in Table 1 are as follows.

PEI: Polyethyleneimine PPI: Polyp[1 Pyreneimine E1:
Ethyleneimine PI: Propyleneimine 8 N: Acrylonitrile O: Ethylene A oxide = 10 =

Claims (1)

[Scope of Claims] 1. A dispersant for coal-water slurry, which contains one or more compounds selected from the group consisting of polyalkylene imine and polyalkylene imine derivatives. 2. The dispersant according to claim 1, wherein the polyalkyleneimine is polyethyleneimine or polypropyleneimine. 3. 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.