JPH01318085A - Additive for pulverized coal/oil mixture - Google Patents

Abstract

PURPOSE:To obtain an additive which can improve the stability of a pulverized coal/oil mixture and can prevent coal ash from depositing on an apparatus by mixing a specified polyether compound with a polyamine. CONSTITUTION:A reaction product of a polyamine (a) of 2-6 N atoms (e.g., ethylenediamine) with at least one member (b) selected from among an aldehyde and a ketone (i), an alkyl halide (ii), a (thio)isocyanate (iii), an active double bond-containing compound (iv) and an epoxy compound (v) (e.g., iododecane) and an alkylene oxide (c) (e.g., ethylene oxide) are subjected to an addition reaction to obtain a polyether compound (A) of an MW of 1000-200000, containing 3-80wt %, desirably, 5-50wt.% ethylene oxide as component (c). Component A is mixed with a polyamine (B) of the formula (wherein R<1> and R<3> are each a 1-30C alkyl or acyl or H; R<2> is a 2-6C alkylene; and n=1-20), e.g., beef tallow fatty acid, in a mixing ratio of A to B of (95-5)/(5-95) to obtain the title additive. 0.01-5wt.% said additive is added to a mixture of pulverized coal, an oil and, optionally, water, and the mixture is mixed at 50-120 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a pulverized coal-oil mixture (hereinafter referred to as COM) for improving stability and preventing coal ash from adhering to various equipment.
It is related to additives for use.

In the past, coal particle sedimentation caused problems with Jianmai Hikitechun COM, but this problem was solved with the invention of an excellent stabilizer, and it has already been produced in large quantities as an oil-alternative fuel for electric power, and is being used for combustion. has been done. However, the ash contained in C0M adheres to places where strong mixing and agitation occurs, such as the stirrer, C0M pump, control valve, and elbow of piping, or where the flow rate changes suddenly.
It has become necessary to frequently stop the line for scraping, cleaning, etc., and new problems have arisen. In addition, 7-do-ether compounds such as imines shown in JP-A No. 57-165490 have a large number of side chains in one molecule and have a complex or shingle-like structure, so additives and In order to achieve this effect, it was necessary to provide sufficient energy for mixing, and ash adhesion also occurred. Therefore, there has been a strong desire to develop additives that further improve the stability of COM and prevent ash adhesion.

As a result of intensive research into additives that maintain long-term stability and prevent ash adhesion, the inventors of the present invention used a polyamine derivative having a specific number of nitrogen atoms as a starting material, and added alkylene oxide to this additive. It has been found that an additive containing a polyether compound having a specific molecular weight and a polyamine or a derivative thereof is very effective.

By using the additive of the present invention, not only under strong stirring but also
It is possible to produce stable COM even under low agitation, which was not possible before, and COM without ash adhesion can be obtained.
COM can be stored in tanks for a long period of time, and there is no ash adhesion to various equipment such as COM pumps and control valves, making mass production and combustion possible.

Coal used for COM includes, for example, anthracite coal, bituminous coal,
Various types of coal such as sub-bituminous coal and lignite can be used, and any type of coal can be used regardless of its type, production area, chemical composition, or moisture content. Such coal may be directly pulverized coal as it is or after being coarsely crushed and placed in oil to be pulverized coal directly in oil using various wet pulverizers, or pulverized coal may be pulverized using a conventional dry pulverizer. However, the wet grinding method
It is even better because the stability of COM is improved and spontaneous combustion and dust can be prevented during crushing. Moisture in the coal may be removed during dry pulverization, or may be crushed during or after wet pulverization, and there is no problem even if coal containing low moisture is not removed. Judging from combustibility, the particle size of pulverized coal is usually preferably 200 microns or less in average particle size, and even smaller particle size 100 microns or less, but as far as physical properties such as COM stability are concerned, the particle size may be even smaller. There is no problem even if it is large. The content of this fine powder is 20 to 70% by weight based on the final mixture, and if it contains more than 70% of pulverized coal, the viscosity will become extremely high and fluidity will be lost, which is undesirable. In this case, the economic advantages associated with the inclusion of pulverized coal are reduced, which is not preferable. Therefore, 2
It can be contained in an amount of 0 to 70% by weight, more preferably 30 to 60% by weight.

In addition, the oil used for COM refers to coal crude oil, various fractions obtained from crude oil, such as kerosene, light oil, A heavy oil, B heavy oil, C
Oils and waste oils commonly used as fuel such as heavy oil, ethylene decomposition residual oil, creosote oil, anthracene oil, and various blended oils, such as gas station waste oil (automobile lubricating oil, cleaning oil), ironworks waste oil (machine oil, cutting oil, cleaning oil and mixed oil), waste oil from oil tankers and other ships, -
Refers to general chemical factory waste oil, etc., and also includes mutual mixtures thereof. Among them, it is preferable to use petroleum crude oil, B heavy oil, and C heavy oil. The COM may be prepared by using only a single oil or a pre-blended oil, or by mixing or co-firing a COM made with a single oil (preferably petroleum crude oil or heavy oil).

Water is caused by moisture contained in coal mixed into C0M,
There are cases where manufacturers or users add water, but transportation costs, storage costs, and other general and administrative costs will increase by the volume of water.
Furthermore, it steals the heat of vaporization during combustion and increases heat loss, which is undesirable, and the less the better. On the other hand, since water has the property of improving the stability of COM and the effect of reducing NOx and vizine in exhaust gas during combustion, a small amount of water is allowed. Therefore, the total water content is preferably 15% by weight or less, preferably 6% by weight or less, and may not be contained at all.

The additive for pulverized coal-oil mixtures according to the present invention uses (A) a polyamine derivative having 2 to 6 nitrogen atoms as a starting material, adds an alkylene oxide to this, and reduces the molecular weight to 100 ~200,000 polyether compound, and further (B)-removal % formula % (R1, R3: alkyl group or acyl group or hydrogen atom having 1 to 30 carbon atoms, R2: alkylene group having 2 to 6 carbon atoms, n=1 to 20) Contains a polyamine shown as an essential component.

Further, it is preferable that the polyether compound contains ethylene oxide as an alkylene oxide, and the content thereof is 3 to 80% by weight, preferably 5 to 50% by weight, based on the polyether compound.

The polyamine derivatives referred to here are those having 2 to 2 nitrogen atoms.
Six polyamines, such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, or mixtures thereof, are reacted with the compounds shown below.

(aldehydes, ketones An example of aldehydes is formaldehyde.

Aliphatic aldehydes such as acetaldehyde, butyraldehyde, isobutyraldehyde, capryaldehyde, lauric aldehyde, stearaldehyde, aliphatic dialdehydes such as glyoxal and succindialdehyde, and benzaldehyde.

Examples include aromatic aldehydes such as salicylaldehyde and α-naphthaldehyde.

Examples of ketones include aliphatic ketones such as acetone, ethyl methyl ketone, methyl vinyl ketone, methyl isobutyl ketone, and diisopropyl ketone, alicyclic ketones such as cyclopentanone and cyclohexanone, acetophenone, propiophenone, and benzophenone. , 2-acetonaphthone, and other aromatic ketones.

(b) Alkyl halide Alkyl halide is general 2Cn) 12n+/X [C:
carbon H: hydrogen X: halogen n is an integer of 1 to 30], and the alkyl group thereof is ethyl.

Propyl, isobutyl, tert-butyl, octyl.

Examples include nonyl and decyl groups, and halogens that can be combined with them include fluorine, chlorine, bromine, and iodine.
The combination is not particularly limited.

(c) Isocyanates Examples of isocyanates include monoisocyanates such as methyl isocyanate, ethyl isocyanate, butyl isocyanate, carbanyl, and naphthyl isocyanate, hexamethylene diisocyanate, tolylene diisocyanate, isophorone diisocyanate, metaxylene diisocyanate, and 1,5-naphthylene diisocyanate. , 4.4' diphenylmethane diisocyanate and other polyvalent isocyanates.

(dl Things with active double bonds Examples of things with active double bonds include ethylene, propylene, butene, butadiene, diisobutylene, styrene, α-methylstyrene, vinyltoluene, vinylnaphthalene, etc., acrylic acid, methacrylic acid, acids, carboxylic acids such as crotonic acid, fumaric acid, maleic acid, and itaconic acid, or their esters, acrylamide, and methacrylamide.

Examples include N,N-dimethylacrylamide.

fe) Epoxy Compound Examples of the epoxy compound include glycidyl compounds such as glycidol, allyl glycidyl ether, butyl glycidyl ether, phenyl glycidyl ether, butylphenyl glycidyl ether, and nonylphenyl glycidyl ether.

In short, the starting material is one obtained by reacting any of the compounds shown in fa) to (el) with a polyamine having 2 to 6 nitrogen atoms.

The alkylene oxide added thereto includes ethylene oxide, propylene oxide, butylene oxide, styrene oxide, and the like.

In the case of copolymerization, it may be block copolymerization, random copolymerization, or one in which either of the two is added first, but block copolymerization is more preferable in order to effectively exhibit the surface active ability.

When the alkylene oxide is added, the molecular weight of the resulting polyether compound is 1,000 to 200,000, preferably 2,000.
The ratio is ~100,000. Further, the polyether compound contains ethylene oxide as an alkylene oxide, and the content thereof is 3 to 80% by weight of the polyether compound,
Preferably it is 5 to 50% by weight, which provides even better performance.

Next, the polyamine represented by the general formula in item (B) is a polyamic acid or a derivative thereof such as ethylenediamine, beef tallow propylene diamine, triethylenetetramine, tetraethylenepentamine, and pentaethylenehexane. Derivatives are reaction products with alkyl halides, such as dodecylpropylene diamine, dodecyltriethylenetetramine, tallow dipropylenetriamine, and the like.

Also polyamines and fatty acids, such as octyl acid.

Stearic acid, oleic acid, especially coconut oil fatty acids.

Amidated products with beef tallow fatty acids are effective.

The blending ratio of polyether (A) and polyamine (B) of the present invention is A/B=9515 to 5/95, preferably 90/
10-50150.

In order to stabilize COM and exhibit the ash adhesion prevention effect using the additive of the present invention, the additive must be added after dry-pulverized pulverized coal is mixed into oil, or the additive must be dissolved in oil in advance and then dry-pulverized. Either pulverized pulverized coal may be added, or pulverized coal, oil and additives may be mixed all at once, and water may be added to each of them. In the case of wet pulverization, it may be added before pulverization, during pulverization, or after pulverization. In this case as well, water may be added.

The amount of the additive of the present invention added to the mixed fuel system varies slightly depending on the coal type, coal particle size distribution, and oil type, but is generally 0.01 to 5% by weight, preferably 0.04 to 0.0% by weight in the mixed fuel.
．． 8% by weight and the overlay is for economic reasons only.

According to the present invention, when forming a dispersion system consisting of additives, pulverized coal, oil, and optionally water, any temperature can be adopted, for example, mixing at 50 to 120°C, and the mixing pressure can be elevated pressure, normal pressure, or reduced pressure. It may be performed during degassing, and the stirrer and stirring conditions are not restricted.

Next, the present invention will be explained in more detail with reference to Examples.
The examples are merely for illustrative purposes and are not intended to constrain the spirit of the invention.

Example I As a small-scale model of the stirring section of a C0M manufacturing apparatus, a Homo mixer equipped with a stirring spring for high viscosity produced by Tokushu Kika Kogyo was used, and an ash adhesion prevention test was conducted as follows.

The additive of the present invention was added to COM heated to 90°C, premixed with a spatula, and then heated to 500°C at the same temperature.
Stir for 10 minutes at rpm. Subsequently, after cleaning the COM adhering to the stirrer with a solvent, the amount of ash firmly adhering around the rotating part was measured. It can be said that the lower the ash content, the better the ability to prevent the adhesion of natural ingredients.

Moreover, the C0M stability test was conducted as follows. The test device used is a stainless steel cylinder with an inner diameter of 5.5 ccm and a height of 20 cm, which has an outlet with a stopper at the bottom, 6 cm, and 12 cm from the bottom. Fill this cylinder with the specified mixed fuel to a height of 18C11 from the bottom, remove the stopcock at 12CI11 from the bottom, and then remove the stopcock at 12CI11 from the bottom.
COM) in the cylinder at a location of cm was taken out and used as an upper layer sample, and its viscosity and coal concentration were measured. Next, the stopcock at a position 5 cm from the bottom was removed, and the mixed fuel above that point was sampled and its viscosity and coal concentration were measured as a middle layer sample. Finally, remove the bottom stopper and remove the remaining COM.
The viscosity and coal concentration of the lower layer samples were measured. The viscosity measurements were all conducted at 70''C.

Table 1 shows the additives used in this example. Also, the second
The table shows the ash adhesion prevention rate and stability evaluation results. From Table 2, in the comparative example, pentaethylene hexamine (number of nitrogen atoms: 6) shown as additive (I), C0M
The stability was not sufficient, and there was no effect of preventing ash adhesion.

On the other hand, when the additives (A-F) of the present invention are used, sufficient CO
M stability was obtained, and the ash adhesion prevention rate was 80 to 99%. In particular, the combined use of amidated coconut oil fatty acid and beef tallow fatty acid showed excellent stability and ash adhesion prevention effect.

Example 2 COM of actual machine! li! The ash adhesion prevention test using J construction equipment (1 t/h) was conducted as follows. When producing COM using Australian bituminous coal and Middle East C heavy oil, the additive (E) shown in Table 1 is used as a reaction product of butaethylene octamine (8) and t-butylphenyl glycidyl ether, PO/EO adduct and palm. Fatty acids and pentaethylene hexamine (1:
The amidated product of 1) was used in combination at a blending ratio of 60/40, added to the COM before the line mixer, and operated for 30 days.

As a result, it was confirmed that no natural adhesion occurred on the stirrer, C0M pump, control valve, elbow of piping, etc., and that a stable COM with excellent ash adhesion prevention effect was obtained.

Claims (2)

[Claims] (1) Polyamine having 2 to 6 nitrogen atoms used to improve the stability of pulverized coal-oil mixtures, disperse ash separated from pulverized coal, and prevent ash from adhering to various equipment and (a) aldehydes, ketones, (b) alkyl halides, (c) isocyanates, thioisocyanates, (d) active double bond-containing substances, or (e) epoxy compounds as a starting material. A polyether compound with an alkylene oxide added thereto to have a molecular weight of 1000 to 200,000, and (B) a polyether compound with the general formula R_1-NH-(R_2NH)n-R_3 (R_1, R_3: an alkyl group having 1 to 30 carbon atoms or An additive for pulverized coal-oil mixtures, characterized in that it contains as an essential component a polyamine represented by an acyl group or a hydrogen atom, R_2: an alkylene group having 2 to 6 carbon atoms, n=1 to 20. (2) The polyether compound contains ethylene oxide as an alkylene oxide, and the content thereof is 3 to 80% by weight, preferably 5 to 50% by weight, based on the polyether compound, and the polyamine is The additive for pulverized coal-oil mixtures according to claim 1, which is an amidated product of oil fatty acid or tallow fatty acid.