JPS598389B2 - Additive for pulverized coal-oil mixture - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an additive for a pulverized coal/oil mixture for producing a pulverized coal/oil mixture with excellent stability and fluidity.

Conventionally, although pulverized coal has a low price per calorific value, it has disadvantages such as difficulty in transportation, difficulty in controlling combustion, low calorific value, and large storage space. However, there was a problem with fuel.

A mixture of pulverized coal and oil does not have the above-mentioned drawbacks and has high practical value because it has a lower price per calorific value than oil alone.

However, simply mixing pulverized coal and oil does not result in a satisfactory pulverized coal-oil mixture because the pulverized coal particles settle and separate due to the difference in specific gravity, coagulate, and lose fluidity.

Therefore, it is important to find additives that improve stability and fluidity, and the present inventors have already succeeded in overcoming the above problems and finding effective additives. This made it possible to put it into practical use.

(Japanese Patent Application Laid-Open No. 53-78207) As a result of our intensive research to obtain a more economical pulverized coal-oil mixture that maintains stability and fluidity for a longer period of time, we found that the pulverized coal and oil mixture described below We succeeded in discovering an additive for charcoal/oil mixtures and succeeded in producing a very superior pulverized coal/oil mixture.

According to the present invention, a pulverized coal-oil mixture with significantly improved stability and fluidity than before can be obtained, and even when stored for a long period of time at not only room temperature but also high temperature, pulverized coal will hardly settle, and even if it does occur slightly. However, due to the excellent action of this agent, there is almost no agglomeration of settled pulverized coal, so it can be re-fluidized with only simple stirring.

Of course, stirring is not necessary for a short period of time (about 15 days).

This has made it possible to safely transport the pulverized coal overnight mixture in tankers over long periods of time, store it in tanks, and transport it through pipelines and piping.

In addition, the amount of this drug to be used is smaller than that of the conventional method, and from an economical point of view, it has further promoted the practical application of pulverized coal and oil mixtures.

The coal used in the pulverized coal-oil mixture includes various types of coal, such as anthracite, bituminous coal, sub-bituminous coal, and lignite, regardless of its type, production area, chemical composition, or moisture content. can.

The coal is either left as it is, or coarsely crushed and placed in oil, and made into pulverized coal directly in oil using various wet crushers;
Alternatively, it may be made into pulverized coal using a conventional dry pulverizer.

However, the wet pulverization method is better because it improves the stability of the pulverized coal-oil mixture and prevents spontaneous combustion and dust during pulverization.

Moisture in the coal may be removed during dry pulverization, or during or after wet pulverization, and if the coal contains a small amount of moisture, there is no problem even if it is not removed.

The particle size of pulverized coal is determined from combustibility, and is usually an average particle size of 2.
00μ or less is preferable, and even smaller particle size is 100μ.
It is preferable that the particle size is less than μ, but as far as the physical properties such as the stability of the overnight mixture of pulverized coal are concerned, there is no problem even if the particle size is larger.

The content of this pulverized coal is 20 to 70% by weight based on the final mixture. If the pulverized coal is contained in an amount of 70% by weight or more, the viscosity will become extremely high and fluidity will be lost, which is undesirable. The following cases are preferred because the economic advantages associated with the inclusion of pulverized coal are reduced.

Therefore, it can contain 20 to 70% by weight, but 30 to 60% by weight.
% by weight is more preferred.

In addition, the oil used in the pulverized coal-oil mixture includes petroleum crude oil, various fractions obtained from crude oil, such as kerosene, light oil, A heavy oil,
Oils and waste oils commonly used as fuel such as B heavy oil, C heavy oil, ethylene decomposition residual oil, creonate oil, anthracene oil, various blended oils, etc., such as gas station waste oil (automobile lubricating oil, cleaning oil) ironwork waste oil (machine oil) , cutting oil, cleaning oil, and mixtures thereof), waste oil from oil tankers and other ships, waste oil from general chemical factories, etc., and also includes mixtures of these oils.

Among them, it is preferable to use petroleum crude oil, B heavy oil, and C heavy oil.

Even if you make a pulverized coal-oil mixture using only a single oil or a pre-blended oil, you can make a pulverized coal-oil mixture using a single oil (preferably petroleum crude oil or heavy oil), and then mix other oils. or mixed firing.

Water may be mixed into the pulverized coal overnight mixture, or added by the manufacturer or user. This is not preferable because it increases the heat of vaporization of the fuel and increases heat loss, so the lower the better.

On the other hand, water is allowed to be mixed in a small amount because it has the property of improving the stability of the pulverized coal and oil mixture and has the effect of reducing NOx and byzine in the exhaust gas during combustion.

Therefore, the total water content is preferably 9% by weight or less, preferably 6% by weight or less, and may not be contained at all.

However, when about 0.5% to 3% of water is added later together with the drug, stability is often significantly improved.

The additive for pulverized coal and oil mixture according to the present invention is (a)
Along with di- or mono- or di-mono mixed alkyl sulfosuccinates having an alkyl group having 6 to 10 carbon atoms in the molecule, (b) alcohols, amines, carboxylic acids having at least 3 or more active hydrogen atoms in the molecule, and their It is characterized by containing a polyether in which alkylene oxide is added to one or more derivatives as a starting material to have a molecular weight of 7,000 to 100,000.

Specific examples of the alkyl sulfo-citric acid ester salts described in section a) include the following.

Sodium dihexyl sulfosuccinate, mono-sodium hexyl sulfosuccinate, di-mono mixed sodium hexyl sulfosuccinate, di-n-octyl sodium sulfosuccinate, mono-n-octyl sodium sulfosuccinate, mono-di-mixed n-octylsulfosuccinate Sodium citrate, sodium di-2-ethylhexylsulfosuccinate, sodium mono-2-ethylhexylsulfosuccinate, sodium mono-di-mixed-2-ethylhexylsulfosuccinate, sodium di-n-decylsulfosuccinate, mono-n- Sodium decylsulfoconozoate, mono- and di-mixed sodium n-decylsulfosuccinate, di- or mono- or mono- and di-mixed sodium alkylsulfoconozoate obtained from alcohols having a carbon number distribution of 6 to 100.

In addition, monovalent metal salts such as ammonium salts and potassium salts corresponding to these K are also effective, but among them, di- or di-mono mixed salts are preferred, especially di- or di-mono mixed salts.
-Ethylhexylsulfosuccinic acid sodium salt is preferred.

Specific examples of the polyether compound described in (b) above will be described below.

The polyether mentioned here can be represented by the general formula ZC(RO)nH,lm, where 2 refers to alcohols, amines, carboxylic acids and their like having at least 3 or more active hydrogens, preferably 5 or more active hydrogens in the molecule. It is a residue of a derivative.

R is an alkylene oxide residue, such as an ethylene, propylene, butylene group, and n is a value determined by the degree of polymerization of the alkylene oxide.

m is the number of active hydrogens of 2, at least 3 or more,
Preferably it is 5 or more.

RO may be a single substance or two or more types thereof, and the arrangement order thereof may be a block copolymerization type or a random copolymerization type.

However, as a general rule, in the case of copolymer type surfactants,
A block copolymerization type is generally used, and preferably, ethylene oxide is added to make the end a hydrophilic group.

There are at least 3 or more active hydrogen atoms in the molecule indicated by Z.
Among the alcohols, amines, carboxylic acids, and derivatives thereof preferably having 5 or more hydrogen atoms, alcohols include alcohols having 3 active hydrogen atoms such as glycerin, butanetriol, hexanetriol, trimethylolpropane, triethanolamine, etc. Alcohols with 4 active hydrogens such as glycerin and pentaerythritol, sorbitan, sorbitol, glycose, sucrose, partially saponified polyvinyl acetate, partially saponified polyvinyl acetate copolymers, cellulose, starch, etc. with 5 active hydrogens Alcohols having the above are useful, and various derivatives such as partial esterification products of alcohols having four or more active hydrogens can also be used as long as three or more active hydrogens remain.

In addition, amines include amines having 3 active hydrogens, such as ammonia and tallow propylene diamine, and amines having 4 active hydrogens, such as ethylenediamine, tetramethylenediamine, hexamethylenediamine, phenylenediamine, penzidine, and cyclohexyldiamine. Amines having 5 or more active hydrogens, such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, etc., are useful, and even various derivatives such as partial amides of amines having 4 or more active hydrogens, It can be used if at least one active hydrogen remains.

In addition, carboxylic acids include carboxylic acids having three active hydrogen atoms, such as hemimellitic acid, trimellitic acid, and trimesic acid, and carboxylic acids having four active hydrogen atoms, such as butanetetracarboxylic acid, pyromellitic acid, and ethylenediaminetetraacetic acid. Carboxylic acids having 5 or more hydrogen atoms, such as acrylic acid polymers, acrylic acid copolymers, maleic anhydride polymers, maleic anhydride copolymers, me! Acrylic acid polymer,
Partially saponified products of methacrylic acid copolymers, polymers and copolymers of acrylic acid and methacrylic acid esters are useful, and various derivatives such as partially esterified products thereof can also be used.

Further, 2 may contain different types of functional groups in the same molecule.

For example, glycine, malic acid, monoethanolamine,
These include diethanolamine, tartaric acid, and aminoethylethanolamine.

The present inventors have already found that the drug described in (b) above exhibits an excellent effect, and a patent application is pending, but when these drugs are used in combination with the drug described in (a), an even more excellent effect can be obtained. I have found that it is effective.

In addition, the additive of the present invention can be used by dissolving it in a solvent, particularly a lower alcohol such as methanol, ethanol, ingropanol, n-7''ropanol, n-butanol, ethylceronelube, or a mixture of lower ercol and water. Although the effect is better when the solvent is used, it can also be used without using a solvent.

Furthermore, there is no hindrance to the combined use of other surfactants in appropriate amounts.

As is clear from the comparison in the examples below, mono- or di-alkyl sulfosuccinate salt alone,
It is not preferable because the stability of the pulverized coal and oil mixture is impaired, and it is essential to use the components described in (a) and the components described in (b) in combination, and the combination ratio is (a)/(b) - 95/5 ~ 5/95
, preferably << is 9 0/1 0 to 6 0/4 0 or 1
0/9 0 to 4 0/6 0.

In order to stabilize and fluidize a mixture of pulverized coal and oil using the additive of the present invention, the additive can be added after dry-pulverized pulverized coal is mixed into oil, or the additive can be dissolved in oil in advance. You can add dry-pulverized pulverized coal or mix all three at once.
, water may be added to each of them, or the additive may be added afterward to the wet-milled pulverized coal-oil mixture or after it is added to the oil. It's fine.

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 0.08% by weight in the mixed fuel.
˜0.8% by weight, and the upper limits of 5% and 0.8% by weight are simply values for economic reasons.

According to the present invention, when forming a dispersion system consisting of additives, pulverized coal, oil, and optionally water, any temperature is adopted, for example, mixing is performed at 50 to 120°C, and the mixing pressure is pressurized,
It may be used at normal pressure or during degassing under reduced pressure, and the stirrer and stirring conditions are not restricted as long as the action of the additive is not inhibited.
In particular, strong stirring at a circumferential speed of 2 m/see or more is preferred.

Next, the present invention will be explained in more detail with reference to Examples.

Note that all parts and percentages shown in Examples are based on weight.

Moreover, the rod penetration test shown in the following examples was conducted as follows.

As a test device, the inner diameter is 5.5CrrL and the height is 20CIrL.
stainless steel cylinder, 6cIrL from the bottom to the bottom
, 12 books are used that have an outlet with a stopper at each position.

Fill this cylinder with the specified mixed fuel to a height of 18 crfL from the bottom, cover the top of the cylinder with a lid with a guide hole in the center, and insert a glass rod with a smooth tip (5 mm in diameter) through the center guide hole. A total weight of 20 V) was dropped vertically, and the time from when the tip of the rod penetrated into the mixed fuel until it reached the bottom of the cylinder was measured, and this time was defined as the rod penetration time.

The shorter this time, the less sedimentation and compaction of pulverized coal, resulting in a mixed fuel with excellent fluidity.

After the test, remove the stopper at a position of 12 cIrL from the bottom, and check the mixed fuel above it (i.e., the mixed fuel in the cylinder at a height of 12 to 18 cIrL from the bottom).
was taken out and used as an upper layer sample, and its viscosity and coal concentration were measured.

Next, the stopcock at a position of 6 CrrL from the bottom was removed, and the mixed fuel above that point was taken, and its viscosity and coal concentration were measured as a middle layer sample.

Finally, the bottom stopper was removed, the remaining mixed fuel was collected, and its viscosity and coal concentration were measured as a lower sample.

Both the rod penetration test and viscosity measurement described above were conducted at 70°C.
I went there.

Example The prescribed amounts of coal, petroleum, additives and water shown in Table 1 were added to 1
After adding it to the e-container and stirring it by hand at 70°C for about 2 minutes,
Circumferential speed 3m/sec 70℃ using homomixer
A mixed fuel was obtained by stirring for 10 minutes under these conditions.

This product was subjected to a standing test at 70°C for 30 days, and then subjected to a rod penetration test and the viscosity and coal concentration of the upper, middle, and lower layers were measured.

The results obtained are shown in Table 1. From Table 1, this mixed fuel is transported by large tanker because the rod penetration time after the static test at 70'C for 30 days is the same as that immediately after production, and there is little change in viscosity or coal concentration before and after the test. It also shows that it can withstand long-term storage in tanks.

Reference Example A mixed fuel was obtained under the same conditions as in the example except that the dispersant was changed.

The properties of this product before the test and the results after a 30-day standing test at 70°C are shown in Table 2.

Table 2 shows that these mixed fuels cannot withstand transportation in large tankers or long-term storage in tanks because the coal separates and becomes compacted.

Claims (1)

[Scope of Claims] 1) di- or mono- or di-mono mixed alkyl sulfosuccinate salt having an alkyl group having 6 to 10 carbon atoms in the molecule; (b) at least 3 or more active hydrogen atoms in the molecule; A pulverized coal characterized by containing a polyether having a molecular weight of 7,000 to 100,000 by adding alkylene oxide to the starting material, starting from one or more of alcohols, amines, carboxylic acids, and their derivatives. Additive for single-oil mixtures.