JPH01271484A - Treating agent for coking coal - Google Patents

Abstract

PURPOSE:To provide a treating agent for coking coal excellent in an effect of improving the bulk density of coal, etc., by adding a specified amount of a specified fluorinated surfactant to a sodium or triethanolamine salt of a dialkyl sulfosuccinate. CONSTITUTION:A sodium or triethanolamine salt (A) of a dialkyl sulfosuccinate (e.g., sodium di-2-ethylhexyl sulfosuccinate) is mixed with 0.02-1wt.% anionic or nonionic surfactant (B) having a long-chain fluoroalkyl group in the molecule (e.g., sodium perfluoroalkylcarboxylate). When the obtained treating agent is sprayed on coal in the production of coke in, e.g., an ironworks, the adhesion, solidification, etc., of coal in handling apparatusses such as a hopper and a belt conveyor can be prevented without fail, and the packing density of an oven can be improved.

Description

Detailed Description of the Invention (Industrial Field of Application) This invention is directed to the prevention of adhesion in handling equipment such as coking coal hoppers and belt conveyors during coking coal production in steel plants, etc. The present invention relates to a treatment agent used for the purpose of preventing sticking and improving the packing density in a coke oven.

(Prior Art) It is known that the quality of coke, such as its strength, can be improved by increasing the amount of coking coal charged into a coke oven.

However, recently there has been a tendency to use coking coal with a high proportion of non-caking coal, but when trying to increase the amount of coking coal charged to the coke oven, it is difficult to transfer the coking coal to the coke oven. Blockage of hopper, adhesion to handling equipment such as belt conveyor, falling off from belt conveyor, etc.
Furthermore, a number of problems arise, such as insufficient bulk density for coke ovens.

In particular, when the moisture content of coking coal is high, the frictional force increases due to the surface tension of the moisture adhering to the surface of the coal particles, making it difficult for the coal particles to slip, which causes bridging and other problems when charging into a coke oven. This causes a decrease in bulk density.

In order to increase the amount of coking coal charged into the coke oven,
Conventionally, steel mills and the like have adopted a so-called oiling method in which mineral oils such as A, B, and C heavy oils or waste oils generated in large quantities in steel mills are added to coking coal.

Further, methods of adding a surfactant instead of mineral oil are disclosed, for example, in JP-A-5A-I+91S and JP-A-56-11.
This is reported in Publication No. 0892, etc.

(Problems to be Solved by the Invention) The oiling method described above forms an oil film on the surface of coal particles to reduce friction between coal particles, and prevents adhesion and sticking in handling equipment such as hoppers and belt conveyors, and prevents coke from sticking. This aims to improve the bulk density of the furnace.

However, although this method is somewhat effective when the moisture content of the coking coal is low, such as 6 to 8%, the amount of mineral oil added is 0. Since it reaches as high as .3 to 0.8z, there is a risk of ignition in the transfer line, and there is also the problem of mineral oil getting mixed into the waste water. Furthermore, since mineral oil containing relatively large amounts of sulfur and nitrogen is used, there are problems such as generation of harmful gases and irritating odors.

Additionally, if mineral oil is added to coking coal with a moisture content of over 8%, especially coking coal with a moisture content of IH or higher, hopper clogging and adhesion to the belt conveyor will increase, and the bulk of the coking coal charged into the coke oven will increase. There are problems such as a decrease in density.

On the other hand, the method of adding surfactants instead of mineral oil obtains a lubricating effect between coal particles by lowering the surface tension of the water adhering to the surface of the coal particles, which makes handling of hoppers, belt conveyors, etc. The purpose is to prevent adhesion and sticking in the equipment and to improve the bulk density of the coke oven.

In this method, anionic surfactants such as dialkyl (alkenyl) sulfosuccinates and alkylbenzene sulfonates, nonionic surfactants such as POE (7-14) alkyl ethers, POE (7-14) alkyl phenol ethers, etc. is being used.

Among these methods, the method using dialkyl sulfosuccinate as a surfactant provides superior effects compared to the conventional oiling method.

However, in recent years, many attempts have been made to mix as much slightly coking coal as possible into the coking coal charged to coke ovens, and as a result, more than 50% of the coking coal is made up of fine particles with a grain size of less than 1 mm. However, for such raw material coal, anionic surfactants have the disadvantage that they do not have the expected bulk density improvement effect.

For example, fine particles with a particle size of 1■■ or less are 50z
Experimental results have also been reported that show that anionic surfactants are inferior to the above-mentioned nonionic surfactants in terms of the bulk density improvement effect of raw coal, which also accounts for the above.

Therefore, in this invention, as a result of intensive research aimed at improving a treatment agent for raw coal for coke production that mainly contains dialkyl sulfosuccinate among anionic surfactants, we found that It has been discovered that by blending an anionic or nonionic fluorosurfactant having a group, a sufficient bulk density improvement effect can be seen even in fine raw coal having a particle size of 11 or less.

(Means for Solving the Problems) In this invention, based on the above findings, zero anionic or nonionic fluorosurfactant having a long-chain fluoroalkyl group in the molecule is added to the sodium salt or triethanolamine salt of dialkyl sulfosuccinic acid. This paper proposes a treatment agent for raw coal for coke production containing .02 to I Wt$.

Specifically, the dialkyl sulfosuccinate used as the main component in this invention includes alkyl groups such as 2-ethylhexyl, n-hexyl, n-octyl,
Examples of the n-decyl salt include Na, triethanolamine, and the like.

Nonionic or anionic fluorosurfactants having a long-chain fluoroalkyl group in the molecule used in this invention include, for example, sulfonate, carboxylate, acid Using amide, phosphate ester, ethylene oxide, etc. as the parent group, sodium, potassium, ammonium, mono,
It is composed of di- or triethanolamine as a salt, such as sodium perfluoroalkyl carboxylate, perfluoroalkyl ethylene; oxide adduct, perfluoroalkyl ethylene oxide adduct,
Examples include perfluoroalkyl phosphate potassium salt, perfluoroalkylsulfonic acid triethanolamine, and perfluoroalkylsulfonamide.

This invention is characterized in that a fluorine-based anionic or nonionic surfactant having a long-chain fluoroalkyl group is blended into the dialkyl sulfosuccinate, and the blending ratio thereof has an optimum range. A small addition of about 0.02 to 1 wt% to the salt may be sufficient.

If the amount of the fluorosurfactant added is 0.02 Wtl or less, the effect of the addition will not appear on the bulk density value, which is almost the same as the value of dialkyl sulfosuccinic acid alone. - On the other hand, if the IWt is 1 or more, the bulk density value remains unchanged, and there is no need to add more fluorine surfactant.

The treatment agent according to the present invention may be added at any step from the pulverization of the coking coal to the charging into the furnace.
It may be about Oppm or more, preferably 200-1000
Satisfactory effects can be obtained by adding as much as PP.

As for the addition method, the bulk density improver according to the present invention is added by spraying or the like, either alone or diluted with water as appropriate, in any of the mixing, pulverizing, and furnace charging coking coal transfer lines of coking coal for coke production. Here are some methods.

As a special example, sufficient effects can be obtained by suspending and dispersing it in oil, which corresponds to the conventional oiling method.

Furthermore, when the treatment agent according to the present invention is added to water, it may cause gelation, which may impede cleaning of chemical supply tanks, supply piping, etc. at work sites. When ethylene glycol is added, it can be dissolved in water in a short time. In this case, the appropriate amount of ethylene glycol to be added is 10 to 30 Wtl relative to the processing agent according to the present invention.

(Effects of the Invention) In summary, since the treatment agent according to the present invention has a dialkyl sulfosuccinate as its main component, it can be used in coking coal hoppers and belts during coking coal production in steel plants, etc. while charging coking coal into coke ovens. Reliably prevents adhesion and sticking in handling equipment such as conveyors.

Further, the treatment agent according to the present invention has a dialkyl sulfosuccinate containing a long-chain fluoroalkyl group in one molecule.
Since it contains anionic or nonionic surfactant, compared to dialkyl sulfosuccinate alone,
For example, it is possible to improve the bulk density of fine coking coal having a grain size of 1 layer or less.

Therefore, by using the processing agent according to the present invention, stable operation can be achieved at all times when using coking coal for coking that contains a large amount of fine coal particles or poor brand low/slightly caking coal. Coke can be produced under certain conditions.

(Example) Examples of this invention will be shown below.

Support 1 base 1 leak Combination example 1 Di-2-ethylhexylsulfosuccinate sodium 99.981t$
Sodium perfluoroalkylcarboxylate (C=8”) 0.02W
t$ Formulation Example 2 Di-n-octyl sulfosuccinic acid triethanolamine 99.6 Wt$
Polyoxyethylene perfluoroalkyl ether (E
Number of moles of O added 12 (: -8) 11.41t%
Formulation example 3 Sodium di-n-decyl sulfosuccinate 99.3Wtl
Perfluoroalkylsulfonic acid triethanolamine (C rich 15) 0.7Wt
lFormulation example 4 Sodium di-2-ethylhexylsulfosuccinate 99.0Wt$
Perfluoroalkylsulfonamide (C-6) 1. ．． 0W
Comparative Example I A Heavy Oil Comparative Example 2 B Heavy Oil Comparative Example 3 Sodium dodecylbenzenesulfonate Comparative Example 4 Sodium di-2-ethylhexylsulfosuccinate Comparative Example 5 Sodium Coconut Fatty Acid Comparative Example 6 Lauryl Alcohol Sulfate Ester Na Salt Comparative Example 7 POE (12) Nonylphenol Ether Comparative Example 8 POE (14) Nonyl Phenol Ether Comparative Example 9 POE (12) Lauryl Ether Comparative Example 10 POE (12) Nonyl Phenol Ether Phosphate Comparative Example 11 Perfluoroalkyl sulfonamide (C- 8) Comparative Example 12 POE (12) Octyl Ether Comparative Example 13 POE (12) Oleyl Ether The following various tests were conducted on the above-mentioned processing agent of the present invention and comparative example.

Example 1 The bulk density improving effect of the following sample coals was evaluated in the following manner using the treatment agent of the present invention and the treatment agent of the comparative example.

[Test charcoal] The charcoal to be tested was pure Intet produced in Canada.
After sieving, only particles with a particle size of 1 square inch or less were used.

[Test method] From the upper end of a cylindrical stainless steel container l with an inner diameter of 67 mm, an outer diameter of 72 mm, and a height of 500 weight, the lower end of which was sealed, dry weight of 700 g, moisture content of 8z, 10%, and 12% was measured. The treatment agent of the present invention and the conventional treatment agent added in the proportions shown below were added to the test coal (charcoal type: single Intet from Canada), and the mixture was evenly dropped and filled, and the surface was carefully flattened. Leveled and read the filling height.

Next, using a tapping device 2 as shown in Fig. 1, the container 1 is lifted up to a tapping height h (70 cm) and tapped five times, the filling height is read, and the bulk density is determined by dry-coal g. It was calculated from the following formula as /c■3 value.

Bulk density = (g/cm”)
Occupied water-containing volume when tapped 5 times This test was repeated three times, and the average value of the bulk density was determined. In addition, the average value of the density of 5.4゛ was determined in a similar manner for the sample coal without the addition of a treatment agent.

The results are shown in Table 1 below.

Table 1 From these results, for raw coal with a fine particle size of 11cm or less, the bulk density improvement effect is better when using a nonionic surfactant than an anionic surfactant. However, when a fluorine-based surfactant is blended with an anionic surfactant such as a dialkyl sulfosuccinate as in this invention, the bulk density of raw coal with a fine particle size of 1 cm or less is greatly improved, and nonionic 4, which surpassed surfactants.
Example 2 The effect on bulk density was evaluated for the following sample coal using the same apparatus and method as in Example 1 using the treating agent of the present invention and the treating agent of the comparative example.

Treatment agent of the present invention [Test coal] Coal type A: Mixed coal of 60% Quintet from Canada and 40% Tramont from the United States, sieved to be 31 or less before testing Coal type B: Made in Canada Quintet 25z, Australian postpartum (color, blackwater, Hoskisson, Moller, etc.) 45
z, Mixed coal of Obtainum SL from South Africa and Drummond 251 from the United States was sieved prior to the test and the results are shown in Figure 2 below. From these results, the treatment agent according to the present invention can It has been found that in both A and B, better results can be obtained than in the conventional cooling method or in the case of adding a conventional treatment agent consisting of a surfactant.

Table 2 Example 3 After adding a predetermined amount of water to completely dried Canadian intet and IO mesh under and thoroughly mixing,
The processing agent of the present invention and the conventional processing agent of the above formulation example were added and mixed again. 5 g of the sample prepared in this way was placed on a stainless steel test piece (70 mm) as shown in Figures 2 and 3.
x 150maxims) 3 in an area of 6cm x 4cm by compaction and molding for 1 minute under a load of Ikg. The test piece 3 with the sample coal 4 molded in the center in this way was tilted at a speed of 3°/sec using the motor 5 with its rear end as a fulcrum.

The inclination angle of the test piece 3 when the sample coal 4 slid toward the fulcrum was read, and the results are shown in Table 3. From these results, even in the consolidated state, blending examples 1 to 4 were superior to the conventional ones. It is clear that it exhibited superior slipping effect compared to other surfactants.

Table 3 Example 4 A hopper device as shown in FIG. 4 was prepared assuming a field device, and a test was conducted to determine the passage rate of the sample coal through the hopper.

[Hopper device used in the test] The hopper device used in the test was made of stainless steel and had a
A prismatic container 6 measuring 3 x 13 x 15 cm, a prismatic section 7a measuring 15 x 15 x 5 cm at the middle end, and a height lsc++
+, exit diameter 5 x 5cta 0) fIIa diameter section 7
b and Kara; 5 hoy huff and 13X 13x at the bottom
It has a dendritic container 8 of 15c+*, a container 6 and a hopper 7.
A shutter 9 made of stainless steel plate is provided between them.

[Test charcoal] Intet produced in Canada, sieved 3+*m or less [Test method] In container 5, dry weight equivalent to 700 g, moisture content 8z, 1
0% and 12114% test coals were filled (bulked) with the treatment agent of the present invention (formulation example 1.2) and conventional treatment agents (comparative examples 1 and 3.4.7) added in the following proportions. density 0.600
wet-coal g/c+s3) After L/, S'F
The twine plate 9 was pulled out at once and the sample coal was dropped into the hopper 7, and the weight of the coal that passed through the hopper 7 and flowed out from the lower outlet was measured. This test was performed three times.

The average weight of the sample charcoal flowing out from the outlet of the hopper 7 into the container 8 was measured to determine the passage rate of the sample charcoal in the hopper.

In addition, similar tests were conducted on products without the addition of processing agents, and the results are shown in Cloth 4 below.

As is clear from the results, the processing agent of the present invention exhibited an excellent hopper passage rate compared to the conventional processing agent.

[Brief explanation of the drawing]

FIG. 1 is a side view showing the bulk density measuring method in Examples 1 and 2 of the present invention, FIG. 2 is a side view of the measuring device used in Example 3, FIG. 3 is a plan view of the same, and FIG. The figure is implemented
It is a longitudinal side view of the hopper device used in No. 44. Patent applicant: Taiho Industries Co., Ltd.

Claims (1)

[Claims] An anionic or nonionic fluorosurfactant having a long-chain fluoroalkyl group in the molecule is added to the sodium salt or triethanolamine salt of dialkyl sulfosuccinic acid.
．． A treatment agent for raw coal for coke production, characterized in that it contains 02 to 1 wt%.