JPS638487A - Carbonaceous solid-water slurry composition - Google Patents

Abstract

PURPOSE:The titled inexpensive composition having improved stability, not being influenced by kinds of eluted inorganic salts, difference in concentration and difference in pH, having good fluidity, etc., obtained by combining a carbona ceous powder with a specific dispersant and a stabilizer and using. CONSTITUTION:A carbonaceous solid water slurry composition comprising (A) carbonaceous solid powder such as coal oil coke, petroleum pitch, etc., (B) a dispersant of a sulfonated substance (salt) of nephthalene or cresote oil or an aliphatic aldehyde addition condensate thereof and/or an aliphatic aldehyde condensate (salt) of sulfonic acid-containing aminotriazine, (C) a stabilizer consisting of clay minerals and/or xanthan gum and (D) water as main components.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a low-cost carbonaceous solid/water slurry m-acid which has good fluidity, excellent stability, and can be directly combusted. .

(Conventional technology) In recent years, due to the instability of oil supply, technology development has been progressing to effectively utilize carbonaceous solids such as coal, oil coke, and petroleum-based pinch. Various technologies can be considered, such as pyrolysis, gasification, combustion, alternative fuels for heavy oil injected into blast furnaces in the steel industry, and alternative fuels for heavy oil in cement kilns. Because it is solid at room temperature, it is difficult to handle, and
It has disadvantages such as the risk of pollution due to dust scattering and the risk of powder-induced explosion, making it difficult to use.

Therefore, it is desirable to convert these carbonaceous solids into fluids to facilitate handling and prevent pollution and danger. On the other hand, in order to reduce the cost of transporting carbonaceous solids, it is effective to transport them in the form of a fluid.

For the purpose mentioned above, it is effective to make a slurry as a method of fluidizing carbonaceous solids, but this slurry can be thermally decomposed, gasified, combusted, or blown into a blast furnace.
In order to use the slurry as a fuel for cement kilns, it is necessary to make the slurry highly concentrated and to prevent solid particles suspended in the slurry from settling and causing solid-liquid separation.

Conventionally, as a stable coal/water slurry composition, a slurry composition consisting of particle size-adjusted coal, a thickener, a surfactant, and water, coal, an alkali metal salt of a specific anion,
Slurry composition consisting of surfactant and water, JP-A No. 1987
As shown in Publication No. 9-100191, solid fuel,
A slurry composition consisting of an alkali metal salt of lignin sulfonic acid, an alkali metal salt of carboxymethyl cellulose (CMC), and water, as shown in JP-A-59-4691, a carbonaceous material, naphthalene sulfonate,
Slurry compositions consisting of karaya gum and water are known.

[Problem that the invention seeks to solve]

However, the above-mentioned conventional coal/water slurry does not have satisfactory stability in practical use, and the cost of the dispersant is high and the amount of stabilizer added is large, so it has the problem of increasing cost. It existed.

In view of the above points, the present inventors conducted intensive research on carbonaceous solid/water slurry compositions and found that a stabilizer selected from the group consisting of an alkali metal salt of carboxymethyl cellulose, hydroxyethyl cellulose, or sodium polyacrylate. It was discovered that the combination of one or more of these and a dispersant has a remarkable stabilizing effect, and that the addition rate of other stabilizing agents decreases. Based on this, the patent application No. 6
Patent applications were filed as No. 0-183340, Japanese Patent Application No. 183341-1980, and Japanese Patent Application No. 2660-1983.

However, subsequent research has shown that, depending on the type of carbonaceous solid, especially the type of coal, the stabilizing effect may be reduced due to inorganic metal salts eluting from the coal or changes in the pH of the slurry caused by these. I found out that. Therefore, as a result of conducting research on combinations of dispersants and stabilizers that are effective for these types of coal, we have found that the following combination can provide a stabilizing effect relatively regardless of the type of coal. I found out.

That is, the dispersant is selected from the group consisting of sulfonated products of naphthalene or creosote oil, salts thereof, or aliphatic aldehyde addition condensates thereof, or aliphatic aldehyde condensation products of aminotriazine containing sulfonic acid groups, or salts thereof. The stabilizing effect can be obtained by using a compound consisting of clay minerals, especially bentonite or palygorskite of the montmorillonite group, or xanthan gum as a stabilizer, and by combining the above-mentioned dispersant and stabilizer. It has been found that the stabilizing effect can be obtained without being significantly influenced by the type of eluted inorganic salt, the degree of concentration, or the difference in pH depending on the type of coal.

The present invention was made based on the above findings, and aims to provide a carbonaceous solid/water slurry composition that is inexpensive and has good fluidity and stability.

[Means for solving problems]

The carbonaceous solid/water slurry composition of the present invention has the following (8)
1 to (4 components of dl, i.e. +a+ Carbonaceous solid powder such as coal, oil coke, petroleum pitch, etc.) Sulfonated products of naphthalene or creosote oil, salts thereof, or aliphatic aldehyde addition condensates thereof, or One or more dispersants selected from the group consisting of aliphatic aldehyde condensation products of sulfonic acid group-containing aminotriazines or salts thereof; [One or two stabilizers consisting of C1 clay minerals or xanthan gum; As mentioned above, the main component is (dl water).

Further, the proportion of each composition of the carbonaceous solid/water slurry composition of the present invention is as follows: +al Carbonaceous solid powder such as coal, oil coke, petroleum pitch: 40 to 90% by weight, preferably 65 to 90% by weight
75% by weight ('b) Dispersant: 0.01-5% by weight, preferably 0
．． 2-1.0% by weight [C1 stabilizer: 0.0001-2.0% by weight, preferably 0.001-0.5% by weight (d+ water = 10-60% by weight, preferably 25-3
It is 5% by weight.

Examples of the dispersant include sulfonated products of naphthalene or creosote oil, salts thereof, or aliphatic aldehyde addition condensates thereof, or aliphatic aldehyde condensation products of aminotriazine containing a sulfonic acid group, or salts thereof. As the salts of these sulfonates, salts of alkali metals such as sodium and potassium, salts of alkaline earth metals such as calcium and magnesium, and ammonium or amine salts can be used. These dispersants may be those obtained by addition condensation of a sulfonated product with an aliphatic aldehyde, or those obtained by addition condensation with an aliphatic aldehyde and then sulfonation, and among these, those obtained by condensation with formalin are particularly effective. The degree of condensation is preferably 1.2 to 3o, more preferably 1.2 to lO.If the degree of condensation is less than 1.2, the effect of condensation will be small, and if it exceeds 30, the molecular weight will increase, resulting in poor solubility. It is not practical in this respect.

The "creosote oil" used in the present invention refers to a neutral oil with a boiling point of 200°C or higher in coal carbonization tar or an alkylated product thereof. Conventionally, creosote oil has been defined in various ways, but according to Japanese Industrial Standard JISK 2439. (19
According to 78), it is a mixture of distillate oils higher than medium oil obtained by distilling coal tar, and crystals such as naphthalene and anthracene are separated from each fraction such as medium oil, heavy oil, and anthracene oil, and phenols and pyridine are separated. A product that is separated and collected, and then appropriately blended with those distillates to meet a certain standard. For example, creosote oil, which is classified into three types, No. 1, No. 2, and No. 3. No. 1 has a specific gravity of 1.0
3 or more, moisture 3% or less, boiling point 235℃ or less 25%
Hereinafter, it is a mixture of various compounds in which 40% or more of the compounds have a boiling point of 235 to 315°C and 50% or more is distilled out at 315°C or lower.

As starting materials for producing the dispersant in the present invention, creosote oil specified in JIS K 2439 (197B) may be used as a mixture of various components, or a fraction obtained by fractionating the creosote oil, such as Boiling point 200-25
0℃, 240~260℃, 250~270℃, 270~
All fractions such as 300°C can be used. It is also possible to use alkylated creosote oils and fractions. The alkylation method is not particularly limited.

There is also a method in which sulfonation using fuming sulfuric acid or concentrated sulfuric acid is carried out at the same time by allowing the corresponding alcohol to coexist.

Further, the condensation product of aminotriazine containing a sulfonic acid group and an aliphatic aldehyde used in the present invention is amino-s
- a triazine condensate. One example is the special public service 1977-2.
This is a condensate produced by the technique described in Japanese Patent No. 1659. These condensates are generally prepared in the presence of an aliphatic aldehyde, preferably formaldehyde.
3-triazine, such as melamine, hexamethylolmelamine, acetoguanamine or benzoguanamine, and then using a sulfonating agent such as sulfite, sulfuric acid, sulfonic acid, bisulfite or their salts, dithionite, dithionite, pyrosulfite, etc. The sulfonated melamine resin, which is a preferred embodiment of the present invention, is obtained by condensing amino-3-triazine sulfonic acid with an aldehyde, preferably formaldehyde. It is a sulfonic acid group-containing condensation product obtained by adding NaH3O1) and reacting it.

As a stabilizer, it is preferable to use clay minerals, especially montmorillonite group and/or xanthan gum.

However, as a clay mineral, i.e., a hydrated alumina silicate,
In addition to the montmorillonite group, it is also possible to use kaolin group, illite group, etc.

〔Example〕

Examples and comparative examples will be described below.

Comparative Example 1 After coarsely pulverizing coal having the properties shown in Table 1 to 31 or less, various dispersants shown in Table 2 were added to water in an amount of 0.7% by weight based on the coal, and this aqueous solution and Coarsely pulverized coal is continuously fed to a wet mill and pulverized and mixed, resulting in a coal concentration of 66% by weight.
Particle size is 200mesh pass (74μ or less) 85
A slurry with a concentration of ±2% was produced. After putting this slurry into the static tank 1 shown in the drawing, a small amount of sample is periodically taken out from the sampling outlet 2.3.4 of the upper, middle, and lower layers, the concentration is analyzed, and the status of sedimentation separation is investigated. Ta. 5
is a coal-water slurry. Note that the unit of numerical value is mm.

Part of the test results in Table 4 (portion with stabilizer addition rate O)
As a result of the static tank test shown in , the period during which the difference in the concentration analysis values of the slurry samples taken out from the upper layer and the lower layer was within 2% by weight was defined as the stable period.

(Margins below) Table 1 Table 2 Example 1 A slurry produced in the same manner as in Comparative Example 1 (to which a dispersant was added in the same manner) was placed in a stirring tank, and various stabilizers shown in Table 3 were added to the slurry. 0.005% by weight of curing agent per coal, 0
．． 01 M amount%, 0.02% by weight, 0.05% by weight, 0
, 1% by weight, and 0.3% by weight were added and mixed, and the stabilized slurry was placed in the static tank shown in the drawing, and the status of sedimentation and separation was investigated. The test results are shown in Table 4.

Table 3 (blank below) Table 4 Example 2 Coal having the properties shown in Table 5 was pre-pulverized to a particle size of 4 cranes or less and 9594 particles, and then 0.8% by weight of naphthalene-based anionic dispersant based on the coal was added. (Table 2 1D-1) was supplied to a wet mill and pulverized and mixed to produce a 67% by weight slurry. Furthermore, after adding and mixing 0.01% by weight of xanthan gum based on coal to this slurry, physical properties were measured and stability was evaluated using a standing tank 1 shown in the drawing. The results are shown in Table 6.

Table 5 Example 3 A 67% by weight slurry was produced in the same manner as in Example 2 using a naphthalene-based anionic dispersant (Table 2 1hD-2) of 0.8% by weight based on coal.

The results are shown in Table 6.

Example 4 A 67% by weight slurry was produced in the same manner as in Example 2 using 0.8% by weight of naphthalene-based anionic dispersant (Table 2 11 & tD-3) based on coal.

The results are shown in Table 6.

Comparative Example 2 Coal having the properties shown in Table 5 was coarsely pulverized in advance to a particle size of 95% of 4 richness or less, and then a 0.8% by weight aqueous sodium ligninsulfonate aqueous solution was used to prepare a slurry by weight. After adding and mixing xanthan gum in an amount of 0.01% by weight based on the coal, physical properties were measured and stability was evaluated using the standing tank 1 shown in the drawing. The results are shown in Table 6.

(The following is a blank space) Table 6 Example 5 Coal having the properties shown in Table 7 was coarsely ground in advance to a particle size of 85% below 3-grain, and then fed to a wet ball mill with water so that the slurry concentration was 40% by weight. Particle size is 200mes
The powder was pulverized to a particle size of 80% less than h, and particles larger than 200 μm were removed using a vibrating sieve. Next, this slurry was dehydrated using a belt filter to reduce the total water content to 30%, and then a naphthalene-based anionic dispersant (Table 2 1hD 2) of 0.7% by weight based on coal and 0.2% by weight based on coal
Palygorskite and slurry concentration of 68%
A high concentration slurry was produced by adding water in an amount of % by weight and mixing with a kneader.

Table 8 shows the results of measuring the physical properties of the product slurry and evaluating the stability using the standing tank 1 shown in the drawing.

Table 7 Comparative Example 3 Coal having the properties shown in Table 7 was coarsely pulverized in advance to a particle size of 31 or less and 85%, and then fed to a wet ball mill with water so that the slurry concentration was 40% by weight, and the particle size was 200mesh.
The slurry was ground to 80%, and particles of 200 μm or more were removed using a vibrating sieve. This slurry was then dehydrated using a belt filter to reduce the total water content to 25%.
To this, while adding 0.7% by weight of sodium origenin sulfonate (1kD-4 in Table 2) based on coal, palygorskite at 0.2% by weight based on coal, and water in an amount such that the slurry concentration is 67% by weight, A highly concentrated slurry was produced by mixing with a mixer.

Table 8 shows the results of measuring the physical properties of the product slurry and evaluating the stability using the standing tank 1 shown in the drawing.

Table 8 [Effects of the Invention] As explained above, according to the present invention, it is possible to reduce the amount of stabilizer added, and even if the type of carbonaceous solid is different, the effect is stable for a long period of time. It is possible to obtain the excellent effect of reducing costs.

[Brief explanation of drawings]

The drawing is an explanatory diagram of a stationary tank used in Examples and Comparative Examples. 1...Stationing tank, 2.3.4--Sampling outlet,
5.-Coal/water slurry

Claims (1)

[Claims] 1. The following four components (a) to (d), namely (a)
Carbonaceous solid powder such as coal, oil coke, petroleum pitch, etc. (b) Sulfonated products of naphthalene or creosote oil, salts thereof, or aliphatic aldehyde addition condensates thereof, or aliphatic aldehydes of aminotriazines containing sulfonic acid groups one or more dispersants selected from the group consisting of condensation products or salts thereof; (c) one or more stabilizers consisting of clay minerals or xanthan gum; and (d) water. A carbonaceous solid/water slurry composition characterized by comprising: