JPS59100191A - Preparation of aqueous slurry of solid fuel - Google Patents

Abstract

PURPOSE:To prepare an aqueous slurry of fuel oil with low viscosity, high concentration and excellent storage stability, by using as dispersant an alkali metal salt of ligninsulfonic acid and an alkali metal salt of carboxymethylcellulose. CONSTITUTION:A combination (A) alkali metal salt of ligninsulfonic acid and (B) alkali metal salt of carboxymethylcellulose is used as dispersant in the production of a solid fuel/water slurry by mixing a solid fuel (e.g. pulverized petroleum coke or deashed coal) into water. The resultant slurry has low viscosity and high concentration and shows excellent storage stability without causing sedimentation and densification of solid fuel even after a long period of storage. (A) and (B) are used in amounts of 0.05-0.6 and 0.03-0.5pts.wt., respectively, per 100pts.wt. slurry.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a solid fuel-water slurry with excellent storage stability.

More specifically, the present invention relates to an improvement in a method for producing a solid fuel-water slurry by mixing solid fuel such as coal and petroleum coke with water and a dispersant. By using a combination of an alkali metal salt of an acid and an alkali metal salt of carboxymethylcellulose.

The present invention relates to a method for producing a solid fuel-water slurry having low viscosity, high concentration, and excellent storage stability in which the solid fuel does not settle or become compacted even during long-term storage.

In recent years, solid fuels such as coal and petroleum coke have been reconsidered as energy sources. However, coal-1 petroleum coke and the like have the disadvantage that they are difficult to transport and store smoothly compared to fluid fuels such as petroleum-4, and are less efficient in handling and are more difficult to use than petroleum-1. Therefore, in order to improve these drawbacks, efforts are being made to develop a method in which solid fuel is pulverized and dispersed in water to form a solid fuel-water slurry.

However, when producing a solid fuel-water slurry, in general, increasing the solid fuel concentration significantly increases the viscosity of the slurry, resulting in loss of fluidity and difficulty in pipe transportation. On the other hand, if the viscosity of the slurry is increased/the concentration of solid fuel is decreased by the
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There is a drawback that a dehydration step is required.

A number of methods have been proposed to solve these problems and to add and mix a dispersant into the slurry to produce a low-viscosity, high-concentration 1-water slurry. When the slurry produced by Jl et al.'s method is allowed to stand still for a long period of time, a strong solid sediment layer is formed due to dehydration, and redispersion is often not easy. If you try to increase the slurry viscosity, not only will the viscosity of the slurry increase significantly.

Storage stability also deteriorates, making it difficult to produce a solid fuel-water slurry with low viscosity, high concentration, and excellent storage stability.

For example, a sodium salt of lignin sulfonic acid is used alone as a dispersant (7/in this case, it is possible to increase the concentration to some extent by increasing the amount added), but if the solid fuel concentration is If you try to increase the slurry to -, the viscosity of the slurry becomes extremely high and thick, making it difficult to produce a sweet slurry. Solid fuel sedimentation occurs between the slurry, making it impossible to stabilize the slurry. 1. Even if carboquine methyl cellulose sodium salt is used alone as a dispersant, the viscosity is low and the concentration is high.
(Unable to produce solid fuel-water slurry with good storage stability).

For example, as a dispersant, lignin sulfonic acid
2 types of salt and sodium salt of carbogine methyl cellulose, 2 types of sodium salt of lignin sulfonic acid and borif'crylamide, carbogine methyl cell 1-s and sodium β-naphthalene sulfonate Using two types of polymerin condensates, etc./
In this case, the solid fuel may settle in a short period of time (1t4), or if you try to increase the concentration, the viscosity of the slurry will increase significantly, making the concentration difficult to achieve (1), or the storage stability may deteriorate. Therefore, it is not possible to produce a solid fuel R-water slurry with low viscosity, high concentration, and excellent storage stability.

In addition to the method of using a dispersant, methods have also been proposed in which a solid fuel-water slurry is produced by adjusting the particle size distribution of the solid fuel, but the storage stability of the slurry cannot be improved by adjusting the particle size distribution. It is not easy to do or dissolve.

In view of these circumstances, the present inventors developed a low viscosity product.

With the aim of developing a practical solid fuel-water slurry with high concentration and excellent storage stability, we conducted extensive research and found that among the many known dispersants, In particular, by selecting an alkali metal salt of lignin sulfonic acid and an alkali metal salt of carboxyl methylcellulose and mixing them with a solid fuel and water to produce a solid fuel-water slurry, it is possible to create a slurry that can achieve the following objectives. Knowing that this could be obtained, I came up with the present invention.

The present invention provides a method for producing a solid fuel-water slurry by mixing solid fuel with water and a dispersant.

The present invention relates to a method for producing a solid fuel-water slurry, characterized in that an alkali metal salt of lignin sulfonic acid and an alkali metal salt of carboxymethylcellulose are used as the reagents.

The solid fuel-water slurry produced according to the present invention [.

It has a low viscosity, high concentration of homogeneous fuel, and can be stored for a long period of time. Therefore, the solid fuel-water slurry according to the present invention can be used as fuel and L2 in waste, boilers, power plants, etc., without requiring special equipment for tank storage.
It is suitable for use as a gasification feedstock, such as in the production of hydrogen, carbon oxide, etc.

In the present invention, it is particularly important to use both an alkali metal salt of ligninsulfonic acid and an alkali metal salt of carboxymethyl cellulose. However, if an alkaline earth metal salt is used, it is difficult to achieve the object of the present invention.

In the present invention, the alkali metal salts of lignin sulfonic acid include thorium salts, potassium salts, etc. .05~0.6 heavy h1 part,
Light j or C1,1 to -o, is used in the range of 5-fold attachment. If the amount used is too small, the solid fuel concentration cannot be sufficiently sieved, and if it is too large, the solid fuel concentration will not be further increased by reducing the amount of stool to 4, but there will be no economic effect. Therefore, it is preferable to use the alkali metal salt of lignin sulfo/acid within the above range.

-The alkali metal salts of carbogine methylcellulose include υJLsu1riuno, salt, kariuno, salt, etc., and the -7-alkali metal salts of carbogine dimethylcellulose are sura l) 1o c) For the heavy axillary region. Te 0.0
It is used in the range IJJJ of 3-0.5 M parts, preferably 0.05 to 0.3 parts by weight. If the amount of 41 used is too little, the storage stability will not be sufficient, and if it is too much, the slurry viscosity will increase and it will be difficult to produce a slurry with a high solid fuel concentration. It is better to do so.

Solid fuel used according to the present invention and 17.

Petroleum coke produced as a by-product from petroleum refining processes, deashed coal, etc., with an ash content of about 6 wt. 111% or more are suitable. Coal with a high ash content tends to inhibit the production of a highly concentrated solid fuel-water slurry.

Deashed coal can be easily obtained in step 1) by deashing commonly available commercially available coal by a method known per se such as heavy liquid coal washing. In addition, when coal is used as a solid fuel, there are no particular restrictions on the type of coal.4For example, lignite, :ff
1lW evening charcoal, historical charcoal, anthracite, etc. can be used.

Considering the reactivity and combustibility of the solid fuel-water slurry, the particle size of the solid fuel H is preferably such that the average diameter is 150 μm or less, preferably 74 μm or more.

In carrying out the invention, the mixing order d of the solid fuel, water, alkali metal salt of lignin sulfo/acid, and alkali metal salt of carboxymethylcellulose is not particularly limited i.
No. An example of a suitable preparation method is to first dissolve an alkali metal salt of lignin sulfonic acid and an alkali metal salt of carbogin methylcellulose in water, then add finely powdered solid fuel, and wet-pulverize the solid fuel I. A method of mixing can be mentioned.

Next, the present invention will be explained by showing examples and comparative examples. .

The volatile content was 11.2% by weight and the fixed carbon was 87.9% by weight.

The solid fuel-water slurry was produced on each side using the following method. 1. A few liters of dry-ground solid fuel with an IJ average diameter of about 7o/1m was further mixed into a powder with an IJ average diameter of about B11yn. A mixture of wet-pulverized solid fuel T1 at a weight ratio of 60:400 on an absolute dry basis was added to water in which a dispersant had been dissolved in advance, and 3D was added using a lab body spar (manufactured by Tokushu Kika Kogyo). A solid fuel-water slurry was prepared by stirring at 00 r, p, m for 6 minutes, and the slurry viscosity was measured with a B-type viscometer (manufactured by Tokyo dIki).

In addition, a storage stability test of solid fuel-water slurry C11 was carried out using the following method (1) and (2).

(1) A simple method in which a solid fuel-water slurry is charged into a 100 mg Sansol tube container, left to stand for a predetermined period of time, and then a glass pellet is inserted to examine the presence or absence of a settling part near the bottom of the container and the degree of compaction. The evaluation was rated as ◯ if there was no settling part and × if there was.

(2) With an inner diameter filter brnml and a height of 180 mm, there is a lower layer extraction "1. Middle layer extraction 60 mm above from the lower layer extraction L1" at the bottom of it, and an upper layer extraction [] 60 mm above the middle layer extraction port. In the bottomed cylindrical tube container provided.

A solid fuel-water slurry) is charged, and after allowing it to stand still for a specified period of time, the slurry in the soil layer, middle layer, and lower layer is taken out.

Method of measuring solid fuel concentration and slurry viscosity at each part.

Examples 1 to 2 A dispersant and two types of lignin sulfonic acid salt and carboxymethylcellulose salt were used in amounts listed in Table 1, and a solid fuel was used at 0 or 10 degrees Celsius. The petroleum coke-water slurry r) described in the table was manufactured, the slurry viscosity was measured, and the slurry was measured. The results are shown in Table 1.

Comparative Examples 1 to 7 Sodium salt of ligninsulfonic acid alone, carbogyzomethyl 1+b*- in the amounts listed in Table 1 as a dispersant.
x'nof') Using lamb salt alone, lignin sulfonic acid, sodium salt of lignin sulfonic acid and polyacrylamide, and calcyano salt of lignin sulfonic acid and sodium salt of carboxymethylcellulose. 2. 5. Produce a petroleum coke-water slurry whose solid fuel concentration is listed as F in Table 1. Measure slurry viscosity. The results are shown in Table 1.

＼、＼Table 1 In Table 1, CMC means carboxymethino[cellulose sodium salt.

Table 1 shows that according to the present invention, a slurry having a solid fuel concentration of 70% by weight or more and a viscosity of about 2000 cp can be produced (Example 1=2).

Furthermore, ligninsulfonic acid is not used alone.

Although it was possible to increase the concentration to some extent by increasing the amount added,
The storage stability is poor (see Table 2), and if the solid fuel concentration is further increased, the slurry viscosity will be high.
It's more difficult to do it alone than in the weight department. Sunda CMO
(Carboxymethyl cellulose So1-IJium salt) alone was able to achieve the highest solid fuel concentration with an addition amount of about 0.1 weight (J,%), but if it was added in an amount of about 70 weight (J,%) or more, Then, the slurry viscosity suddenly rose to -, and it was not possible to make a slurry with a solid fuel concentration of 70% by weight or more using CMC alone.In addition, combinations other than the present invention 1, for example, water-soluble instead of OMC Even if polymeric polyacrylamide was used, the viscosity of the slurry increased and it was not possible to increase the solid fuel concentration.However, instead of the salt of lignin sulfonic acid, calcium salt of lignin sulfonic acid was used. Even if IrJ was used, the viscosity of the slurry increased and it was not possible to increase the concentration of IrJ.

Examples 3 to 5 Two types of dispersants, the storium salt of genin sulfonic acid listed in Table 2 and the storium salt of carboxymethyl cellulose, were used as dispersants, and the solid fuel concentration was as shown in Table 2. A coke-water slurry was produced and the storage stability of the slurry was tested by method (1). The results are shown in Table 2.

Comparative Examples 8 to 11 As a dispersant, two kinds of dispersants, a sodium salt of ligninsulfonic acid alone and a formalin condensate of sodium β-naphthalenesulfonate and a butrium salt of carboxymethyl cellulose, were used in the amounts listed in Table 2. A petroleum coke-water slurry having the same fuel concentration as shown in Table 2 was produced, and the storage stability of the slurry was tested by the method (1). result d
: Shown in Table 2.

Table 2 In Table 2, in the case of the present invention, the solid fuel-water slurry was stable even after 31] (Example 3-s), whereas in the case of the sthorium salt of lignosulfonic acid alone, 1
After 0 days, precipitation occurred (Comparative Example 9), and the combination of the formalin condensate of β-raphthalene sulfonic acid thorium salt and CMC also caused precipitation after 5 days (Comparative Examples 9 to 11).

Example 6 Dispersant and 2, lignin sulfonic acid IO + triuno,
A petroleum coke-water slurry with a slurry concentration of 69.0 parts by weight, containing 0.25% salt and 0.16% by weight carbogine methylcellulose, was tested for storage stability using method (2). Tested. The results are shown in Table 6.

\ \1, ＼８、 \、 \、 ゝゝ゛＼ \、 Table 1 -6・

Claims (2)

[Claims] (1) Solid fuel is mixed with water and a dispersant to produce solid fuel.
1. A method for producing a solid fuel-water slurry, which comprises using an alkali metal salt of lignin sulfonic acid and an alkali metal salt of boxymethyl cellulose as one dispersant. (2) The solid fuel is finely powdered petroleum coke or deashed coal, and the amount of alkali metal salt of ligninsulfonic acid used is 0.05 to 0.05 parts by weight per 100 parts by weight of the slurry.
6 parts by weight, and the amount of the alkali metal salt of carboquine methyl cellulose used is 0.0 parts per 100 parts by weight of the slurry.
The method for producing a solid fuel-water slurry according to claim 1, wherein 03=0.5 parts by weight.