CN1021343C - Solid fuel-water slurry composition and process for preparation of same - Google Patents

Abstract

A solid fuel-water slurry composition containing a relatively large amount of solid fuel particles but having a relatively low viscosity. It contains 50-80% by weight of coal and/or petroleum solid fuel particles, and 0.01-3% by weight of dispersant and, if necessary, 0.01-0.5% by weight of stabilizer. The geometric mean diameter (Dp50) of the particles is not greater than 74 μm, and the size distribution of these particles is adjusted to the following state: the arithmetic mean of the upper geometric standard deviation (σg+) and the lower geometric standard deviation (σg-) is in logarithm The normal distribution is in the range of 6-12, and the ratio (σg+/σg-) is not greater than 0.6. and methods of making such slurry compositions.

Description

The present invention relates to a solid fuel-water slurry composition. More specifically, the present invention relates to a solid fuel-water slurry composition having a high solids content but a low viscosity which is easy to transport, store and handle, and is also associated with the preparation of such a slurry related to the method of the thing.

Recently, solid fuels such as coal and petroleum coke have been re-emphasized as energy alternatives to petroleum. However, compared with liquid fuels such as petroleum, solid fuels have the disadvantage of being difficult to transport and store. In addition, the work efficiency of loading and unloading solid fuel is not high.

To overcome these disadvantages, solid fuel-water slurries obtained by dispersing finely ground solid fuel in water have recently been developed. However, such solid fuel-water slurries still have the disadvantage that increasing the solid fuel content of the slurry causes a significant increase in the viscosity of the resulting slurry. The poor flowability of solid fuel-water slurries with increased viscosity makes them difficult to handle and transport through pipelines. Reducing the solid fuel content of the slurry reduces the viscosity of the solid fuel-water slurry. However, the transport efficiency of such solid fuel-water slurries with reduced solid fuel content is also reduced. Another disadvantage of reduced solid fuel content is that it must be pre-dehydrated before it can be used as a fuel or gasification source.

In order to avoid the above disadvantages, various schemes have been proposed, such as adding a dispersant, or adjusting the particle size distribution.

However, it has been found that the solid fuel particles of solid fuel-water slurries having a high solid fuel content and whose viscosity has been reduced according to known methods tend to settle during long-term storage or transport on tankers or tankers, and these settled particles Clumping occurs during dehydration, forming a compacted mass. When used as a solid fuel-water slurry, these compacted chunks are difficult to redisperse. Therefore, for the stabilization of solid fuel-water slurries, further improvements to the method are required. step improvement.

It has also been found that the known methods based on adjusting the particle size distribution have a further disadvantage. Japanese Patent Provisional Publication No.59(1984)-15486 describes a method of increasing the geometric standard deviation (σg) by adjusting the particle size distribution to obtain a solid fuel-water slurry with high solid fuel content and low viscosity. In this method, the geometric standard deviation is increased by expanding the range of the particle size distribution. The widening of the particle size distribution is achieved by increasing the large particle content and/or the very fine particle content. The increase in the content of large particles will reduce the stability of the slurry in storage and transportation, and cause undesired troubles, such as blocking the burner during the injection process, increasing non-combustible particles during the combustion process, etc. In addition, it is actually quite difficult to increase the ultrafine particle content without consuming a large amount of grinding energy. Furthermore, the increase in the content of ultrafine particles will inevitably lead to a significant increase in the specific surface area of the particles, which requires an increase in the consumption of dispersants.

One of the objects of the present invention is to provide a solid fuel-water slurry composition having a high content of solid fuel particles and a low viscosity.

Another object of the present invention is to provide a solid fuel-water slurry composition with high solid fuel particle content and low viscosity, which is extremely stable, and the solid fuel particles can remain in a good dispersion state in the water slurry. When the slurry is stored for a long time or transported under harsh conditions, it will basically not produce compacted sediment.

A third object of the present invention is to provide a suitable method for preparing the above improved solid fuel-water slurry.

The present invention provides a solid fuel-water slurry composition, which contains 50-80% by weight of solid fuel particles of coal and/or petroleum coke, wherein the geometric mean diameter (Dp50) of the particles is not more than 74 μm, which The particle size distribution is adjusted so that the arithmetic mean of its upper geometric standard deviation (σg+) and lower geometric standard deviation (σg-) is in the range 6-12 in a lognormal distribution, and its ratio σg+/ σg-, not greater than 0.6.

The terms "geometric mean diameter" and "geometric standard deviation" as used herein are terms commonly used in defining particle size and its distribution. Specifically, these terms are defined in terms of diameter and weight percent cumulative passage in a lognormal distribution in the following manner:

Geometric mean diameter (Dp50): The diameter at which the cumulative passing weight percentage is equivalent to 50%.

Upper geometric standard deviation (σg+): the ratio of the diameter (Dp+σ) when the cumulative passing weight percentage is equivalent to 84.13%, and the geometric mean diameter (Dp50), that is, (Dp+σ)/Dp50.

Lower geometric standard deviation (σg-): the ratio of the geometric mean diameter (Dp50) to the diameter (Dp-σ) when the cumulative passing weight percentage is equivalent to 15.87%, that is, Dp50/(Dp-σ).

Geometric standard deviation (σg): The arithmetic mean of the upper and lower geometric standard deviations (in the lognormal distribution), that is, (σg+tenσg-)/2.

The above-mentioned solid fuel-water slurry composition can be suitably prepared by the following method, which method comprises:

In a first step, grinding a solid fuel containing wet coal or petroleum coke particles having a geometric mean diameter not greater than about 20 mm in water or an aqueous solution of additives to produce a solid fuel having a geometric mean diameter (Dp50 ¹ ) between 30 and 149 μm Granular solid fuel - water slurry;

In the second step, the solid fuel-water slurry prepared in the first step is mixed with the coarse coal or petroleum coke mentioned above, and water or an aqueous solution of additives, and the resulting mixture is wet-milled with a rod mill , to prepare a solid fuel-water slurry containing solid fuel particles whose geometric mean diameter (Dp50 ² ) is not greater than 74 μm, and which is the same as the geometric mean diameter of the solid fuel particles in the solid fuel-water slurry obtained in the first step (Dp50 ¹ ) ratio Rs (= Dp50 ¹ /Dp50 ² ) is between 0.8 and 4; Rw (= F1/F2) is between 0.4 and 2.4, where F1 represents the ratio of solid fuel added to the first step Feed rate (weight), F2 represents the feed rate (weight) of the coarse grained solid fuel added in the second step;

And Rs/Rw is between 1 and 3.

The present invention also provides a solid fuel-water slurry composition, which contains 50 to 80 parts by weight of solid fuel particles of coal and/or petroleum coke and 0.01-0.5 Parts (by weight) of stabilizer (i.e. stabilizer composition). The stabilizer consists of 1-20% by weight of at least one water-soluble polymer and 80-99% by weight of fine particles of at least one inorganic substance. The water-soluble polymer used is selected from natural gum, modified natural gum, polyhexenol, polyacrylamide, carboxymethyl cellulose, hydroxyethyl cellulose and the like. The inorganic substances used are selected from bentonite, palygorskite, sepiolite, chrysotile and the like.

The flow chart shown in Figure 1 can be used to prepare the solid fuel-water slurry of the present invention.

The solid fuel used in the present invention is coal and/or petroleum coke. Coal and petroleum coke are not particularly limited, and most of commonly used coal and petroleum coke are suitable. It is preferred to use coal with an ash content of about 6% by weight. Coals containing about 10% by weight ash also work well after deashing, such as by dense media enrichment, to ash levels below about 6% by weight. Petroleum coke can be a by-product of the petroleum refining process and may contain 0.1% to 1% ash by weight.

The solid fuel-water slurry composition of the present invention contains 50-80% by weight of solid fuel particles, preferably 65-75%. The geometric mean diameter (Dp50) of the particles is not more than 74 µm, preferably 20-53 µm. If the geometric mean diameter is 74 µm or more, the content of coarse particles increases, causing various problems in the operation using the slurry. If the geometric mean diameter is too small, the content of extremely fine particles increases. From the viewpoint of production efficiency, it is disadvantageous to produce a solid fuel containing an increased amount of fine particles. Furthermore, in order to disperse solid fuel containing a large amount of ultrafine particles, it is also necessary to increase the amount of dispersant.

As for the solid fuel used in the slurry of the present invention, its particle size distribution is adjusted to the following state: the arithmetic mean (σg ⁺ +σg-)/2 of the upper and lower geometric standard deviations in the lognormal distribution is at 6- between 12; the ratio of upper and lower standard deviation σg+/σg- is not greater than 0.6, preferably not greater than 0.4. By adjusting the particle size distribution in this way, it is possible to produce solid fuel-water slurries with increased solid fuel content but reduced viscosity values.

If you want to reduce the content of coarse particles under the condition that σg+/σg- is 0.6 or greater, you must reduce the geometric mean diameter (Dp50). This makes the industrial production of solid fuel-water slurries with high solid fuel content and low viscosity values difficult.

A solid fuel-water slurry composition containing an adjusted particle size distribution according to the present invention may be conveniently prepared by a process comprising the following steps:

(1) The first step

A solid fuel consisting of coarse particles of coal or petroleum coke having a geometric mean diameter not greater than about 20 mm is wet ground in water or an aqueous solution of additives to produce a solid fuel having a geometric mean diameter (Dp50) between 30 and 149 μm (preferably A solid fuel-water slurry of solid fuel particles between 44-149 μm). The resulting slurry preferably has a solid fuel particle content of 30-80% by weight, more preferably 50-70% by weight. Wet-operated mills can be customary mills such as ball mills, tube mills or mill mills. Examples of additives include the aforementioned dispersants, stabilizers, and pH regulators such as sodium hydroxide, potassium hydroxide, and ammonium hydroxide.

(2) The second step

The solid fuel-water slurry prepared in the first step is mixed with the aforementioned coal or petroleum coke coarse particles, and the aqueous solution of water or additives, and is ground with a known grinder (preferably a rod mill) The resulting mixture is subjected to wet milling to prepare a solid fuel-water slurry whose solid fuel particles have a geometric mean diameter (Dp50 ² ) not greater than 74 μm, preferably between 20 and 53 μm, and which are identical to those prepared in the first step. The geometric mean diameter (Dp50 ¹ ) of the solid fuel particles of the obtained solid fuel-water slurry has the following relationship: Rs = Dp50 ¹ /Dp50 ² = 0.8-4, preferably between 0.8-3.

As mentioned earlier, for the grinding step in the second step, it is most suitable to use a rod mill, because the desired solid fuel-water slurry can be obtained in a short grinding operation cycle by using a rod mill liquid.

In above-mentioned method, Rw=F1/F2 is preferably between 0.4-2.4, is better between 0.6-1.6, and wherein F1 is the feed rate (weight) of the coarse solid fuel that adds in the first step F2 is Feed rate (weight) of coarse solid fuel directly added in the second step. Secondly, Rs/Rw is preferably between 1-3. Finally, the geometric standard deviation (σg) in the log-normal distribution of the solid fuel particles in the solid fuel-water slurry obtained in the second step is preferably between 3.5-12, more preferably between 6-12 .

The above-mentioned method consisting of two grindings will be described in detail below with reference to the flow chart shown in FIG. 1 .

first step

Add water to the mixing tank 1 through the pipeline 15, or add additives (such as dispersant) and/or pH regulator, and then send it to the wet mill through the pipeline 16, pump 2, pipeline 17, flow meter 3 and pipeline 18 6. Coarse solid fuel is supplied to the wet mill through pipeline 19, hopper 13, pipeline 20, constant feeder 4, pipeline 21, crusher 5 (if necessary, it can be installed to break up large pieces in the feed) and pipeline 22 Machine 6. The amount of water and solid fuel particles supplied to the wet mill 6 is controlled so that the resulting solid fuel-water slurry has a solid particle content of between 30-80% by weight.

In wet mill 6, solid fuel particles and water (including optional additives) are mixed and simultaneously comminuted to produce a solid fuel-water slurry containing particles having a geometric mean diameter in the range of 30-149 microns. A portion of this solid fuel-water slurry can be circulated through line 23 , pump 7 , lines 24 and 25 , back to wet mill 6 .

second step

Through pipeline 23, pump 7, pipeline 24, pipeline 26, flow meter 8 and pipeline 27, the solid fuel-water slurry prepared in the first step is sent to the grinder 11 (eg rod mill). Through pipeline 28, hopper 14, pipeline 29, constant feeder 9, pipeline 30, crusher 10 (fuel particles granules are comminuted) and line 31, the solid fuel particles are fed to the grinder 11. Water and optional additives (such as the aforementioned reagents) are sent via line 38 to mixing tank 50 and then to mill 11 via line 39, pump 44, line 40, flow meter 51 and line 41. A fine grinding process is carried out in the grinder 11 to prepare a solid fuel-water slurry with the desired particle size distribution.

The solid fuel-water slurry prepared in the grinder 11 is led to the slurry storage tank 12 through line 32 and can be discharged through line 33 , pump 43 , and lines 34 and 35 . Stabilizers can be added to the discharged slurry if desired. A portion of the solid fuel-water slurry may be recycled through line 36 to return to the mill 11 and/or through line 37 to return to the wet mill 6 .

As mentioned above, in order to suppress the increase in viscosity which seems to be caused by the increase in the concentration of solid fuel, the solid fuel-water slurry composition of the present invention may contain suitable additives such as dispersants. As the dispersant, a known dispersant can be used. Examples of dispersants include naphthalenesulfonic acid and its salts, petroleum sulfonic acid and its salts, lignosulfonic acid and its salts, and their formaldehyde condensation products; polyethylene oxide-alkyl ether sulfate and its salts ; polyoxyethylene alkyl aryl ether sulfate and its salts; polyglycerol sulfate; melamine resin sulfonic acid and its salts; and coal extraction sulfonic acid and its salts.

The amount of the dispersant used is preferably 0.01 to 3 parts by weight per 100 parts by weight of the solid fuel-water slurry. Dispersants may be added to the solid fuel-water slurry at any step in the slurry preparation process. Otherwise, the dispersant can also be added to the previously prepared solid fuel-water slurry.

The solid fuel-water slurry composition of the present invention may also contain suitable additives, such as pH adjusters. As the pH adjuster, known pH adjusters can be used. Examples of pH adjusters are sodium hydroxide, potassium hydroxide, and ammonium hydroxide.

The solid fuel-water slurry composition of the present invention has a lower viscosity, such as about 800mPa·s or less (the determination of the viscosity is described later), but it contains not less than 70% by weight of solid fuel.

The solid fuel-water slurry composition of the present invention. It can be expressed as a slurry with the following composition: every 100 parts (weight) of solid fuel-water slurry contains 50-80 parts (weight) of coal and/or petroleum coke solid fuel particles, 0.01-0.5 parts (weight) (preferably 0.02-0.3 part) stabilizer. The stabilizer contains 1-20% by weight of at least one water-soluble polymer and 80-99% by weight (preferably 90-98%) of fine particles of at least one inorganic substance. The water-soluble polymer can be selected from natural gums, modified natural gums, polyvinyl alcohol, polyacrylamide, carboxymethylcellulose and hydroxyethylcellulose. Fine particles of inorganic substances can be selected from bentonite, palygorskite, sepiolite and chrysotile.

The solid fuel-water slurry composition of the present invention containing the above-mentioned stabilizer consisting of a specific organic substance and a specific inorganic substance has greatly improved stability during storage and transportation thereof.

Among the above-mentioned water-soluble polymers, the natural gum is preferably guar gum, xanthan gum (xanthane gum), locust bean gum, karaya gum, sodium alginate or a modified product of the above-mentioned natural gum.

In order to stabilize the slurry composition, a stabilizer may be incorporated into the solid fuel slurry composition which does not have the previously specified particle size distribution.

The invention will be further illustrated by the following examples.

The method for measuring the particle size distribution of the solid fuel and the method for measuring the viscosity of the solid fuel-water slurry adopted in the following examples are stated below:

(1) Method for determining particle size distribution of solid fuel

The measurement was performed with a centrifugal particle size analyzer (manufactured by Shimazu Seisakusho Co., Ltd., Japan) and a standard sieve.

(2) Method for measuring the viscosity of solid fuel-water slurry

Using a Brookfield rotational viscometer (Tokyo Keiki Co., Ltd., Japan) made, using drum No. 3) for viscosity measurements on freshly prepared solid fuel-water slurries. The measurement is carried out at 27C, the rotation speed is 12r.p.m., and the measurement value is taken 1 minute after the start of the measurement procedure.

Example 1

According to the flowchart of Fig. 1, a solid fuel-water slurry was prepared using a ball mill as the wet mill 6 in the first step.

Solid fuel (coarsely crushed coal having a geometric mean diameter of about 8 mm) was continuously fed to the ball mill 6 through line 22, while an aqueous dispersant solution (formaldehyde condensate containing sodium β-naphthylsulfonate) was continuously fed through line 18 thereto. In the ball mill 6, the coarsely crushed coal was ground in a dispersant solution to produce a solid fuel-water slurry having a solid particle geometric mean diameter (Dp50 ¹ ) of 53.4 μm.

This solid fuel-water slurry is then fed continuously to the pin mill 11 via line 27 - the second step. At the same time, another part of the coarsely crushed coal and another part of the dispersant solution are supplied to the pin mill 11 through lines 31 and 41, respectively. In the rod mill 11, the supplied solid fuel was finely ground to prepare a solid fuel-water slurry whose characteristic values are shown in Table 1. Finally the slurry thus produced is discharged continuously through line 35.

Reference Examples 1 and 2

The procedure of Example 1 was repeated, using the same equipment but changing the grinding conditions, to prepare solid fuel-water slurries containing the particle diameter distribution values listed in Table 1, which were outside the range specified by the present invention. The property values of the resulting slurry are also listed in Table 1.

From the results listed in Table 1, it is evident that the solid fuel-water slurry containing solid fuel particles prepared according to the present invention with particle diameter distribution values within the specified range, and containing almost the same amount of solid fuel particles, but the particles Solid fuel-water slurries having diameter distribution values outside the range specified by the present invention have considerably lower viscosity values.

Table 1

Example 1 Reference Example 1 Reference Example 2

Q[kg/hm ² ] 325 311 256

Rw 0.90 0.95 0.34

R5 1.21 0.79 1.44

Rs/Rw 1.34 0.85 4.31

final slurry product

Dp50 ² 44.1 27.4 31.6

50 mesh pass rate [%] 99.8 99.9 99.9

σg 6.1 5.1 5.5

Serum concentration [%, weight] 70.1 69.5 69.9

Viscosity [mPa·s] 730 1200 1150

Note: Q: The rate of the material to be ground into the rod mill (the weight of the material added per unit effective area)

Rw: F1/F2, that is, the weight ratio of the coarsely crushed solid fuel added in the first step to the weight of the coarsely crushed solid fuel added in the second step Rs: Dp50 ¹ /Dp50 ² , that is, in the first or The ratio of the geometric mean diameters of the solid fuel particles in the solid fuel-water slurries respectively prepared in the second step.

Example 2

Deashed coal having the following composition and properties was wet ground in a ball mill and then classified to remove particles larger than No. 50 mesh to obtain various samples containing particles of different sizes. The obtained geometric mean diameters Dp50, Dp+σ and Dp-σ of each sample are listed in Table 2.

Analytical data of deashed coal

Component analysis (%, weight): Moisture 5.1

(JIS M8813)

Gray 2.3

Volatile matter 40.8

Fixed carbon 51.8

Calorific value (Kcal/Kg, JIS M8814): 7410

Elemental analysis (%, weight): Carbon 79.6

(JIS M8813)

Hydrogen 5.2

Nitrogen 1.7

Sulfur 0.5

Oxygen 10.6

Gray 2.4

Table 2

Sample Dp50 Dp+σ Dp-σ

A 40μm 90μm 7.9μm

B 57μm 120μm 17μm

C 26μm 79μm 2.9μm

D 2.8μm 9.7μm -

64 parts by weight of Sample A, 28 parts by weight of Sample C and 8 parts by weight of Sample D were homogeneously mixed to prepare a particle mixture of coal having the geometric mean diameter and particle size distribution listed in Table 3 .

70 parts (weight) of the above-mentioned pulverized coal mixture, 29.5 parts (weight) of water and 0.5 parts (weight) of a dispersant (β-naphthalenesulfonic acid formaldehyde condensate, sodium salt) are put into a mixing tank, and stirred by hand at room temperature. The mixture thus obtained was stirred with a laboratory stirrer (Labo disper) (made by Tokushu Kiko Kogyo Co., Ltd., Japan) at 3000 r.p.m. for 3 minutes to prepare a solid fuel containing 70% by weight of fuel particles- water slurry.

The measured viscosities are listed in Table 3.

Example 3

In the same manner as in Example 2, but the pulverized coal mixture is mixed with 72 parts (by weight) of sample B. 21 parts (by weight) of sample C and 7 parts (by weight) of sample D, a Solid Fuel-Water Slurry.

The geometric mean diameter and particle size distribution of the solid fuel-water slurry obtained are listed in 3. The measured viscosity is also tabulated in 3.

Reference Examples 3 and 4

In the same manner as in Example 2, but using pulverized coal whose geometric mean diameter and particle size distribution are not within the specified range of the present invention, a solid fuel-water slurry was prepared. The geometric mean diameter and particle size distribution of the obtained solid fuel-water slurry, as well as the measured viscosity, are listed in Table 3.

table 3

Sample Arithmetic Mean Ratio Geometric Mean Diameter Dp+σ Viscosity

[μm] [μm] [mPa s]

Example 2 6.2 0.25 32 80 780

Example 3 6.1 0.26 44 110 700

Reference Example 3 6.1 0.71 16 84 2700

Reference Example 4 6.0 0.71 22 110 1300

Note: The arithmetic mean is the arithmetic mean of the upper and lower geometric standard deviations,

That is (σg ⁺ +σg-)/2

The ratio is the ratio of σg+ to σg-, that is, σg+/σg-

The geometric mean is Dp50[μm]

Example 4-6

In the same manner as in Example 2, a coal particle mixture having the same geometric mean diameter and particle size distribution as in Example 2 was prepared, but the coal particle mixture was prepared from deashed coal having the following composition:

Analytical data of deashed coal:

Component analysis (% weight): Moisture 5.3

(JIS M8812) Ash 0.7

Volatile matter 38.8

Fixed carbon 55.2

The coal particle mixture, water, dispersant (formaldehyde condensate of β-naphthalenesulfonic acid, sodium salt) and pH regulator (ammonium hydroxide) were placed in a mixing tank at room temperature, and then mixed well by hand. 0.5 parts by weight of dispersant per 100 parts by weight of solid fuel-water slurry. Practical The resulting mixture was stirred for 3 minutes with a laboratory stirrer at 3000 r.p.m: to prepare an initial solid fuel-water slurry containing 70% by weight of fuel particles and having a viscosity of 800 mPa·s and a pH of 8.0.

The stabilizer was then added to the nascent solid fuel-water slurry and the slurry was hand agitated. The slurry was then stirred at 3000 r.p.m. for 3 minutes using the above-mentioned laboratory stirrer to obtain a solid fuel-water slurry with a viscosity of about 1000 mPa·s.

Reference Examples 5-10

Repeat the procedure of Example 4, but replace the stabilizer with a single compound in Reference Examples 5-9, and replace the stabilizer with a mixture whose composition exceeds the present invention in Reference Example 10, to obtain a viscosity of about 1000mPa·s solid fuel-water slurry.

Evaluation of Storage Stability and Transport Stability

With respect to the solid fuel-water slurries obtained in Examples 4-6 and Reference Examples 5-10, the storage stability and transportation stability thereof were evaluated in the following manner.

Method for determining storage stability:

The solid fuel-water slurry was placed in a 100 ml glass test tube, which was then left standing for 7 days. At the end of the 7-day storage period, a glass rod was inserted into the slurry to determine whether fuel particles had settled at the bottom of the test tube, or whether a lump had formed at the bottom of the test tube.

The measurement results are represented by the following symbols:

AA: No deposited particles and no agglomerated particles were observed;

BB: Sedimentary particles were observed, but the formation of agglomerated particles was not observed;

CC: Formation of agglomerated particles was observed.

Method for determining transport stability:

The solid fuel-water slurry was placed in a 100ml glass test tube, which was then subjected to transverse vibration (amplitude 40mm, frequency 90min ^-1 ) for 5 hours. At the end of the vibration, a glass rod was inserted into the slurry to determine whether the fuel particles had settled at the bottom of the test tube, or formed agglomerates of particles at the bottom of the test tube.

The measurement results are represented by the following symbols:

aa: neither particle deposition nor agglomeration was found;

bb: Particle deposition was found, but no agglomeration was found;

cc: Formation of particle agglomerates was found.

The results are listed in Table 4.

Table 4

Stabilizer Stabilizer Addition Amount Storage Stability Transport Stability

(weight ratio) (%, weight)

Example 4 xanthan gum (6) 0.106 AA aa

Palygorskite (94)

Example 5 Polyvinyl alcohol (5) 0.084 AA aa

Bentonite (95)

Example 6 Hydroxyethylcellulose (5) 0.100 AA aa

Bentonite (95)

Reference Example 5 Xanthan Gum (100) 0.006 CC bb

Reference Example 6 Polyvinyl alcohol (100) 0.004 CC bb

Reference Example 7 Hydroxyethylcellulose (100) 0.005 CC bb

Reference Example 8 Palygorskite (100) 0.130 AA cc

Reference Example 9 Bentonite (100) 0.135 BB cc

Reference Example 10 Polyvinyl alcohol (22) 0.018 BB bb

Bentonite (78)

Note: The amount of additives to be added depends on the amount of solid fuel-water slurry.

Claims (15)

1. A solid fuel-water slurry composition containing 50-80% by weight of solid fuel particles of coal and/or petroleum coke and 0.01-3% by weight of a dispersant, wherein the geometric mean diameter of the particles (Dp50) is not greater than 74 μm, and the particle size distribution is adjusted so that the arithmetic mean of the upper geometric standard deviation (σg+) and the lower geometric standard deviation (σg-) in the lognormal distribution is between 6-12, and Their ratio (σg+/σg-) is not more than 0.6. 2. The solid fuel-water slurry composition according to claim 1, wherein it contains 65-75% by weight of solid coal and/or petroleum coke as a solid fuel. 3. A solid fuel-water slurry composition according to claim 1, wherein the solid fuel particles have a geometric mean diameter (Dp50) in the range of 20-53 µm. 4. The solid fuel-water slurry composition according to claim 1, wherein the ratio (σg+/σg-) of the upper and lower geometric standard deviations is not more than 0.4. 5. The solid fuel-water slurry composition according to claim 1, wherein the dispersant is selected from the group consisting of naphthalenesulfonic acid and its salts, petroleum sulfonic acid and its salts, ligninsulfonic acid and its salts, and Their formaldehyde condensates, polyoxyethylene alkyl ether sulfates and their salts, polyoxyethylene alkylaryl ether sulfates and their salts; polyglycerol sulfates, melamine resin sulfonic acids and their salts, and Coal distillate sulfonic acid and its salts. 6. The solid fuel-water slurry composition according to claim 1, which consists of 100 parts by weight of solid fuel-water slurry containing 50-80% by weight of coal or/and petroleum coke solid fuel particles, 0.01-3 parts by weight of dispersant, And the composition of 0.01-0.5 parts by weight of stabilizer, containing 1-20% by weight of at least one water-soluble polymer selected from the following materials in the stabilizer: natural gum, modified natural gum, polyvinyl alcohol, polyacrylamide, Carboxymethyl fiber and hydroxyethyl cellulose also contain 80-99% by weight of fine particles of at least one inorganic substance selected from bentonite, palygorskite, sepiolite and chrysotile. 7. A solid fuel-water slurry composition, which consists of 100 parts by weight of a solid fuel-water slurry containing 50-80% by weight of coal and/or petroleum coke solid fuel particles, 0.01-3 parts by weight of a dispersant, and a stabilizer Composed of 0.01-0.5 parts by weight, the stabilizer contains 1-20% by weight of natural gum, modified natural gum, polyvinyl alcohol, polyacrylamide, carboxymethyl cellulose and hydroxyethyl cellulose The at least one water-soluble polymer also contains 80-99% by weight of fine particles of at least one inorganic substance selected from bentonite, palygorskite, sepiolite and chrysotile. 8. The solid fuel-water slurry composition according to claim 7, characterized in that the water-soluble polymer is a natural gum selected from the group consisting of guar gum, xanthan gum, locust bean gum, karaya gum, sodium alginate and A modified product of the natural gum. 9. A solid fuel-water slurry composition according to claim 7, wherein the stabilizer comprises 2-10% by weight of a water-soluble polymer and 90-98% by weight of fine particles of inorganic substances. 10. The solid fuel-water slurry composition according to claim 7, wherein the stabilizer is contained in an amount of 0.02-0.3 parts by weight per 100 parts by weight of the solid fuel-water slurry. 11. A solid fuel-water slurry composition according to claim 7, characterized in that it contains 65-75% by weight of solid fuel. 12. The solid fuel-water slurry composition according to claim 7, wherein the dispersant is selected from naphthalenesulfonic acid and its salts, petroleum sulfonic acid and its salts, ligninsulfonic acid and its salts, and their formaldehyde condensation products, polyoxyethylene alkyl ether sulfuric acid and its salts, polyoxyethylene alkylaryl ether sulfuric acid and its salts, polyglycerol sulfate, melamine resin sulfonic acid and its salts; and coal distillate Sulfonic acids and their salts. 13. A method of preparing a solid fuel-water slurry composition, the method comprising: The first step is to grind coal or petroleum coke particle solid fuel with a geometric mean diameter not greater than 20mm in a wet state in water or an aqueous additive solution to prepare solid fuel particles with a geometric mean diameter (Dp50 ¹ ) between 30-140μm A water slurry of solid fuel, In the second step, the solid fuel-water slurry prepared in the first step is mixed with water or an added aqueous solution, and the above-mentioned coarse coal or petroleum coke, and the resulting mixture is ground with a rod mill to prepare a solid fuel For the one-water slurry, the geometric mean diameter (Dp50 ² ) of the solid fuel particles is not greater than 74 μm, and has the following relationship with the geometric mean diameter (Dp50 ¹ ) of the solid fuel-water slurry prepared in the first step: R _S ＝Dp50 ¹ /Dp50 ² ＝0.80～4, Rw＝F1/F2＝0.4～2.4, wherein F1, F2 are the feeding rate (weight) of the coarse solid fuel added to the first step and the second step respectively , and Rs/Rw=1-3. 14. A method according to claim 13, characterized in that the first step is carried out to produce a solid fuel-water slurry having a solid fuel particle geometric mean diameter (Dp50 ¹ ) between 44 and 149 µm. 15. A method according to claim 13, characterized in that a second step is carried out to produce a solid fuel-water slurry having an Rs value between 0.8 and 3.

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