CN114133966B - Method for preparing low-rank coal water slurry with good slurry property based on particle size distribution model - Google Patents

Abstract

The invention discloses a method for preparing a low-order coal-water slurry with good slurryability based on a particle size distribution model. The method steps are as follows: S1: coarsely grind the coal raw material to obtain coal powder A; S2: use the coal powder A in S1 As raw material, ball milling is carried out to obtain pulverized coal B; S3: Construct the particle size distribution model of coal-water slurry, and determine the proportion of pulverized coal A and pulverized coal B according to the particle size distribution model; Powder A and coal powder B are mixed with additives and water for slurrying to obtain high-concentration coal-water slurry; wherein the coal-water slurry contains the following raw materials in parts by weight: 60-80 parts of composite coal powder, 25-35 parts of water, and 0.1-35 parts of additives 0.2 part; the composite coal powder is composed of coal powder A and coal powder B in a ratio of 2-5:1; the additive is one or more of naphthalene-based additives, lignin-based additives, and dispersant GSH; the composite The D10 particle size of coal powder is 3-5μm, and the D50 particle size is 40-50μm. The coal-water slurry prepared by the invention has better slurry-forming properties, and the error between the adopted particle size distribution model and the measured value is smaller.

Description

Method for preparing low-order coal-water slurry with good slurryability based on particle size distribution model

technical field

The invention relates to the technical field of coal-water slurry preparation, in particular to a method for preparing low-order coal-water slurry with good slurryability based on a particle size distribution model.

Background technique

As an oil substitute fuel, coal-water slurry should have high concentration, easy flow, and good stability. For low-rank coal, although the resources are relatively rich, it has the problem of poor slurryability, and the current main particle size distribution model The application of Rosin-Rammler model, Gaudin-Schuhmann model and Alfred model to low-rank coal has large errors, and it is impossible to effectively obtain CWS with good slurrying effect.

Contents of the invention

Based on the technical problems existing in the background technology, the present invention proposes a method for preparing low-order coal-water slurry with good slurryability based on the particle size distribution model. The prepared coal-water slurry has better slurryability, and the particle size distribution model adopted The error with the measured value is smaller.

The method that the present invention proposes based on particle size distribution model prepares the low-order coal-water slurry with good slurryability, method step is as follows:

S1: Coarsely grind the coal raw material to obtain coal powder A;

S2: Using the pulverized coal A in S1 as a raw material, perform ball milling to obtain pulverized coal B;

S3: Construct the particle size distribution model of the coal-water slurry, and determine the ratio of pulverized coal A and pulverized coal B according to the particle size distribution model;

S4: Mix the pulverized coal A and pulverized coal B with additives and water in the ratio determined in S3 to make slurry to obtain a high-concentration coal-water slurry.

Preferably, the coal raw material in S1 is low-rank coal.

Preferably, the low-rank coal is Shenmu coal.

Preferably, the D50 particle size of the coarsely ground coal powder A in S1 is 64-84 μm.

Preferably, the rotating speed of ball milling in S2 is 150-200r/min, and the time of ball milling is 20-40min.

Preferably, the D50 particle size of the pulverized coal B after ball milling in S2 is 5-15 μm.

Preferably, the particle size distribution model in the S3 is:

In the formula: x is a certain particle size; y is the particle content smaller than the particle size; K is the particle size when the particle content is K% (K takes the value of 0, 10, 20...80, 90); n is the model parameter ; (K+10)%>x>K%.

Preferably, the coal water slurry in the S4 comprises the following raw materials in parts by weight:

60-80 parts of composite coal powder, 25-35 parts of water, 0.1-0.2 parts of additives;

The composite pulverized coal is composed of pulverized coal A and pulverized coal B in a ratio of 2-5:1.

Preferably, the additive is one or more of naphthalene-based additives, lignin-based additives, and dispersant GSH.

Preferably, the D10 particle size of the composite coal powder is 3-5 μm, and the D50 particle size is 40-50 μm.

Beneficial technical effect of the present invention:

(1) The present invention adjusts the proportioning of pulverized coal A and pulverized coal B by building the particle size distribution model of coal-water slurry, when the particle diameter of D10 of composite pulverized coal is 3-5 μ m, when the particle diameter of D50 is 40-50 μ m, The obtained coal water slurry has the best slurrying property.

(2) Compared with the existing Rosin-Rammler model, Gaudin-Schuhmann model and Alfred model, the coal-water slurry particle size distribution model constructed by the present invention is closer to the measured value, and the error is smaller, so that it can be accurately obtained at a low The particle size distribution of high-concentration coal-water slurry prepared from rank coal with good slurryability.

Description of drawings

Fig. 1 adopts the distribution diagram of the particle size distribution model that the present invention proposes;

Figure 2 is a distribution diagram using the Rosin-Rammler model;

Figure 3 is a distribution diagram using the Gaudin-Schuhmann model;

Fig. 4 is a distribution diagram using the Alfred model;

Detailed ways

Among the present invention, the equipment used for coarse grinding is SF-high-speed pulverizer (rod mill), and the equipment used for ball milling is a vertical square planetary ball mill.

In the present invention, the coal powder particle size is measured by a BT-2003 laser particle size analyzer.

The viscosity of coal water slurry was measured by NXS-4C coal water slurry viscometer.

Example 1

The method steps of preparing the low-rank coal-water slurry with good slurryability based on the particle size distribution model proposed by the present invention are as follows:

S1: Coarsely grind the coal raw material to obtain coal powder A;

S2: Using the pulverized coal A in S1 as a raw material, perform ball milling to obtain pulverized coal B;

S3: Construct the particle size distribution model of the coal-water slurry, and determine the ratio of pulverized coal A and pulverized coal B according to the particle size distribution model;

S4: Mix the pulverized coal A and pulverized coal B with additives and water in the ratio determined in S3 to make slurry to obtain a high-concentration coal-water slurry.

The coal raw material in S1 is low-rank Shenmu coal.

The D50 particle size of coarsely ground coal powder A in S1 is 79.02 μm.

The rotation speed of the ball mill in S2 is 150r/min, and the time of the ball mill is 30min.

The D50 particle size of pulverized coal B after ball milling in S2 is 13.58 μm.

The particle size distribution model in S3 is:

In the formula: x is a certain particle size; y is the particle content smaller than the particle size; K is the particle size when the particle content is K% (K takes the value of 0, 10, 20...80, 90); n is the model parameter ; (K+10)%>x>K%.

The coal-water slurry in S4 contains the following raw materials in parts by weight: 70 parts of composite coal powder, 30 parts of water, and 0.15 parts of additive; wherein the composite coal powder is composed of coal powder A and coal powder B at a ratio of 4:1.

Additive is dispersant GSH

The D10 particle size of the composite coal powder is 4.052 μm, and the D50 particle size is 47.36 μm.

The highest slurry concentration of the coal-water slurry prepared by the above method is 63%, and the apparent viscosity is 1188.8mPa·s.

Example 2

The method steps of preparing the low-rank coal-water slurry with good slurryability based on the particle size distribution model proposed by the present invention are as follows:

S1: Coarsely grind the coal raw material to obtain coal powder A;

S2: Using the pulverized coal A in S1 as a raw material, perform ball milling to obtain pulverized coal B;

S3: Construct the particle size distribution model of the coal-water slurry, and determine the ratio of pulverized coal A and pulverized coal B according to the particle size distribution model;

S4: Mix the pulverized coal A and pulverized coal B with additives and water in the ratio determined in S3 to make slurry to obtain a high-concentration coal-water slurry.

The coal raw material in S1 is low-rank Shenmu coal.

The D50 particle size of coarsely ground coal powder A in S1 is 79.02 μm.

The rotational speed of the ball mill in S2 is 200r/min, and the time of the ball mill is 30min.

The D50 particle size of pulverized coal B after ball milling in S2 is 8.727 μm.

The particle size distribution model in S3 is:

In the formula: x is a certain particle size; y is the particle content smaller than the particle size; K is the particle size when the particle content is K% (K takes the value of 0, 10, 20...80, 90); n is the model parameter ; (K+10)%>x>K%.

The coal-water slurry in S4 contains the following raw materials in parts by weight: 70 parts of composite coal powder, 30 parts of water, and 0.15 parts of additive; wherein the composite coal powder is composed of coal powder A and coal powder B at a ratio of 4:1.

The additive is a naphthalene-based additive.

The D10 particle size of the composite coal powder is 3.308 μm, and the D50 particle size is 48.24 μm.

The highest slurry concentration of the coal-water slurry prepared by the above method is 64%, and the apparent viscosity is 1305.2mPa·s.

comparative example

Taking the currently most commonly used particle size distribution models Rosin-Rammler, Gaudin-Schuhmann, and Alfred models as comparative examples, the predicted particle size distribution and the measured particle size distribution are compared with the particle size distribution model proposed by the present invention. The results are shown in Figures 1-4 shown. It can be seen from Figures 1-4 that the value proposed by the present invention is closer to the actual measured value, and the error is smaller, so that the particle size distribution of high-concentration coal-water slurry prepared with low-rank coal and good slurryability can be accurately obtained.

Claims (6)

1. prepare the method for the good low rank coal-water slurry of slurrying property based on particle size distribution model, it is characterized in that, method step is as follows: S1: Coarsely grind the coal raw material to obtain coal powder A; S2: Using the pulverized coal A in S1 as a raw material, perform ball milling to obtain pulverized coal B; S3: Construct the particle size distribution model of the coal-water slurry, and determine the ratio of pulverized coal A and pulverized coal B according to the particle size distribution model; S4: Mix the pulverized coal A and pulverized coal B with additives and water in the ratio determined in S3 to make slurry to obtain high-concentration coal-water slurry; The D50 particle size of coarsely ground coal powder A in S1 is 64-84 μm; The rotating speed during ball milling in S2 is 150-200r/min, and the time of ball milling is 20-40min; The D50 particle size of pulverized coal B after ball milling in S2 is 5-15 μm; The particle size distribution model in S3 is:

In the formula: x is a certain particle size; y is the particle content smaller than the particle size; K is the particle size when the particle content is K%, and the value of K is 0, 10, 20...80, 90; n is the model parameter; (K+10)%>x>K%. 2. The method for preparing a low-rank coal-water slurry with good slurry properties based on a particle size distribution model according to claim 1, wherein the coal raw material in the S1 is low-rank coal. 3. The method for preparing a low-rank coal-water slurry based on a particle size distribution model according to claim 2, wherein the low-rank coal is Shenmu coal. 4. the method for preparing the good low-order coal-water slurry based on particle size distribution model according to claim 1, is characterized in that, the coal-water slurry in the described S4 comprises the raw material of following parts by weight: 60-80 parts of composite coal powder, 25-35 parts of water, 0.1-0.2 parts of additives; Wherein the composite pulverized coal is composed of pulverized coal A and pulverized coal B in a ratio of 2-5:1. 5. according to claim 4, based on particle size distribution model, prepare the method for low-order coal-water slurry with good slurry property, it is characterized in that, described additive is naphthalene series additive, lignin series additive, dispersant GSH one or several. 6. the method for preparing the low-order coal-water slurry with good slurry properties based on the particle size distribution model according to claim 4, characterized in that, the D10 particle diameter of the composite pulverized coal is 3-5 μm, D50 particle diameter 40-50μm.

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