JPS62230888A - Production of highly concentrated coal-water slurry - Google Patents

Abstract

PURPOSE:To obtain the titled slurry as a valuable fuel irrespective of coal type, by grinding/mixing treatment, using wet mills, of coal and water to regulate their feeds followed by regulation of the coal particle size, viscosity and coal concentration of the resulting coal-water slurry in this order. CONSTITUTION:The objective highly concentrated coal-water slurry can be obtained by feeding coal and water from coal storage tanks 10 and a water storage tank 13, respectively, to wet mills 1, 2 and 3 to carry out grinding/ mixing treatment in such a manner that (A) the coal particle size regulation of the resulting slurry is carried out, using regulators 11, by controlling coal feeds to the respective wet mills 1, 2, and 3, and (B) the viscosity regulation and (C) coal concentration regulation of said slurry are each carried out by controlling water feeds to the respective wet mills 1, 2, and 3, the procedures (A), (B) and (C) being performed in this order corresponding to respective priorities.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for producing highly concentrated coal-water slurry, which has recently attracted attention as a fuel to replace petroleum.
Coal and water are crushed and mixed in a wet mill to produce a coal-water slurry, and the coal particle size of the produced coal-water slurry is adjusted by adjusting the amount of coal supplied to the wet mill. The present invention relates to a method for producing a high-concentration coal-water slurry in which viscosity adjustment and coal concentration adjustment are performed by adjusting the amount of water supplied to the wet processes (i) and (u).

[Conventional technology]

Conventionally, in the above-mentioned manufacturing method, the coal particle size, viscosity, and coal concentration of the produced coal-water slurry were treated and adjusted as equivalent in terms of fuel quality.

[Problem that the invention seeks to solve]

However, there is a correlation between the kings of particle size, viscosity, and concentration.
If one is adjusted by adjusting the coal supply amount or water supply amount, the other will change, and the correlation characteristics differ depending on the coal type, etc. In such cases, conventional property adjustment that treats the champion equally may result in products with low flammability, or poor pipe transportability. The burner produces substances with poor sprayability, etc.
There was a problem in that a highly concentrated coal-water slurry was produced that had serious defects as a fuel.

The purpose of the present invention is to stabilize the quality of the produced coal-water slurry as a fuel by establishing a concept for adjusting the coal particle size, viscosity, and coal concentration, which are correlated with each other. [Means for] The characteristic means of the method for producing high-concentration coal-water slurry according to the present invention is to adjust the coal particle size of the coal-water slurry produced by pulverizing and mixing coal and water using a wet mill, and to adjust the amount of coal supplied to the wet mill. In carrying out viscosity adjustment and coal concentration adjustment by adjusting the amount of water supplied to the wet mill, a ranking is established based on the importance of each property adjustment, and the ranking is determined by adjusting the coal particle size, viscosity adjustment,
The advantage is that the coal supply amount adjustment and the water supply i adjustment are carried out in the order of the coal concentration adjustment, and their functions and effects are as follows.

[For production]

In high-concentration coal-water slurry, the coal particle size is the most important requirement for whether or not it can be burned well as a fuel because it is involved in combustibility and sprayability in a burner.

In addition, viscosity is related to pipe transportability and sprayability in burners, and therefore, as a liquid fuel to replace petroleum, it is an important requirement next to the above-mentioned coal particle size in terms of supply to burners.

In that respect, the coal concentration is related to the calorific value and is not necessarily optimal, but if the combustion is good and the supply to the burner is smooth to some extent, a slight decrease in the calorific value will affect fuel quality. , fully compensated.

Therefore, if the adjustment is performed in the order of importance of coal particle size, viscosity, and coal concentration, it will not be possible to adjust the kings of coal particle size, viscosity, and coal concentration to their respective optimal states due to the correlation between the kings. Even in such a case, it is possible to produce a highly concentrated coal-water slurry whose properties are controlled to be suitable as a fuel.

〔Effect of the invention〕

As a result, it has become possible to stably produce high-concentration coal-water slurry that is highly valuable as a fuel, regardless of the υ of different coal types. The practical application of water slurry has now been promoted.

〔Example〕

Next, embodiments of the present invention will be described based on the drawings.

The drawing shows a production system for high-concentration coal-water slurry used as fuel, +1) is a rod mill for pre-pulverizing and mixing coal, water, and additives, (2) and (3)
) is a tower mill that further pulverizes and mixes the powder and crushed mixture from Rodmi/l/fl) to produce coal-water slurry.

(4) and (5) are Tawami/L/+21, +1)
, (2), a classifier for removing coarse coal particles from the coal-water slurry generated by (3), and (6) a classifier fi.
, +61 are conveyors which return the coarse coal particles removed to the feed hoppers (7) for the tower mills (21, +1), (2), (3), (8) and (9) are classifiers f
This is a stirring sentry for stirring the coal-water slurry from which coarse coal particles have been removed by No. 41 and +51.

On the other hand, regarding the raw material supply system, (101 is a coal storage tank, (b) is a lime amount adjustment device that adjusts the amount of coal supplied from the coal storage fff flol to the rod mill (1) via the conveyor (6). , (to) is a water storage tank that stores water to be supplied to Roddomi*lI) by a water supply pump (P, ), and α◆ is a water storage tank that stores additives to be supplied to Roddomi (l) by an additive supply pump (P2). This is an additive storage tank. Also, αQ is a conveyor that feeds coal into the coal storage tank (10), and (7) is the coal storage tank (10).
This is a sieve machine that sieves the coal supplied to K.

The coal water slurry that has been stirred in the stirring tanks (81, +91) is passed through the first quality control step αη to the adjustment tank (to).
After being subjected to property adjustment processing in the adjustment tank (to), it is fed to the storage tank (7) via the first quality control process Q1.

The number of days that coal-water slurry can be stored in storage tanks will vary depending on demand, but production adjustments will be made to keep it to a maximum of two months.

In addition, the right coal water slurry stored in the storage tank can be shipped to the demand site in a timely manner via pipelines, tank trucks, etc.

In the figure, fPl is a pump for electrically transmitting the processed material.

In the production system described above, when producing highly concentrated coal water slurry (coal concentration of about 60% or more) for fuel use, various property adjustments are made for quality control. A property adjustment is performed by adjusting the raw material supply amount based on the property detection in the control step aη, and a second quality control process (property A adjustment by adding a conditioning agent based on the visual property detection).

To adjust the property A by adjusting the amount of raw material supplied, the coal particle size in the coal water slurry is first detected in the first quality control step αη, and the coal particle size is adjusted to a predetermined particle size by adjusting the amount of lime supplied based on the detection result. adjust.

Then, with the coal supply amount fixed, the coal concentration of the coal water slurry is detected in the second quality control step a″?), and the water supply amount is adjusted based on the detection result (adjustment of rA additive supply amount). The coal concentration is adjusted to a predetermined concentration by (with fine adjustment of supply amount)
By doing so, the viscosity is adjusted within a predetermined tolerance range.

In other words, coal particle size affects the combustibility of highly concentrated coal-water slurry,
In addition, since this is the most important requirement in terms of fuel quality, which is related to the sprayability in the burner, by giving top priority to adjusting the coal particle size by adjusting the coal supply amount and fixing the lime supply amount, the produced coal The coal particle size in the water slurry is strictly maintained at a predetermined particle size.

Then, when the coal concentration is adjusted by adjusting the water supply amount while the coal supply amount is fixed, the calorific value of the coal-water slurry produced as a fuel is adjusted. For certain high-concentration coal-water slurries, viscosity, which is related to pipe transportability and atomization performance in burners, is an important requirement following the aforementioned coal particle size. Therefore, after adjusting the coal concentration by adjusting the water supply amount, further water supply is necessary. By finely adjusting the amount, the viscosity of the generated coal-water slurry can be kept within a predetermined tolerance range while the coal concentration is as close to the predetermined concentration as possible.
It is maintained closely.

In summary, when adjusting coal particle size by adjusting coal supply amount and adjusting coal concentration and viscosity by adjusting water supply amount as property adjustment by adjusting raw material supply amount, the order of necessity of adjustment is determined by coal particle size. , viscosity, and coal concentration in this order, thereby controlling the various properties of the produced high-concentration coal-water slurry to a state suitable for use as a fuel.

On the other hand, property adjustment by adding a conditioning agent based on property detection in the first quality control process Q0 is performed in the first quality control process Q0.
Detect the pH of the coal-water slurry to be fed to the storage tank at I, and adjust the amount of pH adjuster supplied from the adjuster storage tank (2B to the adjustment tank) based on the detection result. Accordingly, the pH of the coal-water slurry is adjusted to a predetermined value of 0 pHti suitable for storage.

In addition, the property detection in the first quality control process (b) and the first quality control process α, as well as the adjustment of the raw material supply amount and adjustment agent input amount based on the detection results, are carried out in the continuous production process of coal water slurry. It can also be executed automatically under automatic control by the system controller.

[Another example]

Next, another embodiment of the present invention will be described.

Coal particle size adjustment, viscosity adjustment, and coal concentration adjustment are set as 1 in the order of power requirements for 14 properties, and coal particle size adjustment is carried out by adjusting coal supply amount, and viscosity adjustment and coal concentration adjustment are carried out by adjusting water supply amount. In doing so, various changes can be made to the specific adjustment procedure.

Further, various changes can be made to the specific manufacturing procedure of the high concentration coal water slurry.

[Brief explanation of drawings]

The drawing is a diagram showing a highly concentrated coal-water slurry manufacturing system for explaining the present invention in detail. (1), +21, +1), (2), (3)...
...Wet mill.

Claims (1)

[Claims] Coal and water are pulverized and mixed by the wet mills (1), (2), and (3) to produce a coal-water slurry, and the coal particle size of the produced coal-water slurry is adjusted by the wet mills (1), (2).
) and (3), and the viscosity adjustment of the produced coal-water slurry and the coal concentration adjustment are carried out by adjusting the water supply amount to the wet mills (1), (2), and (3), respectively. A method for producing a highly concentrated coal-water slurry, which is carried out by adjusting the coal supply amount by ranking the importance of each of the property adjustments and ranking them in the order of coal particle size adjustment, viscosity adjustment, and coal concentration adjustment. and a method for producing highly concentrated coal-water slurry that adjusts the amount of water supplied.