阅读说明：本技术 煤泥冷冻干燥脱水及系统 (Coal slime freeze drying dehydration and system ) 是由 徐宏祥 汪竞争 宁可佳 崔家画 邓久帅 尹亚男 田汉 李文涛 马金庆 于鹏 于超 于 2021-08-26 设计创作，主要内容包括：本申请涉及煤泥水处理技术领域,提供了一种煤泥冷冻干燥脱水方法及系统,其中,煤泥冷冻干燥脱水方法包括：将煤泥水进行沉降和浓缩,获得煤泥水的溢流和底流；将所述煤泥水的底流进行冷冻,使所述煤泥水的底流冻结；将冻结后的煤泥水的底流在真空环境中进行脱水,以使所述煤泥水的底流中的水分升华。通过本申请的技术方案,不仅能够实现去除煤泥中的自由水,还能有效的去除表面水分和毛细管中的水分,实现煤泥的深度脱水,且整个脱水过程安全环保。(The application relates to the technical field of coal slime water treatment, and provides a coal slime freeze drying dehydration method and a system, wherein the coal slime freeze drying dehydration method comprises the following steps: settling and concentrating the slime water to obtain overflow and underflow of the slime water; freezing the underflow of the slime water to freeze the underflow of the slime water; and dehydrating the underflow of the frozen slime water in a vacuum environment so as to sublimate the water in the underflow of the slime water. Through the technical scheme of this application, not only can realize getting rid of the free water in the coal slime, can also effectually get rid of the moisture in surface moisture and the capillary, realize the degree of depth dehydration of coal slime, and whole dehydration process safety ring protects.)

1. A dehydration method for coal slime freeze drying is characterized by comprising the following steps:

settling and concentrating the slime water to obtain overflow and underflow of the slime water;

freezing the underflow of the slime water to freeze the underflow of the slime water;

and dehydrating the underflow of the frozen slime water in a vacuum environment so as to sublimate the water in the underflow of the slime water.

2. The method of claim 1, further comprising, after dewatering the frozen underflow of slurry water in a vacuum environment to sublimate water in the underflow of slurry water:

and heating the frozen underflow of the slime water in a vacuum environment.

3. The method of claim 2,

and controlling the heating temperature of the underflow of the heated and frozen slime water within the range of 30-35 ℃.

4. The method of any one of claims 1 to 3, wherein the freezing the underflow of the coal slurry water to freeze the underflow of the coal slurry water comprises:

placing the underflow of the slime water in a first cooling device to be cooled to 1-3 ℃;

and placing the underflow of the cooled slime water in a second cooling device and freezing to-30 to-50 ℃.

5. The method of claim 4,

the pressure in the second cooling device is less than 100 Pa;

and the freezing time of the underflow of the cooled slime water in the second cooling device is within the range of 3-4 h.

6. The method of claim 4, wherein dewatering the frozen underflow of coal slurry water in a vacuum environment to sublimate water in the underflow of coal slurry water comprises:

and reducing the pressure of the underflow of the coal slime water after freezing in the second cooling device to be within 20Pa so as to sublimate the water in the underflow of the coal slime water.

7. The method of any one of claims 1 to 3, further comprising, prior to freezing the underflow of coal slurry water:

and collecting the overflow of the coal slime water and circulating the overflow to the separation operation.

8. The method according to claim 2 or 3, wherein the freezing underflow of the slime water is heated in a vacuum environment, and after the moisture in the underflow of the slime water is sublimated for the second time, the method further comprises:

and collecting the water sublimated in the underflow of the slime water, and circulating the water to the separation operation.

9. The utility model provides a coal slime freeze drying dewatering system which characterized in that includes:

the concentration tank is used for settling and concentrating the slime water to obtain overflow and underflow of the slime water;

the freezing device is connected with the concentration tank and is used for freezing the underflow of the slime water;

and the vacuum pump is connected with the refrigerating device and used for pumping out air in the refrigerating device so as to enable the refrigerating device to be in a vacuum state and enable moisture in the underflow of the slime water to be sublimated.

10. The coal slurry freeze drying dehydration system of claim 9 further comprising:

the heating device is connected with the refrigerating device and is used for heating the underflow of the coal slime water after being frozen in the refrigerating device; and

and the moisture collecting device is connected with the concentration tank and the refrigerating device, is used for collecting the overflow of the coal slime water and the sublimed moisture of the underflow of the coal slime water, and circulates to the separation operation.

Technical Field

The application relates to the technical field of coal slime water treatment, in particular to a coal slime freeze drying dehydration method and system.

Background

In the related technology, coal preparation plant coal slime water treatment mainly realizes solid-liquid separation through a flocculation-filter pressing process, the process needs to consume a large amount of chemicals, deep dehydration is difficult to realize for fine-particle coal slime, the porosity of a filter cake formed by the fine-particle coal slime is low, the structural gap of the filter cake is small, free water in the coal slime can be effectively removed through a filter pressing mode, but capillary water and particle surface water in micropores in the coal slime filter cake are difficult to remove, so that the water content of the filter cake formed by the fine-particle coal slime is high, working condition accidents often occur, and normal production operation is influenced.

Disclosure of Invention

An object of the embodiment of the first aspect of the present application is to provide a coal slime freeze drying dehydration method, which not only can remove free water in coal slime, but also can effectively remove surface moisture and moisture in capillary tubes, thereby realizing deep dehydration of coal slime.

The first embodiment of the application provides a dehydration method for coal slime freeze drying, which comprises the following steps: settling and concentrating the slime water to obtain overflow and underflow of the slime water; freezing the underflow of the slime water to freeze the underflow of the slime water; and dehydrating the underflow of the frozen slime water in a vacuum environment so as to sublimate the water in the underflow of the slime water.

In the implementation process, the sedimentation and concentration treatment of the slime water can be carried out in a concentration tank, and the slime water can be subjected to solid-liquid separation in the sedimentation process and is divided into overflow and concentrated underflow; the overflow of the slime water is circulated to the separation operation for recycling, and the underflow is frozen, so that the frozen slime water underflow can be obtained, then the frozen slime water underflow enters a vacuum environment, the water in the slime water underflow in the vacuum environment can be subjected to vacuum sublimation, and the dehydration effect can be realized.

In one possible implementation manner, after dewatering the underflow of the frozen slime water in a vacuum environment to sublimate water in the underflow of the slime water, the method further includes: and heating the frozen underflow of the slime water in a vacuum environment.

In the implementation process, as the moisture removed in the redrying stage of the coal slurry is adsorbed on the particle surface by van der waals force, under the premise of ensuring the product quality, the underflow of the coal slurry water needs to be properly heated in the stage so as to increase the temperature of the coal slurry, thereby facilitating the evaporation of the moisture.

In a possible implementation mode, the heating temperature for heating the underflow of the coal slime water after freezing is controlled within the range of 30-35 ℃.

In the implementation process, when the heating temperature is lower than 30 ℃, the temperature is too low to facilitate the evaporation of water, and when the heating temperature is higher than 35 ℃, the frozen coal slime may be decomposed due to too high temperature.

In one possible implementation manner, freezing the underflow of the slime water to freeze the underflow of the slime water includes: placing the underflow of the slime water in a first cooling device to be cooled to 1-3 ℃; and placing the underflow of the cooled slime water in a second cooling device and freezing to-30 to-50 ℃.

In the implementation process, the freezing process is carried out in two steps, firstly, the underflow of the slime water is placed in a first cooling device to be frozen to 1-3 ℃, and primary freezing is realized; then the underflow of the primarily frozen slime water is placed in a second cooling device for secondary freezing, and is frozen to-30 to-50 ℃ to completely freeze the underflow of the slime water so as to be convenient for dehydration of the underflow of the slime water.

In a possible implementation, the pressure in the second cooling device is less than 100 Pa; and the freezing time of the underflow of the cooled slime water in the second cooling device is within the range of 3-4 h.

In the implementation process, the pressure in the second cooling device is smaller than 100Pa, so that the evaporation of the moisture in the second freezing device can be realized in the freezing process, the moisture in the second freezing device is prevented from entering the underflow of the slime water, and meanwhile, the preliminary preparation can be made for vacuum sublimation, so that the underflow of the slime water is convenient for vacuum sublimation.

The cooling time of the underflow of the slime water in the second cooling device is controlled within the range of 3-4 h, so that the underflow of the slime water can be fully frozen, and the vacuum sublimation dehydration is further facilitated.

In one possible implementation manner, the dewatering the underflow of the frozen slime water in a vacuum environment to sublimate water in the underflow of the slime water includes: and reducing the pressure of the underflow of the coal slime water after freezing in the second cooling device to be within 20Pa so as to sublimate the water in the underflow of the coal slime water.

In the implementation process, the pressure of the second cooling device is reduced to be within 20Pa so as to be close to an absolute vacuum state, so that the moisture in the underflow of the slime water is rapidly vacuum sublimated in the second cooling device, and the dewatering efficiency of the slime is improved.

In one possible implementation, before the underflow of the coal slime water is frozen, the method further includes: and collecting the overflow of the coal slime water and circulating the overflow to the separation operation.

In the implementation process, because the slime water can generate overflow and underflow in the sedimentation and concentration processes, the overflow of the slime water is collected and circulated into the separation operation, so that the effects of energy conservation and environmental protection are realized.

In a possible implementation manner, after heating the frozen underflow of the slime water in a vacuum environment to sublimate the water in the underflow of the slime water for the second time, the method further includes: and collecting the water sublimated in the underflow of the slime water, and circulating the water to the separation operation.

In the implementation process, the same as the overflow effect of the collected slime water, the water sublimed in the underflow of the slime water (including the water sublimed for the first time and the water sublimed for the second time) is collected and circulated to enter the separation operation, so that the effects of energy conservation and environmental protection can be realized.

The second aspect of the present application provides in an embodiment a coal slime freeze drying and dewatering system, including: the concentration tank is used for settling and concentrating the slime water to obtain overflow and underflow of the slime water; the freezing device is connected with the concentration tank and is used for freezing the underflow of the slime water; and the vacuum pump is connected with the refrigerating device and used for pumping out air in the refrigerating device so as to enable the refrigerating device to be in a vacuum state and enable moisture in the underflow of the slime water to be sublimated.

In the implementation process, the freezing device is divided into a first freezing box and a second freezing box, the underflow of the slime water is firstly frozen to 1-3 ℃ in the first freezing box, and then is placed into the second freezing box for secondary freezing to-30-50 ℃ so as to completely freeze the underflow of the slime water, which is not only beneficial to improving the product quality, but also convenient for subsequent vacuum sublimation.

In one possible implementation manner, the method further includes: the heating device is connected with the refrigerating device and is used for heating the underflow of the coal slime water after being frozen in the refrigerating device; and the moisture collecting device is connected with the concentration tank and the refrigerating device and used for collecting the overflow of the slime water and the sublimed moisture of the underflow of the slime water and circulating the moisture to the separation operation.

In the coal slime freeze-drying dehydration method provided by the embodiment of the first aspect of the application, the coal slime water can be settled and concentrated in a concentration tank, and the coal slime water can be subjected to solid-liquid separation in the settling process and is divided into overflow and concentrated underflow; the frozen coal slime underflow can be obtained by freezing the coal slime underflow, the frozen coal slime underflow is placed in a vacuum environment, water in the coal slime underflow in the vacuum environment can be sublimated in vacuum, and the dehydration effect can be realized.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments of the present application will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and that those skilled in the art can also obtain other related drawings based on the drawings without inventive efforts.

FIG. 1 is a schematic flow diagram of a dewatering process for freeze-drying coal slurry according to an embodiment of the present disclosure;

FIG. 2 is a schematic flow diagram of a dewatering process for freeze-drying coal slurry according to another embodiment of the present disclosure;

fig. 3 is a schematic block diagram of a dewatering system for coal slurry freeze drying according to an embodiment of the present disclosure.

Icon: 200. a dewatering system for coal slime freeze drying; 201. a concentration tank; 202. a freezing device; 203. a vacuum pump; 204. a heating device; 205. and a moisture collection device.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures. Meanwhile, in the description of the present application, the terms "first", "second", and the like are used only for distinguishing the description, and are not to be construed as indicating or implying relative importance.

In a first aspect, an embodiment of the present application provides a dewatering method for coal slurry freeze-drying, please refer to fig. 1, in which the dewatering method for coal slurry freeze-drying includes:

step S100: and settling and concentrating the slime water to obtain the overflow and the underflow of the slime water.

Step S102: and freezing the underflow of the slime water to freeze the underflow of the slime water.

Step S104: and dehydrating the underflow of the frozen slime water in a vacuum environment so as to sublimate the water in the underflow of the slime water.

In the implementation process, the sedimentation and concentration treatment of the slime water can be carried out in a concentration tank, and the slime water can be subjected to solid-liquid separation in the sedimentation process and is divided into overflow and concentrated underflow; the overflow of the slime water is circulated to the separation operation for recycling, and the underflow is frozen, so that the frozen slime water underflow can be obtained, then the frozen slime water underflow enters a vacuum environment, the water in the slime water underflow in the vacuum environment can be subjected to vacuum sublimation, and the dehydration effect can be realized.

Referring to fig. 2, in a possible implementation manner, after dewatering the underflow of the frozen slime water in a vacuum environment to sublimate water in the underflow of the slime water, the method further includes:

step S106: and heating the frozen underflow of the slime water in a vacuum environment.

In the implementation process, as the moisture removed in the redrying stage of the coal slurry is adsorbed on the particle surface by van der waals force, under the premise of ensuring the product quality, the underflow of the coal slurry water needs to be properly heated in the stage so as to increase the temperature of the coal slurry, thereby facilitating the evaporation of the moisture.

In a possible implementation mode, the heating temperature for heating the underflow of the coal slime water after freezing is controlled within the range of 30-35 ℃.

In the implementation process, when the heating temperature is lower than 30 ℃, the temperature is too low to facilitate the evaporation of water, and when the heating temperature is higher than 35 ℃, the frozen coal slime may be decomposed due to too high temperature.

In one possible implementation manner, freezing the underflow of the slime water to freeze the underflow of the slime water includes: placing the underflow of the slime water in a first cooling device to be cooled to 1-3 ℃; and placing the underflow of the cooled slime water in a second cooling device and freezing to-30 to-50 ℃.

In the implementation process, the freezing process is carried out in two steps, firstly, the underflow of the slime water is placed in a first cooling device to be frozen to 1-3 ℃, and primary freezing is realized; then the underflow of the primarily frozen slime water is placed in a second cooling device for secondary freezing, and is frozen to-30 to-50 ℃ to completely freeze the underflow of the slime water so as to be convenient for dehydration of the underflow of the slime water.

In a possible implementation, the pressure in the second cooling device is less than 100 Pa; and the freezing time of the underflow of the cooled slime water in the second cooling device is within the range of 3-4 h.

In the implementation process, the pressure in the second cooling device is smaller than 100Pa, so that the evaporation of the moisture in the second freezing device can be realized in the freezing process, the moisture in the second freezing device is prevented from entering the underflow of the slime water, and meanwhile, the preliminary preparation can be made for vacuum sublimation, so that the underflow of the slime water is convenient for vacuum sublimation.

The cooling time of the underflow of the slime water in the second cooling device is controlled within the range of 3-4 h, so that the underflow of the slime water can be fully frozen, and the vacuum sublimation dehydration is further facilitated.

In one possible implementation manner, the dewatering the underflow of the frozen slime water in a vacuum environment to sublimate water in the underflow of the slime water includes: and reducing the pressure of the underflow of the coal slime water after freezing in the second cooling device to be within 20Pa so as to sublimate the water in the underflow of the coal slime water.

In the implementation process, the pressure of the second cooling device is reduced to be within 20Pa so as to be close to an absolute vacuum state, so that the moisture in the underflow of the slime water is rapidly vacuum sublimated in the second cooling device, and the dewatering efficiency of the slime is improved.

In one possible implementation, before the underflow of the coal slime water is frozen, the method further includes: and collecting the overflow of the coal slime water and circulating the overflow to the separation operation.

In the implementation process, because the slime water can generate overflow and underflow in the sedimentation and concentration processes, the overflow of the slime water is collected and circulated into the separation operation, so that the effects of energy conservation and environmental protection are realized.

In a possible implementation manner, after heating the frozen underflow of the slime water in a vacuum environment to sublimate the water in the underflow of the slime water for the second time, the method further includes: and collecting the water sublimated in the underflow of the slime water, and circulating the water to the separation operation.

In the implementation process, the same as the overflow effect of the collected slime water, the water sublimed in the underflow of the slime water (including the water sublimed for the first time and the water sublimed for the second time) is collected and circulated to enter the separation operation, so that the effects of energy conservation and environmental protection can be realized.

In a second aspect, please refer to fig. 3, an embodiment of the present application provides a coal slurry freeze-drying dewatering system, including: the concentration tank is used for settling and concentrating the slime water to obtain overflow and underflow of the slime water; the freezing device is connected with the concentration tank and is used for freezing the underflow of the slime water; and the vacuum pump is connected with the refrigerating device and used for pumping out air in the refrigerating device so as to enable the refrigerating device to be in a vacuum state and enable moisture in the underflow of the slime water to be sublimated.

In the implementation process, the freezing device is divided into a first freezing box and a second freezing box, the underflow of the slime water is firstly frozen to 1-3 ℃ in the first freezing box, and then is placed into the second freezing box for secondary freezing to-30-50 ℃ so as to completely freeze the underflow of the slime water, which is not only beneficial to improving the product quality, but also convenient for subsequent vacuum sublimation.

In one possible implementation manner, the method further includes: the heating device is connected with the refrigerating device and is used for heating the underflow of the coal slime water after being frozen in the refrigerating device; and the moisture collecting device is connected with the concentration tank and the refrigerating device and used for collecting the overflow of the slime water and the sublimed moisture of the underflow of the slime water and circulating the moisture to the separation operation.

The above description is only an example of the present application and is not intended to limit the scope of the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.