Desulfurized gypsum grinding preparation system and application

Abstract

The invention discloses a desulfurized gypsum grinding preparation system and application, and relates to the technical field of grinding systems, the desulfurized gypsum grinding preparation system comprises a dilution tank, a pre-grinding tank, a grinding machine and a post-grinding tank which are connected in sequence; the inlet end of the before-grinding groove is connected with a first circular vibrating screen, and the outlet end of the grinding machine is connected with a second circular vibrating screen and a third circular vibrating screen which are connected in series. The method solves the problems that a large amount of desulfurized gypsum produced by a thermal power plant is unmarketable under the condition of low real estate industry in the traditional technology, so that the application occasion of the desulfurized gypsum needs to be found again, and the desulfurized gypsum can be used in the papermaking industry and paper-based filler under the continuous research of technicians; but the desulfurized gypsum produced by a thermal power plant is large in particle size and many in impurities, and cannot be directly applied to the paper-based filler.

Description

Technical Field

[0001] The invention relates to the technical field of grinding systems, and in particular to a desulfurized gypsum grinding preparation system. Background Art

[0002] In order to reduce pollution, according to environmental protection requirements, thermal power plants must be equipped with desulfurization systems. Desulfurized gypsum is a byproduct of flue gas desulfurization in thermal power plants. It is currently mainly used directly in cement retarders, building gypsum powder, gypsum board, gypsum blocks, stucco gypsum, self-leveling gypsum, gypsum decorative ceilings and other construction industries. With the domestic and international environment and the recent downturn in the real estate industry, the entire supply chain upstream and downstream industries are weak, the demand for desulfurized gypsum in the construction market has decreased, and the stock has increased, which has seriously affected the recycling of the entire industry chain. There is an urgent need to further expand its application.

[0003] Desulfurized gypsum is also called flue gas desulfurized gypsum, sulfur gypsum or FGD gypsum. Its main component is the same as natural gypsum. Desulfurized gypsum is a by-product of the FGD process. The FGD process is a technology that uses lime-limestone to recover sulfur dioxide in the flue gas of coal or oil. The technology is to grind the lime-limestone into slurry, and pass the dust-removed flue gas containing SO2 through a slurry scrubber to remove SO2. The lime slurry reacts with SO2 to generate calcium sulfate and calcium sulfite. Calcium sulfite is oxidized to calcium sulfate to obtain industrial by-product gypsum, called desulfurized gypsum, which is widely used in building materials and other industries. Before the actual application of desulfurized gypsum, grinding equipment is generally required to grind the blocky desulfurized gypsum into gypsum powder.

[0004] The prior art discloses a patent with a publication number of CN114289134A. The grinding process in the desulfurized gypsum calcining line quantifies the relationship between the grinding body type, gradation and other influencing factors involved in the grinding and the particle size of the gypsum powder, so that the desulfurized gypsum calcining process can save time and efficiently realize the grinding of gypsum powder of qualified quality, accelerate the discharge speed of gypsum products, and further optimize the desulfurized gypsum calcining process; the quality of the gypsum powder produced can avoid the problems of low strength and poor anti-sagging caused by the high water consumption of gypsum mortar during application. The grinding process in the above-mentioned desulfurized gypsum calcining line avoids the disadvantages of the general grinding process that is determined by relying on experience and is relatively arbitrary, which leads to the instability of process operation and product quality control.

[0005] The existing devices including the above patents gradually exposed the shortcomings of the existing technology as they were used, mainly in the following aspects:

[0006] The current downturn in the real estate industry has led to a large amount of desulfurization gypsum produced by thermal power plants being unsalable, which has necessitated the need to find new applications for desulfurization gypsum. Through continuous research by technical personnel, it has been discovered that desulfurization gypsum can be used in the papermaking industry as a paper-based filler. However, the desulfurization gypsum produced by thermal power plants has large particle size and many impurities, and cannot be directly used as a paper-based filler.

[0007] In summary, the prior art obviously has inconveniences and defects in practical use, so it is necessary to improve it. Summary of the invention

[0008] In view of the defects in the prior art, the present invention provides a desulfurization gypsum grinding and preparation system to solve the problem that in the traditional technology, a large amount of desulfurization gypsum produced by thermal power plants is unsalable due to the downturn in the real estate industry, which makes it necessary to find new application occasions for desulfurization gypsum. After continuous research by technical personnel, it is found that desulfurization gypsum can be used in the papermaking industry and used as paper-based filler. However, the desulfurization gypsum produced by thermal power plants has large particle size and many impurities, and cannot be directly used as paper-based filler.

[0009] To achieve the above object, the present invention provides the following technical solutions:

[0010] The desulfurized gypsum grinding preparation system comprises a dilution tank, a pre-grinding tank, a mill and a post-grinding tank which are connected in sequence; the inlet end of the pre-grinding tank is connected to a circular vibrating screen 1, and the outlet end of the mill is connected to circular vibrating screens 2 and 3 which are arranged in series.

[0011] As an optimized solution, a chemical adding tank is connected between the pre-grinding tank and the mill.

[0012] As an optimized solution, an activator is provided in the chemical addition tank.

[0013] As an optimized solution, the active agent includes polyamine, sodium tripolyphosphate, sodium hexametaphosphate and sodium pyrophosphate.

[0014] As an optimized solution, the addition ratio of the polyamine, sodium tripolyphosphate, sodium hexametaphosphate and sodium pyrophosphate is 1.3:0.8:1.7:2.1.

[0015] As an optimized solution, after adding the material into the dilution tank, water is added to dilute it to a concentration of 50-70%, and stirred for 30-60 minutes.

[0016] As an optimized solution, the outlet end of the circular vibrating screen 3 is connected with a buffer tank.

[0017] As an optimized solution, the outlet end of the dilution tank is connected to the inlet end of the circular vibrating screen through a pump-pipe.

[0018] As an optimized solution, the outlet of the chemical addition tank is connected to the inlet of the mill through a pump pipeline.

[0019] As an optimized solution, the outlet end of the buffer tank is connected to the inlet end of the post-grinding tank through a pump three pipeline.

[0020] As an optimized solution, the outlet end of the post-grinding tank is connected to the subsequent processing equipment through a pump four pipeline.

[0021] As an optimized solution, the dilution tank is provided with a material circulation pipeline.

[0022] As an optimized solution, the dilution tank, the pre-grinding tank, the mill and the post-grinding tank are all rotatably provided with anti-settling stirring claws.

[0023] The invention also discloses the application of the desulfurized gypsum grinding and preparation system, including the application to paper-based fillers.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The desulfurized gypsum produced by the thermal power plant is loaded into the dilution tank by a loader, diluted with water to a concentration of about 50-70%, stirred for 30-60 minutes, and passed through the anti-settling stirring claw to ensure uniform dilution without precipitation. One path is returned to the dilution tank through the material circulation pipeline to further increase the dilution effect, and the other path is sent to the circular vibrating screen through the pump pipeline to further screen out large impurities and then enter the pre-mill tank for further dilution and buffering, and then enter the mill through the chemical addition tank;

[0026] The chemicals are added into the tank and the activator is added. The activator has the following four functions:

[0027] Adsorbed on the surface of desulfurized gypsum particles, reducing the surface tension between them and water;

[0028] An adsorption layer is formed on the surface of solid particles, which increases the charge on the surface of desulfurized gypsum particles and forms a reaction force between particles;

[0029] A double-layer structure is formed on the surface of desulfurized gypsum. The polar end of the outer layer has a strong affinity with water, which increases the degree of water wetting of the particles and forms an electrostatic repulsion between the desulfurized gypsum particles.

[0030] According to the properties of raw materials, we jointly develop formulas with chemical manufacturers and compound various types of chemical additives to increase the suspension performance of the mixed liquid, without precipitation and more uniformity;

[0031] The evenly diluted desulfurized gypsum emulsion enters the mill, and after the abrasive is added, the particles collide at high speed, squeeze, rub and stir each other;

[0032] The desulfurized gypsum emulsion treated by the mill is filtered by the second and third circular vibrating screens to remove the residual abrasives and impurities, and then pumped to the buffer tank, and then transported to the post-grinding tank through the third pump pipeline for further grinding, and finally connected to the subsequent processing equipment through the fourth pump pipeline. The treated emulsion can reach a solid content of 50%-70%, a viscosity of 300-1000mpa.s (25℃, S63 / 20), PH6-8, a specific gravity (25℃) of 1.2-1.8, a sieve residue of 325 mesh% <0.5, and a back viscosity of <200mpa.s (25℃, S63 / 20) and other index requirements, and can be used in the field of papermaking;

[0033] This process is a brand-new grinding and preparation process, which effectively expands the application of desulfurization gypsum in power plants and opens up new application areas besides building materials, with good environmental and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the specific embodiments or the description of the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0035] Figure 1 It is a structural schematic diagram of the present invention.

[0036] In the figure: 1-dilution tank, 2-pre-grinding tank, 3-grinding machine, 4-post-grinding tank, 5-circular vibrating screen 1, 6-circular vibrating screen 2, 7-circular vibrating screen 3, 8-chemical adding tank, 9-buffer tank, 10-pump 1 pipeline, 11-pump 2 pipeline, 12-pump 3 pipeline; 13-pump 1 pipeline; 14-anti-settling stirring claw. DETAILED DESCRIPTION

[0037] The following embodiments of the technical solution of the present invention are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore only used as examples, and cannot be used to limit the protection scope of the present invention.

[0038] like Figure 1 As shown, the desulfurized gypsum grinding preparation system includes a dilution tank 1, a pre-grinding tank 2, a mill 3 and a post-grinding tank 4 connected in sequence; the inlet end of the pre-grinding tank 2 is connected to a circular vibrating screen 1 5, and the outlet end of the mill 3 is connected to a circular vibrating screen 2 6 and a circular vibrating screen 3 7 arranged in series.

[0039] The mesh number of circular vibrating screen 1-5 is 50 meshes, and the mesh number of circular vibrating screen 2-6 and circular vibrating screen 3-7 is 150 meshes.

[0040] A chemical adding tank 8 is connected between the pre-grinding tank 2 and the grinding mill 3 .

[0041] The chemical addition tank 8 contains an active agent.

[0042] The function of the dilution tank is to add water to dilute and reduce the concentration. The function of the pre-grinding tank 2 is to buffer and store to facilitate the continuous opening of the mill. The function of the post-grinding tank 4 is to store the finished product.

[0043] Surfactants include polyurethane, sodium tripolyphosphate, sodium hexametaphosphate and sodium pyrophosphate.

[0044] The addition ratio of polyamine, sodium tripolyphosphate, sodium hexametaphosphate and sodium pyrophosphate is 1.3:0.8:1.7:2.1.

[0045] After adding materials into dilution tank 1, add water to dilute to a concentration of 50-70% and stir for 30-60 minutes.

[0046] The outlet end of the circular vibrating screen 7 is connected with a buffer tank 9.

[0047] The outlet end of the dilution tank 1 is connected to the inlet end of the circular vibrating screen 5 through a pump-pipeline.

[0048] The outlet end of the chemical addition tank 8 is connected to the inlet end of the mill 3 through a pump pipe 11.

[0049] The outlet end of the buffer tank 9 is connected to the inlet end of the post-grinding tank 4 through a pump three pipeline 12 .

[0050] The outlet end of the post-grinding tank 4 is connected to the subsequent processing equipment through a pump four pipeline.

[0051] The dilution tank 1 is provided with a material circulation pipeline.

[0052] Anti-settling stirring claws 14 are rotatably provided inside the dilution tank 1, the pre-grinding tank 2, the mill 3 and the post-grinding tank 4.

[0053] The invention also discloses the application of the desulfurized gypsum grinding and preparation system, including the application to paper-based fillers.

[0054] The working process of the present invention is:

[0055] Desulfurized gypsum produced by thermal power plants is loaded into dilution tank 1 by a loader, diluted with water to a concentration of about 50-70%, stirred for 30-60 minutes, and passed through anti-settling stirring claws 14 to ensure uniform dilution without precipitation. One way is returned to dilution tank 1 through the material circulation pipeline to further increase the dilution effect, and the other way is sent to circular vibrating screen 5 through a pump-pipeline to further screen out large impurities and then pumped into pre-grinding tank 2 for further dilution and buffering, and then pumped into mill 3 through chemical addition tank 8;

[0056] The activator is added to the chemical adding tank 8, and the activator has the following four functions:

[0057] Adsorbed on the surface of desulfurized gypsum particles, reducing the surface tension between them and water;

[0058] An adsorption layer is formed on the surface of solid particles, which increases the charge on the surface of desulfurized gypsum particles and forms a reaction force between particles;

[0059] A double-layer structure is formed on the surface of desulfurized gypsum. The polar end of the outer layer has a strong affinity with water, which increases the degree of water wetting of the particles and forms an electrostatic repulsion between the desulfurized gypsum particles.

[0060] According to the properties of raw materials, we jointly develop formulas with chemical manufacturers and compound various types of chemical additives to increase the suspension performance of the mixed liquid, without precipitation and more uniformity;

[0061] The evenly diluted desulfurized gypsum emulsion enters the mill 3, and after the abrasive is added, the particles collide at high speed, squeeze, rub and stir each other;

[0062] The desulfurized gypsum emulsion treated by the mill 3 is filtered by the circular vibrating screen 2 6 and the circular vibrating screen 3 7 to remove the residual abrasive and impurities, and then is pumped to the buffer tank 9, and then transported to the post-grinding tank 4 through the pump 3 pipeline 12 for further grinding, and finally connected to the subsequent processing equipment through the pump 4 pipeline. The treated emulsion can reach a solid content of 50%-70%, a viscosity of 300-1000mpa.s (25℃, S63 / 20), PH6-8, a specific gravity (25℃) of 1.2-1.8, a sieve residue of 325 mesh% <0.5, and a back viscosity <200mpa.s (25℃, S63 / 20) and other index requirements, and can be applied to the papermaking field;

[0063] This process is a brand-new grinding and preparation process, which effectively expands the application of desulfurization gypsum in power plants and opens up new application areas besides building materials, with good environmental and social benefits.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. Desulfurized gypsum grinding and preparation system, characterized by: The invention comprises a dilution tank (1), a pre-grinding tank (2), a grinding mill (3) and a post-grinding tank (4) which are connected in sequence; the inlet end of the pre-grinding tank (2) is connected to a first circular vibrating screen (5), and the outlet end of the grinding mill (3) is connected to a second circular vibrating screen (6) and a third circular vibrating screen (7) which are arranged in series.

2. The desulfurized gypsum grinding and preparation system according to claim 1, characterized in that: A chemical adding tank (8) is connected between the pre-grinding tank (2) and the grinding mill (3).

3. The desulfurized gypsum grinding and preparation system according to claim 1, characterized in that: The chemical addition tank (8) is provided with an active agent.

4. The desulfurized gypsum grinding and preparation system according to claim 3, characterized in that: The active agent includes polyamine, sodium tripolyphosphate, sodium hexametaphosphate and sodium pyrophosphate.

5. The desulfurized gypsum grinding and preparation system according to claim 4, characterized in that: The addition ratio of the polyamine, sodium tripolyphosphate, sodium hexametaphosphate and sodium pyrophosphate is 1.3:0.8:1.7:2.

1.

6. The desulfurized gypsum grinding and preparation system according to claim 1, characterized in that: After adding materials into the dilution tank (1), water is added to dilute the materials to a concentration of 50-70%, and the materials are stirred for 30-60 minutes.

7. The desulfurized gypsum grinding and preparation system according to claim 2, characterized in that: The outlet end of the circular vibrating screen three (7) is connected to a buffer tank (9).

8. The desulfurized gypsum grinding and preparation system according to claim 7, characterized in that: The outlet end of the dilution tank (1) is connected to the inlet end of the circular vibrating screen (5) through a pump one pipeline; the outlet end of the chemical addition tank (8) is connected to the inlet end of the grinding mill (3) through a pump two pipeline (11); and the outlet end of the buffer tank (9) is connected to the inlet end of the post-grinding tank (4) through a pump three pipeline (12).

9. The desulfurized gypsum grinding and preparation system according to claim 1, characterized in that: The dilution tank (1) is provided with a material circulation pipeline.

10. Application of the desulfurized gypsum grinding preparation system according to any one of claims 1 to 9, characterized in that: Includes application to paper-based fillers.

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