Hexavalent chromium reducing agent mixing device for producing cement

Abstract

The utility model relates to the technical field of environment-friendly cement production, and discloses a hexavalent chromium reducing agent mixing device for cement production, which comprises a stirring granulator, the stirring granulator comprises a stirring cylinder, and a cover body is arranged at a feed port at the top of the stirring cylinder; a powder feeding pipe and an atomizing nozzle are arranged on the cover body; the device further comprises a nitrogen gas source and a liquid storage tank, the liquid storage tank is a closed container with a liquid adding opening in the top, and a sealing cover is movably arranged on the liquid adding opening; the nitrogen source is communicated with an inner cavity of the liquid storage tank through a guide pipe I, and the atomizing nozzle is communicated with the liquid storage tank through a guide pipe II; the end, located on the liquid storage tank, of the second guide pipe extends below the liquid level of the liquid storage tank. According to the utility model, the liquid storage tank for storing the ferrous sulfate solution is in a closed state, and the ferrous sulfate solution is pressed into the stirring cylinder by introducing nitrogen, so that the problem that ferrous ions are easily oxidized into ferric ions due to the fact that the ferrous sulfate solution is in direct contact with a large amount of air is avoided; the reducibility of the reducing agent is ensured, and hexavalent chromium in cement can be effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of environmentally friendly cement production, in particular to a hexavalent chromium reducing agent mixing device for producing cement. Background Art

[0002] In the production process of cement, due to the raw materials and production process, cement and its products often contain a small amount of toxic and harmful substances such as lead, cadmium, and chromium, among which hexavalent chromium is the most harmful. Hexavalent chromium ions are harmful to the human body, causing skin ulcers, dermatitis, etc. at the mildest, and skin or organ cancer at the worst. Secondly, cement products in contact with soil or rainwater will release soluble hexavalent chromium, which will pollute the water system after entering the surface water or underground, and eventually harm the surrounding ecological environment.

[0003] When silica powder, nano-silicon oxide, glass microbeads, floating beads, and nano-alumina are used as dispersants and ferrous sulfate is used as a reducing agent to mix the cement hexavalent chromium reducing agent, the ferrous sulfate crystals are evenly distributed in the skeleton bridged by the dispersant particles. Since a large number of hydroxyl groups are distributed on the surface of the particles, hydrogen bonds can be formed with the crystallization water of ferrous sulfate. The particles are coated on the surface of the ferrous sulfate crystals to form a protective shell, which can prevent high-temperature Fe2+ from contacting oxygen and produce a protective effect, thereby improving the stability of ferrous sulfate in the high-temperature environment inside cement mills and cement storages, thereby making the cement hexavalent chromium reducing agent have stronger high-temperature stability and reducing properties.

[0004] However, the current cement hexavalent chromium reducing agent mixing device adopts a simple stirring form. If ferrous sulfate directly contacts oxygen in the air during the stirring process, the Fe2+ content in the reducing agent will be reduced, affecting the reduction effect. Summary of the invention

[0005] The utility model aims to provide a hexavalent chromium reducing agent mixing device for producing cement. During the mixing process of the hexavalent chromium reducing agent for cement, a liquid storage tank storing a ferrous sulfate solution is in a closed state, and the ferrous sulfate solution is pressed into a mixing tank by introducing nitrogen, thereby avoiding the problem that ferrous ions are easily oxidized to trivalent ferrous ions due to the direct contact of the ferrous sulfate solution with the air. The reducing property of the reducing agent is ensured and the hexavalent chromium in the cement can be effectively reduced.

[0006] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0007] A mixing device for producing hexavalent chromium reducing agent for cement comprises a stirring granulator, the stirring granulator comprises a stirring cylinder, the top of the stirring cylinder is provided with a feed port, a cover body capable of covering the stirring cylinder is arranged at the feed port on the top of the stirring cylinder; a discharge port is arranged at the bottom of the side wall of the stirring cylinder, a movable door panel is hinged at the discharge port; a stirring mechanism and a cutting mechanism are installed in the inner cavity of the stirring cylinder, both of which are driven to rotate by a motor, a powder feed pipe and an atomizing nozzle capable of conveying materials to the inner cavity of the stirring cylinder are arranged on the cover body; a nitrogen gas source and a liquid storage tank are also included, the liquid storage tank is a closed container with a liquid filling port on the top, a sealing cover is movably arranged on the liquid filling port; the nitrogen gas source is connected with the inner cavity of the liquid storage tank through a first conduit, and the atomizing nozzle is connected with the liquid storage tank through a second conduit; the end of the second conduit is located in the liquid storage tank and extends below the liquid level of the liquid storage tank.

[0008] Furthermore, the liquid storage tank is arranged in the refrigeration box.

[0009] Furthermore, the refrigeration box includes a box body, and a heat exchange coil is installed in the box body.

[0010] Furthermore, a diameter expansion section is provided on the second conduit, and a filter screen is provided in the diameter expansion section.

[0011] Furthermore, the expansion section includes two hollow hemispheres arranged opposite to each other, and the conduit 2 is divided into two pipe sections by the expansion section. A hollow hemisphere is arranged on each pipe section. The two hollow hemispheres are fixedly connected by flanges to form a hollow sphere shape and connect the conduit 2 to form an integral structure. The filter screen is located in the hollow sphere.

[0012] Furthermore, the side walls and the bottom of the mixing tank are both provided with a hollow sandwich structure.

[0013] Compared with the prior art, the utility model has the following advantages: during the mixing process of the cement hexavalent chromium reducing agent in the utility model, the liquid storage tank storing the ferrous sulfate solution is in a closed state, and the ferrous sulfate solution is pressed into the mixing tank by introducing nitrogen, thereby avoiding the problem that the ferrous ions generated by the ferrous sulfate solution directly contacting with the air in large quantities and being easily oxidized into trivalent ferrous ions are avoided, thereby ensuring the reducing property of the reducing agent and being able to effectively reduce the hexavalent chromium in the cement. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0015] Figure 1 This is a schematic diagram of the structure of a cement hexavalent chromium reducing agent mixing device in the embodiment;

[0016] Figure 2 This is a schematic diagram of the installation structure of two hollow hemispheres in the diameter expansion section in the embodiment;

[0017] Among them: 1. mixing tank; 2. cover; 3. movable door panel; 4. mixing mechanism; 5. cutting mechanism; 6. powder feeding pipe; 7. atomizing nozzle; 8. nitrogen gas source; 9. liquid storage tank; 10. liquid filling port; 11. conduit 1; 12. conduit 2; 13. box; 14. heat exchange coil; 15. filter screen; 16. hollow hemisphere. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0019] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0020] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0021] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the application is usually placed when in use. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0022] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0023] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0024] like Figure 1 , 2 As shown, a mixing device for producing hexavalent chromium reducing agent for cement comprises a stirring granulator, which comprises a stirring cylinder 1, the top of the stirring cylinder 1 is provided with a feed port, a cover body 2 which can cover the stirring cylinder 1 is arranged at the feed port on the top of the stirring cylinder 1; a discharge port is arranged at the bottom of the side wall of the stirring cylinder 1, and a movable door panel 3 is hinged at the discharge port; a stirring mechanism 4 and a cutting mechanism 5 are installed in the inner cavity of the stirring cylinder 1, the stirring mechanism 4 and the cutting mechanism 5 are driven to rotate by a motor, and a powder feed pipe 6 and an atomizing nozzle 7 which can convey materials to the inner cavity of the stirring cylinder 1 are arranged on the cover body 2; a nitrogen gas source 8 and a liquid storage tank 9 are also included, the liquid storage tank 9 is a closed container with a liquid filling port 10 on the top, and a sealing cover is movably arranged on the liquid filling port 10; the nitrogen gas source 8 is connected to the inner cavity of the liquid storage tank 9 through a conduit 1 11, and the atomizing nozzle 7 is connected to the liquid storage tank 9 through a conduit 2 12; the conduit 2 12 is located at the end of the liquid storage tank 9 and extends below the liquid level of the liquid storage tank 9.

[0025] like Figure 1 , 2As shown, in this embodiment, the powder raw material of the cement hexavalent chromium reducing agent is a mixture of one or more of silicon powder, nano silicon oxide, glass micro beads, floating beads, and nano aluminum oxide in any proportion, and the liquid material is a ferrous sulfate solution; the liquid is pre-added to the liquid storage tank 9, and then the liquid filling port 10 of the liquid storage tank 9 is sealed with a sealing cover; when the cement hexavalent chromium reducing agent is mixed, the powder material is input into the mixing tank 1 through the conveying pipe and the powder feeding pipe 6, and the stirring mechanism 4 stirs the powder material, and the stirring process In the process, the nitrogen gas source 8 is charged into the liquid storage tank 9 through the conduit 1 11, and the air pressure in the liquid storage tank 9 increases, and the ferrous sulfate solution in the liquid storage tank 9 is pressed to the atomizing nozzle 7 through the conduit 2 12, and the ferrous sulfate solution atomized by the atomizing nozzle 7 is sprayed into the mixing tank 1 to wet the powder material; under the high-speed stirring, mixing and shearing action of the stirring mechanism 4 and the cutting mechanism 5, the material gradually forms a granular state, and can eventually be poured out through the discharge port, and the cement hexavalent chromium reducing agent product is obtained after vacuum drying. In the mixing process of the cement hexavalent chromium reducing agent in this embodiment, the liquid storage tank 9 storing the ferrous sulfate solution is in a closed state, and the ferrous sulfate solution is pressed into the mixing tank 1 by passing nitrogen, which avoids the problem that the ferrous ions produced by the ferrous sulfate solution directly contacting with the air in large quantities are easily oxidized to trivalent ferrous ions, ensuring the reducing property of the reducing agent and being able to effectively reduce the hexavalent chromium in the cement.

[0026] like Figure 1 , 2 As shown, heat is generated in the stirring cylinder 1 during the stirring and granulating process, resulting in an increase in the temperature of the material in the stirring cylinder 1, thereby increasing the risk of oxidation of ferrous sulfate. The liquid storage tank 9 in this embodiment is arranged in a refrigeration box, and the temperature of the ferrous sulfate solution is reduced by refrigeration. After being sprayed by the atomizing nozzle 7, the overall temperature in the stirring cylinder 1 can be reduced, thereby avoiding the problem of excessively high material temperature during the stirring and granulating process. The refrigeration box in this embodiment includes a box body 13, and a heat exchange coil 14 is installed in the box body 13. Cooling water or ice water is continuously introduced into the heat exchange coil 14, and the cooling effect of the liquid in the liquid storage tank 9 can be quickly achieved, with low cost and easy operation.

[0027] like Figure 1 , 2As shown, the conduit 2 12 is provided with an expanded diameter section, and a filter 15 is provided in the expanded diameter section. By providing the filter 15 on the conduit 2 12, it is possible to prevent the particulate impurities in the liquid storage tank 9 from entering the conduit 2 12, thereby causing the problem of clogging of the atomizing nozzle 7. The expanded diameter section in this embodiment includes two hollow hemispheres 16 arranged opposite to each other. The conduit 2 12 is divided into two pipe sections by the expanded diameter section, and each pipe section is provided with a hollow hemisphere 16. The two hollow hemispheres 16 are fixedly connected by flanges to enclose a hollow sphere shape and connect the conduit 2 12 to form an integral structure, and the filter 15 is located in the hollow sphere. The filter 15 is prone to clogging after long-term use, which affects the spraying effect of the atomizing nozzle 7. The two hollow hemispheres 16 are disassembled and connected by flanges. When the filter 15 needs to be replaced, it is only necessary to disassemble the flange, take out the filter 15 between the two hollow hemispheres 16, replace it, and then re-fix it, which is convenient for disassembly and assembly.

[0028] like Figure 1 , 2 As shown, the side wall and the bottom of the mixing tank 1 are both provided with a hollow sandwich structure. The bottom and the side wall of the mixing tank 1 are both provided with a hollow sandwich structure, which can reduce the heat exchange between the inside and the outside of the mixing tank 1, and ensure that the mixing tank 1 is always in a low temperature state under the premise that the ferrous sulfate can be refrigerated.

[0029] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A mixing device for producing a hexavalent chromium reducing agent for cement production, comprising a stirring granulator, the stirring granulator comprising a stirring cylinder (1), the top of the stirring cylinder (1) is provided with a feed port, a cover body (2) capable of covering the stirring cylinder (1) is arranged at the feed port on the top of the stirring cylinder (1); a discharge port is arranged at the bottom of the side wall of the stirring cylinder (1), a movable door plate (3) is hinged at the discharge port; a stirring mechanism (4) and a cutting mechanism (5) are installed in the inner cavity of the stirring cylinder (1), the stirring mechanism (4) and the cutting mechanism (5) are both driven to rotate by a motor, and a powder feed pipe (6) and an atomizing nozzle (7) capable of conveying materials to the inner cavity of the stirring cylinder (1) are arranged on the cover body (2); the characteristics are as follows: The invention also comprises a nitrogen gas source (8) and a liquid storage tank (9); the liquid storage tank (9) is a closed container with a liquid filling port (10) on the top, and a sealing cover is movably provided on the liquid filling port (10); the nitrogen gas source (8) is connected to the inner cavity of the liquid storage tank (9) through a first conduit (11); the atomizing nozzle (7) is connected to the liquid storage tank (9) through a second conduit (12); the second conduit (12) is located at the end of the liquid storage tank (9) and extends below the liquid level of the liquid storage tank (9).

2. The hexavalent chromium reducing agent mixing device for producing cement according to claim 1, characterized in that: The liquid storage tank (9) is arranged in a refrigeration box.

3. The hexavalent chromium reducing agent mixing device for producing cement according to claim 2, characterized in that: The refrigeration box comprises a box body (13), and a heat exchange coil (14) is installed in the box body (13).

4. The hexavalent chromium reducing agent mixing device for producing cement according to claim 1, characterized in that: The second conduit (12) is provided with an expanded diameter section, and a filter screen (15) is provided in the expanded diameter section.

5. The hexavalent chromium reducing agent mixing device for producing cement according to claim 4, characterized in that: The diameter expansion section comprises two hollow hemispheres (16) arranged opposite to each other, the second conduit (12) is divided into two pipe sections by the diameter expansion section, each pipe section is provided with a hollow hemisphere (16), the two hollow hemispheres (16) are fixedly connected by flanges to form a hollow sphere shape and connect the second conduit (12) to form an integral structure, and the filter screen (15) is located in the hollow sphere.

6. The hexavalent chromium reducing agent mixing device for producing cement according to any one of claims 2 to 5, characterized in that: The side walls and the bottom of the mixing tank (1) are both provided with a hollow sandwich structure.

Images