Anhydrous calcium chloride production tail gas dust recovery system

Abstract

The utility model relates to the technical field of dust recovery system, specifically is a kind of anhydrous calcium chloride production tail gas dust recovery system, including granulating fluidized bed, the top of granulating fluidized bed is connected with the import of cyclone separator by pipeline, cyclone separator gas outlet is connected with the import of tail gas fan by pipeline, the outlet of tail gas fan is connected with scrubbing tower by pipeline, cyclone separator inside is provided with helical spiral plate;Scrubbing tower is provided with first spray pipe, second spray pipe and third spray pipe from top to bottom;The utility model is set up by spiral plate, and spiral plate makes airflow more stable, rotates more fully, reduces eddy current and energy loss;Classification spraying is washed by spraying by stratification, multiple times, and different content of washing liquid reduces the dust content in tail gas in batch, more effectively improves dust removal effect, absorbs the heat in tail gas simultaneously, reduces heat loss.

Description

Technical Field

[0001] This utility model relates to the technical field of dust recovery systems, specifically a dust recovery system for the tail gas of anhydrous calcium chloride production. Background Technology

[0002] In the production process of anhydrous calcium chloride, a large number of fine particles are generated by the granulation fluidized bed during the production of anhydrous calcium chloride. These particles are generated by the dry air flowing out, resulting in dry exhaust gas with excessive particulate matter. Under normal circumstances, based on the water absorption and dissolution characteristics of anhydrous calcium chloride dust, a water washing tower is usually used to wash the exhaust gas while absorbing heat from the dry air.

[0003] Patent application number 201720135799.4 discloses a continuous production device for granular anhydrous calcium chloride, in which droplets are granulated in a fluidized bed granulation dryer; the exhaust gas enters a cyclone separator for dust removal, and then enters a wet dust collector for further washing of the remaining dust in the hot air.

[0004] The disadvantage of the patent application with application number 201720135799.4 is that the dust removal effect of the cyclone separator and the wet dust collector is poor. Utility Model Content

[0005] The main objective of this invention is to provide a dust recovery system for the tail gas of anhydrous calcium chloride production, in order to solve the problem of poor dust removal efficiency of cyclone separators and wet dust collectors in the existing anhydrous calcium chloride production equipment.

[0006] To achieve the above objectives, this utility model provides a dust recovery system for the tail gas of anhydrous calcium chloride production, including a granulation fluidized bed. The top of the granulation fluidized bed is connected to the inlet of a cyclone separator via a separator inlet pipe. The gas outlet of the cyclone separator is connected to the inlet of a tail gas fan via a separator gas outlet pipe. The outlet of the tail gas fan is connected to a scrubbing tower via a pipe. A baffle is installed inside the cyclone separator, dividing the interior of the cyclone separator into an upper cavity and a lower cavity. The upper cavity and the lower cavity are connected by multiple cavity connecting pipes. Spiral plates are connected to the inner walls of both the cavity connecting pipes and the separator gas outlet pipe. The separator inlet pipe connects to the upper cavity, and the separator gas outlet pipe connects to the lower cavity.

[0007] Furthermore, the washing tower is equipped with a first spray pipe, a second spray pipe, and a third spray pipe from top to bottom; a first material tray is provided below the first spray pipe, the first spray pipe is connected to a first washing tank through a first feed pipe, and the first material tray is connected to the first washing tank through a first return pipe; a second material tray is provided at the bottom of the second spray pipe, the second spray pipe is connected to a second washing tank through a second feed pipe, and the second material tray is connected to the second washing tank through a second return pipe; the third spray pipe is connected to a third washing tank through a third feed pipe, and the bottom of the washing tower is connected to the third washing tank through a third return pipe.

[0008] Furthermore, an auger is installed below the dust outlet of the cyclone separator to collect the dust into a third washing tank.

[0009] Furthermore, the first, second, and third feed pipes are all connected to a liquid inlet pump and a detector for detecting the calcium chloride content.

[0010] Furthermore, the first washing tank is connected to the dust outlet at the bottom of the cyclone separator via a return pipe; a return pump is connected to the return pipe.

[0011] This invention features multiple cavity connecting pipes, each forming a separate vortex, increasing the vortex area and enabling the removal of smaller dust particles for better dust removal. The addition of a spiral plate further stabilizes the airflow, ensuring more complete rotation and reducing eddies and energy loss.

[0012] This invention, by setting up multiple layers of spray nozzles and multiple washing tanks, can control the calcium chloride content in the solution sprayed from each layer of nozzles in a graded manner; the graded spraying reduces the dust content in the exhaust gas by washing and spraying in layers and multiple times, with washing liquids of different contents in batches, which can more effectively improve the dust removal effect, while absorbing heat in the exhaust gas and reducing heat loss.

[0013] This invention, by setting up a return pipe, can use the returned liquid to intermittently flush the dust outlet at the bottom of the cyclone separator, thus preventing the condensation of sediment at the bottom of the cyclone separator. Attached Figure Description

[0014] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

[0015] Figure 1 This is a schematic diagram of the structure of the dust recovery system for the anhydrous calcium chloride production tail gas in the embodiment; Figure 2 This is a schematic diagram of the structure of the cyclone separator in the embodiment; Figure 3 This is a schematic diagram of the structure at the partition in the embodiment; In the diagram: 1. Granulation fluidized bed; 2. Cyclone separator; 201. Baffle plate; 202. Cavity connecting pipe; 203. Separator inlet pipe; 204. Spiral plate; 205. Separator gas outlet pipe; 3. Exhaust gas fan; 4. Scrubber; 5. First nozzle; 6. Second nozzle; 7. Third nozzle; 8. First material tray; 9. First feed pipe; 10. First washing tank; 11. First return pipe; 12. Second material tray; 13. Second feed pipe; 14. Second return pipe; 15. Second washing tank; 16. Third feed pipe; 17. Third washing tank; 18. Third return pipe; 19. Liquid inlet pump; 20. Detector; 21. Return pump; 22. Spiral auger; 23. Return pipe. Detailed Implementation

[0016] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0017] like Figures 1-3 As shown in the embodiment of this utility model, a dust recovery system for the tail gas of anhydrous calcium chloride production is provided, including a granulation fluidized bed 1. The top of the granulation fluidized bed 1 is connected to the inlet of a cyclone separator 2 through a separator inlet pipe 203. The gas outlet of the cyclone separator 2 is connected to the inlet of a tail gas fan 3 through a separator gas outlet pipe 205. The outlet of the tail gas fan 3 is connected to a scrubbing tower 4 through a pipe.

[0018] The cyclone separator 2 is equipped with a baffle 201, which divides the interior of the cyclone separator 2 into an upper cavity and a lower cavity. The upper cavity and the lower cavity are connected by multiple cavity connecting pipes 202. The inner wall of each cavity connecting pipe 202 is connected with a spiral plate 204. The inner wall of the bottom of the separator gas outlet pipe 205 is also connected with a spiral plate 204. The separator inlet pipe is connected to the upper cavity, and the separator gas outlet pipe 205 is connected to the lower cavity.

[0019] The function of the multiple cavity connecting pipes 202 is to form a separate vortex in each cavity connecting pipe 202, increase the vortex area, and remove smaller dust particles, resulting in better dust removal effect; by setting the spiral plate, the spiral plate makes the airflow more stable and the rotation more complete, reducing eddies and energy loss.

[0020] The exhaust gas fan 3 is positioned close to the cyclone separator 2, which can increase the attraction of the gas inside the cyclone separator 2 and improve the dust removal effect of the cyclone separator 2.

[0021] The washing tower 4 is provided with a first spray pipe 5, a second spray pipe 6 and a third spray pipe 7 from top to bottom; a first material tray 8 is provided below the first spray pipe 5, and the first spray pipe 5 is connected to the first washing tank 10 through the first feed pipe 9, and the first material tray 8 is connected to the first washing tank 10 through the first return pipe 11; a second material tray 12 is provided at the bottom of the second spray pipe 6, and the second spray pipe 6 is connected to the second washing tank 15 through the second feed pipe 13, and the second material tray 12 is connected to the second washing tank 15 through the second return pipe 14; the third spray pipe 7 is connected to the third washing tank 17 through the third feed pipe 16, and the bottom of the washing tower 4 is connected to the third washing tank 17 through the third return pipe 18.

[0022] By setting up feed pipes and return pipes, the washing liquid can be circulated and reused, saving water resources.

[0023] The first nozzle 5, the second nozzle 6, and the third nozzle 7 form a three-layer spray washing system. The calcium chloride content in the spray solution in the first washing tank 10 is 40%-48% or higher, the calcium chloride content in the second washing tank 15 is 35%-39% or higher, and the calcium chloride content in the third washing tank 17 is 25%-30% or higher. By setting up multiple layers of nozzles and multiple washing tanks, the calcium chloride content in the solution sprayed from each layer of nozzles can be controlled in stages. The staged spraying reduces the dust content in the exhaust gas by washing and spraying in stages and multiple times, and the washing solution with different contents is used in batches to reduce the dust content in the exhaust gas, which can more effectively improve the dust removal effect, while absorbing the heat in the exhaust gas and reducing heat loss.

[0024] Below the dust outlet of the cyclone separator 2, a spiral auger 22 is installed to collect the dust into the third washing tank 17. The dust at the bottom is dissolved and collected into the washing tank, increasing the calcium content in the washing tank, allowing for repeated recycling and reducing calcium loss.

[0025] The first feed pipe 9, the second feed pipe 13, and the third feed pipe 16 are all connected to a liquid inlet pump 19 and a detector 20 for detecting the calcium chloride content; the detector 20 is an online density meter that monitors the density of the calcium solution and calculates the calcium content.

[0026] The first washing tank 10 is connected to the dust outlet at the bottom of the cyclone separator 2 via a return pipe 23; a return pump 21 is connected to the return pipe 23; by setting up the return pipe, the dust outlet at the bottom of the cyclone separator can be intermittently flushed with the returned liquid, thus preventing the sediment at the bottom of the cyclone separator from condensing.

[0027] The working principle of the above embodiments is as follows: The granulation fluidized bed 1 can achieve stable granulation operation under a negative pressure of 300-800Pa (low negative pressure causes large fluctuations in the material layer, increases the operating load of the blower that blows high-temperature air into the fluidized bed, and easily leads to partial bed caking; high negative pressure causes a large amount of dust to be carried out with the exhaust gas, increasing the difficulty of subsequent dust removal). Therefore, in order not to affect the negative pressure of the system operation, the exhaust gas discharged from the granulation fluidized bed 1 is first transferred to the cyclone separator 2, where a rotating airflow is formed to further separate and settle the particulate matter in the exhaust gas. The settled material is dissolved in washing liquid and then discharged into the washing tank for recycling. The separated exhaust gas is discharged into the washing tower 4 again through the exhaust gas blower 3 for water washing and dust removal, finally meeting the environmental emission requirements.

[0028] Existing dust recovery systems for anhydrous calcium chloride production exhaust gas do not include spiral plates in the cyclone separator, and the scrubbing tower has only one layer of scrubbing system; the calcium chloride content in the treated exhaust gas is 50-80 mg / cm³. 3 .

[0029] The anhydrous calcium chloride production tail gas dust recovery system in this embodiment includes a cyclone separator 2 containing a spiral plate and a scrubbing tower containing a three-layer scrubbing system. The calcium chloride content in the treated tail gas is 10-20 mg / cm³. 3 .

[0030] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A dust recovery system for tail gas from anhydrous calcium chloride production, comprising a granulating fluidized bed (1), wherein the top of the granulating fluidized bed (1) is connected to the inlet of a cyclone separator (2) via a separator inlet pipe (203), the gas outlet of the cyclone separator (2) is connected to the inlet of a tail gas fan (3) via a separator gas outlet pipe (205), and the outlet of the tail gas fan (3) is connected to a scrubbing tower (4) via a pipe, characterized in that, The cyclone separator (2) is provided with a partition (201), which divides the interior of the cyclone separator (2) into an upper cavity and a lower cavity. The upper cavity and the lower cavity are connected by multiple cavity connecting pipes (202). The inner walls of the cavity connecting pipes (202) and the separator gas outlet pipe (205) are connected with spiral plates (204). The separator inlet pipe is connected to the upper cavity, and the separator gas outlet pipe (205) is connected to the lower cavity.

2. The anhydrous calcium chloride production tail gas dust recovery system as described in claim 1, characterized in that, The washing tower (4) is provided with a first spray pipe (5), a second spray pipe (6) and a third spray pipe (7) from top to bottom; a first material tray (8) is provided below the first spray pipe (5), the first spray pipe (5) is connected to the first washing tank (10) through the first feed pipe (9), and the first material tray (8) is connected to the first washing tank (10) through the first return pipe (11); a second material tray (12) is provided at the bottom of the second spray pipe (6), the second spray pipe (6) is connected to the second washing tank (15) through the second feed pipe (13), and the second material tray (12) is connected to the second washing tank (15) through the second return pipe (14); the third spray pipe (7) is connected to the third washing tank (17) through the third feed pipe (16), and the bottom of the washing tower (4) is connected to the third washing tank (17) through the third return pipe (18).

3. The anhydrous calcium chloride production tail gas dust recovery system as described in claim 2, characterized in that, Below the dust outlet of the cyclone separator (2) is a spiral auger (22) for recycling dust to the third washing tank (17).

4. The anhydrous calcium chloride production tail gas dust recovery system as described in claim 2, characterized in that, The first feed pipe (9), the second feed pipe (13) and the third feed pipe (16) are all connected to a liquid pump (19) and a detector (20) for detecting the calcium chloride content.

5. The anhydrous calcium chloride production tail gas dust recovery system as described in claim 2, characterized in that, The first washing tank (10) is connected to the dust outlet at the bottom of the cyclone separator (2) via a return pipe (23); a return pump (21) is connected to the return pipe (23).

Images