Calcium liquid production and concentration system

Abstract

The utility model provides a calcium liquid production and concentration system. The calcium liquid production and concentration system comprises a three-stage tail gas washing system, a washing circulating pool and a two-stage mother liquid filter system, the washing circulating pool comprises a first-stage washing circulating pool, a second-stage washing circulating pool and a third-stage washing circulating pool; the third-stage tail gas washing system is circularly communicated with the first-stage washing circulating pool, the second-stage washing circulating pool and the third-stage washing circulating pool; the second-stage mother liquid filter pressing system is circularly communicated with the first-stage washing circulating pool and the second-stage washing circulating pool, and the second-stage mother liquid filter pressing system is communicated with a clarifying tank for storing concentrated calcium liquid; the clarifying tank is communicated with the prilling tower to provide calcium liquid, and the prilling tower is communicated with the three-stage tail gas washing system to convey tail gas. The device has the beneficial effects that the content of impurities such as calcium carbonate in calcium liquid is effectively reduced in the concentration process by synchronously performing concentration and filtration, the blockage and corrosion of pipelines and spray heads of a circulating concentration system can be avoided, the washing and concentration effects are ensured, and the operation period of a calcium chloride production device is prolonged.

Description

Technical Field

[0001] The utility model relates to the field of chemical industry, in particular to a calcium liquid production and concentration system. Background Art

[0002] Anhydrous calcium chloride is very stable, has strong hygroscopicity, and is easily soluble in water. Calcium chloride has a wide range of uses, mainly as a desiccant, dehydrating agent, food additive, antifreeze, etc. At present, the production of industrial anhydrous calcium chloride mostly adopts fluidized bed spray granulation and spray dryer (tower) granulation technology. Usually, calcium chloride mother liquor is used to absorb calcium chloride dust and heat in the granulation tail gas to concentrate the calcium chloride mother liquor. The concentrated calcium chloride mother liquor is pumped into the fluidized bed and other granulation equipment for coating and agglomeration granulation to produce granular anhydrous calcium chloride.

[0003] In the process of using calcium chloride mother liquor to absorb granulation tail gas, due to the long contact time and sufficient mixing of the mother liquor and tail gas, impurities such as carbon dioxide and coal powder in the tail gas are fully dissolved, mixed and reacted in the mother liquor, resulting in severe scaling and corrosion of the washing tower (absorption tower) equipment and pipelines, further causing high turbidity of the calcium liquid, and the shedding of scaling and corroded metal easily clogging the fluidized bed nozzle, thereby causing production bottlenecks such as fluidized bed caking, poor mother liquor concentration effect, and high turbidity of calcium chloride products, which affect the normal production operation of the device, resulting in a short operation cycle of the anhydrous calcium chloride device, frequent inspection and maintenance, and high production costs. Utility Model Content

[0004] Aiming at the deficiencies of the prior art, the invention solves the problems of fluidized bed agglomeration, poor mother liquor concentration effect and high turbidity of calcium chloride product caused by fluidized bed nozzle blockage and calcium liquid washing system structure blockage.

[0005] The utility model provides a calcium liquid production and concentration system, including a three-stage tail gas washing system, a washing circulation pool and a two-stage mother liquid filtration system;

[0006] The washing circulation pool includes a primary washing circulation pool, a secondary washing circulation pool and a tertiary washing circulation pool;

[0007] The three-stage tail gas washing system is cyclically connected with the first-stage washing circulation pool, the second-stage washing circulation pool and the third-stage washing circulation pool;

[0008] The secondary mother hydraulic filter system is cyclically connected with the primary washing circulation pool and the secondary washing circulation pool, and the secondary mother hydraulic filter system is connected with a clarification tank storing concentrated calcium solution;

[0009] The clarification tank is connected to the granulation tower to provide calcium solution, and the granulation tower is connected to the three-stage tail gas washing system to transport tail gas.

[0010] Furthermore, the secondary mother hydraulic filter system includes a primary mother hydraulic filter and a secondary mother hydraulic filter. The primary mother hydraulic filter is provided with an inlet pipe and an outlet pipe connected to a primary washing circulation tank, and the outlet pipe of the primary mother hydraulic filter is provided with a discharge branch pipe connected to a clarification tank; the secondary mother hydraulic filter is provided with an inlet pipe and an outlet pipe connected to a secondary washing circulation tank, and the outlet pipe of the secondary mother hydraulic filter is provided with a discharge branch pipe connected to a clarification tank.

[0011] Furthermore, a branch pipe is provided on the liquid inlet pipe of the secondary mother hydraulic filter to connect to the primary washing circulation tank.

[0012] Furthermore, the liquid inlet pipes of the first-stage mother hydraulic filter and the second-stage mother hydraulic filter are provided with a material transfer pump.

[0013] Furthermore, the three-stage exhaust gas washing system includes a first-stage exhaust gas washing tower, a second-stage exhaust gas washing tower and a third-stage exhaust gas washing tower. The first-stage exhaust gas washing tower is provided with an air inlet pipe and an air outlet pipe connected to the third-stage washing circulation pool. The second-stage exhaust gas washing tower is provided with an air inlet pipe and an air outlet pipe connected to the second-stage washing circulation pool. The third-stage exhaust gas washing tower is provided with an air inlet pipe and an air outlet pipe connected to the first-stage washing circulation pool.

[0014] Furthermore, the air inlet pipes of the first-stage tail gas washing tower, the second-stage tail gas washing tower and the third-stage tail gas washing tower are provided with washing circulation pumps.

[0015] The concentration method of the utility model device specifically comprises the following steps:

[0016] S1. The tail gas in the granulation tower is input into the first-stage tail gas washing tower to form a calcium chloride mother liquor, and then enters the third-stage washing circulation pool, and is circulated and absorbed by the third-stage tail gas washing tower for concentration. The tail gas is initially concentrated by circulated absorption, and the concentration of the calcium chloride mother liquor is controlled to 20-25%, and then transferred to the second-stage washing circulation pool through the transfer pump;

[0017] S2. The initially concentrated calcium solution is absorbed and concentrated by the secondary tail gas scrubber to a calcium chloride mother solution concentration of 35%-39%, and then enters the secondary mother hydraulic filter for circulation filtration. After the turbidity reaches ≤200mg / L, it is transferred to the primary washing circulation pool through the transfer pump;

[0018] S3. The secondary concentrated calcium solution is absorbed and concentrated in the primary tail gas scrubber to a calcium chloride mother liquor concentration of more than 45%, and then enters the primary mother hydraulic filter for circulation filtration. After the turbidity reaches ≤50mg / L, the calcium solution is passed into the clarification tank;

[0019] S4. The calcium liquid in the clarification tank is input into the fluidized bed of the granulation tower to realize the recycling of the calcium liquid.

[0020] As a preferred solution, after S2 is filtered, if the concentration of the calcium chloride mother liquor is above 45% and the turbidity reaches ≤50 mg / L, the calcium liquid is directly input into the clarification tank from the secondary mother hydraulic filter.

[0021] The beneficial effects of the utility model are:

[0022] 1. The utility model can effectively reduce the impurity content of calcium carbonate and other impurities in the calcium solution during the concentration process by simultaneously performing concentration and filtration, thereby avoiding clogging and corrosion of the pipelines and nozzles of the circulating concentration system, ensuring the washing and concentration effect, and extending the operation cycle of the calcium chloride production device. The mother liquor is filtered and used for fluidized bed granulation, which can avoid clogging of the nozzles due to falling fragments such as scaling and corrosion, and further avoid the formation of the fluidized bed.

[0023] 2. The utility model ensures the continuity of calcium chloride mother liquor supply by recycling calcium liquid, ensures the stability and reliability of the production operation of the device, and further reduces the investment cost and floor space of the device.

[0024] 3. The utility model adopts a material transfer pump to transfer materials, which can ensure that the washing circulation system and the circulation filtration system of the washing circulation pool operate independently, avoid the mutual influence of material transfer and circulation operation, and improve the stability of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to make the content of the utility model easier to understand, the utility model is further described in detail according to specific embodiments and in conjunction with the accompanying drawings.

[0026] Figure 1 : Schematic diagram of the structural connection of the utility model.

[0027] Figure 2 : Schematic diagram of the connection of the three-stage tail gas scrubbing system in the utility model

[0028] Figure 3 : A schematic diagram of the connection of the secondary mother hydraulic filter system in the utility model.

[0029] The reference numerals in the accompanying drawings are:

[0030] 1. First-stage washing circulation pool; 2. Second-stage washing circulation pool; 3. Third-stage washing circulation pool; 4. Transfer pump; 6. First-stage mother hydraulic filter; 7. Second-stage mother hydraulic filter; 8. Clarifying tank; 13. First-stage tail gas washing tower; 14. Second-stage tail gas washing tower; 15. Third-stage tail gas washing tower; 16. Washing circulation pump; 19. Granulating tower. DETAILED DESCRIPTION

[0031] To illustrate the features of the present invention, the present invention is further described below with reference to the accompanying drawings and embodiments.

[0032] Example:

[0033] See also Figures 1 to 3 The present embodiment provides a calcium liquid production and concentration system, including a three-stage tail gas washing system, a washing circulation pool and a two-stage mother liquid pressure filtration system, wherein the washing circulation pool includes a first-stage washing circulation pool 1, a second-stage washing circulation pool 2 and a third-stage washing circulation pool 3, the three-stage tail gas washing system is circulated and connected with the first-stage washing circulation pool 1, the second-stage washing circulation pool 2 and the third-stage washing circulation pool 3, the second-stage mother liquid pressure filtration system is circulated and connected with the first-stage washing circulation pool 1 and the second-stage washing circulation pool 2, the second-stage mother liquid pressure filtration system is connected with a clarification tank 8 for storing concentrated calcium liquid, the clarification tank 8 is connected with a granulation tower to provide calcium liquid, and the granulation tower is connected with the three-stage tail gas washing system to transport tail gas. Through simultaneous concentration and filtration, the content of impurities such as calcium carbonate in the calcium liquid is effectively reduced during the concentration process, the clogging and corrosion of the pipelines and nozzles of the circulating concentration system can be avoided, the washing and concentration effect is ensured, and the operation cycle of the calcium chloride production device is extended. The mother liquor is filtered and used for fluidized bed granulation, which can avoid clogging of the nozzle due to falling debris such as scaling and corrosion products, and further avoid fluidized bed caking; and by recycling the calcium liquid, the continuity of the supply of calcium chloride mother liquor is ensured, the stability and reliability of the production operation of the device is guaranteed, and the investment cost and floor space of the device are further reduced.

[0034] Specifically, the secondary mother hydraulic filter system includes a primary mother hydraulic filter 6 and a secondary mother hydraulic filter 7. The primary mother hydraulic filter 6 is provided with an inlet pipe and an outlet pipe connected to the primary washing circulation pool 1, and the outlet pipe of the primary mother hydraulic filter 6 is provided with a discharge branch pipe connected to the clarification tank 8; the secondary mother hydraulic filter 7 is provided with an inlet pipe and an outlet pipe connected to the secondary washing circulation pool 2, and the outlet pipe of the secondary mother hydraulic filter 7 is provided with a discharge branch pipe connected to the clarification tank 8, so as to realize multi-stage filtration of the calcium liquid. The inlet pipe of the secondary mother hydraulic filter 7 is provided with a branch pipe connected to the primary washing circulation pool 1. The calcium liquid that has been initially filtered is transferred.

[0035] In this embodiment, a material transfer pump 4 is also provided on the liquid inlet pipe of the first-stage mother hydraulic filter 6 and the second-stage mother hydraulic filter 7 to improve the filtering efficiency. The material transfer pump is used to transfer the material, which can ensure that the washing circulation system and the circulating filtration system of the washing circulation pool are operated independently, avoid the mutual influence of the material transfer and the circulation operation, and improve the stability of the device.

[0036] Specifically, the three-stage tail gas washing system includes a primary tail gas washing tower 13, a secondary tail gas washing tower 14 and a tertiary tail gas washing tower 15. The primary tail gas washing tower 13 is provided with an air inlet pipe and an air outlet pipe connected to the tertiary washing circulation pool 3, the secondary tail gas washing tower 14 is provided with an air inlet pipe and an air outlet pipe connected to the secondary washing circulation pool 2, and the tertiary tail gas washing tower 15 is provided with an air inlet pipe and an air outlet pipe connected to the primary washing circulation pool 1.

[0037] In this embodiment, a washing circulation pump 16 is further provided on the air inlet pipes of the first-stage tail gas washing tower 13, the second-stage tail gas washing tower 14 and the third-stage tail gas washing tower 15 to improve the concentration efficiency.

[0038] The concentration method of this embodiment specifically comprises the following steps:

[0039] S1. The tail gas in the granulation tower is input into the primary tail gas washing tower 13 to form a calcium chloride mother liquor, and enters the tertiary washing circulation pool 3, and is circulated and absorbed by the tertiary tail gas washing tower 15 for concentration, and the tail gas is initially concentrated by circulated absorption, and the concentration of the calcium chloride mother liquor is controlled to 25%, and then transferred to the secondary washing circulation pool 2 through the transfer pump 4;

[0040] S2. The calcium solution is initially concentrated by the secondary tail gas scrubber 14 and concentrated to a calcium chloride mother liquor concentration of 39%, and then enters the secondary mother hydraulic filter 7 for circulation filtration, the turbidity is 173mg / L ≤ 200mg / L, and is transferred to the primary washing circulation pool 1 by the transfer pump 4;

[0041] S3. The secondary concentrated calcium solution is absorbed and concentrated in the primary tail gas scrubber 13 to a calcium chloride mother liquor concentration of 49%, enters the primary mother hydraulic filter 6 for circulation filtration, the turbidity is 43mg / L≤50mg / L, the calcium solution is passed into the clarification tank 8;

[0042] S4. The calcium liquid in the clarification tank 8 is input into the fluidized bed of the granulation tower to realize the recycling of the calcium liquid.

[0043] The above embodiments and drawings are only used to illustrate the technical solution of the utility model, and are not intended to limit the utility model. The utility model is described in detail with reference to the preferred embodiments. It should be understood by ordinary technicians in this field that the changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the utility model do not deviate from the purpose of the utility model and should also fall within the scope of protection of the claims of the utility model. Other related technical structures not fully disclosed in the utility model are prior art in the field.

Claims

1. A calcium solution production and concentration system, characterized in that: It includes a three-stage tail gas scrubbing system, a scrubbing circulation pool and a two-stage mother liquid filter system; The washing circulation pool includes a primary washing circulation pool, a secondary washing circulation pool and a tertiary washing circulation pool; The three-stage tail gas washing system is cyclically connected with the first-stage washing circulation pool, the second-stage washing circulation pool and the third-stage washing circulation pool; The secondary mother hydraulic filter system is cyclically connected with the primary washing circulation pool and the secondary washing circulation pool, and the secondary mother hydraulic filter system is connected with a clarification tank storing concentrated calcium solution; The clarification tank is connected to the granulation tower to provide calcium solution, and the granulation tower is connected to the three-stage tail gas washing system to transport tail gas.

2. A calcium solution production and concentration system according to claim 1, characterized in that: The secondary mother hydraulic filter system includes a primary mother hydraulic filter and a secondary mother hydraulic filter. The primary mother hydraulic filter is provided with a liquid inlet pipe and a liquid outlet pipe connected to a primary washing circulation pool, and the liquid outlet pipe of the primary mother hydraulic filter is also provided with a discharge branch pipe connected to a clarification tank; the secondary mother hydraulic filter is provided with a liquid inlet pipe and a liquid outlet pipe connected to a secondary washing circulation pool, and the liquid outlet pipe of the secondary mother hydraulic filter is also provided with a discharge branch pipe connected to a clarification tank.

3. A calcium solution production and concentration system according to claim 2, characterized in that: The liquid inlet pipe of the secondary mother hydraulic filter is provided with a branch pipe connected to the primary washing circulation tank.

4. A calcium solution production and concentration system according to claim 3, characterized in that: The liquid inlet pipes of the first-stage mother hydraulic filter and the second-stage mother hydraulic filter are provided with material transfer pumps.

5. A calcium solution production and concentration system according to claim 1, characterized in that: The three-stage tail gas washing system includes a primary tail gas washing tower, a secondary tail gas washing tower and a tertiary tail gas washing tower. The primary tail gas washing tower is provided with an air inlet pipe and an air outlet pipe connected to a tertiary washing circulation pool. The secondary tail gas washing tower is provided with an air inlet pipe and an air outlet pipe connected to the secondary washing circulation pool. The tertiary tail gas washing tower is provided with an air inlet pipe and an air outlet pipe connected to the primary washing circulation pool.

6. A calcium solution production and concentration system according to claim 5, characterized in that: The air inlet pipes of the first-stage tail gas washing tower, the second-stage tail gas washing tower and the third-stage tail gas washing tower are provided with washing circulation pumps.

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