A chemical high-temperature mother liquor recycling treatment system

Abstract

This invention proposes a high-temperature mother liquor recycling system for chemical industries, comprising a filter press, a primary washing unit connected to the filter press, and a secondary washing unit. The primary washing unit includes a condenser and a reverse osmosis pure water machine connected in series to exchange heat, cool, and purify the primary washing water to produce pure water. The filter press is cyclically connected to the primary and secondary washing units, allowing the purified water from the primary washing to be used for the secondary washing, and vice versa. By adding a reverse osmosis water treatment device, the pure water treated by reverse osmosis is reused in the filter press washing operation. The secondary washing water is collected and reused in the primary washing, improving the pure water utilization rate. The condenser facilitates heat exchange between the filter press washing water and soft water, lowering the filter press washing water temperature and raising the soft water supply temperature, further reducing energy consumption in the production process and achieving waste heat reuse. This aligns with national energy conservation and emission reduction policies and is highly practical.

Description

Technical Field

[0001] This utility model relates to the field of chemical technology, and in particular to a high-temperature chemical mother liquor recycling system. Background Technology

[0002] In the chemical production sector, chemical products consume a large amount of water, resulting in high water resource consumption. In one workshop, after the product is synthesized in the reactor, the temperature reaches as high as 95 degrees Celsius. After the mother liquor is filtered out in a filter press, it undergoes a first water wash, the temperature of which still reaches above 65 degrees Celsius. Furthermore, to ensure product purity, a second water wash is required to remove the byproducts generated during the reaction. Producing one ton of product requires 4 tons of softened water, of which 2.5 tons are used for washing.

[0003] To reduce water consumption, existing technologies have introduced several measures for the treatment and reuse of mother liquor. For example, Chinese utility model patent CN210103707U, published on February 21, 2020, discloses a chlor-alkali chemical mother liquor treatment and reuse system. This system includes a preliminary treatment unit, a biochemical treatment unit, a sludge separation unit, an ozone oxidation unit, a secondary biochemical treatment unit, an ultrafiltration unit, a reverse osmosis unit, and a reuse treatment unit. The preliminary treatment unit, arranged sequentially according to the water treatment direction, includes a grid, an equalization tank, a self-cleaning filter, and a cooling tower. The mother liquor is processed through the grid to remove larger solid waste, resulting in pretreated mother liquor. This patent utilizes a traditional activated sludge treatment process combined with advanced oxidation and supplemented by aerated biological filters and activated carbon treatment processes for low-pollution water, providing the possibility of mother liquor reuse. Finally, the biochemically treated effluent undergoes deep membrane treatment via ultrafiltration and mixed-bed filtration, ultimately achieving the goal of reusing the mother liquor for production and avoiding the consumption of large amounts of primary water. However, this patent cannot recover and utilize the heat from the mother liquor. Summary of the Invention

[0004] To address the aforementioned technical problems, this utility model proposes a high-temperature chemical mother liquor recycling system, which solves the problem that existing mother liquor recycling systems cannot recover and utilize the heat of the mother liquor.

[0005] To achieve the above objectives, the technical solution of this utility model is implemented as follows:

[0006] A high-temperature chemical mother liquor recycling system includes a filter press, a primary washing unit, and a secondary washing unit connected to the filter press. The primary washing unit contains a condenser and a reverse osmosis pure water machine connected in series to exchange heat, cool, and purify the primary washing water to produce pure water. The filter press is cyclically connected to the primary and secondary washing units, allowing the purified water from the primary washing to be used for the secondary washing, and vice versa. This invention improves pure water utilization by adding a reverse osmosis water treatment device, allowing the purified water to be reused in the filter press washing operation. The secondary washing water is collected and reused in the primary washing, increasing the pure water utilization rate. The condenser facilitates heat exchange between the filter press washing water and soft water, lowering the washing water temperature and raising the soft water supply temperature, further reducing energy consumption during production and achieving waste heat reuse. This aligns with national energy conservation and emission reduction policies and is highly practical.

[0007] Furthermore, a mother liquor tank is also provided, which is connected to the outlet end of the filter press for recovering the mother liquor after filtration. The mother liquor tank is also connected to the concentrate outlet end of the reverse osmosis water purifier for recovering the concentrate produced by the reverse osmosis water purifier.

[0008] Furthermore, the primary washing unit also includes a reverse osmosis water supply tank, which is located between the outlet end of the filter press and the condenser to temporarily store the primary washing water and supply it to the shell side of the condenser; soft water is introduced into the tube side of the condenser to initially cool the primary washing water and heat the soft water.

[0009] Furthermore, a soft water pipe is connected to the inlet end of the condenser tube side, and a second bag filter is connected to the outlet end of the condenser tube side.

[0010] Furthermore, a cooling water pump is installed on the pipeline between the reverse osmosis water supply tank and the condenser; a multi-stage pump is installed on the pipeline between the condenser and the reverse osmosis pure water machine.

[0011] Furthermore, the outlet end of the filter press is connected to a first bag filter for preliminary filtration of the wash water, and the outlet end of the first bag filter is connected to the inlet end of the mother liquor tank and the inlet end of the reverse osmosis water supply tank, respectively.

[0012] Furthermore, the primary washing unit also includes a primary washing tank, the outlet of which is connected to the inlet of the filter press to provide water for primary washing; the inlet of the primary washing tank is connected to the outlet of the first bag filter to recycle secondary washing water.

[0013] Furthermore, the secondary water washing unit also includes a reverse osmosis pure water tank. The inlet end of the reverse osmosis pure water tank is connected to the purified pure water outlet end of the reverse osmosis pure water machine for recycling the pure water after the first water washing and purification. The outlet end of the reverse osmosis pure water tank is connected to the inlet end of the filter press for providing water for the secondary water washing.

[0014] Furthermore, the outlet end of the mother liquor tank is connected to a mother liquor pump for discharging the mother liquor; a primary water washing pump is installed on the pipeline between the outlet end of the primary water washing tank and the filter press; a secondary water washing pump is installed on the pipeline between the outlet end of the reverse osmosis pure water tank and the filter press.

[0015] Furthermore, the mother liquor tank, primary washing tank, reverse osmosis pure water tank, and reverse osmosis supply water tank are all equipped with level gauges.

[0016] The beneficial effects of this utility model are:

[0017] 1. This utility model adds a reverse osmosis water treatment device and uses pneumatic valves, level gauges and other automated control to reuse the pure water after reverse osmosis treatment in the filter press water washing operation. The secondary filter press water is collected and reused in the primary filter press water washing, thereby improving the pure water utilization rate.

[0018] 2. This utility model uses reverse osmosis pure water machine technology to achieve reverse osmosis purification of filter press washing water, thereby reducing the water consumption for chemical product washing.

[0019] 3. This utility model utilizes the waste heat from the primary filter water in the reverse osmosis water supply tank, and uses a condenser to exchange heat between the filter water and soft water, thereby increasing the soft water supply temperature and further reducing energy consumption in the production process. It realizes the reuse of waste heat, which is in line with the national energy conservation and emission reduction industrial policy and has strong practicality. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of this utility model.

[0022] In the diagram: 1. Filter press, 2. First bag filter, 3. Primary wash tank, 4. Primary wash pump, 5. Mother liquor tank, 6. Mother liquor pump, 7. Reverse osmosis pure water tank, 8. Secondary wash pump, 9. Multistage pump, 10. Reverse osmosis pure water machine, 11. Reverse osmosis supply tank, 12. Second bag filter, 13. Cooling water pump, 14. Condenser. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0024] like Figure 1 As shown in Embodiment 1 of this utility model, a chemical high-temperature mother liquor recycling system includes a filter press 1, a primary washing unit and a secondary washing unit connected to the filter press 1; and the filter press 1 is cyclically connected to the primary washing unit and the secondary washing unit, that is, the outlet end of the filter press 1 is connected to the inlet end of the primary washing unit, one outlet end of the primary washing unit is connected to the inlet end of the secondary washing unit, and the outlet end of the secondary washing unit is connected to the inlet end of the filter press 1, so that the pure water purified by the primary washing is used for the secondary washing, and the washing water of the secondary washing is used for the primary washing of the filter press 1.

[0025] The filter press 1 is used to first filter the slurry from the reactor, and the mother liquor after filtration is discharged. After the mother liquor is filtered, the filter press 1 is washed for the first time by a primary water washing unit.

[0026] Specifically, the primary washing unit includes a primary washing tank 3, the outlet of which is connected to the inlet of the filter press 1 to provide water for the primary washing. The primary washing unit also includes a reverse osmosis water supply tank 11, a condenser 14, and a reverse osmosis pure water machine 10 connected in series. The inlet of the reverse osmosis water supply tank 11 is connected to the outlet of the filter press 1. Water from the primary washing tank 3 enters the filter press 1 for the first washing, and then the filter press 1 performs a second filtration. The reverse osmosis water supply tank 11 temporarily stores the primary washing water generated during the first washing process and then inputs it into the shell side of the condenser 14. Soft water is introduced into the tube side of the condenser 14. The primary washing water is cooled by heat exchange in the condenser 14 and then enters the reverse osmosis pure water machine 10. The reverse osmosis pure water machine 10 is equipped with a reverse osmosis (RO) membrane to purify the primary washing water, ultimately producing pure water. Soft water is heated by heat exchange in the condenser 14.

[0027] And, as Figure 1 As shown, a cooling water pump 13 is installed on the pipeline between the reverse osmosis water supply tank 11 and the condenser 14; a multi-stage pump 9 is installed on the pipeline between the condenser 14 and the reverse osmosis pure water machine 10.

[0028] Example 2 differs from Example 1 in that, as Figure 1As shown, the inlet end of the tube side of the condenser 14 is connected to a soft water pipe, and the outlet end of the tube side of the condenser 14 is connected to a second bag filter 12, which is used to filter the soft water that has been heated after heat exchange and to use the soft water as the process water for the reactor.

[0029] Example 3 differs from Example 1 in that, as Figure 1 As shown, the outlet end of the filter press 1 is connected to the inlet end of the reverse osmosis water supply tank 11 via a pipeline. A first bag filter 2 is provided on the pipeline for preliminary filtration of the primary wash water.

[0030] Example 4 differs from Example 3 in that, as Figure 1 As shown, the secondary water washing unit also includes a reverse osmosis pure water tank 7. The inlet end of the reverse osmosis pure water tank 7 is connected to the purified pure water outlet end of the reverse osmosis pure water machine 10 for recycling the pure water after the first water washing and purification. The outlet end of the reverse osmosis pure water tank 7 is connected to the inlet end of the filter press 1 for providing water for the secondary water washing. This allows the pure water purified by heat exchange after the first water washing water is filtered to be used in the filter press 1 for the secondary water washing. During the process, the filter press 1 performs a third filtration.

[0031] Furthermore, a secondary water washing pump 8 is installed on the pipeline between the outlet end of the reverse osmosis pure water tank 7 and the filter press 1 to deliver pure water to the filter press 1 for secondary water washing.

[0032] Example 5 differs from Example 4 in that, as Figure 1 As shown, the inlet end of the primary washing tank 3 is connected to the outlet end of the first bag filter 2, and is used to recover the secondary washing water generated by the filter press 1 during the secondary washing process. This secondary washing water can be used for the first washing of the filter press 1.

[0033] Furthermore, a primary water washing pump 4 is installed on the pipeline between the outlet end of the primary water washing tank 3 and the filter press 1.

[0034] Example 6 differs from Example 5 in that, as Figure 1 As shown, a mother liquor tank 5 is also provided. The mother liquor tank 5 is connected to the outlet end of the filter press 1 for recovering the mother liquor after the first filtration. The mother liquor tank 5 is also connected to the concentrated water outlet end of the reverse osmosis pure water machine 10 for recovering the concentrated water produced by the reverse osmosis pure water machine 10.

[0035] Furthermore, the outlet end of the mother liquor tank 5 is connected to a mother liquor pump 6 for the discharge of the mother liquor;

[0036] Example 7 differs from Example 6 in that, as Figure 1As shown, the mother liquor tank 5, the primary wash tank 3, the reverse osmosis pure water tank 7, and the reverse osmosis supply water tank 11 are all equipped with level gauges. The primary wash tank 3 is equipped with a level gauge L1, the mother liquor tank 5 is equipped with a level gauge L2, the reverse osmosis pure water tank 7 is equipped with a level gauge L3, and the reverse osmosis supply water tank 11 is equipped with a level gauge L4.

[0037] Example 8 differs from Example 7 in that, as Figure 1 As shown, the outlet of the first bag filter 2 is connected to the inlet of the reverse osmosis water supply tank 11 via a first filter press water pipe, which is equipped with a first filter press water inlet valve XV01. The inlet of the primary wash tank 3 is connected to the outlet of the first bag filter 2 via a second filter press water pipe, which is equipped with a filter press water wash water inlet valve XV02. The primary wash tank 3 is equipped with a soft water replenishment pipe, which is equipped with a soft water replenishment valve XV03. The inlet of the mother liquor tank 5 is connected to the outlet of the first bag filter 2 via a filter press mother liquor pipe, which is equipped with a filter press mother liquor valve XV04. The reverse osmosis pure water tank 7 is also equipped with a soft water replenishment pipe, which is equipped with a soft water replenishment valve XV05. The outlet of the reverse osmosis water supply tank 11 is connected to the cooling water pump 13 via a reverse osmosis water supply pipe, which is equipped with a reverse osmosis water supply valve XV06. The inlet end of the tube side of condenser 14 is connected to a soft water pipe, which is equipped with a heat exchange valve XV07. The direction of the flow of filter water or soft water is controlled by various valves, and the liquid level in the corresponding tank is monitored by various level gauges.

[0038] Example 9: The pressure filtration of this utility model has three pressure filtration processes:

[0039] (1) After the slurry from the reactor is transferred into the filter press 1, it is first filtered. The filtered mother liquor is then pumped into the mother liquor tank 5 and then pumped to the sewage network for discharge by the mother liquor pump 6.

[0040] (2) After the mother liquor is fully pressurized, the primary water washing pump 4 is turned on to allow the water from the primary water washing tank 3 to enter the filter press 1 for the first water washing, followed by the second filtration. The water produced by the filtration is initially filtered by the first bag filter 2 and collected in the reverse osmosis water supply tank 11. After heat exchange by the condenser 14, it is then purified by the reverse osmosis pure water machine 10. The purified pure water from the reverse osmosis is transported to the reverse osmosis pure water tank 7, and the reverse osmosis concentrate is discharged into the mother liquor tank 5.

[0041] The reverse osmosis water purifier 10 is interlocked with the liquid levels of the reverse osmosis water supply tank 11 and the reverse osmosis pure water tank 7. The reverse osmosis water purifier 10 operates when the liquid level in the reverse osmosis water supply tank 11 is high; the reverse osmosis water purifier 10 stops when the liquid level in the reverse osmosis water supply tank 11 is low or the liquid level in the reverse osmosis pure water tank 7 is high.

[0042] (3) After the first water washing and filtration is completed, the second water washing pump 8 is started to transport the reverse osmosis pure water in the reverse osmosis pure water tank 7 to the filter press 1 for the second water washing. The second water washing water generated by the filter press is filtered through the first bag filter 2 and then enters the first water washing tank 3 for the first water washing of the filter press 1.

[0043] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any modifications to the technical solutions described in the foregoing embodiments, or equivalent substitutions of some or all of the technical features thereof, within the spirit and principles of the present invention, do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A chemical high-temperature mother liquor recycling system, characterized in that, It includes a filter press (1), a primary water washing unit and a secondary water washing unit connected to the filter press (1). The primary water washing unit is equipped with a condenser (14) and a reverse osmosis pure water machine (10) connected in series to exchange heat and cool down the primary water washing water and produce pure water after purification. The filter press (1) is cyclically connected to the primary water washing unit and the secondary water washing unit, so that the pure water after primary water washing and purification is used for secondary water washing, and the water from secondary water washing is used for primary water washing of the filter press (1).

2. The chemical high-temperature mother liquor recycling system according to claim 1, characterized in that, It is also equipped with a mother liquor tank (5), which is connected to the outlet end of the filter press (1) for recovering the mother liquor after filtration. The mother liquor tank (5) is also connected to the concentrated water outlet end of the reverse osmosis pure water machine (10) for recovering the concentrated water produced by the reverse osmosis pure water machine (10).

3. The chemical high-temperature mother liquor recycling system according to claim 2, characterized in that, The primary water washing unit also includes a reverse osmosis water supply tank (11), which is located between the outlet end of the filter press (1) and the condenser (14) for temporarily storing the primary water washing water and feeding it into the shell side of the condenser (14); soft water is fed into the tube side of the condenser (14) to initially cool the primary water washing water and heat the soft water.

4. The chemical high-temperature mother liquor recycling system according to claim 3, characterized in that, The inlet end of the tube side of the condenser (14) is connected to a soft water pipe, and the outlet end of the tube side of the condenser (14) is connected to a second bag filter (12).

5. The chemical high-temperature mother liquor recycling system according to claim 3 or 4, characterized in that, A cooling water pump (13) is installed on the pipeline between the reverse osmosis water supply tank (11) and the condenser (14); a multi-stage pump (9) is installed on the pipeline between the condenser (14) and the reverse osmosis pure water machine (10).

6. The chemical high-temperature mother liquor recycling system according to claim 3 or 4, characterized in that, The outlet end of the filter press (1) is connected to a first bag filter (2) for preliminary filtration of the wash water. The outlet end of the first bag filter (2) is connected to the inlet end of the mother liquor tank (5) and the inlet end of the reverse osmosis water supply tank (11), respectively.

7. The chemical high-temperature mother liquor recycling system according to claim 6, characterized in that, The primary washing unit also includes a primary washing tank (3), the outlet end of which is connected to the inlet end of the filter press (1) to provide water for primary washing; the inlet end of the primary washing tank (3) is connected to the outlet end of the first bag filter (2) to recover secondary washing water.

8. The chemical high-temperature mother liquor recycling system according to claim 7, characterized in that, The secondary water washing unit also includes a reverse osmosis pure water tank (7), the inlet end of which is connected to the purified pure water outlet end of the reverse osmosis pure water machine (10) for recycling the pure water after the first water washing and purification, and the outlet end of the reverse osmosis pure water tank (7) is connected to the inlet end of the filter press (1) for providing water for the secondary water washing.

9. The chemical high-temperature mother liquor recycling system according to claim 8, characterized in that, The outlet end of the mother liquor tank (5) is connected to a mother liquor pump (6) for the discharge of mother liquor; a primary water washing pump (4) is installed on the pipeline between the outlet end of the primary water washing tank (3) and the filter press (1); a secondary water washing pump (8) is installed on the pipeline between the outlet end of the reverse osmosis pure water tank (7) and the filter press (1).

10. The chemical high-temperature mother liquor recycling system according to claim 9, characterized in that, The mother liquor tank (5), the primary washing tank (3), the reverse osmosis pure water tank (7), and the reverse osmosis supply water tank (11) are all equipped with level gauges.

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