Saline water filtering device

Abstract

The utility model belongs to the technical field of brine refining, and provides a brine filtering device which comprises a membrane filter and a backflushing tank, a liquid inlet is formed in the side wall of the membrane filter and is communicated to the clarifying barrel through a liquid inlet pipe; a clear liquid opening is formed in the side wall of the membrane filter and is communicated to the baffling groove through a clear liquid pipe; a slag discharging opening is formed in the bottom end of the membrane filter and is communicated to the salty mud tank through a slag discharging pipe; an acid inlet is formed in the side wall of the membrane filter, the acid inlet is communicated to the hydrochloric acid storage tank through an acid inlet pipe, a saline water opening is formed in the side wall of the acid inlet pipe, and the saline water opening is communicated with an outlet of the primary saline water pump; an acid discharge port is formed in the side wall of the membrane filter and is communicated to the backflushing tank through an acid discharge pipe; a back-flushing opening is formed in the side wall of the membrane filter and is communicated to the back-flushing tank through a back-flushing pipe; and the backflushing tank is communicated with the cleaning wastewater tank. The device has the functions of terminal filtration and automatic backwashing pickling, can replace a PE filter in the original process technology, effectively saves the enterprise cost, and reduces the output of solid wastes.

Description

Technical Field

[0001] The utility model belongs to the technical field of brine refining, and particularly relates to a brine filtering device. Background Art

[0002] The primary brine refining process in the brine filtering process is double-alkali method refining + solid-liquid separation by density difference precipitation method. The main equipment for solid-liquid separation by density difference precipitation method is a Dorr clarifier.

[0003] The main process of primary brine refining is as follows: The crude brine in the salt dissolving tank is pumped to the flocculant reaction tank by the crude salt water pump. After adding the flocculant TXY to the crude brine, it overflows to the Dorr clarifier for sedimentation. The brine in the upper part of the Dorr clarifier overflows to the refined brine receiving tank, and the salt mud discharged from the bottom of the central barrel of the Dorr clarifier enters the salt mud receiving tank. The brine in the refined brine receiving tank is pumped to the PE filter by the PE filter feed pump. The refined brine filtered by the PE filter enters the refined brine storage tank, and the salt mud discharged from the bottom of the PE filter during backwashing enters the salt mud receiving tank.

[0004] After the above system runs for a long time, the contents of SS and iron ions in the brine seriously exceed the standard, the cell voltage of the electrolytic cell rises, the electrolysis efficiency drops rapidly, the direct current consumption of caustic soda increases, the operating cost of the caustic soda device increases, and at the same time, it will also affect the safe and stable operation of the electrolysis device. During use, due to solid-liquid separation by density difference precipitation method, more salt mud is generated after adding the high-efficiency flocculant. When using the PE filter for filtration, the PE pipe of each filter needs to be replaced 3 times a year. The salt mud and PE pipe belong to solid waste and need to be treated qualified, which greatly increases the cost of the enterprise. Content of the Utility Model

[0005] Aiming at the deficiencies of the existing technology, the utility model provides a brine filtering device, which has the functions of terminal filtration and automatic backwashing and pickling, and can replace the PE filter in the original process technology.

[0006] To achieve the above object, the utility model adopts the following technical solutions: A brine filtering device includes a membrane filter and a backwash tank;

[0007] A liquid inlet is arranged on the side wall of the membrane filter, and the liquid inlet is communicated with the clarifier through a liquid inlet pipe;

[0008] A clear liquid outlet is arranged on the side wall of the membrane filter, and the clear liquid outlet is communicated with the baffle tank through a clear liquid pipe;

[0009] A slag discharge port is arranged at the bottom end of the membrane filter, and the slag discharge port is communicated with the salt mud pond through a slag discharge pipe;

[0010] An acid inlet is arranged on the side wall of the membrane filter, the acid inlet is communicated with the hydrochloric acid storage tank through an acid inlet pipe, and a brine port is arranged on the side wall of the acid inlet pipe, and the brine port is communicated with the outlet of the primary salt water pump;

[0011] An acid discharge port is provided on the side wall of the membrane filter, and the acid discharge port is connected to the backwash tank through an acid discharge pipe;

[0012] A backwash port is provided on the side wall of the membrane filter, and the backwash port is connected to the backwash tank through a backwash pipe;

[0013] The backwash tank is connected to a cleaning wastewater tank.

[0014] Preferably, a pipe mixer is provided on the acid inlet pipe.

[0015] Preferably, an exhaust port is provided on the side wall of the membrane filter, and the exhaust port is connected to the backwash tank through an exhaust pipe.

[0016] Preferably, a reflux port is provided on the side wall of the membrane filter, and the reflux port is connected to the backwash tank through a reflux pipe.

[0017] Preferably, an overflow tank is provided between the clear liquid outlet and the baffle tank.

[0018] Preferably, a liquid discharge port is provided on the side wall of the slag discharge pipe, and the liquid discharge port is connected to the salt sludge pond through a liquid discharge pipe.

[0019] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0020] 1. A brine filtration device provided by the present utility model has the functions of terminal filtration and automatic backwash pickling, can replace the PE filter in the original process technology, reduces labor costs and operation intensity, and saves the cost of replacing PE pipes and solid waste disposal.

[0021] 2. A brine filtration device provided by the present utility model has full-automatic control for operation, backwash, and pickling, reducing the operation frequency and operation intensity of personnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic connection structure diagram of a brine filtration device provided by an embodiment of the present utility model;

[0023] Figure 2 It is a schematic connection structure diagram when a brine filtration device provided by an embodiment of the present utility model is applied.

[0024] In the drawings, the list of components represented by each reference numeral is as follows:

[0025] 1. Membrane filter; 2. Backwash tank; 3. Feed pipe; 4. Clarification tank; 5. Clear liquid pipe; 6. Baffle tank; 7. Slag discharge pipe; 8. Sludge pond; 9. Acid inlet pipe; 10. Acid discharge pipe; 11. Backwash pipe; 12. Cleaning wastewater tank; 13. Exhaust pipe; 14. Return pipe; 15. Overflow tank; 16. Hydrochloric acid storage tank; 17. Primary brine pump; 18. Drain pipe. Detailed implementation manners

[0026] The following further elaborates on the present utility model in conjunction with specific embodiments, so that those skilled in the art can more clearly understand the present utility model.

[0027] It should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" in the claims should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrally formed structure. For those of ordinary skill in the art, the specific meanings of such terms in this patent can be understood according to specific circumstances.

[0028] As Figure 1 shown, this embodiment provides a brine filtration device, including a membrane filter 1 and a backwash tank 2.

[0029] The membrane filter 1 includes a lower conical part and an upper cylindrical part.

[0030] At the bottom end of the upper cylindrical part of the membrane filter 1, there is a liquid inlet, and the liquid inlet is connected to the clarification tank 4 through a feed pipe 3. The clarification tank 4 is used to provide brine, and the feed pipe 3 is provided with a valve;

[0031] At the top end of the upper cylindrical part of the membrane filter 1, there is a clear liquid outlet, and the clear liquid outlet is connected to the baffle tank 6 through a clear liquid pipe 5. The clear liquid pipe 5 is provided with a valve;

[0032] At the bottom end of the lower conical part of the membrane filter 1, there is a slag discharge port, and the slag discharge port is connected to the sludge pond 8 through a slag discharge pipe 7. The slag discharge pipe 7 is provided with a valve;

[0033] At the top end of the upper cylindrical part of the membrane filter 1, there is an acid inlet, and the acid inlet is connected to the hydrochloric acid storage tank 16 through an acid inlet pipe 9. The acid inlet pipe 9 is provided with a valve. On the side wall of the acid inlet pipe 9, there is a brine port and it is located upstream of the valve. The brine port is connected to the outlet of the primary brine pump 17. The hydrochloric acid storage tank 16 is used to provide electrolytic hydrochloric acid, and there is a valve at the outlet of the hydrochloric acid storage tank 16. The primary brine pump 17 is used to provide refined brine, and there is a valve at the outlet of the primary brine pump 17;

[0034] At the bottom end of the upper cylindrical part of the membrane filter 1, there is an acid discharge port, and the acid discharge port is connected to the backwash tank 2 through an acid discharge pipe 10. The acid discharge pipe 10 is provided with a valve;

[0035] The middle of the lower conical part of the membrane filter 1 is provided with a backwash port, and the backwash port is connected to the backwash tank 2 through a backwash pipe 11, and the backwash pipe 11 is equipped with a valve;

[0036] The backwash tank 2 is communicated with the cleaning waste water tank 12.

[0037] Based on the above structure, the brine filtration device provided in this embodiment includes three usage scenarios.

[0038] 1. Normal operation process

[0039] During use, the brine that has fully reacted in the clarification tank 4 enters the membrane filter 1 from the liquid inlet pipe 3, and is filtered by reverse osmosis through the membrane tube (terminal filtration) until it overflows from the clear liquid port. The qualified refined brine after filtration flows into the baffle tank 6 by gravity, and after adding acid, the pH value is adjusted to 9.5 - 11. After adding sodium sulfite to adjust to no free chlorine (achieved by setting an on-line analyzer), it then flows into the refined brine storage tank, and then is pumped to the secondary brine process by a refined brine pump.

[0040] 2. Drainage and backwash

[0041] During the operation of the membrane filter 1, automatic drainage and backwashing can be achieved. The clear liquid during automatic backwashing is discharged to the cleaning waste water tank 12, and is pumped to the clarified brine storage tank for reuse by a cleaning waste water pump; the salt sludge discharged from the bottom of the membrane filter 1 enters the salt sludge pond, and after being pumped to a filter press by a salt sludge pump for filtration, the clear liquid is reused, and the salt sludge is sent to a qualified manufacturer for treatment.

[0042] 3. Pickling

[0043] After the membrane filter 1 has been operating for a certain period of time, in order to maintain a high filtration capacity and a low filtration pressure, it is necessary to soak and chemically clean it with 15% hydrochloric acid.

[0044] The automatic pickling operation of the membrane filter 1 is as follows (all steps are automatically completed without manual participation):

[0045] ① Check the liquid level of the cleaning waste water tank 12 and control the liquid level of the cleaning waste water tank 12 at about 30%. Check the liquid level of the hydrochloric acid storage tank 16, and control the hydrochloric acid liquid level at about 20% - 70% (15% HCl solution).

[0046] ② Close the valve of the liquid inlet pipe 3 and check whether all cut-off valves are in the closed state.

[0047] ③ Open the cut-off valve of the backwash pipe 11, and drain the brine in the membrane filter 1 into the cleaning waste water tank 12 through the backwash tank 2. After the brine is drained completely, close the cut-off valve of the backwash pipe 11; open the valve of the slag discharge pipe 7, and discharge the bottom salt sludge to the salt sludge pond 8. After discharging completely, close the valve of the slag discharge pipe 7.

[0048] ④ Check whether the valve at the outlet of the hydrochloric acid storage tank 16 is closed. Open the valve at the outlet of the primary brine pump 17 and the cut-off valve of the acid inlet pipe 9. Inject primary brine into the membrane filter 1 for water washing until the water surface covers the flower plate, then close the valve at the outlet of the primary brine pump 17.

[0049] ⑤ Open the cut-off valve of the backwash pipe 11 and drain the primary brine into the cleaning waste water tank 12 (control the liquid level of the cleaning waste water tank 12 at about 30% before draining). After the primary brine is drained completely, close the cut-off valve of the backwash pipe 11 and at the same time close the cut-off valve of the acid inlet pipe 9 (to prevent acid from being accidentally drained into the cleaning waste water tank 12 or the salt sludge pond 8 after acid injection); then open the valve of the slag discharge pipe 7 and discharge the bottom salt sludge into the salt sludge pond 8, and close the valve of the slag discharge pipe 7 after draining.

[0050] ⑥ Open the valve at the outlet of the hydrochloric acid storage tank 16 and the valve at the outlet of the primary brine pump 17, and open the cut-off valve of the acid inlet pipe 9. Mix the refined brine sent by the primary brine pump 17 and the electrolytic hydrochloric acid from the hydrochloric acid storage tank 16. After mixing evenly, it enters from the upper part of the membrane filter 1. When the liquid level of the acidic brine reaches 5 cm below the clear liquid outlet, close the cut-off valve of the acid inlet pipe 9 and soak with acid for about one hour.

[0051] ⑦ Open the cut-off valve of the acid discharge pipe 10 and discharge the acid in the membrane filter 1 from the lower part through the backwash tank 2 into the cleaning waste water tank 12 and then send it to the chemical brine storage tank. After the acidic brine in the middle and upper parts is drained completely, close the cut-off valve of the acid discharge pipe 10 (this step is repeated 7 times); after the 7th time is completed, open the valve of the slag discharge pipe 7 and discharge the acidic brine with a higher mud content into the salt sludge pond 8, and send it to the salt sludge filter press for treatment through the salt sludge pump (during normal operation, the brine enters from the lower part and overflows from the upper part; during pickling, hydrochloric acid enters from the upper part, first discharges the acidic brine with a lower mud content from the lower part, and then discharges the acidic brine with a higher mud content from the bottom to backwash and pickle the membrane tubes, thereby restoring the water production flux of the filter). After the acid is drained completely, close the valve of the slag discharge pipe 7.

[0052] ⑧ Open the valve at the outlet of the primary brine pump 17 and the cut-off valve of the acid inlet pipe 9, inject brine into the membrane filter 1 for water washing until the water surface covers the flower plate, then close the valve at the outlet of the primary brine pump 17 and the cut-off valve of the acid inlet pipe 9. Open the valve of the slag discharge pipe 7 and drain the water into the salt sludge pond 8. After the water is drained completely, close the valve of the slag discharge pipe 7 (this step is repeated).

[0053] ⑨ Open the total liquid inlet valve of the membrane filter 1 and put the membrane filter 1 into operation.

[0054] It should be noted that for some pickling methods in the prior art, 31% high-purity hydrochloric acid needs to be prepared into 15% high-purity hydrochloric acid through a hydrochloric acid storage tank, and then pumped to a membrane filter using a hydrochloric acid pump. The device provided in this embodiment directly sends 15% high-purity hydrochloric acid into the membrane filter 1 through electrolysis, and is equipped with a liquid level interlock, eliminating the need for cooperation between a hydrochloric acid storage tank and a hydrochloric acid pump, reducing energy consumption, investment in system equipment and pipelines, and simultaneously reducing the risk of leakage.

[0055] In summary, the brine filtration device provided in this embodiment has the functions of terminal filtration and automatic backwashing and pickling, can replace the PE filter in the original process technology, reduces labor costs and operation intensity, and saves the costs of replacing PE pipes and solid waste disposal.

[0056] In this embodiment, a pipeline mixer is provided on the acid inlet pipe 9. The pipeline mixer helps the refined brine sent by the primary salt water pump 17 and the electrolytic hydrochloric acid from the hydrochloric acid storage tank 16 to be quickly and evenly mixed.

[0057] An exhaust port is provided at a position slightly below the middle of the columnar part of the membrane filter 1, and the exhaust port is connected to the backwash tank 2 through an exhaust pipe 13. The exhaust port is used to discharge the air accumulated during the filtration process.

[0058] A reflux port is provided at a position slightly above the middle of the columnar part of the membrane filter 1, and the reflux port is connected to the backwash tank 2 through a reflux pipe 14. The reflux port can prevent excessive clear liquid from entering the clear liquid port during backwashing.

[0059] An overflow tank 15 is provided between the clear liquid port and the baffle tank 6, that is, the clear liquid pipe 5 is connected to the overflow tank 15, and the overflow tank 15 is connected to the baffle tank 6. The setting of the overflow tank 15 can prevent excessive liquid from overflowing from the container.

[0060] A liquid discharge port is provided on the side wall of the slag discharge pipe 7, and the liquid discharge port is connected to the sludge pond 8 through a liquid discharge pipe 18. The liquid in the slag discharge pipe 7 can be quickly discharged through the liquid discharge pipe 18.

[0061] In the present utility model, the mechanisms, components, and parts for which no specific structures are described are existing structures that already exist in the prior art and can be directly purchased from the market.

[0062] In the description of the present utility model, it should be understood that the terms "upper", "lower", "left", "right", etc. indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, as well as a specific orientation structure and operation. Therefore, it should not be construed as a limitation to the present utility model. In addition, "first" and "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Therefore, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0063] The above is only a preferred embodiment of the present utility model and is not intended to limit the protection scope of the present utility model. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A salt water filtering device, characterized in that: It comprises a membrane filter (1) and a recoil tank (2); The membrane filter (1) has a liquid inlet on its side wall, and the liquid inlet is connected to the clarification tank (4) through a liquid inlet pipe (3); The side wall of the membrane filter (1) is provided with a clear liquid port, and the clear liquid port is connected to the baffle groove (6) through a clear liquid pipe (5); The bottom end of the membrane filter (1) is provided with a slag discharge port, and the slag discharge port is connected to the salt mud pool (8) through a slag discharge pipe (7); An acid inlet is provided on the side wall of the membrane filter (1), and the acid inlet is connected to the hydrochloric acid storage tank (16) through an acid inlet pipe (9). A brine inlet is provided on the side wall of the acid inlet pipe (9), and the brine inlet is connected to the outlet of a primary brine pump (17); The membrane filter (1) has an acid discharge port on its side wall, and the acid discharge port is connected to the recoil tank (2) through an acid discharge pipe (10); The side wall of the membrane filter (1) is provided with a recoil port, and the recoil port is connected to the recoil tank (2) through a recoil pipe (11); The recoil tank (2) is connected to the cleaning waste water tank (12).

2. A salt water filtering device according to claim 1, characterized in that: The acid inlet pipe (9) is provided with a pipeline mixer.

3. A salt water filtering device according to claim 1, characterized in that: An exhaust port is provided on the side wall of the membrane filter (1), and the exhaust port is connected to the recoil tank (2) through an exhaust pipe (13).

4. A salt water filtering device according to claim 1, characterized in that: A reflux port is provided on the side wall of the membrane filter (1), and the reflux port is connected to the recoil tank (2) via a reflux pipe (14).

5. A salt water filtering device according to claim 1, characterized in that: An overflow tank (15) is provided between the clear liquid outlet and the baffle groove (6).

6. A salt water filtering device according to claim 1, characterized in that: A liquid discharge port is provided on the side wall of the slag discharge pipe (7), and the liquid discharge port is connected to the salt mud pool (8) through a liquid discharge pipe (18).

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