Water treatment system and water treatment method based on reverse osmosis membrane

Abstract

The invention discloses a water treatment system and a water treatment method based on a reverse osmosis membrane, the water treatment system comprises a reverse osmosis device ROA, the reverse osmosis device ROA is communicated to a concentrated water collecting box through a concentrated water collecting pipe A; the reverse osmosis device ROB is communicated to the concentrated water collecting box through a concentrated water collecting pipe B; an outlet of the concentrated water collecting box is respectively communicated with a steelmaking slag braising system water tank and an ironmaking slag flushing system water tank; the concentrated water collecting pipe A is communicated with a raw water tank through a concentrated water return pipe A, and the concentrated water collecting pipe B is communicated with the raw water tank through a concentrated water return pipe B; an outlet of the raw water tank is communicated to the ultrafiltration device through the laminated filter; an outlet of the ultrafiltration device is respectively communicated with a reverse osmosis device ROA and a reverse osmosis device ROB through an ultrafiltration water producing tank; wherein each pipeline is provided with a valve for controlling the on-off of the pipeline. The problems that an existing reverse osmosis system is low in overall recovery rate, and concentrated water is difficult to completely consume are solved.

Description

[Technical field]

[0001] The invention belongs to the technical field of reverse osmosis water treatment, and in particular relates to a water treatment system and a water treatment method based on a reverse osmosis membrane. [Background technology]

[0002] Reverse osmosis membrane uses sufficient pressure to separate the solvent (usually water) in the solution through the reverse osmosis membrane (a semi-permeable membrane) in the opposite direction of osmosis. Reverse osmosis method with a pressure greater than the osmotic pressure can be used to separate, purify and concentrate the solution. Reverse osmosis technology can effectively remove impurities such as dissolved salts, colloids, bacteria, viruses, bacterial endotoxins and most organic matter in water. Double membrane separation has a distribution of multiple pore sizes.

[0003] The application of double membrane (ultrafiltration + reverse osmosis) water treatment technology in the water treatment industry is mainly for the purpose of desalination. The salt content in the raw water and the requirements for the salt content in the produced water are the decisive factors in selecting the desalination process.

[0004] The double membrane (ultrafiltration + reverse osmosis) water treatment process has been widely used in the production of desalted water in various industries. Since the recovery rate of the first-stage reverse osmosis is generally around 75%, 25% of the reverse osmosis concentrated water is produced. The reverse osmosis concentrated water has a high salt content and is acidic. It cannot be directly reused in the circulating water system due to its high salt content.

[0005] In the current severe environmental situation, all material yards are enclosed with greenhouses, and water is almost not sprayed, so it is difficult to consume all the concentrated water. The construction cost and operation cost of conventional evaporation and crystallization concentrated water treatment equipment are very high. The discharge of concentrated water from each desalted water station into the sewer increases the production cost of the centralized sewage treatment process. Therefore, how to improve the overall recovery rate of the reverse osmosis system and reduce the discharge volume of concentrated water is a difficult problem facing the industry. [Summary of the invention]

[0006] The purpose of the present invention is to provide a water treatment system and a water treatment method based on a reverse osmosis membrane, so as to solve the problem that the overall recovery rate of the existing reverse osmosis system is low and concentrated water is difficult to be completely consumed.

[0007] The present invention adopts the following technical scheme: a water treatment system based on a reverse osmosis membrane, comprising a reverse osmosis device ROA, which is connected to a concentrated water collection tank via a concentrated water collection pipe A; and further comprising a reverse osmosis device ROB, which is connected to a concentrated water collection tank via a concentrated water collection pipe B; the outlets of the concentrated water collection tank are respectively connected to a water pool of a steelmaking slag stewing system and a water pool of an ironmaking slag flushing system;

[0008] The concentrated water collection pipe A is connected to a raw water pool via concentrated water return pipe A, and the concentrated water collection pipe B is connected to the raw water pool via concentrated water return pipe B; the outlet of the raw water pool is connected to the ultrafiltration device via a laminated filter;

[0009] The outlet of the ultrafiltration device is connected to the reverse osmosis device ROA and the reverse osmosis device ROB respectively through the ultrafiltration water production pool;

[0010] Among them, each pipeline is provided with a valve for controlling the on-off of the pipeline.

[0011] Furthermore, the outlet of the reverse osmosis device ROA is connected to the plant drainage channel through the concentrate discharge pipe A, and the outlet of the reverse osmosis device ROB is connected to the plant drainage channel through the concentrate discharge pipe B.

[0012] Furthermore, the outlet of the plant drainage channel is connected to the water treatment center.

[0013] The second technical solution adopted by the present invention is a water treatment method for improving the concentrated water recovery rate, comprising the following steps:

[0014] Design the volume of the concentrate collection tank according to the reverse osmosis concentrate discharge volume;

[0015] Connect the reverse osmosis device ROA with the concentrated water collection pipe A, disconnect the concentrated water discharge pipe A, and collect the concentrated water into the concentrated water collection tank; connect the reverse osmosis device ROB with the concentrated water collection pipe B, disconnect the concentrated water discharge pipe B, and collect the concentrated water into the concentrated water collection tank;

[0016] The concentrated water collection tank is connected to the water pool of the steelmaking slag stewing system and / or the water pool of the ironmaking slag flushing system.

[0017] Further, the following are included:

[0018] Connect the concentrated water collection pipe A to the concentrated water return pipe A to collect the concentrated water into the raw water tank;

[0019] Connect the concentrated water collection pipe B to the concentrated water return pipe B to collect the concentrated water into the raw water tank;

[0020] The concentrated water in the raw water pool is filtered through the laminated filter and then returned to the ultrafiltration device.

[0021] Further, the following are included:

[0022] When the raw water tank or the concentrate collection tank cannot collect the concentrate, connect the reverse osmosis device ROA with the concentrate discharge pipe A to guide the concentrate to the plant drainage ditch; connect the reverse osmosis device ROB with the concentrate collection pipe B to guide the concentrate to the plant drainage ditch.

[0023] The beneficial effects of the present invention are: part of the reverse osmosis concentrated water is returned to the ultrafiltration device at the front end of the reverse osmosis water inlet, the amount of reflux water is dynamically adjusted to keep the water quality of the inlet water stable, the amount of raw water used and the amount of water discharged into the water treatment center are reduced, the system recovery rate is improved, and the system recovery rate can be increased by 5-10% according to the change of water quality, and the wastewater treatment cost is reduced. At the same time, the reverse osmosis concentrated water is used as water for steelmaking slag stewing and ironmaking slag flushing, which reduces the workload of the original water treatment center for treating concentrated water, and can be directly transported to the water pool for steelmaking slag stewing and ironmaking slag flushing, reducing the treatment cost of concentrated water.

Brief Description of the Drawings

[0024] Figure 1 It is a schematic diagram of the system structure of the present invention.

[0025] Among them, 1. reverse osmosis device ROA, 2. concentrate collection pipe A, 3. concentrate collection box, 4. reverse osmosis device ROB, 5. concentrate collection pipe B, 6. concentrate return pipe A, 7. raw water tank, 8. concentrate return pipe B, 9. laminated filter, 10. ultrafiltration device, 11. ultrafiltration water production tank, 12. concentrate discharge pipe A, 13. plant drainage channel, 14. concentrate discharge pipe B, 15. steelmaking slag stewing system water tank, 16. ironmaking slag flushing system water tank. [Specific implementation method]

[0026] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] The present invention provides a water treatment system based on reverse osmosis membrane, such as Figure 1 As shown, it includes a reverse osmosis device ROA1, which is connected to a concentrated water collection tank 3 via a concentrated water collection pipe A2; it also includes a reverse osmosis device ROB4, which is connected to a concentrated water collection tank 3 via a concentrated water collection pipe B5; the outlets of the concentrated water collection tank 3 are respectively connected to a steelmaking slag stewing system water pool 15 and an ironmaking slag flushing system water pool 16;

[0028] The concentrated water collection pipe A2 is connected to a raw water pool 7 via a concentrated water return pipe A6, and the concentrated water collection pipe B5 is connected to the raw water pool 7 via a concentrated water return pipe B8; the outlet of the raw water pool 7 is connected to an ultrafiltration device 10 via a laminated filter 9;

[0029] The outlet of the ultrafiltration device 10 is connected to the reverse osmosis device ROA1 and the reverse osmosis device ROB4 respectively through the ultrafiltration water production pool 11;

[0030] Among them, each pipeline is provided with a valve for controlling the on-off of the pipeline.

[0031] In some embodiments, the outlet of the reverse osmosis device ROA1 is connected to the plant drainage channel 13 through the concentrate discharge pipe A12, and the outlet of the reverse osmosis device ROB4 is connected to the plant drainage channel 13 through the concentrate discharge pipe B14.

[0032] In some embodiments, the outlet of the plant drainage channel 13 is connected to a water treatment center.

[0033] The present invention also provides a water treatment method for improving the recovery rate of concentrated water, based on a water treatment system based on a reverse osmosis membrane, comprising the following steps:

[0034] Design the volume of the concentrated water collection tank 3 according to the reverse osmosis concentrated water discharge;

[0035] Connect the reverse osmosis device ROA1 to the concentrated water collection pipe A2, disconnect the concentrated water discharge pipe A12, and collect the concentrated water into the concentrated water collection tank 3; connect the reverse osmosis device ROB4 to the concentrated water collection pipe B5, disconnect the concentrated water discharge pipe B14, and collect the concentrated water into the concentrated water collection tank 3;

[0036] The concentrated water collection tank 3 is connected to the water pool of the steelmaking slag stewing system and / or the water pool of the ironmaking slag flushing system.

[0037] Among them, the water used for steelmaking slag stewing is mainly used to reduce the temperature of steel slag, so that the steel slag can be powdered after absorbing water, which is easy to handle later. Ironmaking slag flushing refers to the process of using water to cool the slag in the blast furnace to form water slag during the ironmaking process. The temperature of the concentrated water at the outlet of the reverse osmosis membrane is usually between 5 and 45 degrees Celsius, which can be used to reduce the temperature of steel slag or cool the slag in the blast furnace, so that most of the concentrated water output by the reverse osmosis system is consumed.

[0038] In some embodiments, the following are also included:

[0039] Connect the concentrated water collection pipe A2 to the concentrated water return pipe A6 to collect the concentrated water into the raw water tank 7;

[0040] Connect the concentrated water collection pipe B5 to the concentrated water return pipe B8 to collect the concentrated water into the raw water tank 7;

[0041] The concentrated water in the raw water tank 7 is filtered through the laminated filter 9 and then returned to the ultrafiltration device 10.

[0042] In some embodiments, the following are also included:

[0043] When the raw water tank 7 or the concentrate collection tank 3 cannot collect concentrate, the reverse osmosis device ROA1 is connected to the concentrate discharge pipe A12 to guide the concentrate to the plant drainage ditch 13; the reverse osmosis device ROB4 is connected to the concentrate collection pipe B5 to guide the concentrate to the plant drainage ditch 13.

[0044] The water treatment system based on reverse osmosis membrane of the present invention returns part of the reverse osmosis concentrated water to the ultrafiltration device at the front end of the reverse osmosis water inlet, dynamically adjusts the amount of reflux water to keep the water quality of the inlet water stable, reduces the amount of raw water used and the amount of water discharged into the water treatment center, improves the system recovery rate, and can increase the system recovery rate by 5-10% according to the change of water quality, and reduces the cost of wastewater treatment. At the same time, the reverse osmosis concentrated water is used as water for steelmaking slag stewing and ironmaking slag flushing, which reduces the workload of the original water treatment center for treating concentrated water, and can be directly transported to the water pool for steelmaking slag stewing and ironmaking slag flushing, reducing the treatment cost of concentrated water.

Claims

1. A water treatment system based on reverse osmosis membrane, characterized in that: The invention comprises a reverse osmosis device ROA (1), the reverse osmosis device ROA (1) being connected to a concentrated water collection tank (3) via a concentrated water collection pipe A (2); and a reverse osmosis device ROB (4), the reverse osmosis device ROB (4) being connected to a concentrated water collection tank (3) via a concentrated water collection pipe B (5); the outlets of the concentrated water collection tank (3) are respectively connected to a water pool (15) of a steelmaking slag stewing system and a water pool (16) of an ironmaking slag flushing system; The concentrated water collection pipe A (2) is connected to a raw water pool (7) via a concentrated water return pipe A (6), and the concentrated water collection pipe B (5) is connected to the raw water pool (7) via a concentrated water return pipe B (8); the outlet of the raw water pool (7) is connected to an ultrafiltration device (10) via a laminated filter (9); The outlet of the ultrafiltration device (10) is connected to the reverse osmosis device ROA (1) and the reverse osmosis device ROB (4) respectively through the ultrafiltration water production pool (11); Among them, each pipeline is provided with a valve to control the on-off of the pipeline.

2. A water treatment system based on reverse osmosis membrane according to claim 1, characterized in that: The outlet of the reverse osmosis device ROA (1) is connected to the plant drainage channel (13) through the concentrated water discharge pipe A (12), and the outlet of the reverse osmosis device ROB (4) is connected to the plant drainage channel (13) through the concentrated water discharge pipe B (14).

3. A water treatment system based on reverse osmosis membrane according to claim 1 or 2, characterized in that: The outlet of the plant drainage channel (13) is connected to the water treatment center.

4. A water treatment method for improving the recovery rate of concentrated water, characterized in that: A water treatment system based on a reverse osmosis membrane according to any one of claims 1 to 3, comprising the following steps: The volume of the concentrate collection tank (3) is designed according to the discharge volume of the reverse osmosis concentrate; Connecting the reverse osmosis device ROA (1) with the concentrated water collection pipe A (2), disconnecting the concentrated water discharge pipe A (12), and collecting the concentrated water into the concentrated water collection tank (3); connecting the reverse osmosis device ROB (4) with the concentrated water collection pipe B (5), disconnecting the concentrated water discharge pipe B (14), and collecting the concentrated water into the concentrated water collection tank (3); The concentrated water collection tank (3) is connected to the water pool of the steelmaking slag stewing system and / or the water pool of the ironmaking slag flushing system.

5. A water treatment method for improving concentrated water recovery rate according to claim 4, characterized in that: Includes the following: Connecting the concentrated water collection pipe A (2) to the concentrated water return pipe A (6) to collect the concentrated water into the raw water tank (7); Connecting the concentrated water collection pipe B (5) to the concentrated water return pipe B (8) to collect the concentrated water into the raw water tank (7); The concentrated water in the raw water pool (7) is filtered through the laminated filter (9) and then returned to the ultrafiltration device (10).

6. A water treatment method for improving concentrated water recovery rate according to claim 4, characterized in that: Includes the following: When the raw water tank (7) or the concentrate collection tank (3) cannot collect concentrate, the reverse osmosis device ROA (1) is connected to the concentrate discharge pipe A (12) to guide the concentrate to the plant drainage channel (13); the reverse osmosis device ROB (4) is connected to the concentrate collection pipe B (5) to guide the concentrate to the plant drainage channel (13).

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