Production system for stabilizing RO membrane produced water recovery rate

Abstract

The utility model belongs to the technical field of membrane separation systems, and particularly relates to a production system for stabilizing the RO membrane produced water recovery rate. According to the technical scheme, the production system capable of stabilizing the RO membrane produced water recovery rate comprises a raw water tank, an RO membrane separator and a circulating water heat exchanger, an outlet of the raw water tank is connected with the RO membrane separator through a pipeline, and external supply raw water is divided into two paths to be fed into a tube pass inlet of the raw water tank or a tube pass inlet of the circulating water heat exchanger; a tube pass outlet of the circulating water heat exchanger is connected with the raw water tank through a pipeline, collected circulating return water is fed into a shell pass inlet of the circulating water heat exchanger, and the shell pass outlet of the circulating water heat exchanger sends out the circulating return water after heat exchange to the water cooling tower. The utility model provides a production system for stabilizing the recovery rate of water produced by an RO (Reverse Osmosis) membrane.

Description

Technical Field

[0001] The utility model belongs to the technical field of membrane separation systems, and in particular relates to a production system for stabilizing the water production recovery rate of an RO membrane. Background Art

[0002] RO reverse osmosis equipment is a high-end equipment used for water treatment. It filters raw water through an RO membrane to remove impurities, viruses, bacteria and other harmful substances, and produces purified water. Using RO membranes to produce pure water is currently the most widely used production method for small and medium-sized users.

[0003] Under normal circumstances, the pure water production rate of a reverse osmosis membrane is typically between 50% and 75%. The water production capacity of a complete system is specified based on the standard water production of the RO membrane at a water temperature of 25°C. In actual operation, raw water temperature is a key factor influencing RO membrane performance, including water quality, water production rate, and service life. As raw water temperature increases, the movement of water molecules accelerates, the osmotic pressure decreases, and water molecules pass through the reverse osmosis membrane more easily. Within the range of 15 to 35°C, water production increases by approximately 3% for every 1°C increase in water temperature. Similarly, especially in winter, when raw water temperature drops, the viscosity of water increases, and the diffusivity of water decreases. Under the same operating conditions, water production can decrease by 3% to 4% for every 1°C drop in temperature. Utility Model Content

[0004] In order to solve the above problems existing in the prior art, the purpose of the present invention is to provide a production system for stabilizing the water recovery rate of RO membrane.

[0005] The technical solution adopted by this utility model is:

[0006] A production system for stabilizing the recovery rate of RO membrane water production includes a raw water tank, an RO membrane separator, and a circulating water heat exchanger. The outlet of the raw water tank is connected to the RO membrane separator via a pipeline. Externally supplied raw water is divided into two paths and respectively sent to the raw water tank or the tube-side inlet of the circulating water heat exchanger. The tube-side outlet of the circulating water heat exchanger is connected to the raw water tank via a pipeline. Circulating water return water is sent to the shell-side inlet of the circulating water heat exchanger, and circulating water return water is sent out from the shell-side outlet of the circulating water heat exchanger.

[0007] The key issue that needs to be addressed is the significant drop in water production from RO reverse osmosis equipment caused by low raw water temperature in winter. This is due to the need to maintain the raw water temperature fluctuation within a reasonable and controllable range. The utility model can achieve controllable regulation of the raw water temperature through heat exchange.

[0008] Production workshops often have circulating water and cooling tower system devices, that is, the production heat exchange equipment needs to use circulating water for process temperature adjustment. The low-grade circulating return water collected after heat exchange is cooled by the cooling tower (the temperature difference can generally be reduced by 5℃ to 15℃) and then pumped and recycled again.

[0009] The utility model uses the circulating return water as a low-grade heat source to perform heat exchange with low-temperature raw water. Firstly, the raw water temperature can be increased, which is beneficial for the RO device to increase the water production rate. Secondly, the circulating return water temperature can be reduced, which reduces the workload of the cooling tower.

[0010] As a preferred solution of the present invention, a circulating water cooling tower is provided on the circulating water return pipeline, and the circulating water cooling tower delivers circulating water.

[0011] As a preferred solution of the present invention, a regulating pipeline is connected between the pipeline before the circulating water returns to the circulating water heat exchanger and the pipeline for the circulating water returns to the circulating water heat exchanger, and a bypass flow regulating valve is connected to the regulating pipeline.

[0012] As a preferred solution of the present invention, a temperature indicator is connected to the pipeline between the pipe outlet of the circulating water heat exchanger and the raw water tank, and the temperature indicator is connected to the bypass flow regulating valve signal.

[0013] When the raw water and circulating water return water exchange heat in the circulating water heat exchanger, the temperature of the raw water after heat exchange is monitored by the temperature indicator, and the regulating valve on the regulating pipeline is controlled according to the temperature. The flow rate of the circulating water return water entering the circulating water heat exchanger is adjusted accordingly to control the raw water temperature.

[0014] As a preferred solution of the present invention, a pre-processor is connected to the pipeline between the raw water tank and the RO membrane separator. The pre-processor removes mechanical and biological impurities by filtering.

[0015] As a preferred solution of the present invention, the RO membrane separator is connected to the product pure water collection tank and the separation concentrated water collection tank through pipelines.

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

[0017] The utility model uses the circulating return water as a low-grade heat source to perform heat exchange with low-temperature raw water. Firstly, the raw water temperature can be increased, which is beneficial for the RO device to increase the water production rate. Secondly, the circulating return water temperature can be reduced, which reduces the workload of the cooling tower. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural diagram of the present utility model.

[0019] In the figure: 1-raw water tank; 2-RO membrane separator; 3-circulating water heat exchanger; 4-circulating water cooling tower; 5-bypass flow control valve; 6-temperature indicator; 7-pre-processor; 8-product pure water collection tank; 9-separated concentrated water collection tank. DETAILED DESCRIPTION

[0020] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without inventive effort are within the scope of protection of the present invention. It should be noted that the embodiments of the present invention and the features therein may be combined with each other unless there is a conflict.

[0022] like Figure 1 As shown, the production system for stabilizing the RO membrane water production recovery rate of this embodiment includes a raw water tank 1, an RO membrane separator 2 and a circulating water heat exchanger 3. The outlet of the raw water tank 1 is connected to the RO membrane separator 2 through a pipeline. The external raw water is divided into two paths and respectively sent to the raw water tank 1 or the tube side inlet of the circulating water heat exchanger 3. The tube side outlet of the circulating water heat exchanger 3 is connected to the raw water tank 1 through a pipeline. The circulating water return is sent to the shell side inlet of the circulating water heat exchanger 3. The shell side outlet of the circulating water heat exchanger 3 sends the circulating water return to the circulating water cooling tower 4.

[0023] The circulating water supply pipeline is provided with a circulating water cooling tower 4. The pipeline between the raw water tank 1 and the RO membrane separator 2 is connected to a pre-processor 7. The pre-processor 7 removes mechanical and biological impurities by filtering.

[0024] The key issue that needs to be addressed is the significant drop in water production from RO reverse osmosis equipment caused by low raw water temperature in winter. This is due to the need to maintain the raw water temperature fluctuation within a reasonable and controllable range. The utility model can achieve controllable regulation of the raw water temperature through heat exchange.

[0025] Production workshops often have circulating water and cooling tower system devices, that is, the production heat exchange equipment needs to use circulating water for process temperature adjustment. The low-grade circulating return water collected after heat exchange is cooled by the cooling tower (the temperature difference can generally be reduced by 5℃ to 15℃) and then pumped and recycled again.

[0026] The utility model uses the circulating return water as a low-grade heat source to perform heat exchange with low-temperature raw water. Firstly, the raw water temperature can be increased, which is beneficial for the RO device to increase the water production rate. Secondly, the circulating return water temperature can be reduced, which reduces the workload of the cooling tower.

[0027] Furthermore, a regulating pipeline is connected between the pipeline before the circulating water returns to the circulating water heat exchanger 3 and the pipeline for the circulating water returns to the circulating water heat exchanger 3 , and a bypass flow regulating valve 5 is connected to the regulating pipeline.

[0028] A temperature indicator 6 is connected to the pipeline between the pipe outlet of the circulating water heat exchanger 3 and the raw water tank 1 , and the temperature indicator 6 is signal-connected to the bypass flow regulating valve 5 .

[0029] When the raw water and the circulating water return water exchange heat in the circulating water heat exchanger 3, the temperature of the raw water after the heat exchange is monitored by the temperature indicator 6, and the regulating valve on the regulating pipeline is controlled according to the temperature. The flow rate of the circulating water return water entering the circulating water heat exchanger 3 is adjusted accordingly, thereby controlling the raw water temperature.

[0030] As a preferred solution of the present invention, the RO membrane separator 2 is connected to the product pure water collection tank 8 and the separation concentrated water collection tank 9 through pipelines.

[0031] The production method of stabilizing the water recovery rate of the RO membrane of this embodiment includes the following steps:

[0032] When the raw water temperature in the raw water tank 1 is ≤15°C, the raw water is transferred to the circulating water heat exchanger 3, where it exchanges heat with the circulating water return water, controlling the raw water temperature to ≤30°C, and then returns to the raw water tank 1;

[0033] After being pumped into the pre-processor 7 filter to remove mechanical and biological impurities, it is then pumped to the RO membrane separator 2 for membrane separation to obtain pure water. The water flow rate is monitored and the water production rate is required to be ≥90%.

[0034] When raw water and circulating return water exchange heat in the circulating water heat exchanger 3 , the flow rate of the circulating return water fed into the circulating water heat exchanger 3 is adjusted according to the temperature of the raw water returning to the raw water tank 1 from the circulating water heat exchanger 3 .

[0035] Under normal operating conditions, when the raw water temperature is 25°C ± 3°C, the designed maximum pure water yield is ≤ 66.7%; the unit's water production rate is 100% ± 5% of the designed capacity. When the temperature of the external raw water drops, the water production rate can decrease by 3% to 4% for every degree Celsius drop in temperature. By exchanging heat between the raw water and the circulating return water (30-50°C) to raise the raw water temperature to 25°C ± 3°C, the RO reverse osmosis membrane unit's water production rate can reach 100% ± 5% of the designed capacity. The reduction in the circulating return water temperature helps reduce the workload of the cooling tower.

[0036] The present invention is not limited to the above-mentioned optional implementation methods. Anyone can derive various other forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, any technical solution that falls within the scope defined by the claims of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A production system for stabilizing the water recovery rate of RO membrane, characterized by: The invention comprises a raw water tank (1), an RO membrane separator (2) and a circulating water heat exchanger (3); the outlet of the raw water tank (1) is connected to the RO membrane separator (2) through a pipeline; the external raw water is divided into two paths and respectively sent to the raw water tank (1) or the tube side inlet of the circulating water heat exchanger (3); the tube side outlet of the circulating water heat exchanger (3) is connected to the raw water tank (1) through a pipeline; the circulating water return is sent to the shell side inlet of the circulating water heat exchanger (3); and the shell side outlet of the circulating water heat exchanger (3) sends out the circulating water return.

2. A production system for stabilizing the water recovery rate of RO membrane according to claim 1, characterized in that: A circulating water cooling tower (4) is provided on the circulating water return pipeline, and the circulating water cooling tower (4) delivers circulating water.

3. The production system for stabilizing the water recovery rate of RO membrane according to claim 1, characterized in that: A regulating pipeline is connected between the pipeline before the circulating water returns to the circulating water heat exchanger (3) and the pipeline for the circulating water returns to the circulating water heat exchanger (3), and a bypass flow regulating valve (5) is connected to the regulating pipeline.

4. A production system for stabilizing the water recovery rate of RO membrane according to claim 3, characterized in that: A temperature indicator (6) is connected to the pipeline between the pipe outlet of the circulating water heat exchanger (3) and the raw water tank (1), and the temperature indicator (6) is signal-connected to the bypass flow regulating valve (5).

5. The production system for stabilizing the water recovery rate of RO membrane according to claim 1, characterized in that: A pre-processor (7) is connected to the pipeline between the raw water tank (1) and the RO membrane separator (2).

6. The production system for stabilizing the water recovery rate of RO membrane according to claim 1, characterized in that: The RO membrane separator (2) is connected to a product pure water collection tank (8) and a separation concentrated water collection tank (9) through pipelines.

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