Device for treating concentrated seawater by coupling reverse osmosis with pervaporation

Abstract

The utility model discloses a device for treating concentrated seawater by coupling reverse osmosis with pervaporation. The device comprises a reverse osmosis unit and a pervaporation unit, the reverse osmosis unit comprises a raw water tank, a raw water pump, a filter, a high-pressure pump and a reverse osmosis membrane assembly; the pervaporation unit comprises a reverse osmosis concentrated water tank, a water suction pump, a pervaporation membrane assembly, a condenser, a fresh water tank and a vacuum pump. Concentrated seawater produced by the reverse osmosis unit can be collected by the reverse osmosis concentrated water tank, and the concentrated seawater can be further treated by the pervaporation unit to produce desalted water meeting the water quality requirement. By utilizing the coupling device, on one hand, the treatment capacity of concentrated seawater is reduced, and on the other hand, the recovery rate of desalinated water is improved, so that'minimum 'discharge in a real sense is achieved.

Description

Technical Field

[0001] The utility model relates to the field of seawater desalination, in particular to a device for treating concentrated seawater by reverse osmosis coupled pervaporation. Technical Background

[0002] Due to climate change and increased human activities, the global shortage of fresh water resources continues to worsen. In the past few decades, in order to meet the demand for fresh water, seawater desalination technology has developed rapidly. Reverse osmosis technology is a common technology for seawater desalination. It has the advantages of modular design, low energy consumption, and simple operation. However, since reverse osmosis technology desalinates seawater by applying external driving force to seawater to overcome osmotic pressure and allow water molecules to pass through the membrane in a reverse osmosis process, the energy required for reverse osmosis to desalinate seawater is directly related to the concentration of seawater. Therefore, when reverse osmosis is used to osmose fresh water from seawater, the higher the concentration of seawater, the higher the energy consumption required. Therefore, due to cost considerations, reverse osmosis technology will produce a large amount of concentrated seawater when desalinating seawater. Therefore, it is urgent to develop a seawater desalination system that reduces the amount of concentrated seawater to be processed and improves the recovery rate of desalinated water.

[0003] The country attaches great importance to the dual carbon goals, requiring the reduction of energy consumption in seawater desalination and the reduction of carbon emissions in the process of seawater desalination. The treatment of concentrated seawater is an important link in the process of seawater desalination. Reducing the amount of concentrated seawater treated helps to reduce the pollution of the desalination process to the environment. Secondly, concentrated seawater contains rich salt and other valuable resources. Reducing the amount of concentrated seawater treated can promote the recycling of resources. Therefore, reducing the amount of concentrated seawater treated and increasing the freshwater recovery rate of seawater desalination can not only improve economic benefits, but also have important significance for promoting the realization of the country's dual carbon goals. Utility Model Content

[0004] The purpose of the utility model is to provide a device for treating concentrated seawater by reverse osmosis coupled with pervaporation, so as to solve the problems of large concentrated seawater volume and low utilization rate in the prior art. The utility model adopts the following technical solutions:

[0005] A device for treating concentrated seawater by reverse osmosis coupled with pervaporation comprises a reverse osmosis unit and a pervaporation unit. The reverse osmosis unit is provided with a seawater impurity removal inlet and a concentrated seawater outlet; the pervaporation unit is provided with a concentrated seawater inlet and a desalinated water outlet.

[0006] Furthermore, the water inlet end of the raw water pump in the reverse osmosis unit is connected to the water outlet end of the raw water tank through an inlet pipe, the water outlet end of the raw water pump is connected to the inlet end of the filter through an outlet pipe, the water outlet end of the filter is connected to the inlet end of the high-pressure pump through an outlet pipe, the water outlet end of the high-pressure pump is connected to the inlet end of the reverse osmosis membrane assembly through an outlet pipe, and the concentrated seawater outlet end of the reverse osmosis membrane assembly is connected to the inlet end of the reverse osmosis concentrated water tank through a concentrated seawater drain pipe.

[0007] Furthermore, the water inlet end of the reverse osmosis concentrated water tank in the pervaporation unit is connected to the water outlet end of the reverse osmosis membrane assembly through a concentrated seawater drain pipe, the water outlet end of the reverse osmosis concentrated water tank is connected to the input end of a water pump through an outlet pipe, the output end of the water pump is connected to the water inlet end of the pervaporation membrane assembly through a drain pipe, the permeation end of the pervaporation membrane assembly is connected to the inlet end of a condenser through a vaporization pipe, the outlet end of the condenser is connected to the inlet end of a fresh water tank through a drain pipe, and the outlet end of the fresh water tank is connected to the interface end of a vacuum pump.

[0008] Furthermore, a flow regulating valve is provided on the output end drain pipe of the water pump in the pervaporation unit, and the flow regulating valve is used to control the water output in the reverse osmosis concentrated water tank. A flow meter is provided on the outlet end drain pipe of the condenser in the pervaporation unit, and the flow meter is used to detect the fresh water output.

[0009] Through the above technical solution, the utility model has the following beneficial effects:

[0010] The reverse osmosis concentrated seawater produced by the reverse osmosis unit can be collected by using a reverse osmosis concentrated water tank, and the concentrated seawater can be further processed by a pervaporation unit, which can not only reduce the processing volume of concentrated seawater, but also improve the recovery rate of desalinated water. This is in line with the international trend of energy conservation, emission reduction and environmental protection.

[0011] The salt concentration of reverse osmosis concentrated seawater has almost no effect on the pervaporation salt retention rate, which is always maintained above 99.9%. The device has a compact structure, small footprint, simple process flow, and modular design. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic structural diagram of a reverse osmosis coupled pervaporation device for treating concentrated seawater according to the utility model.

[0013] The reference numerals are as follows:

[0014] 1 raw water tank, 2 raw water pump, 3 filter, 4 high pressure pump, 5 reverse osmosis membrane assembly, 6 reverse osmosis concentrated water tank, 7 water pump, 8 pervaporation membrane assembly, 9 condenser, 10 fresh water tank, 11 vacuum pump, 12 reverse osmosis unit, 13 pervaporation unit, 14 flow regulating valve, 15 flow meter. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0016] As described in the background technology section, the reverse osmosis device in the prior art has the problem of low utilization rate of concentrated seawater. In order to solve this problem, the utility model provides a reverse osmosis coupled pervaporation device for treating concentrated seawater, such as Figure 1 As shown, the device includes a reverse osmosis unit 12 and a pervaporation unit 13; the reverse osmosis unit 12 is provided with a seawater impurity removal inlet and a concentrated seawater outlet; the pervaporation unit 13 is provided with a concentrated seawater inlet and a desalinated water outlet.

[0017] The water inlet end of the raw water pump 2 in the reverse osmosis unit 12 is connected to the water outlet end of the raw water tank 1 through an inlet pipe, the water outlet end of the raw water pump 2 is connected to the inlet end of the filter 3 through an outlet pipe, the water outlet end of the filter 3 is connected to the inlet end of the high-pressure pump 4 through an outlet pipe, the water outlet end of the high-pressure pump 4 is connected to the inlet end of the reverse osmosis membrane assembly 5 through an outlet pipe, and the concentrated seawater outlet end of the reverse osmosis membrane assembly 5 is connected to the inlet end of the reverse osmosis concentrated water tank 6 through a concentrated seawater drain pipe.

[0018] The water inlet end of the reverse osmosis concentrated water tank 6 in the pervaporation unit 13 is connected to the water outlet end of the reverse osmosis membrane assembly 5 through a concentrated seawater drain pipe, the water outlet end of the reverse osmosis concentrated water tank 6 is connected to the input end of the pump 7 through the outlet pipe, the output end of the pump 7 is connected to the water inlet end of the pervaporation membrane assembly 8 through a drain pipe, the permeation end of the pervaporation membrane assembly 8 is connected to the inlet end of the condenser 9 through a vaporization pipe, the outlet end of the condenser 9 is connected to the inlet end of the fresh water tank 10 through a drain pipe, and the outlet end of the fresh water tank 10 is connected to the interface end of the vacuum pump 11.

[0019] Specifically, the seawater is transported from the raw water tank 1 to the filter 3 through the raw water pump 2. After the seawater is pre-treated by the filter 3, the seawater is transported to the reverse osmosis membrane assembly 5 under the action of the high-pressure pump 4. Under the strong pressure drive, the seawater is separated into concentrated seawater and desalinated water. The concentrated seawater is then transported to the reverse osmosis concentrated water tank 6. Under the action of the pump 7, the concentrated seawater is transported to the pervaporation membrane assembly 8. The pervaporation membrane in the pervaporation membrane assembly 8 is a high-flux dense hydrophilic membrane. The membrane performs pervaporation on the reverse osmosis concentrated seawater, so that an osmotic pressure difference is generated on both sides of the pervaporation membrane during pervaporation, so that solutes such as inorganic salts in the reverse osmosis concentrated seawater are retained by the high-flux dense hydrophilic membrane, and water molecules in the reverse osmosis concentrated seawater pass through the high-flux dense hydrophilic membrane after desorption and vaporization, and are liquefied into desalinated water in the condenser 9. Under the action of the vacuum pump 11, the desalinated water in the condenser 9 is transported to the fresh water tank 10, thereby reducing the processing volume of concentrated seawater and improving the recovery rate of desalinated water.

[0020] Furthermore, a flow regulating valve 14 is provided on the output end drain pipe of the water pump 7 in the pervaporation unit 13, and the flow regulating valve 14 is used to control the water output in the reverse osmosis concentrated water tank 6. A flow meter 15 is provided on the outlet end drain pipe of the condenser 9 in the pervaporation unit 13, and the flow meter 15 is used to detect the fresh water output.

Claims

1. A device for treating concentrated seawater by reverse osmosis coupled with pervaporation, characterized in that: The invention comprises a reverse osmosis unit (12) and a pervaporation unit (13), wherein the water inlet of the raw water pump (2) in the reverse osmosis unit (12) is connected to the water outlet of the raw water tank (1) through a water inlet pipe, the water outlet of the raw water pump (2) is connected to the inlet of the filter (3) through a water outlet pipe, the water outlet of the filter (3) is connected to the inlet of the high-pressure pump (4) through a water outlet pipe, the water outlet of the high-pressure pump (4) is connected to the inlet of the reverse osmosis membrane assembly (5) through a water outlet pipe, the concentrated seawater outlet of the reverse osmosis membrane assembly (5) is connected to the inlet of the reverse osmosis concentrated water tank through a concentrated seawater drainage pipe, and the water inlet of the reverse osmosis concentrated water tank (6) in the pervaporation unit (13) is connected to the concentrated seawater drainage pipe through a concentrated seawater drainage pipe. At the water outlet of the reverse osmosis membrane assembly (5), the water outlet of the reverse osmosis concentrated water tank (6) is connected to the input end of a water pump (7) through a water outlet pipe, the output end of the water pump (7) is connected to the water inlet end of a pervaporation membrane assembly (8) through a drain pipe, the permeation end of the pervaporation membrane assembly (8) is connected to the inlet end of a condenser (9) through a vaporization pipe, the outlet end of the condenser (9) is connected to the inlet end of a fresh water tank (10) through a drain pipe, the outlet end of the fresh water tank (10) is connected to the interface end of a vacuum pump (11), the reverse osmosis unit (12) is provided with a seawater impurity removal inlet and a concentrated seawater outlet, and the pervaporation unit (13) is provided with a concentrated seawater inlet and a desalinated water outlet.

2. The device for treating concentrated seawater by reverse osmosis coupled pervaporation according to claim 1, characterized in that: A flow regulating valve (14) is provided on the drainage pipe at the output end of the water pump (7) in the pervaporation unit (13), and the flow regulating valve (14) is used to control the water output from the reverse osmosis concentrated water tank (6). A flow meter (15) is provided on the drainage pipe at the outlet end of the condenser (9) in the pervaporation unit (13), and the flow meter (15) is used to detect the output of fresh water.

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