Chemical cleaning tank for seawater desalination reverse osmosis membrane

Abstract

The chemical cleaning tank comprises a cleaning tank body, the cleaning tank body is made of carbon steel, the outer surface of the cleaning tank body is provided with a heat preservation layer, the inner surface of the cleaning tank body is coated with a glass fiber reinforced plastic anti-corrosion layer, and the top of the cleaning tank body is provided with a flange, a liquid level meter flange and a manhole. A flange, a heating flange and a short pipe are arranged on the lower portion of the cleaning tank body, a pipeline support is arranged on the cleaning tank body, compared with an existing glass fiber reinforced plastic material, the chemical cleaning tank made of the carbon steel material has the advantages that carbon steel is large in hardness and high in strength, the carbon steel cleaning tank is large in mass and good in stability, and the vibration resistance of the chemical cleaning tank can be improved; a heat preservation layer is added on the outer surface of the cleaning tank to guarantee the heat preservation effect of the cleaning tank; the glass fiber reinforced plastic anti-corrosion layer is coated on the inner surface of the cleaning tank, so that the chemical cleaning tank made of carbon steel is effectively prevented from being corroded by chemical cleaning liquid medicine.

Description

Technical Field

[0001] The utility model belongs to the technical field of seawater desalination equipment, and in particular relates to a chemical cleaning tank for a seawater desalination reverse osmosis membrane. Background Art

[0002] Reverse osmosis, also known as reverse osmosis (RO), is a process that uses a certain pressure to separate the solvent in the solution through an osmotic membrane (or semi-permeable membrane). Because it is in the opposite direction of natural osmosis, it is called reverse osmosis. According to the different osmotic pressures of various materials, the reverse osmosis method can be used to achieve the purpose of separation, extraction, purification and concentration. In seawater desalination projects, the performance of reverse osmosis membranes is crucial. After long-term high-load operation of reverse osmosis membrane groups, chemical cleaning is required to restore their performance.

[0003] In a seawater desalination plant, the cycle process for chemical cleaning of the reverse osmosis membrane group is:

[0004]

[0005] In the current large-scale desalination plants, in the above-mentioned cleaning process, the chemical cleaning tank of the reverse osmosis membrane is usually made of glass fiber reinforced plastics for the requirements of corrosion resistance and heat preservation. However, in large-scale desalination plants, the water production scale of a set of reverse osmosis membrane groups is usually large (such as a single set of membrane groups producing 20,000 tons / day), and the use of chemical cleaning liquid for a single set of reverse osmosis membrane groups is also very large. The cleaning liquid is configured in the chemical cleaning tank, which determines that the chemical cleaning tank must have a relatively large volume. In practical applications, the membrane group cleaning return water has high potential energy, the pipeline is complex, and there are many water hammers, which have a large impact on the tank body and cause the tank body to vibrate. Therefore, when the reverse osmosis membrane group is chemically cleaned, only a lower cleaning flow rate can be used. When the cleaning flow rate is limited, it is necessary to add cleaning liquid to the chemical cleaning tank in order to dissolve more metal oxides, pollutants, etc. in the reverse osmosis membrane group into the cleaning liquid, thereby improving the cleaning effect of the reverse osmosis membrane group, thereby increasing the amount of cleaning liquid and the amount of flushing water, resulting in an increase in cleaning costs. Utility Model Content

[0006] In order to overcome the above-mentioned technical problems existing in the prior art, the purpose of the utility model is to provide a chemical cleaning tank for seawater desalination reverse osmosis membrane, improve the vibration resistance of the chemical cleaning tank, thereby increasing the cleaning flow rate; reduce the volume of the chemical cleaning tank, save the amount of medicine and water, and reduce the cleaning cost.

[0007] The utility model provides a chemical cleaning tank for a seawater desalination reverse osmosis membrane, comprising a cleaning tank body, the cleaning tank body being made of carbon steel, the outer surface of the cleaning tank body being provided with a heat preservation layer, the inner surface of the cleaning tank body being coated with an anti-corrosion layer, the top of the cleaning tank body being provided with a flange, a liquid level gauge flange and a manhole, the lower part of the cleaning tank body being provided with a flange, a heating flange and a short pipe, and the cleaning tank body being provided with a pipeline bracket.

[0008] The insulation layer is made of nitrile rubber and has a thickness of 30 mm.

[0009] The anti-corrosion layer is lined with glass fiber reinforced plastic anti-corrosion material.

[0010] The height of the cleaning tank body is 6.5m.

[0011] The pipeline supports are provided in no less than 3 groups, the number of pipeline supports in each group is equal, and the pipeline supports are arranged equidistantly up and down along the outer surface of the cleaning tank body.

[0012] The cleaning tank body is provided with a plurality of flanges on the top thereof, and the flanges have different diameters.

[0013] The heating flanges are provided with two in parallel at the upper and lower parts.

[0014] The manhole has a diameter of 500 mm.

[0015] The chemical cleaning tank for seawater desalination reverse osmosis membrane provided by the utility model has the beneficial effect that, compared with the existing glass fiber reinforced plastic material, the carbon steel chemical cleaning tank has high hardness and high strength, the carbon steel cleaning tank has large mass and good stability, and the vibration resistance of the chemical cleaning tank can be improved; an insulation layer is added to the outer surface of the cleaning tank to ensure the thermal insulation effect of the cleaning tank; a glass fiber reinforced plastic anti-corrosion layer is coated on the inner surface of the cleaning tank to effectively prevent the chemical cleaning liquid from corroding the carbon steel chemical cleaning tank, the height of the cleaning tank with the same diameter is reduced from 10m to 6.5m, the amount of liquid that can be configured in the cleaning tank is reduced, and after the problem of tank body vibration is solved, the cleaning flow rate of the reverse osmosis membrane group can be increased from 1400m3 / h to 1900m3 / h. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a top view structural schematic diagram of the present application;

[0017] Figure 2 yes Figure 1 AA section view;

[0018] Figure 3 yes Figure 1 BB cross-sectional view;

[0019] Figure 4 yes Figure 1 CC section view;

[0020] Figure 5 It is a schematic diagram of the cross-sectional structure of the tank wall of the cleaning tank body.

[0021] Note in the figure:

[0022] 1. Insulation layer; 2. Cleaning tank body; 3. FRP anti-corrosion layer; 4. Liquid level gauge flange; 5. Manhole; 6. Pipe support; 7. Heating flange; 8. Short pipe; 9. Flange A; 10. Flange B; 11. Flange C; 12. Flange D; 13. Flange E. DETAILED DESCRIPTION

[0023] The following describes a chemical cleaning tank for performing detailed seawater desalination reverse osmosis membrane provided by the utility model in combination with an embodiment with reference to the accompanying drawings.

[0024] Example

[0025] Reference Figure 1-Figure 5 A chemical cleaning tank for a seawater desalination reverse osmosis membrane in this embodiment includes a cleaning tank body 2, the cleaning tank body 2 is made of carbon steel, the outer surface of the cleaning tank body 2 has an insulation layer 1, the inner surface of the cleaning tank body 2 is coated with an anti-corrosion layer 3, the top of the cleaning tank body 2 is provided with a flange, a liquid level gauge flange 4 and a manhole 5, the lower part of the cleaning tank body 2 is provided with a flange C11, a flange B10, a heating flange 7 and a short pipe 8, and the cleaning tank body 2 is provided with a pipe bracket 6.

[0026] The insulation layer 1 is made of nitrile rubber, and the thickness of the insulation layer 1 is 30 mm.

[0027] The anti-corrosion layer 3 is lined with glass fiber reinforced plastic anti-corrosion material.

[0028] The height of the cleaning tank body 2 is 6.5 m.

[0029] The pipe supports 6 are provided in no less than 3 groups, the number of pipe supports in each group is equal, and the pipe supports are arranged equidistantly up and down along the outer surface of the cleaning tank body.

[0030] The cleaning tank body is provided with several flanges on the top, including flange A9, flange D12, and flange E13, and the diameters are different.

[0031] The heating flanges are provided with two in parallel at the upper and lower parts.

[0032] The manhole 5 has a diameter of 500 mm.

[0033] A reverse osmosis membrane group with a water production capacity of 20,000 tons / day was selected from Qingdao Water Affairs Bishuiyuan Seawater Desalination Co., Ltd., and chemical cleaning was performed on it before and after the modification of the reverse osmosis chemical cleaning system. The operating conditions of the reverse osmosis membrane group were the same before the chemical cleaning, and the operating pressure difference of the membrane group reached the chemical cleaning standard. The chemical concentrations of the two chemical cleanings were the same, but the cleaning flow rates were different. The cleaning flow rate of the original chemical cleaning system was 1400m3 / h, and the cleaning flow rate of the modified chemical cleaning system was 1900m3 / h. The operating data of the two reverse osmosis membrane groups under the same operating pressure conditions before and after the chemical cleaning were recorded separately to compare the cleaning effects. The comparison results are shown in Table 1:

[0034] Table 1

[0035]

[0036] It can be seen from Table 1 that compared with the original reverse osmosis chemical cleaning system, the modified reverse osmosis chemical cleaning system has a lower operating pressure difference, higher water production flow rate and desalination rate, and better overall chemical cleaning effect under the same operating pressure conditions.

[0037] Through the transformation of the reverse osmosis chemical cleaning system, the vibration resistance of the reverse osmosis chemical cleaning tank can be effectively improved, the entire cleaning system can be protected, and its service life can be extended. The height of the cleaning tank with the same diameter is reduced, and the amount of liquid that can be configured in the cleaning tank is reduced. After the problem of tank vibration is solved, the cleaning flow rate of the reverse osmosis membrane group can be increased to 1900m3 / h. Experiments have proved that reducing the amount of liquid used for chemical cleaning and increasing the cleaning flow rate can achieve better cleaning effects. The total amount of liquid configured in the chemical cleaning tank is reduced. Under the same agent concentration conditions, the amount of medicine used will also be reduced, and the fresh water used to configure the cleaning liquid will also be reduced.

Claims

1. A chemical cleaning tank for seawater desalination reverse osmosis membrane, characterized in that: It includes a cleaning tank body, which is made of carbon steel. The outer surface of the cleaning tank body has an insulation layer, the inner surface of the cleaning tank body is coated with an anti-corrosion layer, the top of the cleaning tank body is provided with a flange, a liquid level gauge flange and a manhole, the lower part of the cleaning tank body is provided with a flange, a heating flange and a short pipe, and the cleaning tank body is provided with a pipe bracket.

2. The chemical cleaning tank for seawater desalination reverse osmosis membrane according to claim 1, characterized in that: The insulation layer is made of nitrile rubber and has a thickness of 30 mm.

3. The chemical cleaning tank for seawater desalination reverse osmosis membrane according to claim 1, characterized in that: The anti-corrosion layer is lined with glass fiber reinforced plastic anti-corrosion material.

4. The chemical cleaning tank for seawater desalination reverse osmosis membrane according to claim 1, characterized in that: The height of the cleaning tank body is 6.5m.

5. The chemical cleaning tank for seawater desalination reverse osmosis membrane according to claim 1, characterized in that: The pipeline supports are provided in no less than 3 groups, the number of pipeline supports in each group is equal, and the pipeline supports are arranged equidistantly up and down along the outer surface of the cleaning tank body.

6. The chemical cleaning tank for seawater desalination reverse osmosis membrane according to claim 1, characterized in that: The cleaning tank body is provided with a plurality of flanges on the top thereof, and the flanges have different diameters.

7. The chemical cleaning tank for seawater desalination reverse osmosis membrane according to claim 1, characterized in that: The heating flanges are provided with two in parallel at the upper and lower parts.

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