A seawater desalination water conditioning system and conditioning method

Abstract

The present invention belongs to the field of seawater desalination, and specifically relates to a seawater desalination water conditioning system and a conditioning method. The seawater desalination water conditioning system includes a carbon dioxide dosing device and a conditioning and filtering device. The carbon dioxide dosing device is used to dissolve carbon dioxide in the seawater desalinated water to achieve precise dosing of carbon dioxide. The conditioning and filtering device is used to perform conditioning treatment on the seawater desalinated water dissolved with carbon dioxide. The conditioning and filtering device includes a conditioning filter, and the conditioning filter sequentially includes a quartz sand filling layer and a natural mineralization material filling layer from bottom to top. The natural mineralization material includes zeolite and calcined ichthyolite, and the mass ratio of zeolite to ichthyolite is 1:3 - 1:5. In the seawater desalination water conditioning system of the present invention, the conditioning and filtering device has stronger shock load resistance, the natural mineralization material filling layer is easy to backwash, which can reduce the backwash water consumption, and the conditioning effect of the conditioning and filtering device is good. After the conditioning treatment, the seawater desalinated water can meet the national drinking water standard.

Description

Technical Field

[0001] The present invention relates to the technical field of seawater desalination, and particularly to a seawater desalination water conditioning system and a conditioning method. Background Art

[0002] Seawater desalination technology can remove most of the dissolved salts in seawater through technologies such as reverse osmosis, so that the salt content in the obtained seawater desalination water is extremely low. However, the seawater desalination water used as domestic drinking water is tasteless, has a poor taste, and lacks essential minerals for the human body, such as Ca 2+ and Mg 2+ etc. In addition, the water quality of seawater desalination water is unstable, has strong corrosiveness and erosiveness, and has a relatively serious corrosive effect on metal pipelines in particular. When seawater desalination water is supplied alone or mixed with other water sources, it may cause corrosion of the pipe network of the water delivery system, which will not only shorten the service life of the equipment, but also cause the phenomenon of "red water", seriously affecting normal use.

[0003] The prior art generally performs conditioning treatment on seawater desalination water to adjust the pH, alkalinity and hardness of the seawater desalination water, so as to prevent corrosion of the pipe network of its water delivery system and be beneficial to human health. The current seawater desalination water conditioning methods include the chemical addition method, the mixing method with other water sources, and the ore dissolution method, etc. Among them, the ore dissolution method is currently the simplest and most widely used seawater desalination water conditioning method. The commonly used ore in the ore dissolution method is food-grade limestone. However, the food-grade limestone has a low anti-impact load capacity. In the case of a sudden increase in the treated water volume, the effluent water quality may not meet the standards, and the backwashing efficiency is low, resulting in a large amount of backwashing water consumption.

[0004] Therefore, it is necessary to provide a seawater desalination water conditioning system and method with stronger anti-impact load capacity and higher backwashing efficiency. Summary of the Invention

[0005] (I) Technical Problems to be Solved

[0006] In view of the above technical problems, the present invention provides a seawater desalination water conditioning system and a conditioning method, which can improve the anti-impact load capacity, improve the backwashing efficiency, and reduce the water consumption for backwashing.

[0007] (II) Technical Solutions

[0008] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0009] In the first aspect, the present invention provides a seawater desalination water conditioning system, including a carbon dioxide dosing device and a conditioning filtration device;

[0010] The carbon dioxide dosing device is used to dissolve carbon dioxide in the desalinated seawater;

[0011] The conditioning and filtering device is used to condition the desalinated seawater dissolved with carbon dioxide. The conditioning and filtering device includes a conditioning filter, and the conditioning filter sequentially includes a quartz sand filling layer and a natural mineralization material filling layer from bottom to top;

[0012] In the natural mineralization material filling layer, the natural mineralization material includes zeolite and calcined ichthyolite. The mass ratio of zeolite to ichthyolite is 1:3 - 1:5.

[0013] For the desalinated seawater conditioning system as described above, preferably, the calcination temperature of the ichthyolite is 400 - 600 °C, and the calcination time is 1 - 2 h.

[0014] For the desalinated seawater conditioning system as described above, preferably, the thickness of the quartz sand filling layer is 0.15 - 0.25 m, and the particle size of the quartz sand in the quartz sand filling layer is 2.5 - 5.0 mm; the thickness of the natural mineralization material filling layer is 1.8 - 2.2 m, and the particle sizes of the zeolite and the ichthyolite are 0.5 - 1.5 mm. The particle sizes of the above-mentioned quartz sand, zeolite, and ichthyolite can be selected from any value within their respective defined ranges, or can be distributed throughout the particle size range.

[0015] For the desalinated seawater conditioning system as described above, preferably, the carbon dioxide dosing device includes a reverse osmosis product water bypass booster device and a carbon dioxide storage device, a carbon dioxide conversion device, and a carbon dioxide dosing and mixing device connected in sequence;

[0016] Both ends of the reverse osmosis product water bypass booster device are respectively connected to the desalinated seawater production water bypass pipeline and the carbon dioxide dosing and mixing device.

[0017] For the desalinated seawater conditioning system as described above, preferably, the reverse osmosis product water bypass booster device includes a first booster pump, the carbon dioxide storage device includes a carbon dioxide storage tank, and the carbon dioxide conversion device includes an evaporator and a pressure reducing and stabilizing component;

[0018] The other end of the carbon dioxide dosing and mixing device is connected to the desalinated seawater production main pipeline, and the desalinated seawater production main pipeline is also connected to the conditioning filter.

[0019] For the desalinated seawater conditioning system as described above, preferably, the conditioning and filtering device further includes a water and gas distribution layer arranged below the quartz sand filling layer;

[0020] The water and gas distribution layer includes a filter plate and a plurality of water distribution structures arranged on the filter plate.

[0021] The seawater desalination water conditioning system as described above, preferably, the conditioning filter further includes a natural mineral material dosing device located above the natural mineral material filling layer;

[0022] The natural mineral material dosing device includes a storage bin and a feeding pipe connected to the storage bin. The storage bin stores natural mineral materials, and an automatic feeding port is also provided at the upper end of the storage bin.

[0023] The seawater desalination water conditioning system as described above, preferably, further includes an air-water combined backwashing device connected to the conditioning filter;

[0024] The air-water combined backwashing device includes a backwashing fan and a backwashing water booster pump.

[0025] In a second aspect, the present invention also provides a seawater desalination water conditioning method using the above-mentioned seawater desalination water conditioning system, including the following steps:

[0026] S1: Adding carbon dioxide to the seawater desalination water through a carbon dioxide dosing device to obtain seawater desalination water dissolved with carbon dioxide;

[0027] S2: The seawater desalination water dissolved with carbon dioxide sequentially passes through the quartz sand filling layer and the natural mineral material filling layer of the conditioning filter for filtration treatment and conditioning treatment to obtain drinking water meeting the drinking standard.

[0028] In the seawater desalination water conditioning method as described above, preferably, in step S1, carbon dioxide is added to the seawater desalination water from the seawater desalination water production bypass pipeline through a carbon dioxide dosing device to obtain seawater desalination water dissolved with carbon dioxide;

[0029] In step S2, the seawater desalination water dissolved with carbon dioxide enters the main pipeline of the seawater desalination water production, and then sequentially passes through the quartz sand filling layer and the natural mineral material filling layer of the conditioning filter for filtration treatment and conditioning treatment to obtain drinking water meeting the drinking standard.

[0030] (III) Beneficial effects

[0031] The seawater desalination water conditioning system of the present invention uses zeolite and calcined ichthyolite as natural mineral materials. Compared with existing chemical agents, zeolite and ichthyolite have stronger anti-shock load capacity as mineralization materials. Even when the water inflow suddenly increases to 120% of the normal treatment flow rate, the effluent water quality can still meet the standards stably. This high stability and adaptability provide a guarantee for the wide application of the system under different conditions.

[0032] The backwashing of the natural mineral material filling layer composed of zeolite and calcined ichthyolite is more efficient, which can greatly reduce the backwashing water consumption, effectively reduce the water treatment burden, and improve the water resource utilization efficiency.

[0033] Zeolite and calcined ichthyolite contain various mineral components. The surface of the calcined ichthyolite becomes porous, which is conducive to the entry of water molecules and enhances the dissolution of minerals. Due to its own structural characteristics and the imbalance of coordination bonds, zeolite combined with the calcined ichthyolite can balance the ion concentration in the water body, effectively increase the hardness of the water, adjust the too low pH value of the desalinated seawater, and make it reach the suitable range for drinking. At the same time, zeolite and the calcined ichthyolite can also supplement an appropriate amount of alkaline substances to help stabilize the alkalinity in the water quality and prevent pipeline corrosion. After the conditioning treatment by the conditioning filtration equipment, the pH value, alkalinity, hardness, etc. of the desalinated seawater can all meet the requirements of the national drinking water standard, showing a good conditioning effect. Description of the Drawings

[0034] Figure 1 It is a schematic diagram of the overall structure of the desalinated seawater conditioning system in the present invention;

[0035] Figure 2 It is a flow chart of carbon dioxide dosing in the present invention;

[0036] Figure 3 It is a flow chart of the conditioning filtration treatment in the present invention.

[0037]

Description of the Reference Numerals

[0038] 1: Carbon dioxide storage tank; 2: Evaporator; 3: First booster pump; 4: Carbon dioxide dosing and mixing device; 5: Backwash water booster pump; 6: Conditioning filter; 7: Backwash fan; 8: Product water tank; 9: Feed water pump; 10: Ultraviolet sterilizer; 11: First desalinated seawater inlet; 12: Second desalinated seawater inlet; 13: Third desalinated seawater inlet; 14: Conditioned water outlet. Detailed Embodiments

[0039] For better explaining the present invention for easy understanding, the present invention will be described in detail below in conjunction with the drawings and specific embodiments.

[0040] As Figures 1 - 3 shown, the present invention provides a desalinated seawater conditioning system, including a carbon dioxide dosing device and a conditioning filtration device. The carbon dioxide dosing device is used to dissolve carbon dioxide in the desalinated seawater and accurately dose the carbon dioxide into the desalinated seawater. The conditioning filtration device is used to perform conditioning treatment on the desalinated seawater dissolved with carbon dioxide. The conditioning filtration device includes a conditioning filter 6, and the conditioning filter 6 successively includes a quartz sand filling layer and a natural mineralization material filling layer from bottom to top. In the natural mineralization material filling layer, the natural mineralization materials include zeolite and calcined ichthyolite, and the mass ratio of zeolite to ichthyolite is 1:3 - 1:5.

[0041] In the present invention, zeolite and calcined ichthyolite are used as natural mineralization materials. Compared with existing chemical agents, zeolite and ichthyolite have stronger anti-shock load capacity as mineralization materials. Even when the influent water volume suddenly increases to 120% of the normal treatment flow rate, the effluent water quality still meets the standards stably. This high stability and adaptability provide guarantee for the wide application of the system under different conditions.

[0042] The backwashing of the natural mineralization material filling layer composed of zeolite and calcined ichthyolite is more efficient, which can greatly reduce the water consumption of backwashing, effectively reduce the water treatment burden, and improve the water resource utilization efficiency.

[0043] The invention patent application with the publication number CN111392934A believes that the precipitation amounts of various mineral elements in ichthyolite are not prominent and it is not suitable for the mineralization treatment of desalinated seawater. However, through long-term research and experiments, the researchers of the present invention found that ichthyolite can be calcined to improve its dissolution property. Ichthyolite contains various mineral components. After calcination, the surface of ichthyolite becomes porous, which is conducive to the entry of water molecules, and the dissolution property of the minerals therein is enhanced. In addition to calcination, the present invention also uses a mixture of ichthyolite and zeolite as filter media. Due to the unbalanced coordination bonds and its own structural characteristics, zeolite combined with calcined ichthyolite can balance the ion concentration in water, effectively increase the hardness of water, adjust the too low pH value of desalinated seawater, and make it reach the suitable drinking range. At the same time, zeolite and calcined ichthyolite can also supplement appropriate alkaline substances to help stabilize the alkalinity in water quality and prevent pipeline corrosion. After the conditioning treatment by the conditioning filtration equipment, the pH value, alkalinity, hardness, etc. of desalinated seawater can all meet the requirements of the national drinking water standard, and have a good conditioning effect.

[0044] In the present invention, when zeolite and calcined ichthyolite are mixed at a mass ratio of 1:3 - 1:5, the conditioning effect on desalinated seawater is the best. If it exceeds this mass ratio range, or uncalcined ichthyolite is used, it may affect the conditioning effect.

[0045] It should be noted that the desalinated seawater in the present invention can be an aqueous solution obtained by treating seawater through methods such as reverse osmosis method, electrodialysis method, distillation method, and freeze separation method.

[0046] Preferably, in the present invention, the calcination temperature of ichthyolite is 400 - 600 °C, and the calcination time is 1 - 2 h. The thickness of the quartz sand filling layer is 0.15 - 0.25 m, the particle size of the quartz sand in the quartz sand filling layer is 2.5 - 5.0 mm, the thickness of the natural mineralization material filling layer is 1.8 - 2.2 m, and the particle size of zeolite and ichthyolite is 0.5 - 1.5 mm.

[0047] The carbon dioxide dosing equipment adds carbon dioxide to the seawater desalinated water. Carbon dioxide dissolves in water to form carbonic acid, which helps to increase the bicarbonate ions in the water and raise the alkalinity. In addition, carbonic acid can also promote the mineralization of natural mineral materials. Zeolite and calcined ichthyolite can better release trace elements beneficial to the human body, such as calcium, magnesium, silicic acid, strontium, molybdenum, zinc, selenium, etc. in the seawater desalinated water dissolved with carbon dioxide, improving the hardness and mineral content of the water body and further optimizing the water quality.

[0048] Preferably, the carbon dioxide dosing equipment includes a reverse osmosis product water bypass booster device and a carbon dioxide storage device, a carbon dioxide conversion device, and a carbon dioxide dosing and mixing device 4 connected in sequence. The two ends of the reverse osmosis product water bypass booster device are respectively connected to the seawater desalination product water bypass pipeline and the carbon dioxide dosing and mixing device 4. The above-mentioned devices can be connected and adjusted through relevant pipelines, valves and other components, and control instruments can also be set to monitor and control each process.

[0049] The carbon dioxide dosing equipment also includes relevant monitoring instruments such as pressure gauges, temperature gauges, pH meters, flow meters, etc., and a control module, etc.

[0050] The reverse osmosis product water bypass booster device specifically includes a first booster pump 3. The carbon dioxide storage device includes a carbon dioxide storage tank 1. The carbon dioxide conversion device includes an evaporator 2 and a pressure reducing and stabilizing component. The evaporator 2 is respectively connected to the carbon dioxide storage tank 1 and the pressure reducing and stabilizing component through pipelines and valves. The pressure reducing and stabilizing component is connected to the carbon dioxide dosing and mixing device 4. The carbon dioxide storage tank 1 can adopt a special vacuum-insulated low-temperature storage tank, and various valves and connectors for operation can be set to supply liquid to the vaporizer, and a pressure gauge, a liquid level gauge, etc. are provided to observe the pressure and liquid level in the tank, etc. In addition, safety devices can also be set in the inner and outer cylinders to ensure the safe use of users. The evaporator 2 can be an integrated evaporator 2 for converting low-temperature liquid CO 2 to high-pressure gaseous CO 2 . The other end of the carbon dioxide dosing and mixing device 4 is connected to the seawater desalination product water main pipeline, and the seawater desalination product water main pipeline is also connected to a conditioning filter 6.

[0051] Low-temperature liquid CO 2 is stored in the carbon dioxide storage device, and the liquid CO 2 can be converted into high-pressure gaseous CO 2 through a valve group and the evaporator 2. The high-pressure gaseous CO 2 is converted into low-pressure gaseous CO 2 through the pressure reducing and stabilizing component, and then the low-pressure gaseous CO 2 is quantitatively input into the carbon dioxide dosing and mixing device 4 through a regulating valve, a flow meter, a microporous dosing device, etc.

[0052] As Figure 2 shown, the desalinated water in the desalinated water bypass pipeline of seawater desalination enters the carbon dioxide dosing and mixing device 4 after being pressurized by the reverse osmosis product water bypass booster device. At the same time, low-pressure gaseous CO 2 also enters the carbon dioxide dosing and mixing device 4. Under the action of the carbon dioxide dosing and mixing device 4, CO 2 is fully mixed into the desalinated water from the desalinated water bypass pipeline of seawater desalination. The outlet water of the carbon dioxide dosing and mixing device 4, that is, the desalinated water dissolved with CO 2 is connected to the main pipeline of the desalinated water produced by seawater desalination. The desalinated water dissolved with CO 2 enters the conditioning filter 6 along with the desalinated water in the main product pipeline for conditioning treatment.

[0053] Preferably, the conditioning filtration equipment further includes a water-gas distribution layer arranged below the quartz sand filling layer and a natural mineralization material dosing device located above the natural mineralization material filling layer. The water-gas distribution layer includes a filter plate and a plurality of water distribution structures arranged on the filter plate. The water distribution structure can be a water distribution cap or the like. The natural mineralization material dosing device includes a storage bin and a feed pipe connected to the storage bin. The storage bin stores natural mineralization materials, and an automatic feeding port is also opened at the upper end of the storage bin. Similarly, the conditioning filtration equipment further includes relevant monitoring instruments such as pressure gauges, temperature gauges, pH meters, flow meters, etc. and a control module.

[0054] The main function of the conditioning filtration equipment is to dose CO 2The desalinated seawater is conditioned. The conditioning and filtering equipment includes a conditioning filter 6. After water / air enters from the bottom of the conditioning filter 6, the conditioning filter 6 can be sequentially divided into the following regions from bottom to top: a water / air distribution region, a quartz sand filling layer region, a natural mineralization material filling layer region, an upper layer of conditioned water rising and overflowing region, and a natural mineralization material feeding region. The water / air distribution region corresponds to the region where the water-gas distribution layer is located. The filter plate and multiple water distribution caps arranged on the filter plate can form a flat air / water distribution platform. The contact surfaces of the components of the water-gas distribution layer and its contact with the wall of the conditioning filter 6 need to be sealed with rubber lining. The quartz sand filling layer is directly filled on the water-gas distribution layer. The quartz sand can promote uniform air-water distribution, and can also remove tiny particulate matters in the water body, prevent fine impurities and sol substances from blocking the water distribution caps, and ensure smooth and uniform water distribution. The natural mineralization material filling layer is located above the quartz sand filling layer. The upper layer of conditioned water rising and overflowing region refers to the space between the natural mineralization material filling layer region and the conditioned water overflow channel where the water flow after conditioning treatment is restricted. The upper layer of conditioned water rising and overflowing region has a certain thickness, which can avoid the overflow of fine particles and impurities dissolved in zeolite and ichthyolite, and ensure that the effluent turbidity < 1 NTU. The natural mineralization material feeding region corresponds to the region where the natural mineralization material feeding device is located. The natural mineralization material stored in the storage bin can directly fall onto the natural mineralization material filling layer through the feeding pipe under the action of gravity to supplement the natural mineralization material. The natural mineralization material in the feeding pipe crosses the upper layer of conditioned water rising and overflowing region and directly reaches the surface of the natural mineralization material filling layer, so that even if the natural mineralization material falls, it will not cause turbidity of the water layer.

[0055] Further preferably, the conditioning and filtering equipment further includes a combined air-water backwashing equipment connected to the conditioning filter 6. The combined air-water backwashing equipment specifically includes a backwashing blower 7 and a backwashing water booster pump 5. The backwashing blower 7 can be a Roots blower. The combined air-water backwashing process can remove the impurities remaining in the conditioning filter 6 due to long-term operation to restore the pollutant interception capacity of the conditioning filter 6. As Figure 3 shown, the backwashing water of the combined air-water backwashing equipment comes from the desalinated seawater. According to the actual operation data, the combined air-water backwashing frequency of the conditioning and filtering equipment of the present invention is 2-3 times per year, with high backwashing efficiency and less water required for backwashing.

[0056] As Figures 1 - 3 shown, the desalinated seawater in the present invention enters different structures from multiple inlets for different treatments. Figure 1The directions indicated by the arrows are all the flow directions of the desalinated seawater and the conditioned water. Specifically, the desalinated seawater can enter the first booster pump 3 from the first desalinated seawater inlet 11 for boosting treatment; the desalinated seawater can enter the evaporator 2 from the second desalinated seawater inlet 12 to make initial contact with carbon dioxide; the desalinated seawater can also enter the conditioning filter 6 from the second desalinated seawater inlet 12, be mixed with the desalinated seawater dissolved with carbon dioxide, and undergo conditioning and filtering treatment in the conditioning filter 6; the desalinated seawater can also enter the backwash water booster pump 5 from the third desalinated seawater inlet 13 for backwashing.

[0057] The present invention also provides a method for conditioning desalinated seawater using the above desalinated seawater conditioning system, which includes the following steps:

[0058] S1: Add carbon dioxide to the desalinated seawater through a carbon dioxide dosing device to obtain desalinated seawater dissolved with carbon dioxide.

[0059] S2: The desalinated seawater dissolved with carbon dioxide sequentially passes through the quartz sand filling layer and the natural mineralization material filling layer of the conditioning filter 6 for filtering treatment and conditioning treatment to obtain drinking water meeting the drinking standard.

[0060] Preferably, in step S1, carbon dioxide is added to the desalinated seawater from the desalinated seawater production bypass pipeline through a carbon dioxide dosing device to obtain desalinated seawater dissolved with carbon dioxide. In step S2, the desalinated seawater dissolved with carbon dioxide enters the desalinated seawater production main pipeline, the water body enters from the bottom of the conditioning filter 6, sequentially passes through the water-gas distribution layer, the quartz sand filling layer and the natural mineralization material filling layer for filtering treatment and conditioning treatment, the treated water body enters the production water tank 8, and then passes through the feed water pump 9 to enter the ultraviolet sterilizer 10 for sterilization treatment to obtain drinking water meeting the drinking standard for users, and the obtained conditioned water / drinking water flows out from the conditioned water outlet 14.

[0061] The control module in the desalinated seawater conditioning system can be controlled by PLC, and a DCS communication interface is reserved at the PLC end to access the DCS auxiliary control water network. The start-stop control, operation status display, alarm and control under abnormal or accident conditions of the desalinated seawater conditioning system can all be completed at the local terminal and the auxiliary control network. The operation of the whole system realizes automatic control and reaches the level of unattended operation.

[0062] In order to further clarify the solution of the present invention and its technical progressiveness, the following is described in combination with specific embodiments and technical effects.

[0063] Embodiment 1

[0064] This embodiment provides a desalinated seawater conditioning system, which includes a carbon dioxide dosing device and a conditioning and filtering device.

[0065] The carbon dioxide dosing equipment includes a reverse osmosis product water bypass booster device, a carbon dioxide storage tank, a carbon dioxide conversion device, and a carbon dioxide dosing and mixing device connected in sequence, and also includes a pressure gauge, a temperature gauge, a pH meter, a flow meter, and a control module.

[0066] The reverse osmosis product water bypass booster device includes a first booster pump. Both ends of the first booster pump are connected to the seawater desalination product water bypass pipeline and the carbon dioxide dosing and mixing device through pipelines and valves respectively. The carbon dioxide storage device stores low-temperature liquid CO 2 , and the carbon dioxide conversion device includes an evaporator and a pressure reducing and stabilizing component. The evaporator is connected to the carbon dioxide storage tank and the pressure reducing and stabilizing component through pipelines and valves respectively, and the pressure reducing and stabilizing component is connected to the carbon dioxide dosing and mixing device. The water outlet of the carbon dioxide dosing and mixing device is connected to the main pipeline of the seawater desalination product water, and the main pipeline of the seawater desalination product water is also connected to the bottom water inlet of the conditioning filter.

[0067] The conditioning and filtering equipment includes a conditioning filter. The conditioning filter includes a gas-water distribution layer, a quartz sand filling layer, a natural mineralization material filling layer, and a natural mineralization material dosing device located above the natural mineralization material filling layer from bottom to top, and also includes relevant pressure gauges, temperature gauges, pH meters, flow meters and control modules. The conditioning filter is also connected to the air-water combined backwashing equipment. The air-water combined backwashing equipment includes a Roots blower and a backwash water booster pump. The water flow after conditioning treatment is restricted in the space between the natural mineralization material filling layer and the conditioning product water overflow channel. The gas-water distribution layer includes a filter plate and a plurality of water distribution caps arranged on the filter plate. The natural mineralization material dosing device includes a storage bin and a feeding pipe connected to the storage bin. The storage bin stores natural mineralization materials, and an automatic feeding port is also opened at the upper end of the storage bin.

[0068] The natural mineralization materials in the natural mineralization material filling layer include zeolite and calcined ichthyolite. The mass ratio of zeolite to ichthyolite is 1:4. The calcination temperature of ichthyolite is 500°C, and the calcination time is 2h. The thickness of the quartz sand filling layer is 0.2m, the average particle size of the quartz sand in the quartz sand filling layer is 4.2mm, the thickness of the natural mineralization material filling layer is 2.0m, and the average particle size of zeolite and ichthyolite is 1.0mm.

[0069] The above control modules are all controlled by PLC, and a DCS communication interface is reserved at the PLC end.

[0070] The desalinated seawater is conditioned by the seawater desalination water conditioning system of this embodiment. After conditioning, the water body enters the product water tank, and then passes through a feed water pump to enter an ultraviolet sterilizer for sterilization treatment to obtain drinking water. Before conditioning, the pH value of the desalinated seawater is 6.58, the total hardness is 6.52 mg / L, the total alkalinity is 4.03 mg / L, the total dissolved solids is 141.91 mg / L, the LSI is -2.53, the sodium content is 52.38 mg / L, the calcium content is 1.21 mg / L, the magnesium content is 0.85 mg / L, the metasilicic acid content is <1 mg / L, and the strontium content is <0.05 mg / L.

[0071] The pH value of the drinking water obtained by conditioning in this embodiment is 7.98, the total hardness is 191.91 mg / L, the total alkalinity is 62.33 mg / L, the total dissolved solids is 382.53 mg / L, the LSI is 0.05, the sodium content is 52.37 mg / L, the calcium content is 56.68 mg / L, the magnesium content is 12.23 mg / L, the metasilicic acid content is 5.3 mg / L, the strontium content is 0.28 mg / L, and the turbidity is <1 NTU.

[0072] Example 2

[0073] This embodiment provides a seawater desalination water conditioning system, which is different from that of Example 1 in that the mass ratio of zeolite to ichthyolite in the natural mineralization material is 1:3, the calcination temperature of ichthyolite is 600 °C, and the calcination time is 1 h. The thickness of the quartz sand filling layer is 0.15 m, the average particle size of the quartz sand in the quartz sand filling layer is 2.5 mm, the thickness of the natural mineralization material filling layer is 1.8 m, and the average particle size of zeolite and ichthyolite is 1.5 mm.

[0074] The desalinated seawater is conditioned by the seawater desalination water conditioning system of this embodiment. After conditioning, the water body enters the product water tank, and then passes through a feed water pump to enter an ultraviolet sterilizer for sterilization treatment to obtain drinking water. Before conditioning, the pH value of the desalinated seawater is 6.89, the total hardness is 8.66 mg / L, the total alkalinity is 8.30 mg / L, the total dissolved solids is 163.05 mg / L, the LSI is -3.42, the sodium content is 58.23 mg / L, the calcium content is 1.62 mg / L, the magnesium content is 1.12 mg / L, the metasilicic acid content is <1 mg / L, and the strontium content is <0.05 mg / L.

[0075] The pH value of the potable water obtained by tempering treatment in this example is 8.14, the total hardness is 209.15 mg / L, the total alkalinity is 65.52 mg / L, the total dissolved solids is 417.59 mg / L, the LSI is 0.24, the sodium content is 58.20 mg / L, the calcium content is 60.12 mg / L, the magnesium content is 14.33 mg / L, the metasilicic acid content is 6.3 mg / L, the strontium content is 0.36 mg / L, and the turbidity is <1 NTU.

[0076] Example 3

[0077] This example provides a seawater desalination water tempering system, which is different from that in Example 1 in that the inlet water flow rate is 110% of that in Example 1, the mass ratio of zeolite to mugwort stone in the natural mineralization material is 1:5, the calcination temperature of the mugwort stone is 400 °C, and the calcination time is 2 h. The thickness of the quartz sand filling layer is 0.25 m, the average particle size of the quartz sand in the quartz sand filling layer is 5.0 mm, the thickness of the natural mineralization material filling layer is 2.2 m, and the average particle sizes of the zeolite and the mugwort stone are 0.5 mm.

[0078] The seawater desalination water is tempered by the seawater desalination water tempering system in this example. After tempering treatment, the water body enters the product water tank and then enters the ultraviolet sterilizer through a water supply pump for sterilization treatment to obtain potable water. Before tempering treatment, the pH value of the seawater desalination water is 6.74, the total hardness is 11.30 mg / L, the total alkalinity is 10.58 mg / L, the total dissolved solids is 167.09 mg / L, the LSI is -3.28, the sodium content is 58.97 mg / L, the calcium content is 2.45 mg / L, the magnesium content is 1.26 mg / L, the metasilicic acid content is <1 mg / L, and the strontium content is <0.05 mg / L.

[0079] The pH value of the potable water obtained by tempering treatment in this example is 8.07, the total hardness is 247.01 mg / L, the total alkalinity is 80.87 mg / L, the total dissolved solids is 446.16 mg / L, the LSI is 0.29, the sodium content is 58.92 mg / L, the calcium content is 69.20 mg / L, the magnesium content is 15.38 mg / L, the metasilicic acid content is 6.8 mg / L, the strontium content is 0.46 mg / L, and the turbidity is <1 NTU.

[0080] Example 4

[0081] This embodiment provides a seawater desalination water conditioning system, which is different from that of Embodiment 1 in that the inlet water flow rate is 120% of that of Embodiment 1, the mass ratio of zeolite to mugwort stone in the natural mineralization material is 1:4.5, the calcination temperature of the mugwort stone is 450 °C, and the calcination time is 1.5 h. The thickness of the quartz sand filling layer is 0.22 m, the average particle size of the quartz sand in the quartz sand filling layer is 3.0 mm, the thickness of the natural mineralization material filling layer is 1.9 m, and the average particle size of the zeolite and the mugwort stone is 1.2 mm.

[0082] The seawater desalination water is conditioned by the seawater desalination water conditioning system of this embodiment. The conditioned water body enters the product water tank and then enters the ultraviolet sterilizer through the feed water pump for sterilization treatment to obtain drinking water. Before the seawater desalination water is conditioned, the pH value is 6.71, the total hardness is 15.37 mg / L, the total alkalinity is 13.92 mg / L, the dissolved total solids is 203.14 mg / L, the LSI is -3.09, the sodium content is 70.86 mg / L, the calcium content is 3.22 mg / L, the magnesium content is 1.78 mg / L, the metasilicate content is <1 mg / L, and the strontium content is <0.05 mg / L.

[0083] The pH value of the drinking water obtained by conditioning in this embodiment is 7.86, the total hardness is 207.51 mg / L, the total alkalinity is 72.07 mg / L, the dissolved total solids is 444.10 mg / L, the LSI is 0.01, the sodium content is 70.81 mg / L, the calcium content is 59.63 mg / L, the magnesium content is 14.23 mg / L, the metasilicate content is 6.52 mg / L, the strontium content is 0.33 mg / L, and the turbidity is <1 NTU.

[0084] The various indicators of the drinking water obtained in the above Embodiments 1-4 all meet the ranges specified in the "Hygienic Standards for Drinking Water" GB 5749-2022 and the "Water Quality Requirements for Reverse Osmosis Seawater Desalination Products" GB / T 43230-2023.

[0085] In addition, the number of times the seawater desalination water conditioning systems of Embodiments 1-4 need to be backwashed each year is 2 or 3 times. Compared with using food-grade limestone as the mineralization material, the amount of seawater desalination water consumed during backwashing in Embodiments 1-4 is reduced by about 30%.

[0086] Comparative Example 1

[0087] This embodiment provides a seawater desalination water conditioning system, which is different from that of Embodiment 1 in that the mugwort stone is not calcined.

[0088] The seawater desalination water conditioning system of this comparative example is used to condition the seawater desalination water. The conditioned water body enters the product water tank, and then passes through a feed water pump and enters an ultraviolet sterilizer for sterilization treatment to obtain drinking water. Before conditioning treatment, the pH value of the seawater desalination water is 6.51, the total hardness is 9.88 mg / L, the total alkalinity is 10.10 mg / L, the total dissolved solids is 237.92 mg / L, the LSI is -3.61, the sodium content is 87.5 mg / L, the calcium content is 2.11 mg / L, the magnesium content is 1.12 mg / L, the metasilicic acid content is <1 mg / L, and the strontium content is <0.05 mg / L.

[0089] The pH value of the drinking water obtained by conditioning treatment in this comparative example is 6.84, the total hardness is 65.53 mg / L, the total alkalinity is 37.10 mg / L, the total dissolved solids is 311.98 mg / L, the LSI is -1.90, the sodium content is 87.52 mg / L, the calcium content is 14.32 mg / L, the magnesium content is 7.23 mg / L, the metasilicic acid content is 2.24 mg / L, the strontium content is 0.08 mg / L, and the turbidity is <1 NTU.

[0090] From the above water body parameters, it can be seen that the surface of the uncalcined ichthyolite is relatively dense, and the mineral dissolution property is poor. Therefore, the overall mineralization efficiency is reduced, and the total alkalinity does not reach the range specified in the "Hygienic Standards for Drinking Water" GB 5749-2022 and the "Water Quality Requirements for Reverse Osmosis Seawater Desalination Product Water" GB / T 43230-2023. In addition, the mineral content is insufficient, and the supplementary effects of elements such as calcium, magnesium, metasilicic acid, and strontium are significantly weakened. In addition, the uncalcined ichthyolite has a poor effect on adjusting the pH value of the seawater desalination water, which is still on the low side.

[0091] Comparative Example 2

[0092] This embodiment provides a seawater desalination water conditioning system, which is different from that of Embodiment 1 in that the mass ratio of zeolite to ichthyolite in the natural mineralization material is 1:1.

[0093] The seawater desalination water conditioning system of this comparative example is used to condition the seawater desalination water. The conditioned water body enters the product water tank, and then passes through a feed water pump and enters an ultraviolet sterilizer for sterilization treatment to obtain drinking water. Before conditioning treatment, the pH value of the seawater desalination water is 6.67, the total hardness is 7.30 mg / L, the total alkalinity is 8.73 mg / L, the total dissolved solids is 178.47 mg / L, the LSI is -3.70, the sodium content is 65.48 mg / L, the calcium content is 1.32 mg / L, the magnesium content is 0.98 mg / L, the metasilicic acid content is <1 mg / L, and the strontium content is <0.05 mg / L.

[0094] The pH value of the drinking water obtained by tempering treatment in this comparative example is 7.35, the total hardness is 43.91 mg / L, the total alkalinity is 55.89 mg / L, the total dissolved solids is 242.17 mg / L, the LSI is -1.34, the sodium content is 65.49 mg / L, the calcium content is 10.36 mg / L, the magnesium content is 4.38 mg / L, the metasilicate content is 1.21 mg / L, the strontium content is 0.06 mg / L, and the turbidity is <1 NTU.

[0095] From the above water body parameters, it can be seen that the content of ichthyolite in this comparative example is relatively low, and the minerals provided by ichthyolite are reduced, resulting in the water hardness not reaching the range specified in the "Hygienic Standard for Drinking Water" GB 5749-2022 and the "Water Quality Requirements for Reverse Osmosis Seawater Desalination Product Water" GB / T 43230-2023. Moreover, there are relatively few alkaline substances and insufficient mineral content in the water body.

[0096] Comparative Example 3

[0097] This example provides a seawater desalination water tempering system, which is different from Example 1 in that the mass ratio of zeolite to ichthyolite in the natural mineralization material is 1:8.

[0098] The seawater desalination water is tempered by the seawater desalination water tempering system of this comparative example. After tempering treatment, the water body enters the product water tank and then enters the ultraviolet sterilizer through a water supply pump for sterilization treatment to obtain drinking water. Before tempering treatment, the pH value of the seawater desalination water is 6.91, the total hardness is 9.266 mg / L, the total alkalinity is 10.09 mg / L, the total dissolved solids is 188.87 mg / L, the LSI is -3.34, the sodium content is 68.56 mg / L, the calcium content is 1.55 mg / L, the magnesium content is 1.31 mg / L, the metasilicate content is <1 mg / L, and the strontium content is <0.05 mg / L.

[0099] The pH value of the drinking water obtained by tempering treatment in this comparative example is 8.46, the total hardness is 323.47 mg / L, the total alkalinity is 122.76 mg / L, the total dissolved solids is 662.62 mg / L, the LSI is 1.0, the sodium content is 96.37 mg / L, the calcium content is 89.31 mg / L, the magnesium content is 24.39 mg / L, the metasilicate content is 11.54 mg / L, the strontium content is 0.76 mg / L, and the turbidity is <1 NTU.

[0100] From the above water body parameters, it can be seen that the content of mugwort stone in this comparative example is too high. Mugwort stone contains a large amount of minerals and has good dissolution properties. The excessive dissolution of minerals leads to an increase in the total hardness and total alkalinity of the water body, and the imbalance of mineral precipitation affects the taste and health. Moreover, LSI≥1, and the water quality does not meet the ranges specified in the Hygienic Standard for Drinking Water GB 5749-2022 and the Water Quality Requirements for Reverse Osmosis Seawater Desalination Product Water GB / T 43230-2023, showing a serious tendency to scale.

[0101] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A desalination water conditioning system, characterized in that: Including carbon dioxide dosing equipment and conditioning and filtration equipment; The carbon dioxide dosing equipment is used to dissolve carbon dioxide in desalinated water; The conditioning and filtering equipment is used to condition desalinated seawater containing dissolved carbon dioxide, the conditioning and filtering equipment comprising a conditioning filter (6), the conditioning filter (6) comprising, from bottom to top, a quartz sand filling layer and a natural mineralized material filling layer; In the natural mineralized material filling layer, the natural mineralized material includes zeolite and calcined wooden fish stone, and the mass ratio of zeolite to wooden fish stone is 1:3-1:5; The calcination temperature of wooden fish stone is 400-600℃, and the calcination time is 1-2h; The thickness of the quartz sand filling layer is 0.15-0.25m, and the particle size of the quartz sand in the quartz sand filling layer is 2.5-5.0mm; the thickness of the natural mineralized material filling layer is 1.8-2.2m, and the particle size of the zeolite and wooden fish stone is 0.5-1.5mm; Desalinated water is a water solution obtained by treating seawater through reverse osmosis, electrodialysis, distillation or cryo-separation.

2. The desalination water conditioning system according to claim 1, characterized in that: The carbon dioxide dosing equipment comprises a reverse osmosis water production bypass pressurizing device and a carbon dioxide storage device, a carbon dioxide conversion device and a carbon dioxide dosing mixing device (4) connected in sequence; Both ends of the reverse osmosis water production bypass booster device are respectively connected to the seawater desalination water production bypass pipeline and the carbon dioxide dosing and mixing device (4).

3. The desalination water conditioning system according to claim 2, characterized in that: The reverse osmosis water production bypass boosting device comprises a first boosting pump (3), the carbon dioxide storage device comprises a carbon dioxide storage tank (1), and the carbon dioxide conversion device comprises an evaporator (2) and a pressure reducing and stabilizing component; The other end of the carbon dioxide dosing and mixing device (4) is connected to a main water pipeline of desalinated water, and the main water pipeline of desalinated water is also connected to the conditioning filter (6).

4. The desalination water conditioning system according to claim 1 or 3, characterized in that: The conditioning filter (6) further comprises a water-gas distribution layer arranged below the quartz sand filling layer; The water vapor distribution layer includes a filter plate and a plurality of water distribution structures arranged on the filter plate.

5. The desalination water conditioning system according to claim 1 or 3, characterized in that: The conditioning and filtering equipment also includes a natural mineralized material dosing device located above the natural mineralized material filling layer; The natural mineralized material dosing device comprises a storage bin and a feeding pipe connected to the storage bin. The natural mineralized material is stored in the storage bin. An automatic feeding port is also provided at the upper end of the storage bin.

6. The desalination water conditioning system according to claim 1, characterized in that: The desalinated water conditioning system further comprises an air-water combined backwashing device connected to the conditioning filter (6); The air-water combined backwashing equipment comprises a backwashing fan (7) and a backwashing water booster pump (5).

7. A method for conditioning seawater desalination water using the seawater desalination water conditioning system according to any one of claims 1 to 6, characterized in that: The steps include: S1: adding carbon dioxide to desalinated water through a carbon dioxide dosing device to obtain desalinated water containing dissolved carbon dioxide; S2: Desalinated seawater containing dissolved carbon dioxide passes through the quartz sand filling layer and the natural mineral material filling layer of the conditioning filter in turn, and is filtered and tempered to obtain drinking water that meets drinking standards.

8. The method for conditioning desalinated water according to claim 7, characterized in that: In step S1, carbon dioxide is added to the desalinated water from the desalinated water bypass pipeline by a carbon dioxide adding device to obtain desalinated water containing dissolved carbon dioxide; In step S2, desalinated water containing dissolved carbon dioxide enters the desalinated water main pipeline, and then passes through the quartz sand filling layer and the natural mineral material filling layer of the conditioning filter in sequence, and is filtered and tempered to obtain drinking water that meets drinking standards.

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