A method for recycling and reducing discharge of sewage water from circulating cooling water of a water-cooled machine room

Abstract

The application discloses a kind of water-cooled machine room circulating cooling water's sewage reuse processing and emission reduction method, belong to cooling water processing technical field, this method includes that raw water is sequentially filtered by hollow fiber ultrafiltration membrane system, security filter and reverse osmosis treatment obtains after processing reuse water;Wherein, in the reverse osmosis treatment process, first add scale inhibitor, then be treated by reverse osmosis membrane module;In the preparation of scale inhibitor, first cinnamonoyl chloride is dissolved in tetrahydrofuran, under the action of triethylamine, and 5-amino nonane-5-carboxylic acid is reacted, then free radical polymerization is carried out under the action of azobisisobutyronitrile to obtain scale inhibitor.The application uses the above-prepared scale inhibitor to treat the sewage of water-cooled machine room circulating cooling water, while ensuring good scale inhibition effect, significantly improves the recovery rate of reuse water.

Description

Technical Field

[0001] This invention relates to the field of cooling water treatment technology, specifically to a method for the reuse and reduction of wastewater from circulating cooling water in a water-cooled computer room. Background Technology

[0002] Circulating cooling water systems generally employ an open design. While this design offers advantages such as high heat dissipation efficiency and low operating costs, over long-term operation, the continuous evaporation and concentration of the circulating cooling water leads to a sustained increase in the concentration of dissolved salts, resulting in severe scaling and corrosion problems. These issues not only significantly reduce the heat transfer efficiency of heat exchange equipment and increase energy consumption, but can also damage equipment due to localized corrosion or scaling blockage, shortening its service life and causing substantial economic losses.

[0003] While traditional treatment methods can alleviate scaling problems to some extent, they often have drawbacks such as environmental pollutant emissions, chemical residues, and accelerated equipment corrosion, potentially even shortening equipment lifespan. Furthermore, traditional methods typically fail to address water conservation needs; large-scale wastewater discharge not only wastes water resources but may also lead to stricter environmental regulations due to high-salinity wastewater discharge. Therefore, developing novel wastewater reuse and emission reduction methods for water-cooled computer room circulating cooling water has significant practical importance and promising application prospects. Summary of the Invention

[0004] The purpose of this invention is to provide a method for the reuse and emission reduction of wastewater from circulating cooling water in water-cooled computer rooms. By optimizing the treatment process, the scale inhibition effect in wastewater treatment is significantly improved, effectively controlling the corrosion and scaling risks of wastewater treatment, while increasing the recovery rate of recycled water, thereby achieving energy saving and emission reduction effects. The technical solution adopted by the present invention to achieve the above objectives is as follows: A method for treating and reducing wastewater discharge from circulating cooling water in a water-cooled computer room includes sequentially passing raw water through a hollow fiber ultrafiltration membrane system, a security filter, and reverse osmosis to obtain treated reclaimed water; the raw water flow rate is 1-5 m³ / h. 3 / h.

[0005] This invention addresses the need for efficient reuse and emission reduction of wastewater from circulating cooling water systems in medium and large-sized data center water-cooled server rooms. It proposes a method for treating and reducing the wastewater from these systems. The method employs a hollow fiber ultrafiltration membrane system, combined with a security filter and reverse osmosis, to obtain treated reclaimed water. This wastewater reuse and emission reduction method effectively removes most salt pollutants, prevents corrosion and scaling during wastewater treatment, extends the lifespan of wastewater treatment equipment, significantly reduces wastewater treatment costs, and improves wastewater recycling efficiency, achieving significant environmental benefits in both water conservation and pollutant reduction.

[0006] Preferably, during the reverse osmosis process, a scaling inhibitor is added first, followed by treatment with a reverse osmosis membrane module.

[0007] More preferably, the amount of scaling inhibitor used is 0.02-0.04 wt% of the raw water volume.

[0008] More preferably, in the preparation of the scale inhibitor, cinnamyl chloride is first dissolved in tetrahydrofuran, reacted with 5-aminononane-5-carboxylic acid under the action of triethylamine, and then subjected to free radical polymerization under the action of a modifier to obtain the scale inhibitor.

[0009] More preferably, the mass ratio of cinnamyl chloride to triethylamine is 1:1-5.

[0010] More preferably, the ratio of triethylamine to tetrahydrofuran is 1g:5-20mL.

[0011] More preferably, the mass ratio of triethylamine to 5-aminononane-5-carboxylic acid is 1:1-3.

[0012] More preferably, the modifier includes azobisisobutyronitrile, triethylamine and azobisisobutyronitrile in a mass ratio of 1:0.01-0.1.

[0013] More preferably, the free radical polymerization reaction temperature is 70-90℃.

[0014] More preferably, the free radical polymerization reaction time is 8-24 hours.

[0015] More preferably, the preparation of the scaling inhibitor specifically involves, Cinnamyl chloride was dissolved in tetrahydrofuran under nitrogen atmosphere, and triethylamine was added and stirred until homogeneous. 5-Aminononane-5-carboxylic acid was slowly added under ice bath conditions for 0.5-2 hours, followed by reaction at room temperature for 12-24 hours. After the reaction was complete, a modifier was added, and the mixture was reacted at 70-90℃ for 8-24 hours. The mixture was then filtered, the solvent removed by rotary evaporation, washed 2-5 times with deionized water, and vacuum dried to obtain the scale inhibitor. The scale inhibitor prepared by this invention contains abundant carboxyl groups, which may interfere with and inhibit the growth process of microcrystals through the chelation of carboxyl groups with scale-forming ions, thereby effectively preventing scale formation and significantly improving scale inhibition efficiency. In dual-membrane water systems, it can also alleviate the problem of membrane flux decline caused by ion scaling, thereby improving the recovery rate of treated reclaimed water.

[0016] More preferably, the mass ratio of cinnamyl chloride to triethylamine is 1:1-5.

[0017] More preferably, the ratio of triethylamine to tetrahydrofuran is 1g:5-20mL.

[0018] More preferably, the mass ratio of triethylamine to 5-aminononane-5-carboxylic acid is 1:1-3.

[0019] More preferably, the modifier includes azobisisobutyronitrile, triethylamine and azobisisobutyronitrile in a mass ratio of 1:0.01-0.1.

[0020] More preferably, the modifier includes azobisisobutyronitrile (AIBN) and methyl 3-hydroxyhexanoate, with a mass ratio of triethylamine to AIBN of 1:0.01-0.1, and a mass ratio of triethylamine to methyl 3-hydroxyhexanoate of 1:1-5. This invention further introduces hydroxyl groups into the molecular structure of the scale inhibitor, constructing a stable double-electron layer structure on the surface of sparingly soluble or insoluble inorganic salt crystals, reducing collisions between microcrystals, thereby preventing crystal precipitation and crystallization, further improving scale inhibition efficiency and the recovery rate of treated reclaimed water.

[0021] Preferably, a method for the reuse and treatment of wastewater from the circulating cooling water in a water-cooled computer room and for reducing emissions specifically includes: Using the wastewater from the circulating cooling water in the water-cooled machine room as raw water, the raw water is first pumped to the hollow fiber ultrafiltration membrane system for ultrafiltration by a booster pump. The ultrafiltration permeate enters the intermediate water tank, and then enters the security filter for filtration by a booster pump. The filtered permeate is then treated by reverse osmosis, and the reverse osmosis permeate enters the permeate tank, ultimately resulting in treated reclaimed water.

[0022] More preferably, the raw water flow rate is 1-5m³ / h. 3 / h.

[0023] More preferably, in the reverse osmosis process, the membrane is pumped into the reverse osmosis membrane module for treatment.

[0024] More preferably, in the reverse osmosis process, a scaling inhibitor is added first, and then the solution is pumped into the reverse osmosis membrane module for treatment.

[0025] More preferably, the amount of scaling inhibitor used is equivalent to 0.02-0.04 wt% of the raw water volume.

[0026] This invention, by applying a scaling inhibitor to the wastewater reuse and emission reduction method for circulating cooling water in water-cooled machine rooms, offers the following advantages: The invention employs an ultrafiltration-reverse osmosis treatment process, eliminating the need for complex additional equipment and altering the components or materials of existing treatment equipment, resulting in high economic efficiency and strong adaptability. The water treated after wastewater recovery removes most of the pollutants such as salts and can be reused as makeup water, thereby reducing wastewater discharge, lowering energy consumption in the circulating water system, reducing wastewater treatment costs, conserving water resources, and achieving energy conservation and emission reduction. This has a positive social impact on promoting industrial development. The scaling inhibitor prepared by this invention exhibits good scale inhibition performance, with a calcium ion scale inhibition rate of 70.1-95.7%, reducing the risk of reverse osmosis membrane fouling due to ion scaling and lowering metal corrosion rates. Applying the scaling inhibitor to the wastewater reuse and emission reduction method for circulating cooling water in water-cooled machine rooms helps improve membrane treatment efficiency, thereby increasing the permeate recovery rate to 58.4-91.2%, resulting in significant economic benefits. Therefore, this invention provides a method for the reuse and emission reduction of wastewater from circulating cooling water in water-cooled machine rooms, which has good scale inhibition effect and high water recovery rate. Attached Figure Description

[0027] Figure 1 The infrared spectrum of the scaling inhibitor. Detailed Implementation

[0028] The present invention will now be described in further detail with reference to specific embodiments. The given embodiments are merely illustrative of the invention and not intended to limit its scope. The embodiments provided below can serve as a guide for further improvements by those skilled in the art and do not constitute a limitation on the invention in any way.

[0029] Unless otherwise specified, the experimental methods used in the following examples are conventional methods. Unless otherwise specified, the materials and reagents used in the following examples are commercially available.

[0030] Example 1: A method for the reuse and treatment of wastewater from a water-cooled computer room's circulating cooling water, and for reducing emissions, includes: Using wastewater from the circulating cooling water system of the water-cooled computer room as raw water, the raw water is first pumped to a hollow fiber ultrafiltration membrane system for ultrafiltration via a booster pump. The ultrafiltration permeate enters an intermediate water tank, then passes through a security filter via another booster pump. The filtered permeate is then pumped through a high-pressure pump to a reverse osmosis membrane module for further treatment. The resulting reverse osmosis permeate enters a permeate tank, ultimately becoming treated reclaimed water. The hollow fiber ultrafiltration membrane system is manufactured by Tianjin Membrane Technology Co., Ltd., and the reverse osmosis membrane module is manufactured by Guizhou Shidai Huitong Membrane Technology Co., Ltd. The raw water flow rate is 3 m³ / h. 3 / h.

[0031] Example 2: The preparation of scaling inhibitors includes, Cinnamyl chloride was dissolved in tetrahydrofuran under nitrogen atmosphere, and triethylamine was added and stirred until homogeneous. 5-Aminononane-5-carboxylic acid was slowly added under ice bath conditions and reacted for 1 hour. The reaction was then carried out at room temperature for 24 hours. After the reaction was complete, azobisisobutyronitrile was added, and the mixture was reacted at 70°C for 12 hours. The mixture was filtered, the solvent was removed by rotary evaporation, and the solution was washed three times with deionized water and dried under vacuum to obtain the scaling inhibitor. The mass ratio of cinnamyl chloride to triethylamine was 1:2; the mass ratio of triethylamine to tetrahydrofuran was 1 g:10 mL; the mass ratio of triethylamine to 5-aminononane-5-carboxylic acid was 1:1.5; and the mass ratio of triethylamine to azobisisobutyronitrile was 1:0.05.

[0032] A method for the reuse and treatment of wastewater from a water-cooled computer room's circulating cooling water, and for reducing emissions, includes: Using wastewater from the circulating cooling water system of the water-cooled computer room as raw water, the raw water is first pumped to a hollow fiber ultrafiltration membrane system for ultrafiltration via a booster pump. The resulting ultrafiltration permeate enters an intermediate water tank, then passes through a security filter via another booster pump. A scaling inhibitor is added to the filtered permeate, which is then pumped through a high-pressure pump to a reverse osmosis membrane module for further treatment. The resulting reverse osmosis permeate enters a permeate tank and is ultimately treated for reuse. The hollow fiber ultrafiltration membrane system is manufactured by Tianjin Membrane Technology Co., Ltd., and the reverse osmosis membrane module is manufactured by Guizhou Shidai Huitong Membrane Technology Co., Ltd. The raw water flow rate is 3 m³ / h. 3 / h. The dosage of scale inhibitor is equivalent to 0.04wt% of the raw water volume.

[0033] Example 3: The preparation of scaling inhibitors includes, Cinnamyl chloride was dissolved in tetrahydrofuran under nitrogen atmosphere, and triethylamine was added and stirred until homogeneous. 5-Aminononane-5-carboxylic acid was slowly added under ice bath conditions and reacted for 1 hour. The reaction was then carried out at room temperature for 24 hours. After the reaction was complete, azobisisobutyronitrile was added, and the mixture was reacted at 70°C for 12 hours. The mixture was filtered, the solvent was removed by rotary evaporation, and the solution was washed three times with deionized water and dried under vacuum to obtain the scaling inhibitor. The mass ratio of cinnamyl chloride to triethylamine was 1:2; the mass ratio of triethylamine to tetrahydrofuran was 1 g:10 mL; the mass ratio of triethylamine to 5-aminononane-5-carboxylic acid was 1:1.5; and the mass ratio of triethylamine to azobisisobutyronitrile was 1:0.05.

[0034] A method for the reuse and treatment of wastewater from a water-cooled computer room's circulating cooling water, and for reducing emissions, includes: Using wastewater from the circulating cooling water system of the water-cooled computer room as raw water, the raw water is first pumped to a hollow fiber ultrafiltration membrane system for ultrafiltration via a booster pump. The resulting ultrafiltration permeate enters an intermediate water tank, then passes through a security filter via another booster pump. A scaling inhibitor is added to the filtered permeate, which is then pumped through a high-pressure pump to a reverse osmosis membrane module for further treatment. The resulting reverse osmosis permeate enters a permeate tank and is ultimately treated for reuse. The hollow fiber ultrafiltration membrane system is manufactured by Tianjin Membrane Technology Co., Ltd., and the reverse osmosis membrane module is manufactured by Guizhou Shidai Huitong Membrane Technology Co., Ltd. The raw water flow rate is 3 m³ / h. 3 / h. The dosage of scale inhibitor is equivalent to 0.02wt% of the raw water volume.

[0035] Example 4: The preparation of scaling inhibitors includes, Cinnamyl chloride was dissolved in tetrahydrofuran under nitrogen atmosphere, and triethylamine was added and stirred until homogeneous. 5-Aminononane-5-carboxylic acid was slowly added under ice bath conditions and reacted for 1 hour. The reaction was then carried out at room temperature for 24 hours. After the reaction was complete, azobisisobutyronitrile and methyl 3-hydroxyhexanoate were added, and the mixture was reacted at 70°C for 12 hours. The mixture was filtered, the solvent was removed by rotary evaporation, and the solution was washed three times with deionized water and dried under vacuum to obtain the scaling inhibitor. The mass ratio of cinnamyl chloride to triethylamine was 1:2; the mass ratio of triethylamine to tetrahydrofuran was 1 g:10 mL; the mass ratio of triethylamine to 5-aminononane-5-carboxylic acid was 1:1.5; the mass ratio of triethylamine to azobisisobutyronitrile was 1:0.05; and the mass ratio of triethylamine to methyl 3-hydroxyhexanoate was 1:2.

[0036] A method for the reuse and treatment of wastewater from a water-cooled computer room's circulating cooling water, and for reducing emissions, includes: Using wastewater from the circulating cooling water system of the water-cooled computer room as raw water, the raw water is first pumped to a hollow fiber ultrafiltration membrane system for ultrafiltration via a booster pump. The resulting ultrafiltration permeate enters an intermediate water tank, then passes through a security filter via another booster pump. A scaling inhibitor is added to the filtered permeate, which is then pumped through a high-pressure pump to a reverse osmosis membrane module for further treatment. The resulting reverse osmosis permeate enters a permeate tank and is ultimately treated for reuse. The hollow fiber ultrafiltration membrane system is manufactured by Tianjin Membrane Technology Co., Ltd., and the reverse osmosis membrane module is manufactured by Guizhou Shidai Huitong Membrane Technology Co., Ltd. The raw water flow rate is 3 m³ / h. 3 / h. The dosage of scale inhibitor is equivalent to 0.04wt% of the raw water volume.

[0037] Example 5: The preparation of scaling inhibitors includes, Cinnamyl chloride was dissolved in tetrahydrofuran under nitrogen atmosphere, and triethylamine was added and stirred until homogeneous. 5-Aminononane-5-carboxylic acid was slowly added under ice bath conditions and reacted for 1 hour. The reaction was then carried out at room temperature for 24 hours. After the reaction was complete, azobisisobutyronitrile and methyl 3-hydroxyhexanoate were added, and the mixture was reacted at 70°C for 12 hours. The mixture was filtered, the solvent was removed by rotary evaporation, and the solution was washed three times with deionized water and dried under vacuum to obtain the scaling inhibitor. The mass ratio of cinnamyl chloride to triethylamine was 1:2; the mass ratio of triethylamine to tetrahydrofuran was 1 g:10 mL; the mass ratio of triethylamine to 5-aminononane-5-carboxylic acid was 1:1.5; the mass ratio of triethylamine to azobisisobutyronitrile was 1:0.05; and the mass ratio of triethylamine to methyl 3-hydroxyhexanoate was 1:2.

[0038] A method for the reuse and treatment of wastewater from a water-cooled computer room's circulating cooling water, and for reducing emissions, includes: Using wastewater from the circulating cooling water system of the water-cooled computer room as raw water, the raw water is first pumped to a hollow fiber ultrafiltration membrane system for ultrafiltration via a booster pump. The resulting ultrafiltration permeate enters an intermediate water tank, then passes through a security filter via another booster pump. A scaling inhibitor is added to the filtered permeate, which is then pumped through a high-pressure pump to a reverse osmosis membrane module for further treatment. The resulting reverse osmosis permeate enters a permeate tank and is ultimately treated for reuse. The hollow fiber ultrafiltration membrane system is manufactured by Tianjin Membrane Technology Co., Ltd., and the reverse osmosis membrane module is manufactured by Guizhou Shidai Huitong Membrane Technology Co., Ltd. The raw water flow rate is 3 m³ / h. 3 / h. The dosage of scale inhibitor is equivalent to 0.02wt% of the raw water volume.

[0039] Comparative Example 1: The preparation of scaling inhibitors includes, Under nitrogen atmosphere, 5-aminononane-5-carboxylic acid was dissolved in tetrahydrofuran, and triethylamine was added and stirred until homogeneous. The mixture was then reacted at room temperature for 24 h. After the reaction was complete, azobisisobutyronitrile was added, and the mixture was reacted at 70 °C for 12 h. The mixture was then filtered, the solvent was removed by rotary evaporation, and the solution was washed three times with deionized water and dried under vacuum to obtain the scaling inhibitor. The molar ratio of triethylamine to tetrahydrofuran was 1 g:10 mL; the mass ratio of triethylamine to 5-aminononane-5-carboxylic acid was 1:1.5; and the mass ratio of triethylamine to azobisisobutyronitrile was 1:0.05.

[0040] A method for the reuse and treatment of wastewater from a water-cooled computer room's circulating cooling water, and for reducing emissions, includes: Using wastewater from the circulating cooling water system of the water-cooled computer room as raw water, the raw water is first pumped to a hollow fiber ultrafiltration membrane system for ultrafiltration via a booster pump. The resulting ultrafiltration permeate enters an intermediate water tank, then passes through a security filter via another booster pump. A scaling inhibitor is added to the filtered permeate, which is then pumped through a high-pressure pump to a reverse osmosis membrane module for further treatment. The resulting reverse osmosis permeate enters a permeate tank and is ultimately treated for reuse. The hollow fiber ultrafiltration membrane system is manufactured by Tianjin Membrane Technology Co., Ltd., and the reverse osmosis membrane module is manufactured by Guizhou Shidai Huitong Membrane Technology Co., Ltd. The raw water flow rate is 3 m³ / h. 3 / h. The dosage of scale inhibitor is equivalent to 0.04wt% of the raw water volume.

[0041] Comparative Example 2: The preparation of scaling inhibitors includes, Under nitrogen atmosphere, triethylamine was added to tetrahydrofuran and stirred until homogeneous. The mixture was reacted in an ice bath for 1 hour, then at room temperature for 24 hours. After the reaction was complete, azobisisobutyronitrile and methyl 3-hydroxyhexanoate were added, and the mixture was reacted at 70°C for 12 hours. The mixture was then filtered, the solvent was removed by rotary evaporation, and the mixture was washed three times with deionized water and dried under vacuum to obtain the scaling inhibitor. The ratio of triethylamine to tetrahydrofuran was 1 g:10 mL; the mass ratio of triethylamine to azobisisobutyronitrile was 1:0.05; and the mass ratio of triethylamine to methyl 3-hydroxyhexanoate was 1:2.

[0042] A method for the reuse and treatment of wastewater from a water-cooled computer room's circulating cooling water, and for reducing emissions, includes: Using wastewater from the circulating cooling water system of the water-cooled computer room as raw water, the raw water is first pumped to a hollow fiber ultrafiltration membrane system for ultrafiltration via a booster pump. The resulting ultrafiltration permeate enters an intermediate water tank, then passes through a security filter via another booster pump. A scaling inhibitor is added to the filtered permeate, which is then pumped through a high-pressure pump to a reverse osmosis membrane module for further treatment. The resulting reverse osmosis permeate enters a permeate tank and is ultimately treated for reuse. The hollow fiber ultrafiltration membrane system is manufactured by Tianjin Membrane Technology Co., Ltd., and the reverse osmosis membrane module is manufactured by Guizhou Shidai Huitong Membrane Technology Co., Ltd. The raw water flow rate is 3 m³ / h. 3 / h. The dosage of scale inhibitor is equivalent to 0.04wt% of the raw water volume.

[0043] Experimental example: 1. Material Characterization The scaling inhibitor prepared in Example 2 was purified and vacuum dried. Samples were prepared using the potassium bromide tablet coating method and analyzed using Fourier transform infrared spectroscopy at 400-4000 cm⁻¹. -1 Infrared scanning was performed within the wavelength range, with a test resolution of 4.0 cm. -1 The average value was taken from 32 trials.

[0044] Figure 1 Infrared spectrum of the scaling inhibitor. 3400 cm⁻¹ -1 An absorption peak for OH appears nearby, at 2900 cm⁻¹. -1 An absorption peak for CH appears nearby, at 1690 cm⁻¹. -1 An absorption peak appears near C=O, at 1630 cm⁻¹. -1 An absorption peak for C=C appears nearby.

[0045] 2. Calcium ion scale inhibition rate 100 mL of filtered permeate and treated reclaimed water samples were taken from the wastewater reuse and emission reduction methods for water-cooled machine room circulating cooling water in Examples 1-5 and Comparative Examples 1-2, respectively. The calcium ion content was determined according to the national standard GB 7476-87 "Determination of Calcium in Water - EDTA Titration Method". The calcium ion content of the filtered permeate sample was recorded as C1, and the calcium ion content of the treated reclaimed water sample was recorded as C2. The calcium ion scale inhibition rate was calculated using the formula: Scale inhibition rate (%) = (C1 - C2) / C1 × 100%.

[0046] Table 1. Scale inhibition rate (%)

[0047] As shown in Table 1, the scale inhibition rates of Examples 2-3 of the present invention are higher than those of Example 1. This is because Examples 2-3 first use cinnamyl chloride and 5-aminononane-5-carboxylic acid to react, and then perform a polymerization reaction under the action of azobisisobutyronitrile to obtain a scale inhibitor. The scale inhibitor is then applied to the wastewater reuse treatment and emission reduction method of the circulating cooling water in the water-cooled computer room. In contrast, Example 1 did not use a scale inhibitor in its wastewater reuse treatment and emission reduction method for the circulating cooling water in the water-cooled computer room. The scale inhibition rate of Example 2 is higher than that of Example 3 because the amount of scale inhibitor used is different. The scale inhibition rate of Examples 2-3 of the present invention is higher than that of Comparative Example 1 because, in the preparation of the scale inhibitor, Comparative Example 1 did not use cinnamyl chloride and 5-aminononane-5-carboxylic acid to react; instead, it only performed a polymerization reaction of 5-aminononane-5-carboxylic acid under the action of azobisisobutyronitrile to obtain the scale inhibitor. This indicates that applying the scale inhibitor prepared by the present invention to the wastewater reuse treatment and emission reduction method of the circulating cooling water in the water-cooled computer room helps to improve the scale inhibition effect.

[0048] The scale inhibition rates of Examples 4-5 of this invention are higher than those of Example 2 because, in the preparation of the scale inhibitor, Examples 4-5 further added methyl 3-hydroxyhexane-5-enoate for polymerization to obtain the scale inhibitor. The scale inhibition rates of Examples 4-5 of this invention are higher than those of Comparative Example 2 because, in the preparation of the scale inhibitor, Comparative Example 2 only used methyl 3-hydroxyhexane-5-enoate for polymerization under the action of azobisisobutyronitrile to obtain the scale inhibitor. The scale inhibition rate of Example 4 is higher than that of Example 5 because the amount of scale inhibitor used is different in the wastewater reuse treatment and emission reduction method for circulating cooling water in water-cooled machine rooms. This indicates that this invention first uses cinnamyl chloride and 5-aminononane-5-carboxylic acid to react, then polymerizes it with methyl 3-hydroxyhexane-5-enoate under the action of azobisisobutyronitrile to obtain the scale inhibitor. Applying the prepared scale inhibitor to the wastewater reuse treatment and emission reduction method for circulating cooling water in water-cooled machine rooms helps to further improve the scale inhibition effect.

[0049] 3. Recovery rate of treated reclaimed water The raw water influent and the treated recycled water effluent were measured in Examples 1-5 and Comparative Examples 1-2 respectively at the 5th hour of raw water treatment. The raw water influent was recorded as M1, and the treated recycled water effluent was recorded as M2. The recovery rate of the treated recycled water (%) = M2 / M1 × 100%.

[0050] Table 2 Recovery rate (%)

[0051] As shown in Table 2, the recovery rates of Examples 2-3 of this invention are higher than those of Example 1. This is because Examples 2-3 first use cinnamyl chloride and 5-aminononane-5-carboxylic acid to react, and then perform a polymerization reaction under the action of azobisisobutyronitrile to obtain a scaling inhibitor. The scaling inhibitor is then applied to the wastewater reuse treatment and emission reduction method for circulating cooling water in water-cooled computer rooms. In contrast, Example 1 did not use a scaling inhibitor in its wastewater reuse treatment and emission reduction method for circulating cooling water in water-cooled computer rooms. The recovery rate of Example 2 is higher than that of Example 3 due to the different amounts of scaling inhibitor used. The recovery rates of Examples 2-3 of this invention are higher than those of Comparative Example 1 because, in the preparation of the scaling inhibitor, Comparative Example 1 did not use cinnamyl chloride and 5-aminononane-5-carboxylic acid to react; instead, it only performed a polymerization reaction of 5-aminononane-5-carboxylic acid under the action of azobisisobutyronitrile to obtain the scaling inhibitor. This indicates that applying the scaling inhibitor prepared by this invention to the wastewater reuse treatment and emission reduction method for circulating cooling water in water-cooled computer rooms helps to improve the recovery rate of the treated recycled water.

[0052] The recovery rates of Examples 4-5 of this invention are higher than those of Example 2 because, in the preparation of the scale inhibitor, Examples 4-5 further added methyl 3-hydroxyhexanoate for polymerization to obtain the scale inhibitor. The recovery rates of Examples 4-5 of this invention are higher than those of Comparative Example 2 because, in the preparation of the scale inhibitor, Comparative Example 2 only used methyl 3-hydroxyhexanoate for polymerization under the action of azobisisobutyronitrile to obtain the scale inhibitor. The scale inhibition rate of Example 4 is higher than that of Example 5 because the amount of scale inhibitor used is different in the wastewater reuse treatment and emission reduction method for circulating cooling water in water-cooled machine rooms. This indicates that this invention first uses cinnamyl chloride and 5-aminononane-5-carboxylic acid to react, then polymerizes it with methyl 3-hydroxyhexanoate under the action of azobisisobutyronitrile to obtain the scale inhibitor. The prepared scale inhibitor is then applied to the wastewater reuse treatment and emission reduction method for circulating cooling water in water-cooled machine rooms, which helps to further improve the recovery rate of the treated recycled water.

[0053] The conventional operations in the operation steps of this invention are well known to those skilled in the art and will not be described in detail here.

[0054] The embodiments described above provide a detailed explanation of the technical solutions of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, additions, or similar substitutions made within the scope of the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for the reuse and treatment of wastewater from circulating cooling water in a water-cooled machine room, comprising: Raw water is sequentially passed through a hollow fiber ultrafiltration membrane system, a security filter, and a reverse osmosis treatment to obtain treated reclaimed water. The raw water flow rate is 1-5m³ / h. 3 / h; In the reverse osmosis process, a scaling inhibitor is first added, and then the solution is processed through a reverse osmosis membrane module. In the preparation of the scale inhibitor, cinnamoyl chloride is first dissolved in tetrahydrofuran, and then reacted with 5-aminononane-5-carboxylic acid under the action of triethylamine. Azobisisobutyronitrile and methyl 3-hydroxyhex-5-enoate are added to carry out a free radical polymerization reaction to obtain the scale inhibitor. The mass ratio of cinnamyl chloride to triethylamine is 1:1-5; The ratio of triethylamine to tetrahydrofuran is 1g:5-20mL; The mass ratio of triethylamine to 5-aminononane-5-carboxylic acid is 1:1-3; The mass ratio of triethylamine to azobisisobutyronitrile is 1:0.01-0.

1.

2. The method according to claim 1, characterized in that, The dosage of the scaling inhibitor is 0.02-0.04 wt% of the raw water volume.

3. The method according to claim 1, characterized in that, The free radical polymerization reaction temperature is 70-90℃.

4. The method according to claim 1, characterized in that, The free radical polymerization reaction time is 8-24 hours.

5. The method according to claim 1, characterized in that, The preparation of the scaling inhibitor is specifically as follows: under nitrogen conditions, cinnamoyl chloride is dissolved in tetrahydrofuran, triethylamine is added and stirred evenly, 5-aminononane-5-carboxylic acid is slowly added under ice bath conditions and reacted for 0.5-2 hours, and then reacted at room temperature for 12-24 hours. After the reaction is completed, azobisisobutyronitrile and methyl 3-hydroxyhexyl-5-enoate are added and reacted at 70-90℃ for 8-24 hours. Subsequently, the mixture is filtered, the solvent is removed by rotary evaporation, washed 2-5 times with deionized water, and dried under vacuum to obtain the scaling inhibitor.

6. The method according to any one of claims 1-5, characterized in that, The mass ratio of triethylamine to methyl 3-hydroxyhexyl-5-enoate is 1:1-5.

7. The method according to claim 1, characterized in that, Specifically, the wastewater from the circulating cooling water in the water-cooled machine room is used as the raw water. The raw water is first pumped to the hollow fiber ultrafiltration membrane system for ultrafiltration by a booster pump. The ultrafiltration product water enters the intermediate water tank, and then enters the security filter for filtration by a booster pump. The filtered product water is then treated by reverse osmosis, and the reverse osmosis product water enters the product water tank, and finally becomes treated recycled water.

8. The method according to claim 1, characterized in that, In reverse osmosis, the material is pumped into the reverse osmosis membrane module for processing.

9. The method according to claim 1, characterized in that, In reverse osmosis, scaling inhibitors are added first, and then the solution is pumped into the reverse osmosis membrane module for treatment.

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