Discharge water reuse treatment and emission reduction method for circulating cooling water of water-cooling machine room

Abstract

The invention discloses a sewage reuse treatment and emission reduction method for circulating cooling water of a water cooling machine room, and belongs to the technical field of cooling water treatment.The method comprises the steps that raw water is subjected to ultrafiltration through a hollow fiber ultrafiltration membrane system, filtration through a security filter and reverse osmosis treatment in sequence, and treated reuse water is obtained; wherein in the reverse osmosis treatment process, a scaling inhibitor is added firstly, and then treatment is performed through a reverse osmosis membrane assembly; the preparation method of the scaling inhibitor comprises the following steps: dissolving cinnamyl chloride in tetrahydrofuran, reacting with 5-aminononane-5-carboxylic acid under the action of triethylamine, and performing free radical polymerization reaction under the action of azodiisobutyronitrile to obtain the scaling inhibitor. The prepared scaling inhibitor is used for treating sewage of circulating cooling water of the water-cooling machine room, and the recovery rate of reuse water is remarkably increased while the good scaling inhibition effect is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of cooling water treatment, and in particular to a method for recycling and reducing wastewater of circulating cooling water in a water-cooled machine room. Background Art

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

[0003] While traditional treatment methods can alleviate scaling to some extent, they often pose drawbacks such as environmental pollutant emissions, residual chemicals, and increased equipment corrosion, potentially shortening equipment lifespan. Furthermore, traditional methods often fail to address water conservation needs. Excessive wastewater discharge not only wastes water resources but also risks facing stricter environmental regulations due to the high salinity of wastewater. Therefore, developing novel methods for wastewater reuse and emission reduction in circulating cooling water for water-cooled machine rooms holds significant practical significance and promise. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for recycling and reducing the wastewater of circulating cooling water in a water-cooled machine room. By optimizing the treatment process, the scale inhibition effect in wastewater treatment is significantly improved, the corrosion and scaling risks of wastewater treatment are effectively controlled, and the recovery rate of recycled water is increased, thereby achieving the effect of energy saving and emission reduction. The technical solution adopted by the present invention to achieve the above-mentioned purpose is: A method for recycling and reducing the wastewater of circulating cooling water in a water-cooled machine room, comprising: treating the raw water by ultrafiltration through a hollow fiber ultrafiltration membrane system, filtering through a security filter, and performing reverse osmosis treatment to obtain treated water; the raw water flow rate is 1-5m 3 / h.

[0005] This invention addresses the need for efficient reuse and emission reduction of wastewater from circulating cooling water in water-cooled machine rooms in medium- to large-scale data centers. This method utilizes a hollow fiber ultrafiltration membrane system for ultrafiltration, combined with a safety filter and reverse osmosis treatment, to produce treated reusable water. This wastewater reuse and emission reduction method effectively removes most salt contaminants, effectively prevents corrosion and scaling during wastewater treatment, extends the life of wastewater treatment equipment, significantly reduces wastewater treatment costs, and improves wastewater recycling efficiency, achieving the dual environmental benefits of significant water conservation and pollutant emission reduction.

[0006] Preferably, during the reverse osmosis treatment process, a scaling inhibitor is added first, and then the reverse osmosis membrane assembly is used for treatment.

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

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

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

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

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

[0012] More preferably, the modifier comprises azobisisobutyronitrile, and the mass ratio of triethylamine to azobisisobutyronitrile is 1:0.01-0.1.

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

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

[0015] More preferably, the preparation of the scale inhibitor is specifically, 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 to react for 0.5-2h, and the mixture is placed at room temperature to react for 12-24h. After the reaction is completed, a modifier is added, and the mixture is reacted at 70-90°C for 8-24h, filtered, and the solvent is removed by rotary evaporation. The mixture is washed with deionized water 2-5 times and vacuum dried to obtain a scale inhibitor. The scale inhibitor prepared by the present invention contains rich carboxyl groups, which may interfere with and inhibit the growth process of microcrystals through the chelation effect between carboxyl groups and scale-forming ions, thereby effectively preventing the formation of scale and significantly improving the scale inhibition efficiency. In the water of the double-membrane system, it can also alleviate the problem of decreased membrane flux caused by ion scaling, thereby improving the recovery rate of treated reuse water.

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

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

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

[0019] More preferably, the modifier comprises azobisisobutyronitrile, and the mass ratio of triethylamine to azobisisobutyronitrile is 1:0.01-0.1.

[0020] More preferably, the modifier comprises azobisisobutyronitrile and methyl 3-hydroxyhex-5-enoate, the mass ratio of triethylamine to azobisisobutyronitrile is 1:0.01-0.1, and the mass ratio of triethylamine to methyl 3-hydroxyhex-5-enoate is 1:1-5. The present invention further introduces a hydroxyl group into the molecular structure of the scale inhibitor to construct a stable double-electron layer structure on the surface of the poorly soluble or insoluble inorganic salt crystals, reducing collisions between crystallites, thereby preventing crystal precipitation and crystallization, further improving scale inhibition efficiency and the recovery rate of treated reuse water.

[0021] Preferably, a method for recycling and reducing wastewater from circulating cooling water in a water-cooled machine room is as follows: The sewage 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 through a booster pump for ultrafiltration. The ultrafiltration water obtained enters the intermediate water tank and enters the safety filter for filtration through the booster pump. The filtered water is then subjected to reverse osmosis treatment and the reverse osmosis water enters the water tank, and finally the treated reuse water is obtained.

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

[0023] More preferably, during the reverse osmosis treatment, the liquid enters the reverse osmosis membrane assembly through a high-pressure pump for treatment.

[0024] More preferably, in the reverse osmosis treatment, the scale inhibitor is first added and then enters the reverse osmosis membrane assembly through a high-pressure pump for treatment.

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

[0026] The present invention has the following beneficial effects because the scale inhibitor is applied to the wastewater reuse treatment and emission reduction method of the circulating cooling water of the water-cooling machine room: the present invention adopts the ultrafiltration-reverse osmosis treatment process, does not need to add complex additional equipment, does not change the components or materials of the existing treatment equipment, has high economic benefits and strong adaptability; the present invention removes most of the salts and other pollutants from the water after the wastewater is recycled and treated, and can be reused as make-up water, thereby reducing wastewater, reducing the energy consumption of the circulating water system, reducing the treatment cost of wastewater, saving water resources, achieving the effect of energy conservation and emission reduction, and having a positive social effect on promoting the development of industrial production. The scale inhibitor prepared by the present invention has a good scale inhibition effect, with a calcium ion scale inhibition rate of 70.1-95.7%, reducing the risk of reverse osmosis membrane fouling caused by ion scaling, and reducing the metal corrosion rate; applying the scale inhibitor to the wastewater reuse treatment and emission reduction method of the circulating cooling water of the water-cooling machine room helps to improve the membrane treatment efficiency, thereby increasing the water recovery rate to 58.4-91.2%, and has significant economic benefits. Therefore, the present invention is a method for recycling and reducing wastewater of circulating cooling water in a water-cooled machine room, which has good scale inhibition effect and high water recovery rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is the infrared spectrum of the scaling inhibitor. DETAILED DESCRIPTION

[0028] The present invention will be further described in detail below in conjunction with specific embodiments. The examples provided are only for illustrating the present invention and are not intended to limit the scope of the present invention. The examples provided below can serve as a guide for further improvements by those skilled in the art and are not intended to limit the present invention in any way.

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

[0030] Example 1: A method for recycling and reducing wastewater of circulating cooling water in a water-cooled machine room, comprising: 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 through a booster pump for ultrafiltration. The ultrafiltration water obtained enters the intermediate water tank and is filtered by the safety filter through the booster pump. The filtered water is then sent to the reverse osmosis membrane assembly through a high-pressure pump for treatment. The reverse osmosis water enters the water tank and is finally treated as recycled water. The hollow fiber ultrafiltration membrane system is produced by Tianjin Motian Membrane Technology Co., Ltd., and the reverse osmosis membrane assembly is produced by Guizhou Times Huitong Membrane Technology Co., Ltd. The raw water flow rate is 3m 3 / h.

[0031] Example 2: Preparation of a scale inhibitor, comprising, Under nitrogen, cinnamoyl chloride was dissolved in tetrahydrofuran, triethylamine was added and stirred evenly, 5-aminononane-5-carboxylic acid was slowly added in an ice bath, and the reaction was allowed to proceed for 1 hour. The reaction was then allowed to proceed at room temperature for 24 hours. After the reaction, azobisisobutyronitrile was added, and the mixture was allowed to react at 70°C for 12 hours. The mixture was filtered, the solvent was removed by rotary evaporation, and the mixture was washed three times with deionized water and dried under vacuum to obtain a scale inhibitor. The mass ratio of cinnamoyl chloride to triethylamine was 1:2; the 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 recycling and reducing wastewater of circulating cooling water in a water-cooled machine room, comprising: The sewage 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 through a booster pump for ultrafiltration. The ultrafiltration water obtained enters the intermediate water tank and enters the safety filter for filtration through a booster pump. A scale inhibitor is added to the filtered water, and then it enters the reverse osmosis membrane assembly through a high-pressure pump for treatment. The reverse osmosis water obtained enters the water tank and is finally treated as recycled water. The hollow fiber ultrafiltration membrane system is produced by Tianjin Motian Membrane Technology Co., Ltd., and the reverse osmosis membrane assembly is produced by Guizhou Times Huitong Membrane Technology Co., Ltd. The raw water flow rate is 3m 3 / h. The amount of scale inhibitor used is equivalent to 0.04wt% of the raw water.

[0033] Example 3: Preparation of a scale inhibitor, comprising, Under nitrogen, cinnamoyl chloride was dissolved in tetrahydrofuran, triethylamine was added and stirred evenly, 5-aminononane-5-carboxylic acid was slowly added in an ice bath, and the reaction was allowed to proceed for 1 hour. The reaction was then allowed to proceed at room temperature for 24 hours. After the reaction, azobisisobutyronitrile was added, and the mixture was allowed to react at 70°C for 12 hours. The mixture was filtered, the solvent was removed by rotary evaporation, and the mixture was washed three times with deionized water and dried under vacuum to obtain a scale inhibitor. The mass ratio of cinnamoyl chloride to triethylamine was 1:2; the 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 recycling and reducing wastewater of circulating cooling water in a water-cooled machine room, comprising: The sewage 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 through a booster pump for ultrafiltration. The ultrafiltration water obtained enters the intermediate water tank and enters the safety filter for filtration through a booster pump. A scale inhibitor is added to the filtered water, and then it enters the reverse osmosis membrane assembly through a high-pressure pump for treatment. The reverse osmosis water obtained enters the water tank and is finally treated as recycled water. The hollow fiber ultrafiltration membrane system is produced by Tianjin Motian Membrane Technology Co., Ltd., and the reverse osmosis membrane assembly is produced by Guizhou Times Huitong Membrane Technology Co., Ltd. The raw water flow rate is 3m 3 / h. The amount of scale inhibitor used is equivalent to 0.02wt% of the raw water.

[0035] Example 4: Preparation of a scale inhibitor, comprising, Under nitrogen, cinnamoyl chloride was dissolved in tetrahydrofuran, triethylamine was added and stirred evenly, 5-aminononane-5-carboxylic acid was slowly added in an ice bath, and the reaction was allowed to proceed for 1 hour. The reaction was then allowed to proceed at room temperature for 24 hours. After the reaction, azobisisobutyronitrile and methyl 3-hydroxyhex-5-enoate were added, and the mixture was allowed to react at 70°C for 12 hours. The mixture was filtered, the solvent was removed by rotary evaporation, and the mixture was washed three times with deionized water and dried under vacuum to obtain a scale inhibitor. The mass ratio of cinnamoyl chloride to triethylamine was 1:2; the amount 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-hydroxyhex-5-enoate was 1:2.

[0036] A method for recycling and reducing wastewater of circulating cooling water in a water-cooled machine room, comprising: The sewage 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 through a booster pump for ultrafiltration. The ultrafiltration water obtained enters the intermediate water tank and enters the safety filter for filtration through a booster pump. A scale inhibitor is added to the filtered water, and then it enters the reverse osmosis membrane assembly through a high-pressure pump for treatment. The reverse osmosis water obtained enters the water tank and is finally treated as recycled water. The hollow fiber ultrafiltration membrane system is produced by Tianjin Motian Membrane Technology Co., Ltd., and the reverse osmosis membrane assembly is produced by Guizhou Times Huitong Membrane Technology Co., Ltd. The raw water flow rate is 3m 3 / h. The amount of scale inhibitor used is equivalent to 0.04wt% of the raw water.

[0037] Example 5: Preparation of a scale inhibitor, comprising, Under nitrogen, cinnamoyl chloride was dissolved in tetrahydrofuran, triethylamine was added and stirred evenly, 5-aminononane-5-carboxylic acid was slowly added in an ice bath, and the reaction was allowed to proceed for 1 hour. The reaction was then allowed to proceed at room temperature for 24 hours. After the reaction, azobisisobutyronitrile and methyl 3-hydroxyhex-5-enoate were added, and the mixture was allowed to react at 70°C for 12 hours. The mixture was filtered, the solvent was removed by rotary evaporation, and the mixture was washed three times with deionized water and dried under vacuum to obtain a scale inhibitor. The mass ratio of cinnamoyl chloride to triethylamine was 1:2; the amount 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-hydroxyhex-5-enoate was 1:2.

[0038] A method for recycling and reducing wastewater of circulating cooling water in a water-cooled machine room, comprising: The sewage 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 through a booster pump for ultrafiltration. The ultrafiltration water obtained enters the intermediate water tank and enters the safety filter for filtration through a booster pump. A scale inhibitor is added to the filtered water, and then it enters the reverse osmosis membrane assembly through a high-pressure pump for treatment. The reverse osmosis water obtained enters the water tank and is finally treated as recycled water. The hollow fiber ultrafiltration membrane system is produced by Tianjin Motian Membrane Technology Co., Ltd., and the reverse osmosis membrane assembly is produced by Guizhou Times Huitong Membrane Technology Co., Ltd. The raw water flow rate is 3m 3 / h. The amount of scale inhibitor used is equivalent to 0.02wt% of the raw water.

[0039] Comparative Example 1: Preparation of a scale inhibitor, comprising, Under nitrogen, 5-aminononane-5-carboxylic acid was dissolved in tetrahydrofuran, triethylamine was added and stirred, and the mixture was allowed to react at room temperature for 24 hours. After the reaction, azobisisobutyronitrile was added, and the mixture was allowed to react at 70°C for 12 hours. The mixture was then filtered, the solvent removed by rotary evaporation, and the mixture was washed three times with deionized water and dried under vacuum to obtain a scale inhibitor. The 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 recycling and reducing wastewater of circulating cooling water in a water-cooled machine room, comprising: The sewage 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 through a booster pump for ultrafiltration. The ultrafiltration water obtained enters the intermediate water tank and enters the safety filter for filtration through a booster pump. A scale inhibitor is added to the filtered water, and then it enters the reverse osmosis membrane assembly through a high-pressure pump for treatment. The reverse osmosis water obtained enters the water tank and is finally treated as recycled water. The hollow fiber ultrafiltration membrane system is produced by Tianjin Motian Membrane Technology Co., Ltd., and the reverse osmosis membrane assembly is produced by Guizhou Times Huitong Membrane Technology Co., Ltd. The raw water flow rate is 3m 3 / h. The amount of scale inhibitor used is equivalent to 0.04wt% of the raw water.

[0041] Comparative Example 2: Preparation of a scale inhibitor, comprising, Under nitrogen, triethylamine was added to tetrahydrofuran, stirred evenly, and the mixture was allowed to react in an ice bath for 1 hour, then at room temperature for 24 hours. After the reaction, azobisisobutyronitrile and methyl 3-hydroxyhex-5-enoate were added, and the mixture was allowed to react at 70°C for 12 hours. The mixture was filtered, the solvent was removed by rotary evaporation, and the mixture was washed three times with deionized water. The scale inhibitor was dried under vacuum to obtain the product. 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-hydroxyhex-5-enoate was 1:2.

[0042] A method for recycling and reducing wastewater of circulating cooling water in a water-cooled machine room, comprising: The sewage 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 through a booster pump for ultrafiltration. The ultrafiltration water obtained enters the intermediate water tank and enters the safety filter for filtration through a booster pump. A scale inhibitor is added to the filtered water, and then it enters the reverse osmosis membrane assembly through a high-pressure pump for treatment. The reverse osmosis water obtained enters the water tank and is finally treated as recycled water. The hollow fiber ultrafiltration membrane system is produced by Tianjin Motian Membrane Technology Co., Ltd., and the reverse osmosis membrane assembly is produced by Guizhou Times Huitong Membrane Technology Co., Ltd. The raw water flow rate is 3m 3 / h. The amount of scale inhibitor used is equivalent to 0.04wt% of the raw water.

[0043] Experimental example: 1. Material characterization The scale inhibitor prepared in Example 2 was purified and vacuum dried, and a sample was prepared by potassium bromide tablet coating method. The sample was analyzed by Fourier transform infrared spectrometer at 400-4000 cm -1 Infrared scanning is performed within the wavelength range with a test resolution of 4.0cm -1 , take the average of 32 times.

[0044] Figure 1 This is the infrared spectrum of the scale inhibitor. 3400cm -1 The absorption peak of OH appears near 2900 cm -1 The absorption peak of CH appears near 1690 cm -1 The absorption peak of C=O appears near 1630cm -1 A C=C absorption peak appears nearby.

[0045] 2. Calcium ion scale inhibition rate Calcium ion content was determined using 100 mL of filtered water and 100 mL of treated recycled water samples from Examples 1-5 and Comparative Examples 1-2, respectively, for the method for reuse, treatment, and emission reduction of circulating cooling water in a water-cooled machine room. The calcium ion content of the filtered water sample was designated as C1, and the calcium ion content of the treated recycled water sample was designated 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 can be seen from Table 1, the scale inhibition rate of Examples 2-3 of the present invention is higher than that of Example 1 because, in Example 2-3, cinnamoyl chloride and 5-aminononane-5-carboxylic acid are first reacted, and then a polymerization reaction is carried out under the action of azobisisobutyronitrile to obtain a scale inhibitor, and then the scale inhibitor is applied to the method for recycling and reducing the wastewater of the circulating cooling water in the water-cooling machine room, while Example 1 does not use a scale inhibitor in the method for recycling and reducing the wastewater of the circulating cooling water in the water-cooling machine 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 does not use cinnamoyl chloride and 5-aminononane-5-carboxylic acid to react, but only 5-aminononane-5-carboxylic acid is polymerized under the action of azobisisobutyronitrile to obtain the scale inhibitor. This shows that applying the scale inhibitor prepared by the present invention to the method for recycling and reducing the wastewater of the circulating cooling water in the water-cooling machine room helps to improve the scale inhibition effect.

[0048] The scale inhibition rate of Example 4-5 of the present invention is higher than that of Example 2 because, in the preparation of the scale inhibitor, Example 4-5 further adds 3-hydroxyhex-5-enoic acid methyl ester to carry out a polymerization reaction to obtain the scale inhibitor; the scale inhibition rate of Example 4-5 of the present invention is higher than that of Comparative Example 2 because, in the preparation of the scale inhibitor, Comparative Example 2 only uses 3-hydroxyhex-5-enoic acid methyl ester to carry out a polymerization reaction 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 in the water-cooled room circulating cooling water wastewater reuse treatment and emission reduction method is different. This shows that the present invention first uses cinnamoyl chloride and 5-aminononane-5-carboxylic acid to react, and then carries out a polymerization reaction with 3-hydroxyhex-5-enoic acid methyl ester under the action of azobisisobutyronitrile to obtain the scale inhibitor, and then applies the prepared scale inhibitor to the water-cooled room circulating cooling water wastewater reuse treatment and emission reduction method, which helps to further improve the scale inhibition effect.

[0049] 3. Recovery rate of treated recycled water The raw water inflow and treated reuse water outflow were measured for each of Examples 1-5 and Comparative Examples 1-2 at 5 hours of raw water treatment. The raw water inflow was recorded as M1, and the treated reuse water outflow was recorded as M2. The treated reuse water recovery rate (%) = M2 / M1 × 100%.

[0050] Table 2 Recovery rate (%)

[0051] As shown in Table 2, the recovery rate of Example 2-3 of the present invention is higher than that of Example 1, because Example 2-3 first uses cinnamoyl chloride and 5-aminononane-5-carboxylic acid to react, and then performs a polymerization reaction under the action of azobisisobutyronitrile to obtain a scale inhibitor, and then applies the scale inhibitor to the wastewater reuse treatment and emission reduction method of the circulating cooling water of the water-cooling machine room, while Example 1 does not use a scale inhibitor in the wastewater reuse treatment and emission reduction method of the circulating cooling water of the water-cooling machine room; the recovery rate of Example 2 is higher than that of Example 3, because the amount of scale inhibitor used is different; the recovery rate of Example 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 does not use cinnamoyl chloride and 5-aminononane-5-carboxylic acid to react, and only 5-aminononane-5-carboxylic acid is polymerized under the action of azobisisobutyronitrile to obtain a scale inhibitor. This shows that applying the scale inhibitor prepared by the present invention to the wastewater reuse treatment and emission reduction method of the circulating cooling water of the water-cooling machine room helps to improve the recovery rate of the treated reused water.

[0052] The recovery rate of Examples 4-5 of the present invention is higher than that of Example 2 because, in the preparation of the scale inhibitor, Example 4-5 further adds 3-hydroxyhex-5-enoic acid methyl ester to carry out a polymerization reaction to obtain the scale inhibitor; the recovery rate of Examples 4-5 of the present invention is higher than that of Comparative Example 2 because, in the preparation of the scale inhibitor, Comparative Example 2 only uses 3-hydroxyhex-5-enoic acid methyl ester to carry out a polymerization reaction 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 in the water-cooled room circulating cooling water wastewater reuse treatment and emission reduction method is different. This shows that the present invention first uses cinnamoyl chloride and 5-aminononane-5-carboxylic acid to react, then carries out a polymerization reaction with 3-hydroxyhex-5-enoic acid methyl ester under the action of azobisisobutyronitrile to obtain the scale inhibitor, and then applies the prepared scale inhibitor to the water-cooled room circulating cooling water wastewater reuse treatment and emission reduction method, which helps to further improve the recovery rate of the treated reused water.

[0053] The conventional operations in the operating steps of the present 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 description of the technical solutions of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, supplements or similar substitutions made within the scope of the principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for recycling and reducing wastewater from circulating cooling water in a water-cooled machine room, comprising: The raw water is sequentially filtered through a hollow fiber ultrafiltration membrane system, a security filter, and reverse osmosis to obtain treated reuse water; The raw water flow rate is 1-5m 3 / h.

2. The method for recycling and reducing wastewater of circulating cooling water in a water-cooled machine room according to claim 1 is characterized in that: During the reverse osmosis treatment process, a scaling inhibitor is first added, and then the reverse osmosis membrane assembly is used for treatment.

3. The method for recycling and reducing wastewater of circulating cooling water in a water-cooled machine room according to claim 2 is characterized in that: The usage amount of the scale inhibitor is 0.02-0.04 wt% of the raw water.

4. The method for recycling and reducing wastewater of circulating cooling water in a water-cooled machine room according to claim 2 is characterized in that: In the preparation of the scale inhibitor, cinnamoyl 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.

5. The method for recycling and reducing wastewater of circulating cooling water in a water-cooled machine room according to claim 4 is characterized in that: The mass ratio of the cinnamoyl chloride to triethylamine is 1:1-5.

6. The method for recycling and reducing wastewater of circulating cooling water in a water-cooled machine room according to claim 4 is characterized in that: The usage ratio of triethylamine and tetrahydrofuran is 1g:5-20mL.

7. The method for recycling and reducing wastewater of circulating cooling water in a water-cooled machine room according to claim 4 is characterized in that: The mass ratio of the triethylamine to 5-aminononane-5-carboxylic acid is 1:1-3.

8. The method for recycling and reducing wastewater of circulating cooling water in a water-cooled machine room according to claim 4 is characterized in that: The modifier comprises azobisisobutyronitrile, and the mass ratio of triethylamine to azobisisobutyronitrile is 1:0.01-0.

1.

9. The method for recycling and reducing wastewater of circulating cooling water in a water-cooled machine room according to claim 4, characterized in that: The free radical polymerization reaction temperature is 70-90°C.

10. The method for recycling and reducing wastewater of circulating cooling water in a water-cooled machine room according to claim 4, characterized in that: The free radical polymerization reaction time is 8-24h.

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