Pipeline type reclaimed water treatment device and treatment method

Abstract

The invention discloses a pipeline type reclaimed water treatment device and a treatment method, and relates to the technical field of water treatment.The treatment device comprises a water inlet pipeline, a gas inlet pipeline and a water outlet pipeline, a plurality of second branch pipes are connected between the water inlet pipeline and the water outlet pipeline, the number of the second branch pipes is larger than or equal to 2, and the second branch pipes are communicated with the water inlet pipeline. The second branch pipes are connected in parallel; each second branch pipe is provided with a gas-liquid mixer and a back pressure valve, and the gas-liquid mixers are located at the upstream of the back pressure valves in the flow path of the second branch pipes; the treatment device further comprises first branch pipes with the number equal to that of the second branch pipes, the gas-liquid mixers on the second branch pipes are connected with the gas inlet pipeline through the independent first branch pipes, the treatment method is used for adjusting the pH value of the water body to be treated based on the treatment device, and the scheme can effectively solve the problems that the pH value of the treated water body is unstable, and the needed pipeline is long. And the device also has the characteristics of being beneficial to the operation safety of the device and reducing the setting cost and the maintenance cost of the device.

Description

Technical Field

[0001] The present invention relates to the technical field of water treatment, and particularly to a pipeline type intermediate water treatment device and a treatment method thereof. Background Art

[0002] To protect the environment and improve the utilization rate of resources, the sewage generated by construction activities usually contains sand and gravel and the water body is usually alkaline. In the existing treatment methods, through screening and multi-stage sedimentation means, the sand and gravel in the sewage can be separated according to particle size at different positions in the treatment process, and the pH value of the settled sewage can be adjusted, and intermediate water can be obtained for further utilization. To avoid using strong acids, reduce the difficulty of material management and the difficulty of protecting the treatment system, the method of using carbon dioxide to adjust the pH value of the water body is an environmentally friendly, safe, economical method that can achieve precise adjustment of acidity and alkalinity.

[0003] The existing systems for adjusting the pH value of water bodies based on carbon dioxide usually include an open system and a closed system. The open system mostly uses a mixing tank and a reaction tank. Specifically, the water body and carbon dioxide are mixed in the mixing tank and then diverted to the reaction tank for further reaction, or an aeration tank is used, and the method of directly injecting carbon dioxide into the water body through an aeration device arranged in the aeration tank is adopted; the closed system means that the processes of mixing carbon dioxide and water body and reacting carbon dioxide and water body are all located in a closed space. Compared with the open system, the above-mentioned closed space can effectively improve the utilization rate of carbon dioxide and realize the reuse of excess carbon dioxide to avoid environmental emissions.

[0004] The above-mentioned closed system usually includes a gas source module, a mixing and reaction module, and a control module. The gas source module is used to provide carbon dioxide for the mixing and reaction module, the mixing and reaction module is used to realize the mixing of water and gas and provide a reaction process, and the control module dynamically adjusts the injection amount of carbon dioxide / water body flow rate according to the pH value monitoring result to realize the automatic operation of the system.

[0005] Adjusting the pH value of water bodies based on carbon dioxide has the characteristics of high safety, good environmental friendliness, high economy, and high-precision controllability of the adjustment result. However, during the use of the pipeline type adjustment system, there are still problems such as fluctuations in pH value, relatively long required pipelines, and damage to pipe fittings by calcium carbonate by-products. Summary of the Invention

[0006] In view of the above-mentioned related problems of the pipeline type adjustment system, the present invention provides a pipeline type intermediate water treatment device and a treatment method thereof. This solution can effectively solve the problems of unstable pH value of the treated water body and relatively long required pipelines. Under the same water treatment volume, it also has the advantages of being beneficial to the operation safety of the device and being beneficial to reducing the installation cost and maintenance cost of the device.

[0007] In view of the above problems, the pipeline type intermediate water treatment device and treatment method provided by the present invention solve the problems through the following technical key points: The pipeline type intermediate water treatment device includes a water inlet pipeline, an air inlet pipeline, and a water outlet pipeline. A plurality of second branch pipes are connected between the water inlet pipeline and the water outlet pipeline. The number of the second branch pipes is greater than or equal to 2, and the second branch pipes are in a parallel relationship with each other;

[0008] An air-liquid mixer and a back pressure valve are provided on each second branch pipe. In the flow path of the second branch pipe, the air-liquid mixer is located upstream of the back pressure valve;

[0009] It further includes a first branch pipe with the same number as the second branch pipes. The air-liquid mixers on each second branch pipe are connected to the air inlet pipeline through separate first branch pipes.

[0010] In this solution, the water inlet pipeline is used to introduce the water to be treated into the treatment device, the air inlet pipeline is used to introduce carbon dioxide into the treatment device, the second branch pipe is used for connecting the water inlet pipeline and the water outlet pipeline, and the first branch pipe is used to introduce carbon dioxide into the air-liquid mixers of each second branch pipe to achieve the mixing of carbon dioxide and the water to be treated.

[0011] This solution is different from the prior art in that a back pressure valve is used to increase the internal pressure in the second branch pipe, so as to increase the dissolution pressure environment of carbon dioxide and improve the dissolution efficiency of carbon dioxide in the water to be treated. The improvement of the above dissolution efficiency can, firstly, reduce the pipeline length for realizing the pH value adjustment. At the same time, it can effectively avoid the formation of a gas-liquid two-phase flow in the pipe section due to the untimely dissolution of carbon dioxide, and the accumulation of carbon dioxide at the positions such as pipe section turning or pipe fittings, resulting in an air blockage phenomenon, causing fluctuations in the flow rate in the second branch pipe and fluctuations in the pH value adjustment result.

[0012] This solution is different from the prior art. In any second branch pipe, the fluid flow downstream of the gas-liquid mixer is a process in which carbon dioxide participates in pH value adjustment. For the water body to be treated from the inlet pipeline, since it is branched through the second branch pipe, to meet the flow demand of the water body to be treated, compared with single-path treatment (the inlet pipeline and the outlet pipeline are directly connected continuous pipelines), the flow rate in a single second branch pipe is smaller than that of the inlet pipeline and the outlet pipeline. Therefore, a smaller pipe diameter can be used for the second branch pipe, and fittings connected to the second branch pipe can also use a smaller nominal diameter. Therefore, for the carbon dioxide dissolution environment formed by the back pressure valve on each second branch pipe (considering the treatment efficiency, some high-alkalinity waters may require a pressure environment greater than 0.5 Mpa to be formed through the back pressure valve), the above smaller pipe diameter and nominal diameter are beneficial to safely increasing the dissolution environment pressure, ensuring the safe operation of the device (under the same wall thickness, a pipe with a smaller diameter or a fitting with a smaller nominal diameter has greater pressure resistance), and reducing the device installation cost and maintenance cost (for pipes and fittings with the same pressure resistance, when the pipe diameter is larger or the nominal diameter of the fitting is larger, the installation and maintenance costs increase significantly). In this application, a preferable implementation method is to use a spring-type back pressure valve with an adjustable pressure range of (0.3 - 0.6 Mpa).

[0013] Regarding the generation of calcium carbonate by-products during the operation of the treatment device, after the by-products scale on the pipeline (scale inhibitors can also be added to the water body to be treated regularly) and wear the back pressure valve spool, the device will have the characteristic of a high maintenance frequency. This solution is different from the prior art. By setting the connection between the inlet pipeline and the outlet pipeline to be completed through two or more second branch pipes, during maintenance, only some second branch pipes are maintained at the same time period, while other second branch pipes are used to continue treating the water body to be treated. This can make the treatment device have the characteristic of being able to continuously complete the pH value adjustment of the water body to be treated. In this application, the pipeline carrying the gas-liquid mixer and the back pressure valve on the second branch pipe needs to be isolated from the treatment device. The specific isolation method can be to connect cut-off valves at both ends of this pipe section.

[0014] As a further technical solution of the pipeline type medium water treatment device:

[0015] A first flow regulating valve and a first flow meter are provided on each second branch pipe. The first flow regulating valve is used to adjust the water flow rate on the second branch pipe, and the first flow meter is used to detect the water flow rate on the second branch pipe;

[0016] A second flow meter and a second flow regulating valve are provided on each first branch pipe. The second flow meter is used to detect the gas flow rate on the first branch pipe, and the second flow regulating valve is used to adjust the gas flow rate on the first branch pipe.

[0017] In the above solution, the first flowmeter is used to measure the flow rate of the water to be treated on the second branch pipe, and the second flowmeter is used to measure the flow rate of carbon dioxide gas on the first branch pipe. By calibrating the corresponding fluid flow rate and cooperating with the corresponding flow regulating valve to adjust the corresponding fluid flow rate, the water to be treated and carbon dioxide can be accurately proportioned and mixed, while ensuring the treatment effect of the water to be treated, improving the utilization rate of carbon dioxide and reducing the recovery and treatment volume of surplus carbon dioxide.

[0018] Preferably, both the first flow regulating valve and the second flow regulating valve adopt automatic flow regulating valves with actuators, which are used to achieve: pipeline differences between the second branch pipes and mixing effect differences of the gas-liquid mixers on each second branch pipe will result in different water treatment efficiencies (aeration efficiencies) for different second branch pipes. In this application, the control device can, according to the water treatment efficiencies of each second branch pipe, specifically control the water flow rate in each second branch pipe and the gas flow rate in each first branch pipe. By adjusting the water flow rate and the mixing ratio of the water flow rate and carbon dioxide, each second branch pipe can complete the treatment of the water to be treated under efficient and economical working conditions. In specific applications, if, for reasons such as scaling, the efficiency of the second branch pipe changes at different times, those skilled in the art can dynamically adjust the flow rate / mixing ratio based on the monitoring results of the pH value of the treated water.

[0019] An axial flow pump is provided on each second branch pipe, and the axial flow pump is located upstream of the gas-liquid mixer.

[0020] In the above solution, the axial flow pump is used to separately establish the dissolved pressure environment of the gas in each second branch pipe. Not only can the internal pressure of each second branch pipe be independently controlled, but also the above-mentioned dissolved pressure environment is not affected by the head of the inlet water pump at the front end of the inlet pipeline, nor by the pressure loss caused by a pre-filter on the inlet pipeline. In specific applications, this treatment device can be used as a complete set of equipment and flexibly applied to the water reuse system of each mixing station.

[0021] A reaction tank is provided on each second branch pipe, and the reaction tank is located between the gas-liquid mixer and the back pressure valve.

[0022] In this solution, the reaction tank, as a pressure vessel connected to the second branch pipe, is used to temporarily store the water mixed with carbon dioxide. While shortening the pipeline length of the second branch pipe, it enables these waters to have sufficient pressure retention time for the dissolved carbon dioxide to fully participate in pH value adjustment.

[0023] The reaction tank includes a pressure-bearing shell, an anti-corrosion lining layer provided on the inner wall of the pressure-bearing shell, a porous support plate provided inside the pressure-bearing shell and located at the bottom side of the pressure-bearing shell, a stuffing box supported on the porous support plate, and a water distributor installed inside the pressure-bearing shell and located below the porous support plate;

[0024] The pipeline between the gas-liquid mixer and the reaction tank is connected to the water distributor, and the connection position of the pipeline between the reaction tank and the back-pressure valve on the reaction tank is above the stuffing box.

[0025] This solution provides a specific structural form of the reaction tank, that is: the reaction tank includes a pressure-bearing shell as the main structure and the pressure-bearing boundary, and an anti-corrosion lining layer as the protective layer of the pressure-bearing shell. The anti-corrosion lining layer is preferably made of HDPE, PTFE plate or other plastics that are acid and alkali resistant, have a smooth surface, and are not prone to calcium carbonate scaling. The porous support plate can also be made of a plastic plate with sufficient strength. The porous support plate is supported on the pressure-resistant shell by a 304 stainless steel support ring. The stuffing box is used to evenly distribute the flow field in the pressure-bearing shell and form a sedimentation area for calcium carbonate by-products. The water distributor is used to evenly distribute the water inlet flow at each position on the bottom side of the porous support plate. When this treatment device is working, the fluid from the gas-liquid mixer is evenly injected into the space below the porous support plate through the water distributor, then passes upward through the porous support plate and enters the stuffing box, and then further passes through the second branch pipe and the back-pressure valve from the water outlet above the stuffing box, and is led to the outlet pipeline. To facilitate the installation and maintenance of the water distributor and the stuffing box, both the bottom and the top of the reaction tank have heads that are detachable relative to the tank body. The above-provided structural form of the reaction tank, with the provided stuffing box and water distributor, can evenly distribute the flow field in the reaction tank, so that the water body can have a stable residence time in the reaction tank for the dissolved carbon dioxide to fully participate in the regulation of the water body pH value. At the same time, the reaction tank itself has good anti-corrosion and anti-scaling capabilities. At the same time, the stuffing box can be used for calcium carbonate sedimentation, so that the by-products are concentrated and retained in the reaction tank, reducing their impact on the downstream back-pressure valve spool (the main impact is that when the upstream pressure of the back-pressure valve is insufficient and the back-pressure valve spool closes, calcium carbonate becomes the abrasive between the spool and the valve seat, resulting in rapid wear of the mating surface between the spool and the valve seat).

[0026] In the reaction tank, there is a gas storage space above the connection position of the pipeline between the reaction tank and the back-pressure valve on the reaction tank;

[0027] It also includes a detection device for detecting the pressure difference between the inlet and outlet fluids of the reaction tank.

[0028] The above solution aims to define the position of the fluid outlet on the reaction tank relative to the top of the reaction tank, that is, the connection position of the pipeline between the reaction tank and the back pressure valve on the reaction tank is below the top of the inner space of the reaction tank. There is a gas storage space above the outlet pipeline interface at this position. This solution aims to achieve: when the pressure fluctuates on the inlet side of the reaction tank, the gas stored in the gas storage space can be used to expand or compress to stabilize the air pressure in the reaction tank. While stabilizing the pH value adjustment ability, it can avoid the frequent movement of the valve core of the back pressure valve, and under the influence of calcium carbonate, the valve core and valve seat are accelerated to be damaged. The above detection device is used to indicate the pressure loss when the fluid flows through the reaction tank, that is, the detection result of the detection device can be used to indicate whether maintenance is required for the stuffing box and the stainless steel middle drain as a water distributor.

[0029] In a specific embodiment, the gas stored in the gas storage space serves as a buffer gas for maintaining pressure stability. For example, nitrogen that is hardly soluble in water under pressure is used. This buffer gas can be injected into the reaction tank through an exhaust pipe connected to the reaction tank.

[0030] It also includes a gas sensor and a safety valve installed on the top of the reaction tank. The gas sensor is used to detect the composition of the gas in the gas storage space.

[0031] In this solution, the safety valve serves as a safety accessory on the top of the reaction tank to avoid overpressure inside the reaction tank; the gas sensor is used to obtain the gas in the gas storage space sufficiently. For example, by detecting the content of carbon dioxide in the gas phase of the gas storage space, it can be determined whether the carbon dioxide introduced through the first branch pipe is excessive, avoiding situations where, when the carbon dioxide is excessive, not only is it necessary to maintain the liquid level in the reaction tank by exhausting gas, but also the exhausted carbon dioxide needs to be emptied or further absorbed, increasing the environmental burden and water treatment cost.

[0032] It also includes an exhaust pipe and a safety valve installed on the top of the reaction tank. The exhaust pipe is used to discharge the gas in the gas storage space.

[0033] In this solution, the safety valve serves as a safety accessory on the top of the reaction tank to avoid overpressure inside the reaction tank; the exhaust pipe is used to discharge the gas at the top of the reaction tank when the carbon dioxide is excessive to maintain the liquid level in the reaction tank and improve the utilization rate of the internal space of the reaction tank. In specific applications, the exhaust pipe is a Y-shaped pipe. Among the three pipe orifices of the exhaust pipe, one pipe orifice is connected to the reaction tank, and among the other two pipe orifices, one pipe orifice serves as the exhaust port for the reaction tank to exhaust gas outward, and the other pipe orifice serves as the injection port for injecting nitrogen into the reaction tank through the exhaust pipe. As a person skilled in the art, at least two control valves should be connected to the exhaust pipe to respectively control the conduction states between the reaction tank and different pipe orifices.

[0034] The gas-liquid mixer includes a jet mixer and a static mixer. The static mixer is arranged on the outlet side of the jet mixer. The connection position of the first branch pipe on the gas-liquid mixer is located on the jet mixer.

[0035] The static mixer is provided with spoiler plates for making the fluid form a turbulent flow pattern.

[0036] It further includes a control device for controlling the water flow rate in each second branch pipe and the gas flow rate in each first branch pipe.

[0037] The above solution provides a specific implementation form of the gas-liquid mixer. The jet mixer serves as a mixer that forms a negative pressure based on the water flow to suck in carbon dioxide (which can be assisted by the carbon dioxide gas source pressure to ensure the carbon dioxide injection volume) and realizes the mixing of carbon dioxide and water. The mixing effect of this mixer is affected by the water flow rate in the mixer. Since there is a back pressure valve at its subsequent stage and according to the treatment requirements, the water flow rate at its previous stage may be unstable. When the flow rate is small, there are problems such as poor mixing efficiency and affecting the carbon dioxide dissolution rate. Based on this, it is further set to also include a static mixer. In the process of the gas-liquid mixer, the primary mixing of gas and liquid is first completed by the jet mixer, and then it enters the static mixer to complete further mixing. While reducing the pressure loss, it can effectively ensure the carbon dioxide dissolution rate. The above control device is used to control the flow rate ratio of the water to be treated and carbon dioxide to achieve the purpose of ensuring the control accuracy of the carbon dioxide injection volume.

[0038] This solution also relates to a pipeline-type intermediate water treatment method, which adjusts the pH value of the water to be treated with carbon dioxide and is implemented based on the treatment device described in any one of the above.

[0039] In this method, the water to be treated from the inlet pipeline is distributed to each second branch pipe, and carbon dioxide from the inlet gas pipeline is introduced into the gas-liquid mixer through the first branch pipe to realize the gas-liquid mixing of the water to be treated and carbon dioxide. Among them, the water flow rate in any second branch pipe and the carbon dioxide flow rate introduced into this second branch pipe have a set ratio. During the pH value adjustment process, the internal pressure of the corresponding second branch pipe is established and maintained through each back pressure valve. This treatment method is the treatment method for adjusting the pH value of the water to be treated when the above treatment system is applied.

[0040] The present invention has the following beneficial effects:

[0041] This solution is different from the prior art. By using a backpressure valve to increase the internal pressure in the second branch pipe, the dissolution efficiency of carbon dioxide in the water to be treated is improved, the pipeline length for achieving the pH value adjustment can be reduced, and the formation of a gas-liquid two-phase flow in the pipe section due to the untimely dissolution of carbon dioxide can be effectively avoided. Carbon dioxide accumulation may occur at positions such as pipe section bends or pipe fittings, resulting in gas blockage phenomena, causing fluctuations in the flow rate in the second branch pipe and fluctuations in the pH value adjustment result, etc.

[0042] This solution is different from the prior art. On any second branch pipe, the fluid flow downstream of the gas-liquid mixer is the process in which carbon dioxide participates in the pH value adjustment. To meet the flow rate requirements of the water to be treated, the second branch pipe can adopt a smaller pipe diameter, and the pipe fittings connected to the second branch pipe can also adopt a smaller nominal diameter. Therefore, for the carbon dioxide dissolution environment formed by the backpressure valve on each second branch pipe, the above smaller pipe diameter and nominal diameter are beneficial to safely increasing the dissolution environment pressure, ensuring the safe operation of the device, and reducing the device installation cost and maintenance cost.

[0043] This solution is different from the prior art. By setting the connection between the water inlet pipe and the water outlet pipe to be completed through two or more second branch pipes, during maintenance, only some second branch pipes are maintained in the same time period, while other second branch pipes are used to continue the treatment of the water to be treated. This can make the treatment device have the characteristic of being able to continuously complete the pH value adjustment of the water to be treated. Description of the Drawings

[0044] Figure 1 It is the equipment layout diagram of a specific embodiment of the pipeline type intermediate water treatment device described in this solution;

[0045] Figure 2 It is the cross-sectional view of the reaction tank in a specific embodiment of the pipeline type intermediate water treatment device described in this solution. The reference numerals in the drawings are respectively: 1, water inlet pipe; 2, water outlet pipe; 3, first branch pipe; 4, gas inlet pipe; 5, second branch pipe; 6, axial flow pump; 7, first flow regulating valve; 8, first flowmeter; 9, gas-liquid mixer; 10, second flowmeter; 11, second flow regulating valve; 12, backpressure valve; 13, pre-filter; 14, reaction tank; 15, gas sensor; 16, safety valve; 17, pressure-bearing housing; 18, stuffing box; 19, anti-corrosion lining; 20, porous support plate; 21, water distributor; 22, gas storage space; 23, exhaust pipe. Detailed Description of the Embodiment

[0046] The present invention will be further described in detail below in conjunction with the embodiments, but the present invention is not limited to the following embodiments:

[0047] Embodiment 1:

[0048] AsFigure 1 and Figure 2 As shown in Figure 2 , the pipeline type intermediate water treatment device includes a water inlet pipeline 1, an air inlet pipeline 4 and a water outlet pipeline 2. A plurality of second branch pipes 5 are connected between the water inlet pipeline 1 and the water outlet pipeline 2. The number of the second branch pipes 5 is greater than or equal to 2, and the second branch pipes 5 are in a parallel relationship with each other;

[0049] An air-liquid mixer 9 and a back pressure valve 12 are arranged on each second branch pipe 5. In the flow path of the second branch pipe 5, the air-liquid mixer 9 is located upstream of the back pressure valve 12;

[0050] It also includes first branch pipes 3 with the same number as the second branch pipes 5. The air-liquid mixers 9 on each second branch pipe 5 are connected to the air inlet pipeline 4 through separate first branch pipes 3.

[0051] In this solution, the water inlet pipeline 1 is used to introduce the water to be treated into the treatment device, the air inlet pipeline 4 is used to introduce carbon dioxide into the treatment device, the second branch pipe 5 is used for connecting the water inlet pipeline 1 and the water outlet pipeline 2, and the first branch pipe 3 is used to introduce carbon dioxide into the air-liquid mixer 9 of each second branch pipe 5 to realize the mixing of carbon dioxide and the water to be treated.

[0052] This solution is different from the prior art. The back pressure valve 12 is used to increase the internal pressure in the second branch pipe 5, so as to increase the dissolution pressure environment of carbon dioxide and improve the dissolution efficiency of carbon dioxide in the water to be treated. The improvement of the above dissolution efficiency can, firstly, reduce the pipeline length for realizing the pH value adjustment. At the same time, it can effectively avoid the formation of gas-liquid two-phase flow in the pipe section due to the untimely dissolution of carbon dioxide, and the accumulation of carbon dioxide at the positions such as pipe section turning or pipe fittings, resulting in gas blockage phenomenon, causing fluctuations in the flow rate in the second branch pipe 5 and fluctuations in the pH value adjustment result, etc.

[0053] This solution is different from the prior art. In any second branch pipe 5, the fluid flow path downstream of the air-liquid mixer 9 is the flow path for carbon dioxide to participate in the pH value adjustment. For the water to be treated from the water inlet pipeline 1, due to the diversion through the second branch pipe 5, in order to meet the flow rate requirement of the water to be treated, a single second branch pipe 5 has a smaller flow rate relative to the water inlet pipeline 1 and the water outlet pipeline 2. Therefore, the second branch pipe 5 can adopt a smaller pipe diameter, and the pipe fittings connected to the second branch pipe 5 can also adopt a smaller nominal diameter. Therefore, for the carbon dioxide dissolution environment formed by the back pressure valve 12 on each second branch pipe 5 (considering the treatment efficiency, some high-alkalinity waters may need to form a pressure environment greater than 0.5 Mpa through the back pressure valve 12), the above smaller pipe diameter and nominal diameter are beneficial to safely increasing the dissolution environment pressure, ensuring the safe operation of the device, and reducing the device setting cost and maintenance cost. In this application, a preferred implementation method is to adopt a spring type back pressure valve 12 with an adjustable pressure range of (0.3 - 0.6 Mpa).

[0054] When the processing device generates calcium carbonate by-products during operation, the scaling of these by-products on the pipeline (or scale inhibitors can be added to the water to be treated regularly) and the wear of the valve core of the back-pressure valve 12 will result in the characteristic of high maintenance frequency of this device. The difference between this solution and the prior art is that the connection between the water inlet pipe 1 and the water outlet pipe 2 is completed through two or more second branch pipes 5. During maintenance, only some of the second branch pipes 5 are maintained at the same time period, while the other second branch pipes 5 are used to continue the treatment of the water to be treated, so that this treatment device can continuously adjust the pH value of the water to be treated. In this application, the pipelines carrying the gas-liquid mixer 9 and the back-pressure valve 12 on the second branch pipe 5 need to be isolated from this treatment device. The specific isolation method can be to connect cut-off valves at both ends of this pipe section.

[0055] Embodiment 2:

[0056] This embodiment is further refined on the basis of Embodiment 1:

[0057] A first flow regulating valve 7 and a first flow meter 8 are provided on each second branch pipe 5. The first flow regulating valve 7 is used to adjust the water flow on the second branch pipe 5, and the first flow meter 8 is used to detect the water flow on the second branch pipe 5;

[0058] A second flow meter 10 and a second flow regulating valve 11 are provided on each first branch pipe 3. The second flow meter 10 is used to detect the gas flow on the first branch pipe 3, and the second flow regulating valve 11 is used to adjust the gas flow on the first branch pipe 3.

[0059] In the above solution, the first flow meter 8 is used to measure the water flow of the water to be treated on the second branch pipe 5, and the second flow meter 10 is used to measure the carbon dioxide gas flow on the first branch pipe 3. By calibrating the corresponding fluid flow and cooperating with the corresponding flow regulating valve to achieve the adjustment of the corresponding fluid flow, the water to be treated and carbon dioxide can be accurately proportioned and mixed, while ensuring the treatment effect of the water to be treated, improving the utilization rate of carbon dioxide and reducing the recovery and treatment amount of surplus carbon dioxide.

[0060] Preferably, both the first flow regulating valve 7 and the second flow regulating valve 11 adopt automatic flow regulating valves with actuators, which are used to achieve: pipeline differences between the second branch pipes 5 and mixing effect differences of the gas-liquid mixers 9 on each second branch pipe 5 will result in different water treatment efficiencies (aeration efficiencies) of different second branch pipes 5. In this application, the control device can, according to the water treatment efficiencies of each second branch pipe 5, specifically control the water body flow rates in each second branch pipe 5 and the gas flow rates in each first branch pipe 3. By adjusting the water body flow rates and the mixing ratio of the water body flow rate and carbon dioxide, each second branch pipe 5 can complete the treatment of the water to be treated under efficient and economical working conditions. In specific applications, if, for reasons such as scaling, the efficiency of the second branch pipe 5 changes to a certain extent at different times, those skilled in the art can dynamically adjust the flow rate / mixing ratio based on the monitoring results of the pH value of the treated water body.

[0061] Embodiment 3:

[0062] This embodiment is further refined on the basis of Embodiment 1:

[0063] An axial flow pump 6 is provided on each second branch pipe 5, and the axial flow pump 6 is located upstream of the gas-liquid mixer 9.

[0064] In the above solution, the axial flow pump 6 is used to enable the dissolution pressure environment of the gas in each second branch pipe 5 to be established separately. It can not only enable the internal pressure of each second branch pipe 5 to be independently controlled, but also, the above dissolution pressure environment is not affected by the head of the water inlet pump at the front end of the water inlet pipe 1, nor is it affected by the pressure loss caused by the pre-filter 13 on the water inlet pipe 1. In specific applications, this treatment device can be used as a complete set of equipment and flexibly applied to the water reuse systems of each mixing plant.

[0065] Embodiment 4:

[0066] This embodiment is further refined on the basis of Embodiment 1:

[0067] A reaction tank 14 is provided on each second branch pipe 5, and the reaction tank 14 is located between the gas-liquid mixer 9 and the back pressure valve 12.

[0068] In this solution, the reaction tank 14, as a pressure vessel connected to the second branch pipe 5, is used to temporarily store the water body mixed with carbon dioxide. Under the condition of shortening the pipeline length of the second branch pipe 5, it enables these water bodies to have sufficient pressure retention time so that the dissolved carbon dioxide can fully participate in the pH value adjustment.

[0069] Embodiment 5:

[0070] This embodiment is further refined on the basis of Embodiment 4:

[0071] The reaction tank 14 includes a pressure-bearing housing 17, an anti-corrosion lining layer 19 provided on the inner wall of the pressure-bearing housing 17, a porous support plate 20 provided inside the pressure-bearing housing 17 and located at the bottom side of the pressure-bearing housing 17, a stuffing box 18 supported on the porous support plate 20, and a water distributor 21 installed inside the pressure-bearing housing 17 and located below the porous support plate 20;

[0072] The pipeline between the gas-liquid mixer 9 and the reaction tank 14 is connected to the water distributor 21, and the connection position of the pipeline between the reaction tank 14 and the back pressure valve 12 on the reaction tank 14 is above the stuffing box 18.

[0073] This solution provides a specific structural form of the reaction tank 14, that is: the reaction tank 14 includes a pressure-bearing housing 17 as the main structure and the pressure-bearing boundary, and an anti-corrosion lining layer 19 as the protective layer of the pressure-bearing housing 17. The anti-corrosion lining layer 19 is preferably made of HDPE, PTFE board or other plastics that are acid and alkali resistant, have a smooth surface, and are not prone to calcium carbonate scaling. The porous support plate 20 can also be made of a plastic plate with sufficient strength. The porous support plate 20 is supported on the pressure-resistant housing through a 304 stainless steel support ring. The stuffing box 18 is used to evenly distribute the flow field in the pressure-bearing housing 17 and form a sedimentation area for calcium carbonate by-products. The water distributor 21 is used to evenly distribute the water inlet flow at each position on the bottom side of the porous support plate 20. When this treatment device is working, the fluid from the gas-liquid mixer 9 is evenly injected into the space below the porous support plate 20 through the water distributor 21, then passes upward through the porous support plate 20 and enters the stuffing box 18, and then further passes through the second branch pipe 5 and the back pressure valve 12 from the water outlet above the stuffing box 18, and is diverted to the water outlet pipeline 2. To facilitate the installation and maintenance of the water distributor 21 and the stuffing box 18, both the bottom and the top of the reaction tank 14 have heads that are detachable relative to the tank body. For the structural form of the reaction tank 14 provided above, the provided stuffing box 18 and water distributor 21 can evenly distribute the flow field in the reaction tank 14, so that the water body can have a stable residence time in the reaction tank 14 for the dissolved carbon dioxide to fully participate in the regulation of the water body pH value. At the same time, the reaction tank 14 itself has good anti-corrosion and anti-scaling capabilities. At the same time, the stuffing box 18 can be used for calcium carbonate sedimentation, so that the by-products are concentrated and retained in the reaction tank 14, reducing their impact on the valve core of the downstream back pressure valve 12 (the main impact is that when the upstream pressure of the back pressure valve 12 is insufficient and the valve core of the back pressure valve 12 closes, calcium carbonate becomes the abrasive between the valve core and the valve seat, resulting in rapid wear of the mating surface between the valve core and the valve seat).

[0074] Example 6:

[0075] This embodiment is further refined on the basis of Embodiment 5:

[0076] In the reaction tank 14, the pipeline between the reaction tank 14 and the back pressure valve 12 has a gas storage space 22 above the connection position on the reaction tank 14;

[0077] It also includes a detection device for detecting the pressure difference of the fluid at the inlet and outlet of the reaction tank 14.

[0078] The above solution aims to define the position of the fluid outlet on the reaction tank 14 relative to the top of the reaction tank 14, that is, the connection position of the pipeline between the reaction tank 14 and the back pressure valve 12 on the reaction tank 14 is below the top of the inner space of the reaction tank 14, and there is a gas storage space 22 above the outlet pipeline interface at this position. This solution aims to achieve: when the pressure fluctuates on the inlet side of the reaction tank 14, the gas stored in the gas storage space 22 can be used to expand or compress to stabilize the air pressure of the reaction tank 14. While stabilizing the pH value adjustment ability, it can avoid the valve core of the back pressure valve 12 being damaged due to frequent actions and being accelerated under the influence of calcium carbonate. The above detection device is used to indicate the pressure loss when the fluid flows through the reaction tank 14, that is, the detection result of the detection device can be used to indicate whether maintenance is required for the stuffing box 18 and the stainless steel middle drain as the water distributor 21.

[0079] In a specific embodiment, the gas stored in the gas storage space 22 is used as a buffer gas to maintain pressure stability. For example, nitrogen that is difficult to dissolve in water under pressure is used, and this buffer gas can be injected into the reaction tank 14 through an exhaust pipe 23 connected to the reaction tank 14.

[0080] Embodiment 7:

[0081] This embodiment is further refined on the basis of Embodiment 6:

[0082] It also includes a gas sensor 15 and a safety valve 16 installed on the top of the reaction tank 14. The gas sensor 15 is used to detect the composition of the gas in the gas storage space 22.

[0083] In this solution, the safety valve 16 is used as a safety accessory on the top of the reaction tank 14 to avoid overpressure inside the reaction tank 14; the gas sensor 15 is used to obtain the gas in the gas storage space 22 sufficiently. For example, by detecting the content of carbon dioxide in the gas phase of the gas storage space 22, it can be determined whether the carbon dioxide introduced through the first branch pipe 3 is excessive, so as to avoid situations where, when the carbon dioxide is excessive, not only is it necessary to maintain the liquid level in the reaction tank 14 through exhaust, but also it is necessary to evacuate or further absorb the discharged carbon dioxide, increasing the environmental burden and water treatment cost.

[0084] Embodiment 8:

[0085] This embodiment is further refined on the basis of Embodiment 6:

[0086] It also includes an exhaust pipe 23 and a safety valve 16 installed at the top of the reaction tank 14. The exhaust pipe 23 is used to discharge the gas in the gas storage space 22.

[0087] In this solution, the safety valve 16 serves as a safety accessory at the top of the reaction tank 14 to avoid overpressure inside the reaction tank 14. The exhaust pipe 23 is used to discharge the gas at the top of the reaction tank 14 when there is an excess of carbon dioxide, so as to maintain the liquid level in the reaction tank 14 and improve the utilization rate of the internal space of the reaction tank 14. In specific applications, the exhaust pipe 23 is a Y-shaped pipe. Among the three pipe openings of the exhaust pipe 23, one pipe opening is connected to the reaction tank 14. Among the other two pipe openings, one pipe opening serves as the exhaust port for the reaction tank 14 to exhaust to the outside, and the other pipe opening serves as the injection port for injecting nitrogen into the pipe of the reaction tank 14 through the exhaust pipe 23. As a person skilled in the art, at least two control valves should be connected to the exhaust pipe 23, respectively used to control the conduction state between the reaction tank 14 and different pipe openings.

[0088] Example 9:

[0089] This embodiment is further refined on the basis of Embodiment 1:

[0090] The gas-liquid mixer 9 includes a jet mixer and a static mixer. The static mixer is arranged on the outlet side of the jet mixer. The connection position of the first branch pipe 3 on the gas-liquid mixer 9 is located on the jet mixer.

[0091] The static mixer is provided with spoiler plates that cause the fluid to form a turbulent flow pattern.

[0092] It also includes a control device for controlling the water flow rate in each second branch pipe 5 and the gas flow rate in each first branch pipe 3.

[0093] The above solution provides a specific implementation form of the gas-liquid mixer 9. The jet mixer is a mixer that sucks in carbon dioxide based on the negative pressure formed by the water flow (which can be assisted by the carbon dioxide gas source pressure to ensure the carbon dioxide injection volume) and realizes the mixing of carbon dioxide and water. The mixing effect of this mixer is affected by the water flow rate in the mixer. Since there is a back pressure valve 12 at its subsequent stage and according to the treatment requirements, the water flow rate at its previous stage may be unstable. When the flow rate is small, there are problems such as poor mixing efficiency and affecting the carbon dioxide dissolution rate. Based on this, it is further set to also include a static mixer. In the process of the gas-liquid mixer 9, the preliminary mixing of gas and liquid is first completed by the jet mixer, and then it enters the static mixer to complete further mixing. While reducing the pressure loss, the dissolution rate of carbon dioxide can be effectively guaranteed. The above control device is used to control the flow ratio of the water to be treated and carbon dioxide, so as to achieve the purpose of ensuring the control accuracy of the carbon dioxide injection volume.

[0094] Example 10:

[0095] Based on Embodiment 1, this embodiment provides a pipeline-type reclaimed water treatment method, which adjusts the pH value of the water to be treated by carbon dioxide, and this method is implemented based on the treatment device described in Embodiment 1;

[0096] In this method, the water to be treated from the inlet pipeline 1 is distributed to each second branch pipe 5, and carbon dioxide from the inlet gas pipeline 4 is introduced into the gas-liquid mixer 9 through the first branch pipe 3 to achieve the gas-liquid mixing of the water to be treated and carbon dioxide. Among them, the water flow rate of any second branch pipe 5 and the carbon dioxide flow rate introduced into this second branch pipe 5 have a set ratio. During the pH value adjustment process, the internal pressure of the corresponding second branch pipe 5 is established and maintained through each back pressure valve 12. This treatment method is the treatment method for adjusting the pH value of the water to be treated when the above treatment system is applied.

[0097] The above content is a further detailed description of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific embodiments of the present invention are only limited to these descriptions. For those of ordinary skill in the technical field to which the present invention belongs, other embodiments obtained without departing from the technical solution of the present invention should all be included within the protection scope of the present invention.

Claims

1. A pipeline-type grey water treatment device, comprising a water inlet pipeline (1), an air inlet pipeline (4) and a water outlet pipeline (2), characterized in that: A plurality of second branch pipes (5) are connected between the water inlet pipe (1) and the water outlet pipe (2), the number of the second branch pipes (5) is greater than or equal to 2, and the second branch pipes (5) are connected in parallel with each other; Each second branch pipe (5) is provided with a gas-liquid mixer (9) and a back pressure valve (12). In the flow of the second branch pipe (5), the gas-liquid mixer (9) is located upstream of the back pressure valve (12); It also includes first branch pipes (3) whose number is equal to the number of second branch pipes (5), and the gas-liquid mixers (9) on each second branch pipe (5) are connected to the air intake pipeline (4) through a separate first branch pipe (3).

2. The pipeline type reclaimed water treatment device according to claim 1, characterized in that: Each second branch pipe (5) is provided with a first flow regulating valve (7) and a first flow meter (8), wherein the first flow regulating valve (7) is used to adjust the water flow on the second branch pipe (5), and the first flow meter (8) is used to detect the water flow on the second branch pipe (5); Each first branch pipe (3) is provided with a second flow meter (10) and a second flow regulating valve (11); the second flow meter (10) is used to detect the gas flow on the first branch pipe (3); and the second flow regulating valve (11) is used to adjust the gas flow on the first branch pipe (3).

3. The pipeline type reclaimed water treatment device according to claim 1, characterized in that: Each second branch pipe (5) is provided with an axial flow pump (6), and the axial flow pump (6) is located upstream of the gas-liquid mixer (9).

4. The pipeline type reclaimed water treatment device according to claim 1, characterized in that: A reaction tank (14) is provided on each second branch pipe (5), and the reaction tank (14) is located between the gas-liquid mixer (9) and the back pressure valve (12).

5. The pipeline type reclaimed water treatment device according to claim 4, characterized in that: The reaction tank (14) comprises a pressure-bearing shell (17), an anti-corrosion lining layer (19) arranged on the inner wall of the pressure-bearing shell (17), a porous support plate (20) arranged inside the pressure-bearing shell (17) and located at the bottom side of the pressure-bearing shell (17), a stuffing box (18) supported on the porous support plate (20), and a water distributor (21) installed inside the pressure-bearing shell (17) and located below the porous support plate (20); The pipeline between the gas-liquid mixer (9) and the reaction tank (14) is connected to the water distributor (21), and the connection position of the pipeline between the reaction tank (14) and the back pressure valve (12) on the reaction tank (14) is located above the stuffing box (18).

6. The pipeline type reclaimed water treatment device according to claim 5, characterized in that: In the reaction tank (14), the pipeline between the reaction tank (14) and the back pressure valve (12) has a gas storage space (22) above the connection position on the reaction tank (14); It also includes a detection device for detecting the pressure difference between the inlet and outlet fluids of the reaction tank (14).

7. The pipeline type reclaimed water treatment device according to claim 6, characterized in that: It also includes a gas sensor (15) and a safety valve (16) installed on the top of the reaction tank (14), wherein the gas sensor (15) is used to detect the composition of the gas in the gas storage space (22).

8. The pipeline type reclaimed water treatment device and treatment method according to claim 6, characterized in that: It also includes an exhaust pipe (23) and a safety valve (16) installed on the top of the reaction tank (14), wherein the exhaust pipe (23) is used to discharge the gas in the gas storage space (22).

9. The pipeline type reclaimed water treatment device according to claim 1, characterized in that: The gas-liquid mixer (9) comprises a jet mixer and a static mixer, wherein the static mixer is arranged at the outlet side of the jet mixer, and the connection position of the first branch pipe (3) on the gas-liquid mixer (9) is located on the jet mixer; It also includes a control device for controlling the water flow in each second branch pipe (5) and the gas flow in each first branch pipe (3).

10. A pipeline water treatment method, wherein the pH value of the water to be treated is adjusted by using carbon dioxide, characterized in that: The method is implemented based on the processing device described in any one of claims 1 to 9; In the method, the water to be treated from the water inlet pipeline (1) is distributed to each second branch pipe (5), and the carbon dioxide from the air inlet pipeline (4) is introduced into the gas-liquid mixer (9) through the first branch pipe (3) to achieve gas-liquid mixing of the water to be treated and the carbon dioxide, wherein the water flow rate of any second branch pipe (5) and the carbon dioxide flow rate introduced into the second branch pipe (5) have a set ratio, and during the pH value adjustment process, the internal pressure of the corresponding second branch pipe (5) is established and maintained through each back pressure valve (12).

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