Method for treating secondary pollution of direct drinking water pipeline and direct drinking water pipeline system

Abstract

The application discloses a pipeline direct drinking water secondary pollution treatment method and a pipeline direct drinking water system. The treatment method comprises the following steps: setting a first working mode and a second working mode according to the water use frequency of users in a target area; in the first working mode, a circulating driving device is started for a first preset time length every first preset period, and a circulating treatment device performs ozone sterilization for a second preset time length and ultraviolet sterilization for a third preset time length every first preset period; and in the second working mode, the circulating driving device is closed. The treatment method solves the problems of excessive microorganisms in water caused by pipeline secondary pollution, excessive bromate caused by excessive ozone, and high cost caused by the continuous opening of the circulating driving device at a low cost by controlling the ozone sterilization time length, the ultraviolet sterilization time length, and the water circulation time length of the circulating driving device in the first working mode.

Description

Technical Field

[0001] The present invention relates to the technical field of piped drinking water, and in particular to a method for treating secondary pollution of piped drinking water and a piped drinking water system. Background Art

[0002] Direct drinking water systems will be established in office buildings, teaching buildings, dormitories and other places for the convenience of users. The direct drinking water system mainly purifies the raw water by sterilizing and disinfecting it with purification equipment in the main machine room to produce direct drinking water. The direct drinking water is stored in water tanks, and water dispensers are installed in various dormitories, classrooms and other locations. The water tanks are supplied to each water dispenser through water supply pipes.

[0003] In the existing technology, due to the long distance between the water tank and each water dispenser, in order to ensure the hygienic safety of drinking water reaching the end of the water supply pipeline and avoid sensory discomfort and potential risks to user health caused by microbial regeneration, it is necessary to disinfect the drinking water. First, pathogenic microorganisms in the source water are killed or inactivated; second, by retaining a certain amount of disinfectant, microorganisms are prevented from re-growth and the biological stability of the drinking water is ensured. Among the many drinking water disinfection methods, ozone is highly favored due to its strong ability to inactivate a variety of microorganisms and its lack of chlorine odor. In recent years, its scope of application in actual projects has gradually expanded. However, ozone is unstable and easily decomposed, resulting in poor continuous disinfection effect. In addition, ozone can oxidize large organic molecules in water into small organic molecules that are easily biodegradable, thereby providing nutrients for microorganisms, causing microorganisms in the pipeline to grow and reproduce again, affecting water quality and threatening user health. In addition, the scale of the piped drinking water system matches the water consumption of users in the target environment, but the frequency of water use by users in different application environments is different. If drinking water is not used for a long time or the amount used is small, the drinking water in the water supply pipe will accumulate for a long time and easily cause secondary pollution, resulting in the water quality at the time of water collection being completely unable to meet drinking standards.

[0004] Prior art also uses ultraviolet disinfection to disinfect drinking water, but during peak water usage, it's difficult to match ultraviolet disinfection with water volume, resulting in extremely limited disinfection effectiveness and the resulting drinking water failing to meet drinking water standards. Consequently, prior art also uses a combination of ozone and ultraviolet disinfection. However, in practice, due to the frequency of water use in different environments, there are also issues with excessive ozone concentrations, resulting in excessive levels of bromate as a byproduct, and prolonged ultraviolet exposure, resulting in water quality failing to meet drinking water standards.

[0005] Although some piped drinking water systems are equipped with circulation systems to keep the water circulating and purified, the energy consumption and cost of keeping the water circulation on are high, and the circulation drive device is usually turned on intermittently or periodically. Therefore, it will still be affected by ozone concentration, water accumulation in the pipes, and the duration of ultraviolet disinfection. Summary of the Invention

[0006] The present invention provides a method for treating secondary pollution of piped drinking water and a piped drinking water system, so as to solve the technical problem in the prior art that piped drinking water is easily polluted when accumulated in a pipe.

[0007] The technical solution adopted in the present invention is as follows:

[0008] A method for treating secondary contamination of piped drinking water is provided, which is used in a piped drinking water system. The piped drinking water system includes a water production system, a circulating water supply system, and a control system. The circulating water supply system includes a circulating drive device, a circulating treatment device, a water storage device connected to the water production system, and a water intake device provided at each target water supply location. The water intake device is connected to the water storage device via a water supply pipe. The circulating drive device is used to extract water from the water supply pipe through the circulating pipe to the circulating treatment device for purification treatment. The treatment method includes:

[0009] The first and second working modes are set according to the water usage frequency of users in the target area.

[0010] In the first working mode, the circulation drive device starts the first preset duration every first preset cycle, and the circulation treatment device performs ozone disinfection for a second preset duration and ultraviolet disinfection for a third preset duration every first preset cycle, and the starting point of the first preset duration is the same as the starting point of the first preset cycle; the starting point of the second preset duration is the same as the starting point of the first preset cycle, and / or the starting point of the third preset duration is the same as the starting point of the first preset cycle; the second preset duration and the third preset duration overlap or are alternately distributed or spaced within the first preset cycle;

[0011] In the second operating mode, the circulation drive is turned off.

[0012] As a further improvement of the above technical solution, the second preset time length and the third preset time length are set in a preset ratio.

[0013] As a further improvement of the above technical solution, the first preset period is 0.5-3 hours, the second preset duration is 0.01-0.6 hours, and the third preset duration is 0.1-0.6 hours.

[0014] As a further improvement of the above technical solution, when the first working mode and the second working mode are set respectively according to the water usage frequency of users in the target area, the processing method also includes: when the water usage rate is lower than the preset value for more than a fourth preset time, the first working mode is turned on; when the water usage rate is higher than the preset value, the second working mode is turned on.

[0015] As a further improvement of the above technical solution, the piped drinking water system is provided with a dosing device connected to the water storage device, and the treatment method includes:

[0016] At intervals of every second preset period, the control system controls the dosing device to add a preset amount of disinfectant to the water storage device, and the control system controls the circulation drive device to operate so that the water in the pipe direct drinking water system circulates in the pipe direct drinking water system for a preset time.

[0017] As a further improvement of the above technical solution, the control system controls the circulation drive device to make the water in the piped direct drinking water system circulate in the piped direct drinking water system for a preset time, and the treatment method also includes: opening the water intake device to release the water in the piped direct drinking water system.

[0018] As a further improvement of the above technical solution, the processing method also includes: first preset time length*circulation drive device flow rate≥water storage capacity of water supply pipeline.

[0019] As a further improvement of the above technical solution, the water storage capacity of the water storage device matches the water consumption of the target area, with a water storage device with a water storage capacity of 500-700L matching every 500 people, and a water storage device with a water storage capacity of 900-1100L matching every 1000 people.

[0020] As a further improvement of the above technical solution, the power of the ultraviolet disinfection matched with the 500-700L water storage device is 20W, and the power of the ultraviolet disinfection matched with the 900-1100L water storage device is 40W; the concentration of the ozone disinfection matched with the 500-700L water storage device is 0.5g / h; the concentration of the ozone disinfection matched with the 900-1100L water storage device is 1g / h.

[0021] According to another aspect of the present invention, a piped drinking water system is provided, to which any of the above-mentioned methods for treating secondary pollution of piped drinking water is applied.

[0022] The present invention has the following beneficial effects: the treatment method sets a first working mode and a second working mode according to the water use frequency of users in the target area. The first working mode is used when the water use frequency is low or no water is used. The circulation drive device works for a first preset time in each first preset cycle. The circulation treatment device performs ozone disinfection for a second preset time in each first preset cycle and performs ultraviolet disinfection for a third preset time in each first preset cycle. Moreover, the starting point of the first preset time is the same as the starting point of the first preset cycle, that is, when the first working mode is turned on, the circulation drive device is started to make the water stored in the water supply pipe flow back to the water storage device for disinfection. The starting point of the second preset time period or the third preset time period is the same as the starting point of the first preset period, that is, the first preset period is calculated when entering the first working mode and at least one disinfection method is enabled at the same time to avoid the increase in system water consumption and the failure to effectively perform disinfection after switching to the second working mode; the first preset period is a period set comprehensively based on the changes in water quality in the pipeline under different application environments and the water use rate under the application environment, that is, the first preset period should be less than the time when the quality of direct drinking water in the system does not meet the requirements due to secondary contamination of the pipeline, and the first preset period is set within this time range with reference to the water use habits of users in the application environment; the second preset period is the same as the third preset period. The three preset time lengths can overlap or be distributed alternately or at intervals, that is, ozone disinfection and ultraviolet disinfection can be turned on simultaneously or alternately or at intervals; by controlling the ozone disinfection time length, ultraviolet disinfection time length and the time length of the circulation drive device driving the water circulation in the first working mode, the water in the pipeline is circulated to ensure that the microorganisms in the water output by the water intake device are lower than the warning value and the ozone by-product bromate is lower than the warning value, thereby avoiding secondary pollution of the pipeline. By reasonably allocating the time lengths of ozone disinfection and ultraviolet disinfection, the advantage of ultraviolet disinfection without by-products is fully utilized under low water consumption conditions, and the problem of ozone accumulation and decomposition to produce oxides that cause microorganisms to breed again is avoided. The second working mode is activated when the water use frequency is higher than the preset value, and the circulation treatment device is closed. At this time, the direct drinking water in the pipeline stays for a very short time. According to the pipeline secondary pollution treatment method, the pipeline direct drinking water system is matched with the water consumption and water use habits in the application environment. The working modes are differentiated according to low-peak water use and peak water use. The circulation treatment and disinfection treatment are selectively started. The problems of excessive microorganisms in water caused by secondary pollution of pipelines, excessive bromate caused by excessive ozone, difficulty in matching water consumption with ultraviolet disinfection, and high cost caused by keeping the circulation drive device turned on are solved under the condition of relatively low cost.

[0023] In addition to the above-described objects, features and advantages, the present invention has other objects, features and advantages. The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0025] Figure 1 It is a simplified structural diagram of a preferred embodiment of the present invention;

[0026] Figure 2 It is a structural diagram of embodiment 1 of the present invention;

[0027] 9. Water supply pipeline 10. Water intake device 11. Circulation pipeline 100. Water production system. DETAILED DESCRIPTION

[0028] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0029] Reference Figures 1 to 2 A preferred embodiment of the present invention provides a method for treating secondary pollution of piped drinking water, which is used in a piped drinking water system. The piped drinking water system includes: a water production system 100, which is used to connect to an external water source and purify the input water to output drinking water; a circulating water supply system, including a water storage device for storing drinking water purified by the water production system 100, and the water storage device is connected to the water production system 100; it also includes a water intake device 10 respectively arranged at each target water supply position, and the water intake device 10 is connected to the water storage device through a water supply pipe 9; it also includes a circulation drive device and a circulation treatment device, an inlet end of the water storage device is connected to an end of the water supply pipe 9 close to the water intake device 10 or an end connected to the water outlet of the water intake device 10 through a circulation pipe 11, and the circulation treatment device is arranged in the water storage device or on the circulation pipe 11; the circulation drive device is used to extract water in the water supply pipe 9 through the circulation pipe 11 to the circulation treatment device for purification.

[0030] It should be understood that the water intake device 10 can be a water dispenser, faucet, etc. arranged at each target water supply location; the water dispenser uses a 3G-certified wall-mounted water dispenser, and the water dispenser has a certain water storage capacity, which can effectively alleviate the water supply pressure in large-scale water use and ensure the water output; the circulation drive device is a food-grade circulation pump arranged on the water supply pipe 9 and / or the circulation pipe 11, specifically a food-grade 304 stainless steel circulation pump CWP; each pipe (i.e., the water supply pipe 9, the circulation pipe 11) uses a food-grade PPR pipe or a food-grade PE pipe; the water storage device includes a food-grade water tank.

[0031] It can be understood that this piped direct drinking water system purifies the external water source through the water production system 100 and then stores it in the water storage device. The water storage device supplies water to each water intake device 10 through the water supply pipe 9 of the circulating water supply system. The user can take direct drinking water from the water intake device 10 at any target water intake position; the circulating pipe 11 connects the water outlet end position near the water intake device 10 to the water production system 100, and the circulation driving device drives the water in the water supply pipe 9 through the circulating pipe 11 to the circulation treatment device, and the circulation treatment device purifies the water again and then sends it to the water storage device. The circulation treatment of the water in the pipe and the water dispenser effectively solves the secondary pollution problem of direct drinking water in the water supply pipe 9 and ensures water quality.

[0032] It should be noted that the direct drinking water system can be further provided with a control system for controlling the opening and closing time of the recycling and processing device and the circulation drive device, thereby controlling the interval and single processing time of the water circulation treatment in the pipeline; its specific setting time should be adaptively set according to the amount of water that can be stored in the pipeline under the system scale, and can be further adaptively set according to the water extraction time distribution under the system setting environment; in this embodiment, the water production system 100 includes a filtering device, and the filtering device includes a reverse osmosis water purifier and / or a nanofiltration water purifier, which is selectively set according to actual conditions, wherein, in the nanofiltration water purifier, the pore size range of the nanofiltration element is between 0.01-0.001 microns; it can filter out chemical pollutants such as antibiotics, hormones, pesticides, petroleum, detergents, heavy metals, algae toxins, etc.; while mineral ions smaller than this pore size can pass through; it can effectively retain beneficial minerals; the reverse osmosis water purifier uses a special high-pressure water pump to increase the raw water pressure, so that the raw water permeates through the reverse osmosis membrane with a pore size of only 0.0001 microns under the action of pressure. Chemical ions, bacteria, fungi and viruses cannot pass through and are discharged with the wastewater. Only pure water molecules with a volume of less than 0.0001 microns are allowed to pass through, that is, pure water. The circulating treatment device includes an ozone treatment device, and the ozone treatment device includes an ozone generator and a mixer 6. The mixer 6 is used to mix the input water with ozone for purification.

[0033] The circulating treatment unit also includes ultraviolet disinfection lamps. Ultraviolet disinfection utilizes ultraviolet light of appropriate wavelengths to destroy the molecular structure of DNA (deoxyribonucleic acid) or RNA (ribonucleic acid) in microbial cells, causing cell death in the growth and / or regeneration stages, achieving a sterilization effect. Ultraviolet disinfection technology is based on modern epidemiology and photodynamics. It utilizes specially designed, high-efficiency, high-intensity, and long-life UVC-band ultraviolet light to irradiate flowing water, directly killing various bacteria, viruses, parasites, algae, and other pathogens in the water.

[0034] In this embodiment, the circulation drive device includes a water collector, the outlet end of the water collector is connected to the water storage device through a circulation pipe 11, and the water outlet end of each water intake device 10 is connected to the inlet end of the water collector through the circulation pipe 11.

[0035] It can be understood that the water production system 100, control system, water storage device, circulation treatment device and circulation drive device of this embodiment can be arranged in the same control room / machine room, which is convenient for operation and maintenance.

[0036] This treatment method includes:

[0037] The first and second working modes are set according to the water usage frequency of users in the target area.

[0038] In the first working mode, the circulation drive device starts the first preset duration every first preset cycle, and the circulation treatment device performs ozone disinfection for a second preset duration and ultraviolet disinfection for a third preset duration every first preset cycle. The starting point of the first preset duration is the same as the starting point of the first preset cycle; the starting point of the second preset duration is the same as the starting point of the first preset cycle, and / or the starting point of the third preset duration is the same as the starting point of the first preset cycle, and the second preset duration and the third preset duration overlap or are alternately distributed or spaced within the first preset cycle;

[0039] In the second operating mode, the circulation drive is turned off.

[0040] Among them, the water storage capacity of the water storage device matches the water consumption of the target area, among which, a water storage device with a water storage capacity of 500-700L is matched for every 100 people, and a water storage device with a water storage capacity of 900-1100L is matched for every 1000 people; the power of the ultraviolet disinfection matched by the 500-700L water storage device is 20W, and the power of the ultraviolet disinfection matched by the 900-1100L water storage device is 40W; the concentration of the ozone disinfection matched by the 500-700L water storage device is 0.5g / h; the concentration of the ozone disinfection matched by the 900-1100L water storage device is 1g / h; the rated power of the ozone generator of this embodiment is 405W, and the rated ozone output is: 5g / h; the maximum flow rate of the circulation drive device is 5 cubic meters / h, and the rated power is 1500W;

[0041] Specifically in this embodiment, the water consumption of 500 people is matched with a 600L water storage device, and every 1000 people are matched with a 1000L water storage device; the 600L water storage device uses a 20W power specification ultraviolet disinfection device, and the 1000L water storage device uses a 40W power specification ultraviolet disinfection device;

[0042] The first preset duration of this embodiment may be the total duration of disinfection within the first preset cycle, that is, the circulation drive device is kept turned on during the disinfection process; further, before performing any disinfection method, the circulation drive device is turned on for the first preset duration to ensure that the water stored in the water supply pipe flows into the water storage device, thereby achieving re-disinfection of the water stored in the original water supply pipe. Based on this, the first preset duration * the flow rate of the circulation drive device ≥ the water storage volume of the water supply pipe;

[0043] It can be understood that the present treatment method sets the first working mode and the second working mode respectively according to the water use frequency of users in the target area. The first working mode is used when the water use frequency is low or no water is used. The circulation drive device works for the first preset time in each first preset cycle. The circulation treatment device performs ozone disinfection for the second preset time in each first preset cycle and performs ultraviolet disinfection for the third preset time in each first preset cycle. Moreover, the starting point of the first preset time is the same as the starting point of the first preset cycle. That is, when the first working mode is turned on, the circulation drive device is started to make the water in the water supply pipe flow back to the water storage device for disinfection; the second preset time The starting point of the longest time or the starting point of the third preset time is the same as the starting point of the first preset period, that is, the first preset period is calculated when entering the first working mode and at least one disinfection method is enabled at the same time to avoid the increase of system water consumption and the failure to effectively perform disinfection after switching to the second working mode; the first preset period is a period set comprehensively according to the changes in water quality in the pipeline under different application environments and the water use rate under the application environment, that is, the first preset period should be less than the time when the quality of direct drinking water in the system does not meet the requirements due to secondary contamination of the pipeline, and the first preset period is set within this time range with reference to the water use habits of users in the application environment; the second preset time is the same as the third preset time. The durations can overlap or be distributed alternately or at intervals, that is, ozone disinfection and ultraviolet disinfection can be turned on simultaneously or alternately or at intervals; by controlling the duration of ozone disinfection in the first working mode, the duration of ultraviolet disinfection, and the duration of water circulation driven by the circulation drive device, the water in the pipeline is circulated to ensure that the microorganisms in the water output by the water intake device are lower than the warning value, and the ozone by-product bromate is lower than the warning value, thereby avoiding secondary pollution of the pipeline. By reasonably allocating the durations of ozone disinfection and ultraviolet disinfection, the advantage of ultraviolet disinfection without by-products is fully utilized under low water consumption conditions, and the problem of ozone accumulation and decomposition to produce oxides that cause microorganisms to breed again is avoided. At the same time, the cost of disinfection treatment is greatly reduced; when the water use frequency is higher than the preset value, the second working mode is turned on and the circulation treatment device is turned off. At this time, the direct drinking water in the pipeline stays for a very short time; according to the pipeline secondary pollution treatment method, the pipeline direct drinking water system is matched with the water consumption and water use habits in the application environment, and the working mode is differentiated according to low-peak water use and peak water use, and the circulation treatment and disinfection treatment are selectively turned on, which solves the problems of excessive microorganisms in water caused by secondary pollution of the pipeline, excessive bromate caused by excessive ozone, the difficulty of matching water consumption with ultraviolet disinfection, and the high cost problem caused by keeping the circulation drive device turned on under the condition of relatively low cost.

[0044] Among them, when the first working mode and the second working mode are set respectively according to the water use frequency of users in the target area, the processing method specifically includes: when the water use rate is lower than the preset value and exceeds the fourth preset time, the first working mode is turned on, and when the water use rate is higher than the preset value, the second working mode is turned on; the fourth preset time is set according to the water quality changes in different application environments. Based on this, the fourth preset time is approximately the first preset period. In this embodiment, taking 2 hours as an example, within the fourth preset time, it can be ensured that the water quality meets the requirements. If the water use rate is higher than the preset value, the water in the water supply pipe is basically discharged; if the water use rate is lower than the preset value or no water is used for more than the fourth preset time, the water in the pipe will be stored for a long time and the water quality will be reduced to a level that does not meet the requirements of direct drinking water. The first working mode is turned on for circulation treatment and disinfection to ensure water quality; further, the fourth preset time can also be calculated according to the real-time change of the water use rate, that is, the time when the water in the pipe is stored is calculated according to the water storage capacity, water use rate and time of the water supply pipe in the application environment, to ensure that the accumulation time of water in the pipe does not exceed the fourth preset time;

[0045] The second preset time length and the third preset time length of this embodiment are set in a preset ratio. For example, in this embodiment, the second preset time length and the third preset time length are preferably set to 1:0.5-1:2. Under this ratio range, the water quality of the two disinfection methods working in combination is better; and ozone disinfection and ultraviolet disinfection are preferably turned on at intervals, and ultraviolet disinfection is performed after ozone disinfection. Then the first preset time length is the sum of the second preset time length and the third preset time length. Under this ratio setting condition and the interval opening condition, the disinfection capacity of the two disinfection methods is fully utilized, while ensuring that the microorganisms and disinfection by-products in the water do not exceed the standard; in some embodiments, ozone and ultraviolet can also be turned on at the same time, or part of the opening time overlaps. In this case, the first preset time length is the sum of the second preset time length to the second preset time length and the third preset time length;

[0046] Specifically, the first preset period of this embodiment is 0.5-3h, the second preset duration is 0.01-0.6h, and the third preset duration is 0.1-0.6h. It can be understood that the second preset duration increases with the increase of the period duration of the first preset period, and the third preset duration increases with the increase of the period duration of the first preset period.

[0047] In this embodiment, the piped drinking water system is further provided with a dosing device connected to the water storage device. Based on this, the treatment method includes:

[0048] At intervals of every second preset period, the control system controls the dosing device to add a preset amount of disinfectant to the water storage device, and the control system controls the circulation drive device to operate so that the water in the pipe direct drinking water system circulates in the pipe direct drinking water system for a preset time; specifically, the second preset period can be half a year, a quarter, or a month. In this embodiment, it is applied to a campus environment and takes half a year as an example. Within one week before the start of school, the water supply pipe and the circulation pipe are cleaned. During cleaning, all water intake devices are closed and stopped. The dosing device adds a preset amount of disinfectant to the water storage device (for example, 10 effervescent tablets per 100L) to form a disinfectant solution, and the circulation drive device operates to circulate the disinfectant in the pipe to achieve pipe cleaning. The circulation drive device is turned off after circulating for 2 hours, and the disinfectant solution is allowed to soak in the pipe for more than 24 hours;

[0049] After the control system controls the circulation drive device to operate so that the water in the pipe direct drinking water system circulates in the pipe direct drinking water system for a preset time, the processing method further includes:

[0050] Open the water intake device and release the water in the piped drinking water system; that is, after soaking for more than 24 hours, open the water outlet of the water intake device, release all the disinfectant in the water intake device and the disinfectant in the pipeline, and then close it, that is, the amount of water released should be greater than the water storage capacity of the water storage device; start water production, open the water outlet of the water intake device to output water for a preset time until clean water flows out, close the water outlet of the water intake device, and complete the cleaning.

[0051] It should be understood that the present treatment method is applied to the aforementioned piped drinking water system, and is implemented by the control system of the piped drinking water system controlling the circulation drive device and the circulation treatment device respectively.

[0052] Example 1

[0053] like Figure 2 As shown, the small-scale piped direct drinking water system of this embodiment is applied to a teaching building. The water production system 100, control system, water storage device, circulation treatment device and circulation drive device are all arranged in the machine room on the top floor. A wall-mounted water dispenser is set next to the door of each classroom. The water production system 100 is connected to each water dispenser by a water supply pipe 9, and the circulation pipe 11 is connected to the water production system 100 and is connected to the water supply pipe 9 near each water dispenser.

[0054] The campus environment of this embodiment takes the total number of teachers and students in the target teaching building as an example of 500, and the capacity of the water storage device used is 600L; the power of ultraviolet disinfection is 20W, and the working power of the ozone generator is set to 15W, that is, the concentration of ozone disinfection is 0.5g / h; it should be understood that the above parameter setting conditions can disinfect the water quality under normal use; the first preset cycle is 2h, the first preset time is 1h, the second preset time is 0.5h, and the third preset time is 0.5h; the water sample test results of this embodiment are: chlorate <0.050, bromate <0.005, chlorite <0.050, microbial content 0, Escherichia coli test negative, and the water quality meets the requirements.

[0055] Comparative Example 1

[0056] In this comparative example, a piped drinking water system in the prior art was used, ozone disinfection was turned off, and ultraviolet disinfection was turned on for 10 hours. The water sample test results were: chlorate 0.239, bromate <0.005, and chlorite <0.050.

[0057] Comparative Example 2

[0058] In this comparative example, a piped drinking water system in the prior art was used, ozone disinfection was turned off, and ultraviolet disinfection was turned on for 24 hours. The water sample test results showed: chlorate 0.254, bromate <0.005, and chlorite <0.050.

[0059] Comparative Example 3

[0060] In this embodiment, a piped drinking water system in the prior art was used, with UV disinfection turned off and ozone disinfection turned on for 10 hours. The water sample test results showed that chlorate was less than 0.050, bromate was less than 0.005, and chlorite was less than 0.050.

[0061] Comparative Example 4

[0062] In this embodiment, a piped drinking water system in the prior art was used, with UV disinfection turned off and ozone disinfection turned on for 24 hours. The water sample test results showed that chlorate was less than 0.050, bromate was less than 0.005, and chlorite was less than 0.050.

[0063] Comparative Example 5

[0064] In this embodiment, a piped drinking water system in the prior art was used, and ultraviolet disinfection and ozone disinfection were simultaneously turned on for 10 hours. The water sample test results showed that chlorate was 0.057, bromate was less than 0.005, and chlorite was less than 0.050.

[0065] Comparative Example 6

[0066] In this embodiment, a piped drinking water system in the prior art was used, and ultraviolet disinfection and ozone disinfection were simultaneously turned on for 24 hours. The water sample test results showed that chlorate was less than 0.050, bromate was less than 0.005, and chlorite was less than 0.050.

[0067] Comparative Example 7

[0068] In this embodiment, a piped drinking water system in the prior art was used, and UV disinfection and ozone disinfection were simultaneously turned on for 5 hours. The water sample test results showed: chlorate <0.050, bromate <0.005, chlorite <0.050, microbial content 151, and E. coli test negative;

[0069] In this embodiment, a piped drinking water system in the prior art was used, and ultraviolet disinfection and ozone disinfection were turned on simultaneously for 5 hours. The water sample test results were: chlorate <0.050, bromate <0.005, chlorite <0.050, microbial content 335, and E. coli test negative.

[0070] Comparative Example 8

[0071] In this embodiment, a piped drinking water system in the prior art was used, ultraviolet disinfection was turned off, and ozone disinfection was turned on for 5 hours. The water sample test results were: chlorate 0.272, bromate <0.005, chlorite <0.050, microbial content 8, and E. coli test negative.

[0072] Comparative Example 9

[0073] In this embodiment, a piped drinking water system in the prior art was used, ultraviolet disinfection was turned off, and ozone disinfection was turned on for 5 hours. The water sample test results were: chlorate 0.272, bromate <0.005, chlorite <0.050, microbial content 21, and E. coli test negative.

[0074] Comparative Example 10

[0075] In this example, a conventional piped drinking water system was used to disinfect water from a specific water production unit. After the initial disinfection, ozone disinfection was repeated five times for 99 seconds every hour. The water sample test results showed: chlorate <0.050, bromate <0.005, chlorite <0.050, microbial count <1, and negative E. coli.

[0076] Comparative Example 11

[0077] In this embodiment, a piped drinking water system in the prior art was used to disinfect the water in a certain water production host for the first time. Ozone disinfection was turned on for 99 seconds every hour, and ultraviolet disinfection was kept on, and repeated 5 times. The water sample test results were: chlorate 0.068, bromate <0.005, chlorite <0.050, microbial content 0, and E. coli test negative.

[0078] Comparative Example 12

[0079] In this embodiment, a piped drinking water system in the prior art was used to disinfect the water in a certain water production host for the first time. Ozone disinfection was then turned on for 99 seconds every hour and repeated 5 times. The water sample test results showed: chlorate <0.050, bromate <0.005, chlorite <0.050, microbial content 0, and negative E. coli test.

[0080] It is obvious from the above comparative examples that the use of the piped drinking water system in the prior art can basically ensure that the by-product bromate does not exceed the standard based on the proportional control of its ozone disinfection. However, ozone is easy to decompose and is unstable. The use time of only 5 hours will result in a high microbial content in the drinking water in the water tank. Although turning on ozone disinfection and ultraviolet disinfection for 5 hours at the same time reduces the microbial content to a certain extent, microbial growth still exists, that is, under long-term use, the water quality will inevitably fail to meet the standard. The direct drinking water system and treatment method according to the preferred embodiment of the present invention effectively suppress the problems of excessive microorganisms and excessive bromate in the water caused by secondary pollution of the pipeline and excessive ozone concentration by controlling the opening of ozone disinfection and ultraviolet disinfection, and at the same time avoid the difficulty of matching ultraviolet disinfection with large water consumption and the high cost problem caused by keeping the circulation drive device turned on, thereby ensuring the disinfection effect while reducing the system operation cost.

[0081] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A method for treating secondary pollution of piped drinking water, used in a piped drinking water system, characterized in that: The pipeline direct drinking water system includes a water production system, a circulating water supply system and a control system. The circulating water supply system includes a circulating drive device, a circulating treatment device, a water storage device connected to the water production system, and a water intake device arranged at each target water supply location. The water intake device is connected to the water storage device through a water supply pipeline. The circulating drive device is used to extract water in the water supply pipeline through the circulating pipeline to the circulating treatment device for purification. The treatment method includes: The first and second working modes are set according to the water usage frequency of users in the target area. In the first working mode, the circulation drive device starts the first preset duration every first preset cycle, and the circulation treatment device performs ozone disinfection for a second preset duration and ultraviolet disinfection for a third preset duration every first preset cycle, and the starting point of the first preset duration is the same as the starting point of the first preset cycle; the starting point of the second preset duration is the same as the starting point of the first preset cycle, and / or the starting point of the third preset duration is the same as the starting point of the first preset cycle; the second preset duration and the third preset duration overlap or are alternately distributed or spaced within the first preset cycle; In the second working mode, the circulation drive device is turned off; When the water usage rate is lower than the preset value for more than a fourth preset time period, the first working mode is turned on; when the water usage rate is higher than the preset value, the second working mode is turned on.

2. The method for treating secondary pollution of piped drinking water according to claim 1, characterized in that: The second preset time length and the third preset time length are set in a preset ratio.

3. The method for treating secondary pollution of piped drinking water according to claim 2, characterized in that: The first preset period is 0.5-3 hours, the second preset period is 0.01-0.6 hours, and the third preset period is 0.1-0.6 hours.

4. The method for treating secondary pollution of piped drinking water according to claim 1, characterized in that: The pipeline direct drinking water system is provided with a dosing device connected to the water storage device, and the treatment method includes: At intervals of every second preset period, the control system controls the dosing device to add a preset amount of disinfectant to the water storage device, and the control system controls the circulation drive device to operate so that the water in the pipe direct drinking water system circulates in the pipe direct drinking water system for a preset time.

5. The method for treating secondary pollution of piped drinking water according to claim 4, characterized in that: After the control system controls the circulation drive device to operate so that the water in the pipe direct drinking water system circulates in the pipe direct drinking water system for a preset time, the treatment method also includes: opening the water intake device to release the water in the pipe direct drinking water system.

6. The method for treating secondary pollution of piped drinking water according to claim 1, characterized in that: The processing method also includes: first preset time length*circulation drive device flow rate≥water storage capacity of water supply pipeline.

7. The method for treating secondary pollution of piped drinking water according to any one of claims 1 to 5, characterized in that: The water storage capacity of the water storage device matches the water consumption of the target area, with a water storage device with a water storage capacity of 500-700L matching every 500 people, and a water storage device with a water storage capacity of 900-1100L matching every 1000 people.

8. The method for treating secondary pollution of piped drinking water according to claim 7, characterized in that: The power of ultraviolet disinfection matched with the 500-700L water storage device is 20W, and the power of ultraviolet disinfection matched with the 900-1100L water storage device is 40W; the concentration of ozone disinfection matched with the 500-700L water storage device is 0.5g / h; the concentration of ozone disinfection matched with the 900-1100L water storage device is 1 g / h.

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