A water-saving reverse osmosis water purifier for wastewater reuse and surplus energy utilization

Abstract

A water-saving reverse osmosis water purifier that reuses wastewater for residual energy. The water source ball valve, water inlet solenoid valve, granular activated carbon filter, compressed activated carbon filter, fine fiber cotton filter, and booster pump are connected in series. The booster pump is connected in parallel with a low-pressure switch. The reverse osmosis unit inlet is connected to the booster pump outlet, and the purified water outlet is connected to a water tank equipped with a float water level switch and an ultraviolet lamp. The reverse osmosis unit's concentrate outlet is split into two routes: one route connects to the booster pump inlet via a booster throttle; the other route connects to a recovery tank via a sewage solenoid valve, with a water pipe equipped with a concentrate float switch. During water production, all concentrate is returned, and sewage is periodically discharged. After the system is shut down when full, the reverse osmosis membrane is cleaned using siphoning and natural osmosis. It is resistant to fouling and blockage, saves water and electricity, and meets Class I water efficiency standards according to water efficiency standard test conditions, fully meeting the national standard limit indicators for drinking water sources.

Description

Technical Field

[0001] The invention discloses a drinking water quality processor, in particular to a water-saving reverse osmosis water purifier capable of reusing wastewater and utilizing surplus energy. Background Art

[0002] Among deep drinking water purification technologies, reverse osmosis offers the highest precision, removing impurities as small as 0.0001 microns, efficiently removing inorganic and organic matter, and microorganisms. It possesses unique desalination capabilities and provides excellent sensory comfort. However, due to structural limitations, traditional household reverse osmosis water purifiers suffer from high water consumption, scaling, clogging, and secondary contamination.

[0003] Reverse osmosis membranes are non-porous, semipermeable membranes that are easily contaminated and clogged by retained scaling substances during the water production process. Their structural features differ from those of screening membranes; in addition to the raw water inlet and product water outlet, they also have a concentrate outlet. During water production, product water flows vertically out of the membrane, while a large amount of concentrate continuously flows horizontally across the membrane surface, flushing impurities trapped on the membrane surface before being discharged through the concentrate outlet to ensure water quality and proper operation of the equipment. The product technical manual stipulates that the recovery rate of produced (purified) water from a single household reverse osmosis membrane (referred to as "membrane") is 15%. Improperly increasing the recovery rate will inevitably lead to increased feed water (concentrate side) concentration, reduced water flux, and increased scaling, which can lead to membrane clogging. Household reverse osmosis water purifiers (referred to as "water purifiers") typically utilize a single membrane configuration, resulting in low recovery rates.

[0004] According to the National Water Conservation Standards Technical Committee, nearly 40% of household reverse osmosis water purifiers on the market currently have a water yield of less than 20%, with a significant amount of concentrated water being discharged as wastewater. Recovery rate is linearly correlated with feed water concentration: higher recovery rates and higher concentration coefficients increase scaling susceptibility; conversely, lower recovery rates and lower concentration coefficients decrease scaling susceptibility. Scaling and clogging are key obstacles hindering the ability of reverse osmosis water purifiers to improve recovery rates, reduce water consumption, and expand their application.

[0005] In response to the prominent problem of high water consumption and waste of water resources caused by reverse osmosis water purifiers, my country's first mandatory national standard for water purification industry, GB 34914 "Water Efficiency Limit Values and Water Efficiency Grades of Reverse Osmosis Water Purifiers" was released in 2018 (abbreviated as: water efficiency standard).

[0006] Table 1 Water efficiency grade standards for water purifiers and concentrate coefficients for single membrane water purifiers

[0007]

[0008] Note: (1) Water efficiency level 2 is the water-saving evaluation value, and level 5 is qualified. (2) The effect of the salt content of the purified water on the concentration coefficient is negligible.

[0009] Reverse osmosis is the nemesis of hard water and brackish water, but it can also become contaminated and clogged. With the significant increase in national standards for water efficiency limits and water conservation ratings, it is addressing the challenges of hard, salty, and highly concentrated water, while enhancing its anti-fouling and anti-clogging capabilities.

[0010] Scale is generally divided into three categories: salt scale, formed by insoluble salts such as calcium and magnesium bicarbonates and sulfates; fouling, formed by suspended solids and colloids such as silt, humus, and metal oxides; and slime, formed by biological sludge such as bacteria and algae. Currently, the following technical measures are available to address the problem of reverse osmosis membrane fouling in water purifiers:

[0011] Dirt and sticky dirt: can be solved by using fiber cotton (PP), microfiltration (MF), ultrafiltration (UF), activated carbon, pretreatment and antibacterial methods.

[0012] Salt scale: This can be addressed with chemical and physical methods such as softening and scale inhibition. The resin softening process requires frequent regeneration, is cumbersome to operate, and consumes a lot of water, making it difficult to use at home. The increased sodium content after regeneration can negatively impact human health if consumed in the long term. Currently, most water purifiers use "silicon phosphate essence" as a scale inhibitor. Using too little is ineffective, while excessive use can cause pipe blockages and excessive phosphate levels, making it unsuitable for long-term drinking.

[0013] Anti-pollution reverse osmosis membrane: By improving the membrane surface roughness, electrical neutrality, high hydrophilicity, and wide water flow channel, it inhibits the adsorption of microorganisms and organic matter on the membrane surface, has a good effect in reducing pollutant deposition, but has a poor effect on salt scale.

[0014] In recent years, physical and chemical anti-scaling and descaling methods such as ultrasound, electromagnetic field, electric field, and electrosorption have become the development direction of international green and environmentally friendly water treatment technologies. However, due to technical and cost reasons, they have not yet been found in water purifiers.

[0015] Multiple membranes in series, partial brine circulation, and pulse flushing are effective methods for preventing fouling and clogging and improving recovery rates. However, these methods are still insufficient in terms of preventing fouling and clogging, saving water and reducing consumption, lowering costs, and expanding the applicable water sources. Currently, water efficiency standards cannot fully cover the limit indicators for high-salt, high-hardness, and low-quality water sources in GB 5749, "Sanitary Standard for Drinking Water." Summary of the Invention

[0016] The purpose of the present invention is to further improve the anti-fouling and anti-blocking effects of existing reverse osmosis water purifiers, achieve full coverage of the limit indicators of drinking water sources for reverse osmosis water purifiers, and solve the drinking water needs of different regions and different water sources, especially for poor-quality water sources in high-hardness, high-salt, high-alkali, and arid areas with little rain. To achieve the above-mentioned purpose, the present invention combines basic theories and practices such as energy recovery, natural osmosis and reverse osmosis, water chemistry, and hydraulics, reuses wastewater, utilizes surplus energy, reduces resistance and increases flow, and strengthens flushing. It eliminates a number of conventional standard configurations with high resistance, high energy consumption, and the presence of secondary pollution, constructs a new circuit and water system, and develops a high-efficiency reverse osmosis water purifier that uses physical methods to solve the problems of anti-fouling and anti-blocking.

[0017] The technical solution adopted by the present invention to solve the technical problem is:

[0018] (1) The overall structure of the product consists of a pretreatment system, a reverse osmosis device, a water production and concentrated water circulation flushing system, a sewage flushing system, a water production osmosis cleaning system, a water level control system, a water tank and sterilization system, a concentrated water recovery system, and a circuit control system.

[0019] (2) The pretreatment system consists of a water inlet solenoid valve, a granular activated carbon filter bottle, a compressed activated carbon filter bottle, a fine fiber cotton filter bottle, and a booster pump. The inlet and outlet of the reverse osmosis device's purified water and concentrated water are connected with high-flow, low-resistance pipe fittings to streamline the water path. Conventional standard equipment such as pressure water storage tanks, post-activated carbon, high-pressure switches, one-way valves, wastewater ratios, right-angle elbows, and pipe plug joints, which have high resistance, high energy consumption, and the potential for secondary pollution, are eliminated.

[0020] (3) The concentrated water outlet of the reverse osmosis device is divided into two routes: one route is connected to the water inlet of the booster pump suction process through a pipe through the booster throttle, and the other route is inserted into the recovery barrel through the sewage solenoid valve with a water pipe with a concentrated water float switch, forming a water production and concentrated water circulation flushing system and a concentrated water recovery system.

[0021] (4) The water production and concentrated water circulation flushing system and sewage flushing system change the conventional process of discharging all concentrated water or partially returning it to a process of returning all concentrated water and periodically discharging sewage, so that the concentrated water (wastewater) accounting for 2 / 3 of the total water volume is recycled and reused, and the useless work accounting for 1 / 2 of the total energy consumption is converted into the kinetic energy of flushing water: when producing water, the sewage solenoid valve is closed, and the concentrated water enters the booster pump through the high-speed water flow of the booster throttle, and resonates with the pulse function unique to the diaphragm booster pump, generating a pulsating turbulent flow with greater disturbance force to circulate and flush the reverse osmosis membrane, effectively inhibiting the deposition and attachment of dirt and preventing membrane clogging; when discharging sewage, the sewage solenoid valve is opened, the booster pump load is released and runs at full speed, and the impurities attached to the membrane surface are flushed clean with the maximum water flow, and the high-concentration concentrated water is replaced with new raw water.

[0022] (5) The water production and concentrated water circulation flushing system and the sewage flushing system increase the pump output through the synergistic effect of wastewater reuse and surplus energy utilization. For example, the rated total water volume of a 400G water purifier is 2700ml / min / 0.5Mpa. Through wastewater reuse and surplus energy utilization, the total water volume is increased to 3000-3500ml / min / 0.7Mpa. The latter has a heavier load than the former, but the pump output is increased by 11%-29.6%.

[0023] (6) The water production and concentrated water circulation flushing system and the sewage flushing system. The flushing water volume is large and the flow rate is high. For example, the standard flow rate of the wastewater of a 400G water purifier is 1100 ml / min, and the concentrated water circulation flushing water flow rate is 2000-2500 ml / min. The latter is 82%-127% higher than the former.

[0024] (7) The water production and concentrated water circulation flushing system and the sewage flushing system are controlled by two timing modules of the cycle time relay. Water production and sewage flushing are alternately circulated. Each cycle lasts 30 to 90 seconds for water production and 3 to 15 seconds for sewage discharge. The water production and sewage discharge time ratio is 1:0.05 to 1:0.25. The shorter the water production time and the longer the sewage discharge time within the cycle, the lower the probability of reverse osmosis membrane contamination. Conversely, the longer the water production time and the shorter the sewage discharge time, the higher the probability of contamination. Statistical analysis is used to optimize operating parameters according to different water qualities.

[0025] (8) The water permeation cleaning system is composed of a water tank, a signal timing module, a cleaning timing module, a cleaning relay, and a sewage solenoid valve. After the water is full and the system is shut down, the water inlet solenoid valve is closed and the sewage solenoid valve is opened. When the pressure on the membrane inlet side is less than the water level gravity of the water tank, the clean water in the water tank flows back to the membrane outlet side through the pipe using the siphon and concentration difference natural permeation principle, and the membrane outlet side permeates to the water inlet side. The solubility characteristics of water (especially high-purity water) are used to dissolve, loosen, peel off, and remove the dirt accumulated on the surface and deep layer of the membrane, thereby restoring the water flux of the membrane and extending its service life. It effectively copes with high-salt, high-hardness, high-alkali and low-quality water sources and has obvious effects. The water consumption of water permeation cleaning accounts for 3‰ of the total water production.

[0026] (9) The water level control system is composed of a water level relay and a float water level switch: the rise and fall of the water level controls the on-off of the float switch, which controls the on-off of the water level electronic probe, which controls the on-off of the water level relay, which controls the start, standby, and shutdown of the system. Its advantages are that the electronic probe does not come into contact with the water, thus eliminating electrochemical corrosion and contamination, and the water level relay electronic probe is weakly powered to prevent the float switch contacts from sticking.

[0027] (10) The water tank and sterilization system. It consists of a stainless steel gravity water tank and an ultraviolet sterilization lamp, eliminating the disadvantages of traditional pressure water tanks in generating back pressure, reducing production capacity, and causing secondary pollution. It fully utilizes the gravity of the water level, without the hazard of back pressure, and the water intake flow rate is ≥4L / min, which is faster than that of pressure water storage tanks and increases production capacity by 20%~25%. The immersion ultraviolet sterilization lamp starts synchronously with water production, has a long irradiation time, and utilizes the mirror reflection of the stainless steel water tank. The ultraviolet killing intensity (CT value) is more than 600 times higher than that of the existing water purifier flow-through ultraviolet lamp.

[0028] (11) The circuit control system is composed of a water production and sewage discharge circuit, a water production and osmotic cleaning circuit, a water level control circuit, a concentrated water recovery circuit, a filter element service life control circuit, and a water shortage protection circuit. It realizes the full automation of the production process of water production, sewage discharge, osmotic cleaning, concentrated water recovery, filter element monitoring, disinfection and sterilization, and water shortage protection.

[0029] (12) The circuit control system. Based on the raw water quality characteristics such as total dissolved solids (salt content, salinity, TDS), total hardness, alkalinity, turbidity, and recovery rate, desalination rate, water purity, water consumption, equipment capacity and other factors, the operating parameters of different water qualities, different working conditions, and different water requirements are optimized and integrated into four parts: water production, sewage discharge, self-cleaning, and pressure. The optimal balance point is found, and the four parts complement each other to form a synergistic force. The same machine is suitable for both low-salt and low-hardness water and high-salt and high-hardness water. It has high versatility for different regions, different water qualities, and different environments. Water quality testing can be completed in just over ten minutes using simple methods such as TDS pens and test kits, and operating parameters can be set on site.

[0030] (13) Functional stability test. Based on the GB 34914 "Limited Values and Grades of Water Efficiency for Reverse Osmosis Water Purifiers" and the Ministry of Health's "Safety and Functional Evaluation of Reverse Osmosis Treatment Equipment for Drinking Water (Draft for Comments)", all technical indicators were verified to be qualified. The functional stability indicators were superior to those specified in the relevant standards and the "Product Technical Manual".

[0031] Table 2 Reverse osmosis water purifier normative technical parameters and measurement data

[0032]

[0033] Note: The functional stability index parameters refer to the "Product Technical Manual", namely: water flow rate decrease rate, desalination rate fluctuation rate, working pressure increase rate, which mainly characterize the clogging condition of the membrane.

[0034] (14) Water efficiency test. According to the water efficiency standard test conditions, the water efficiency standard of the first level was achieved, and the national standard limit indicators of drinking water sources were fully covered.

[0035] Table 3 Drinking water source standard limit index reverse osmosis water purifier water efficiency test parameters

[0036]

[0037] The beneficial effects of this invention are that, instead of conventional complete discharge or partial return of concentrated water, it is replaced with complete return plus periodic blowdown, allowing the concentrated water, which accounts for two-thirds of the total water volume, to be recycled and reused, converting the useless work, which accounts for half of the total energy consumption, into effective work. Physical methods are used to prevent fouling and blockage, saving water and reducing energy consumption, achieving Class 1 water efficiency as specified in GB 34914, "Limited Values and Grades of Water Efficiency for Reverse Osmosis Water Purifiers," with all indicators consistently meeting standards. This achieves full coverage of the water efficiency standards for high-salt, high-hardness, and low-quality water sources specified in GB 5749, "Sanitary Standard for Drinking Water," and the technical solutions employed are applicable to reverse osmosis water purifiers for household and similar uses. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0039] Figure 1 is a schematic diagram of the process flow of the present invention. In the diagram: 1. Water source ball valve, 2. Water inlet solenoid valve, 3. Granular activated carbon filter bottle, 4. Compressed activated carbon filter bottle, 5. Fine fiber cotton filter bottle, 6. Low-pressure switch, 7. Booster pump, 8. Booster restrictor, 9. Reverse osmosis unit, 10. Sewage discharge solenoid valve, 11. Water level relay, 12. Upper water level float switch, 13. Lower water level float switch, 14. Ultraviolet lamp, 15. Water tank, 16. Faucet, 17. Concentrate float switch, 18. Recovery tank.

[0040] Figure 2 is a schematic diagram of the circuit of the present invention. The diagram includes a transformer TC, a start button SB, a power indicator LED1, a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, a start relay KA1, a concentrated water float switch SQ1, an upper water level float switch SQ2, a lower water level float switch SQ3, an accumulation relay SL, an intermediate relay KA2, a signal timing module MT1, a buzzer HA, a cleaning timing module MT2, a sewage discharge relay KA3, a sewage discharge indicator LED2, a water level relay CL, a water inlet solenoid valve Y1, a low-pressure switch SP, a cycle timer relay DH, a main control relay KA4, a booster pump M, an ultraviolet lamp UF, and a sewage discharge solenoid valve Y2. DETAILED DESCRIPTION

[0041] In Figure 1: the water source ball valve 1, water inlet solenoid valve 2, granular activated carbon filter bottle 3, compressed activated carbon filter bottle 4, fine fiber cotton filter bottle 5, and booster pump 7 are connected to each other in sequence with large-diameter, low-resistance pipe fittings. The booster pump is connected in parallel with the low-pressure switch 6 to form a pretreatment system. The water inlet of the reverse osmosis device 9 is connected to the booster pump outlet with a pipe, and the clean water outlet is connected to the water inlet of the water tank 15 with a pipe extending to the bottom of the water tank. The water tank is a gravity-type box with a faucet 16 at the bottom. The water intake flow rate is ≥4L / min. The water tank is equipped with an upper water level float switch 12 and a lower water level float switch 13 controlled by a water level relay 11. The ultraviolet lamp 14 is installed on the central axis of the water tank. The lower part of the water tank should be installed in a horizontal line with the reverse osmosis device. The back pressure on the membrane caused by the backflow of clean water to the reverse osmosis device should be less than 300 mm / h2o, which is 3% of the allowable back pressure.

[0042] The concentrated water outlet of the reverse osmosis device is divided into two routes. One route is connected to the water inlet of the booster pump through the booster throttle 8 with a pipe, and the other route is connected to the water pipe with the concentrated water float switch 17 through the sewage solenoid valve 10 and inserted into the recovery bucket 18. The system consists of a water production and concentrated water circulation flushing system, a sewage flushing system and a concentrated water recovery system. When producing water, the sewage solenoid valve is closed, and the concentrated water passes through the power throttle and merges with the suction inlet of the booster pump to resonate through the pulse water flow of the diaphragm booster pump, generating a pulsating turbulent flow with greater disturbance force to circulate and flush the reverse osmosis membrane, inhibiting the deposition and adhesion of dirt and preventing membrane blockage. When discharging sewage, the sewage solenoid valve is opened, and the booster pump is unloaded and runs at full speed, using the maximum water flow to flush out impurities attached to the membrane surface, replacing high-concentration concentrated water with new raw water, and water production and sewage discharge are carried out alternately. After the water is full and the machine is shut down, the water inlet solenoid valve is closed and the sewage solenoid valve is opened. The clean water flows back from the water tank through the pipe to the outlet side of the membrane using the siphon and natural paint penetration principle, and then permeates from the outlet side to the inlet side and is discharged through the sewage solenoid valve, forming a water production and permeation cleaning system.

[0043] The AC 220V power supply is connected to the power line of transformer TC. The positive DC24V output of the transformer is connected to three lines: line 1 to the start button SB, line 2 to the neutral line of the start relay KA1 and in parallel with the power indicator LED1, and line 3 to the coil terminal of the water level relay CL. The negative DC24V output is connected in parallel with the start maintenance device, power indicator, cumulative time relay SL, water level relay, intermediate relay KA2, cycle time relay DII, main control relay KA4 coil, and the negative terminals of the water inlet solenoid valve Y1, sewage solenoid valve Y2, power indicator, and sewage indicator LED2. The positive DC24V output terminal of the transformer is connected to the start button and then to the start relay coil terminal via the first diode D1. Its normally open contact KA1.2 is connected to the start relay coil terminal via the normally closed contact of the concentrated water float switch SQ1, forming the start relay self-locking circuit.

[0044] The normally open contact KA1.1 of the starting relay is connected in parallel with the power supply and output terminal SL3.4 of the accumulation time relay. The normally closed contact of the power supply and output terminal SL3.4 of the accumulation time relay is connected to the neutral terminal of the water level relay. The normally open contact CL1 of the water level relay is connected in parallel with the upper normally open contact input terminal SP of the water inlet solenoid valve and the low-pressure switch. The lower normally closed contact output terminal SP is connected in parallel with the coil and neutral terminal of the cycle time relay. The normally closed contact DH2 is connected to the coil terminal of the main control relay KA4. The first group of normally open contacts KA4.1 of the main control relay controls the boost pump M, the second group of normally open contacts KA4.2 controls the AC220V ultraviolet lamp UF, and the normally closed contact KA4.3 is connected to the counting terminal SL8.9 of the accumulation time relay. The normally open contact DH1 of the cycle time relay is connected in parallel with the sewage discharge solenoid valve and sewage discharge indicator light through the third diode D3. The normally open contact DH1 of the cycle time relay is connected to the normally closed contact DH2. A fourth diode D4 is connected between them to form a water production and concentrated water circulation flushing and sewage flushing circuit.

[0045] The DC12V positive terminal SL6 of the accumulation relay output is connected in parallel to the positive terminal MT1.V+ of the signal timing module MT1 and the positive terminal MT2.V+ of the cleaning timing module MT2. The DC12V negative terminal SL.9 of the accumulation relay is connected to the normally open contact KA2.2 of the intermediate relay KA2 and is divided into two paths: one is connected to the negative terminal of the signal timing module and the trigger terminal MT1.V-1, and the other is connected to the negative terminal of the cleaning timing module and the trigger terminal MT2.VI. The DC12V positive output terminal MT1.OVI of the signal timing module is connected to the positive terminal of the buzzer HA, and the DC12V positive output terminal MT2.OVI of the cleaning timing module is connected to the coil terminal of the sewage discharge relay KA3. The DC12V negative terminal of the sewage discharge relay coil and the DC12V negative terminal of the buzzer are connected to the negative terminal of the accumulation relay. The input line of the normally open contact KA3.1 of the sewage discharge relay is connected to the normally closed contact CL2 of the water level relay. The outgoing line is connected in parallel with the sewage discharge solenoid valve and sewage discharge indicator light through the second diode D2 to form a signal and water production permeation cleaning circuit;

[0046] The water level control system consists of a water level relay, an upper water level float switch SQ2, a lower water level float switch SQ3, and an intermediate relay. The upper water level electronic probe A of the water level relay is connected to the normally open contact input of the upper water level float switch SQ2, and the lower water level electronic probe C is connected to the normally open contact input of the lower water level float switch SQ3. The output wires from the upper and lower water level float switches are combined into a common center line for the upper and lower floats, which is then connected to the middle water level electronic probe B via the normally open contact KA2.1 of the intermediate relay. The rise and fall of the water tank water level controls the on / off of the float switch, which in turn controls the on / off of the water level relay electronic probe. The on / off of the electronic probe controls the on / off of the water level relay contacts, which in turn controls the on / off of the water level relay contacts. The on / off of the water level relay contacts controls the start, standby, and shutdown modes of the system. The electronic probes are isolated from water to prevent electrochemical corrosion and contamination. The low-voltage electronic probes prevent the float switch contacts from sticking.

[0047] The concentrated water float switch 17 is installed at the end of the concentrated water pipe. The input and output lines of its normally closed contact QSI are connected in series to the self-locking circuit of the starting relay, forming a concentrated water recovery circuit; the counting terminal SL8.9 of the cumulative relay is connected to the normally closed contact KA4.3 of the starting relay, forming a filter element service life control circuit: the normally open contact of the water level relay is connected to the input line of the low-pressure switch, and the output line of the low-pressure switch is connected in parallel with the power terminal and neutral terminal of the cycle time relay, forming a water shortage protection circuit.

[0048] According to the raw water's total dissolved solids, total hardness, alkalinity, and turbidity water quality characteristics, the operating parameters are set through the cumulative time relay, cycle time relay, signal timing module, and cleaning timing module. The following operating parameters are set through digital programming: water production 30 to 90 seconds, sewage discharge 3 to 15 seconds, and permeation cleaning 10 seconds to 24 hours: the water production and sewage discharge time ratio is 1:0.05 to 1:0.25, the pressure is 0.5 to 0.75 MPa, and the filter element service life is 1500 to 2500 hours.

[0049] The implementation method is further explained below in conjunction with the operation of the equipment.

[0050] During water supply, there's no water in the tank. The normally open contacts of the upper and lower water level float switches are both disconnected, and the upper, middle, and lower electronic probes of the water level relay controlled by them are also disconnected (water supply). Open the water source ball valve and connect the transformer to power. The positive 24V DC current flows through three paths: 1 to the start button, 2 to the start relay's center line and the power indicator light, and 3 to the coil terminals of the water level maintenance device. The negative 24V DC current connects to the start relay, power indicator light, cumulative time relay, water level relay, intermediate relay, cycle time relay, main control relay coil, and the negative terminals of the water inlet solenoid valve, sewage solenoid valve, power indicator light, and sewage indicator light. The negative 12V DC current connects to the sewage relay coil and the negative terminal of the buzzer. When the start button is pressed, current flows through the first diode D1 to the start relay coil terminals, closing its normally open contacts. The current then splits into two paths: one, through the normally closed contacts of the concentrated water float switch, to the start relay coil terminals, energizing the start relay's self-locking circuit. The other, through the normally open contact KA1.1, supplies power to the power terminals of the accumulation relay. When the start button is released, the self-locking circuit causes the start relay to resume operation, and the first diode D1 reversely blocks the start relay coil current from flowing to the start button.

[0051] After the cumulative time relay is energized, its normally closed contact SL3.4 is in a closed state, supplying power to the neutral terminal of the water level relay. The normally open contact of the water level relay is closed, supplying power to the water inlet solenoid valve and the normally open contact of the low-pressure switch. The water inlet solenoid valve opens, and the water pressure causes the normally open contact of the low-pressure switch to close and supply power to the coil terminal and the neutral terminal of the cycle time relay. The normally closed contact of the cycle time relay is closed and supplies power to the coil terminal of the main control relay. The normally open contact KA4.1 of the main control relay is closed to start the booster pump to make water. The normally open contact KA4.2 is closed to light up the ultraviolet lamp, and the normally closed contact KA4.3 disconnects the counting terminal of the cumulative time relay controlled by it, disconnecting the cumulative time count until the timing ends.

[0052] After the water production timing of the cycle time relay ends, its normally closed contact opens and its normally open contact closes, instantly switching from the water production circuit DH2 to the sewage discharge circuit DH1. Power is supplied to the sewage discharge solenoid valve through the third diode D3 to discharge concentrated water, and the sewage discharge indicator light comes on; at the same time, the sewage discharge circuit supplies power to the water production circuit through the fourth diode D4, and the booster pump and ultraviolet lamp controlled by it continue to operate, entering the sewage flushing program until the sewage discharge timing ends, the sewage discharge solenoid valve closes, the sewage discharge indicator light goes out, and the water production program is entered again: water production-sewage discharge-water production cycle is repeated until the water is full and the machine stops; during sewage discharge, the current supplies power to the water production circuit through the fourth diode D4, reversely blocking the current leakage from the water production circuit to the sewage discharge circuit.

[0053] When making water, the sewage solenoid valve is closed, and the concentrated water passes through the booster throttle and merges with the water inlet of the booster pump suction process, and resonates with the pulse water flow of the diaphragm booster pump to form a pulsating turbulent flow, which circulates and flushes the reverse osmosis membrane: when discharging sewage, the sewage solenoid valve is opened, and the booster pump is unloaded and runs at full speed, and the impurities attached to the membrane surface are flushed clean with the maximum water flow.

[0054] During the water production process, when the water level in the water tank rises to the point where the normally open contact of the lower water level float switch is closed and the middle and lower water level electronic probes of the water level relay are connected, but the normally open contact of the upper water level float switch, the upper water level electronic probe of the water level relay, and the normally open contact of the water level relay are still disconnected, the water purifier is still in the water production and circulating sewage discharge state; when the water level is full and rises to the point where the normally open contact of the upper water level float switch is closed, the upper, middle, and lower water level electronic probes of the water level relay are connected to each other, the normally open contact of the water level relay is disconnected, and the water inlet solenoid valve, low-pressure switch, and the circulating relay, main control relay, booster pump, and ultraviolet lamp controlled by them all lose power, and water production stops.

[0055] At the moment the normally open contact of the water level relay is disconnected, its normally closed contact closes, supplying power to the coil terminal of the intermediate relay. The normally open contact of the intermediate relay closes, and the DC12V negative power supply controlled by it supplies power to the signal timing module and the sewage timing module at the same time: the signal timing module is triggered, and the DC12V positive current passes through its output terminal to supply power to the buzzer and sound the whistle until the timing ends; at the same time, the sewage timing module is triggered, and the DC12V positive current passes through its output terminal to supply power to the sewage relay coil terminal. The normally open contact of the sewage relay closes, and the second diode D2 The DC24V current output by the normally closed contact of the water level relay is transmitted to the sewage solenoid valve, the sewage solenoid valve is opened, and the sewage indicator light is on; the clean water uses the siphon and natural osmosis principle to flow back from the water tank through the pipe to the water outlet side of the membrane, and then permeates from the water outlet side to the water inlet side, and is discharged through the sewage solenoid valve. The solubility characteristics of water are used to dissolve, loosen, peel off and remove the dirt accumulated on the surface and deep layer of the membrane, restore the water flux of the membrane to extend its service life, and enter the water production penetration cleaning program. Until the timing ends, the sewage solenoid valve is closed and the sewage indicator goes out: the third diode D3 and the second diode D2 reversely block the water production penetration cleaning circuit current will not jump to the water production and sewage circuit, and the water production and sewage circuit current will not jump to the water production and penetration cleaning circuit.

[0056] During water use, when the water level in the water tank drops to the upper water level float switch, its normally open contact is disconnected, and the upper and middle water level electronic probes of the water level relay are disconnected, but the middle water level electronic probe and the lower water level electronic probe controlled by the normally open contact of the intermediate relay are still connected, and the normally open contact of the water level relay is still disconnected. The water purifier is in the water production, penetration cleaning and water use state and will not start automatically.

[0057] When the water level in the water tank drops to the lower water level, the normally open contact of the float switch is disconnected. At this time, the upper, middle and lower water level electronic probes of the water level relay are all disconnected, and the normally open contact of the water level relay is closed, and the water supply state is switched to.

[0058] When the concentrated water recovery water is full, the normally closed contact of the concentrated water float switch is disconnected, and the self-locking circuit of the starting relay controlled by it is disconnected and shut down.

[0059] The relay has a power-off memory function during accumulation. The running time of the booster pump is recorded through the opening and closing of its counting terminal and the normally closed contact of the start relay. The accumulated running time of the booster pump is converted into the service life of the filter element. When the service life expires, the power will be automatically cut off and the system will be shut down.

[0060] During the water production process, if the water pressure is insufficient due to water outage or filter blockage, the normally open contacts of the low-pressure switch will be disconnected, and the cycle time relay and main control relay controlled by it will lose power and shut down.

Claims

1. A water-saving reverse osmosis water purifier for wastewater reuse and surplus energy utilization, characterized by: It includes a water source ball valve, a water inlet solenoid valve, a granular activated carbon filter bottle, a compressed activated carbon filter bottle, a fine fiber cotton filter bottle, and a booster pump, which are connected to each other with pipe fittings in sequence, and the booster pump is connected in parallel with the low-pressure switch; The water inlet of the reverse osmosis device is connected to the outlet of the booster pump with a pipe. The purified water outlet of the reverse osmosis device is connected to the water inlet of the water tank with a pipe and extends to the bottom of the water tank. The concentrated water outlet of the reverse osmosis device is divided into two ways. One way is connected to the suction inlet of the booster pump with a pipe through the booster throttle, and the other way is connected to the water pipe with the concentrated water float switch through the sewage solenoid valve and inserted into the recovery bucket. The water tank is equipped with an upper water level float switch and a lower water level float switch controlled by a water level relay. The circuit system includes the transformer DC24V positive pole leading to three routes: route 1 to the start button SB, route 2 to the neutral line of the start relay KA1 and connected in parallel with the power indicator LED1, and route 3 to the coil terminal of the water level relay CL; the DC24V negative pole is connected in parallel with the start relay, power indicator, cumulative time relay SL, water level relay, intermediate relay KA2, cycle time relay DH, main control relay KA4 coil and the negative terminals of the water inlet solenoid valve Y1, sewage discharge solenoid valve Y2, power indicator LED1, and sewage discharge indicator LED2; During accumulation, the relay output DC12V positive terminal SL6 is connected in parallel with the positive terminal MT1.V+ of the signal timing module MT1 and the positive terminal MT2.V+ of the cleaning timing module MT2; during accumulation, the relay DC12V negative terminal SL9 is connected to the normally open contact KA2.2 of the intermediate relay KA2 and is divided into two paths: one path is connected to the negative terminal of the signal timing module and the trigger terminal MT1.VI, and the other path is connected to the negative terminal of the cleaning timing module and the trigger terminal MT2.VI.

2. The water-saving reverse osmosis water purifier for wastewater reuse and surplus energy utilization according to claim 1 is characterized by: The water tank is a gravity-type box with a faucet at the bottom. The water intake rate is ≥4L / min. The ultraviolet lamp is installed on the central axis of the water tank. The lower part of the water tank installation position should be on the same horizontal line as the reverse osmosis device. The back pressure on the membrane caused by the clean water flowing back to the reverse osmosis device should be less than 300 mm / water column, which is 3% of the allowable back pressure.

3. The water-saving reverse osmosis water purifier for wastewater reuse and surplus energy utilization according to claim 1 is characterized in that: the transformer The DC24V positive output terminal is connected to the start button and then to the start relay coil terminal via the first diode D1. Its normally open contact KA1.2 is connected to the start relay coil terminal via the normally closed contact SQ1 of the concentrated water float switch, forming a start relay self-locking circuit; The start relay's normally open contact KA1.1 is connected in parallel with the power supply and output terminal SL3.4 of the cumulative time relay. The normally closed contact of the power supply and output terminal SL3.4 of the cumulative time relay is connected to the neutral terminal of the water level relay. The water level relay's normally open contact CL1 is connected in parallel with the upper normally open contact input terminal SP of the water inlet solenoid valve and low-pressure switch. Its normally open contact output terminal SP is connected in parallel with the coil and neutral terminal of the cycle time relay. Its normally closed contact DH2 is connected to the coil terminal of the main control relay KA4. The main control relay's first set of normally open contacts KA4.1 controls the booster pump M, and the second set of normally open contacts KA4.2 controls the AC220V ultraviolet lamp UF. The normally closed contact KA4.3 is connected to the counting terminal SL8.9 of the cumulative time relay. The normally open contact DH1 of the cycle time relay is connected in parallel with the sewage discharge solenoid valve and the sewage discharge indicator light through the third diode D3. A diode D4 is connected between the normally open contact DH1 and the normally closed contact DH2 of the cycle time relay to form a water production and concentrated water circulation flushing and sewage discharge circuit; The DC12V positive output terminal MT1.OVT of the signal timing module is connected to the positive pole of the buzzer HA, and the DC12V positive output terminal MT2.OVT of the cleaning timing module is connected to the coil terminal of the sewage discharge relay KA3; the DC12V negative pole of the sewage discharge relay coil and the DC12V negative pole of the buzzer are connected to the DC12V negative terminal SL9 of the cumulative time relay; the input line of the normally open contact KA3.1 of the sewage discharge relay is connected to the normally closed contact CL2 of the water level relay, and the output line is connected in parallel with the sewage discharge solenoid valve and the sewage discharge indicator light through the second diode D2, forming a signal and water production penetration cleaning circuit.

4. The water-saving reverse osmosis water purifier for wastewater reuse and surplus energy utilization according to claim 1 is characterized by: The water level control system consists of a water level relay + upper water level float switch SQ2, lower water level float switch SQ3 + intermediate relay: The upper water level electronic probe A of the water level relay is connected to the normally open contact input of the upper water level float switch SQ2, and the lower water level electronic probe C is connected to the normally open contact input of the lower water level float switch SQ3. The output wires of the upper and lower water level float switches are combined into a common neutral line for the upper and lower floats, which is then connected to the middle water level electronic probe B via the normally open contact KA2.1 of the intermediate relay. The rise and fall of the water tank water level controls the on-off of the float switch, which controls the on-off of the water level relay electronic probe, which controls the on-off of the water level relay contacts. The on-off of the water level relay contacts controls the on-off of the power supply. The electronic probe does not come into contact with water to prevent electrochemical corrosion and pollution. The electronic probe is weak current to prevent the float switch contacts from sticking.

5. The water-saving reverse osmosis water purifier for wastewater reuse and surplus energy utilization according to claim 1 is characterized by: The concentrated water float switch is installed at the end of the concentrated water pipe, and its normally closed contact SQ1 input and output lines are connected in series to the self-locking circuit of the starting relay to form a concentrated water recovery circuit; the cumulative time relay counting terminal SL8.9 is connected to the normally closed contact KA4.3 of the starting relay to form a filter element service life control circuit; the normally open contact of the water level relay is connected to the normally open contact input line of the low-pressure switch, and its normally open contact output line is connected in parallel with the power terminal and neutral terminal of the cycle time relay to form a water shortage protection circuit.

6. The water-saving reverse osmosis water purifier for wastewater reuse and surplus energy utilization according to claim 1 is characterized by: According to the water quality characteristics of raw water such as total dissolved solids, total hardness, alkalinity and turbidity, the operating parameters are set by digital programming through the cumulative time relay, cycle time relay, signal timing module and cleaning timing module: water production 30 to 90 seconds, sewage discharge 3 to 15 seconds, and osmotic cleaning 10 seconds to 24 hours; the ratio of water production and sewage discharge time is 1:0.05 to 1:0.25, the pressure is 0.5 to 0.75 MPa, and the filter element service life is 1500 to 2500 hours.

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