Heavy metal ion mineralization column, heavy metal ion mineralization water purifier and control method

Abstract

The present invention discloses a heavy metal ion mineralization column, a heavy metal ion mineralization water purifier, and a control method. The heavy metal ion mineralization water purifier consists of three parts: a water purification part, a backwash part, and a monitoring part. The water purification part mainly consists of a filter column, an anion exchange column, a metal ion super-mineralization column, and a water softening column, which are connected by pipes, and finally obtains pure water for human consumption; the backwash part uses a backwash agent to wash the material through the filter column, and the wastewater after washing flows directly into the sewer; the monitoring part is controlled by a heavy metal ion concentration monitoring device and a corresponding solenoid valve, and can provide real-time feedback of information to an associated mobile phone app. The water purifier organically combines water purification and automated control, and can be used for water purification with high efficiency and low cost. The process of treating raw water using the device is simple and easy to operate. At the same time, the water purifier can be monitored and controlled online, which is low in cost and meets market demand.

Description

Technical Field

[0001] The present invention belongs to the technical field of water treatment, and in particular relates to a heavy metal ion mineralization column, a heavy metal ion mineralization water purifier and a control method. Background Art

[0002] Currently, the drinking water consumed by Chinese residents basically comes from purified water from water plants. At present, more than 99% of my country's water plants still use conventional treatment methods, namely coagulation-sedimentation-filtration-chlorination disinfection purification process, and maintain a certain amount of residual chlorine in the water before delivering the water to users. This purification process mainly removes suspended matter, colloids and bacteria, and its efficiency in removing soluble organic matter is extremely low. Although chlorination disinfection kills bacteria in the water, once liquid chlorine combines with organic matter in the water, it will produce a large amount of organic halides (trihalomethanes, THMS), which account for the vast majority of synthetic organic matter in drinking water. Not only can the organic mutagens in the raw water not be removed, but they will increase exponentially.

[0003] At the same time, during the transportation process from the factory to consumers' homes, tap water inevitably experiences some contamination due to the aging of water distribution networks and other equipment. For example, as water flows through unlined metal pipes, fittings, and water tanks, pH and dissolved oxygen can cause severe corrosion on the pipe walls, resulting in large amounts of metal rust and excessive levels of metal ions in the water. Furthermore, the anti-rust paint inside pipes has very poor adhesion, typically fading after three to six months. Furthermore, the primary component of this paint is lead dioxide, which can easily lead to excessive levels of lead in the water. Furthermore, the aging and inadequate cleaning of secondary water supply systems in urban communities can easily lead to microbial, heavy metal, and organic contamination. Data from the Chinese Center for Disease Control and Prevention shows that the passing rate for 3,671 secondary water supply samples nationwide is only 80.8%. In addition to microbial and residual chlorine levels, heavy metal ions such as iron, turbidity, and visible contaminants are common among the main sources of excess water quality.

[0004] Since domestic water, including drinking water and cooking water, only accounts for 0.5%-2% of a city's water supply, it would be prohibitively expensive for waterworks to treat all of this water to high quality. Consequently, over the past decade, water purifiers, as a means of providing high-quality drinking water, have seen significant development both domestically and internationally. They address secondary contamination of tap water without the high cost of bottled water, making them a viable alternative to bottled water and a preferred choice for healthy household drinking water.

[0005] Depending on the water quality and needs, the mainstream household water purifiers currently available on the market mainly include coarse filtration, ultrafiltration water purifiers, RO reverse osmosis water purifiers, etc. These are generally multi-stage filter cartridge water purifiers, and are differentiated by the material of the product's core filter cartridge. The filter cartridge is mainly made of PP fiber cotton, activated carbon, American KDF (a copper-zinc alloy), ion exchange resin, UF ultrafiltration membrane, RO reverse osmosis membrane, etc. The PP cotton filter cartridge is made of non-toxic and odorless polypropylene. It has the characteristics of large flow rate, corrosion resistance, high pressure resistance, and low cost. It can remove large particles such as mud, rust, and algae from the water. The activated carbon filter cartridge can absorb solid impurities, residual chlorine, volatile organic compounds, odors, and some heavy metals. KDF is a high-purity copper-zinc alloy that can remove some heavy metals and acid ions in the water and improve the activation level of the water. Ion exchange resins are often used as water softener filters. They remove cations such as calcium and magnesium from raw water, improving the taste of water and resolving hard water softening issues. They also reduce the accumulation of metal ions in the human body, lowering the risk of kidney stones. Ultrafiltration membranes, made from a bundle of hollow fibers, typically have pore sizes ranging from 10 to 100 nm. They can remove rust, sediment, bacteria, viruses, and other impurities from water. They offer high water output, consume little electricity, and produce no wastewater, making them suitable for use in household central water purifiers. Nanofiltration membranes have even smaller pore sizes, reaching 1 to 2 nm, but they require high-pressure pumps to operate properly and are expensive. Reverse osmosis membranes, with pore sizes down to 0.1 nm, can remove virtually all impurities from water, resulting in pure water.

[0006] Heavy metal ions are highly toxic to the human body, and their small ion diameter has long been a challenge in water purification. Heavy metal ions are mostly smaller than 1 nm in diameter. Current technologies available for household water purifiers include activated carbon adsorption, electrochemical reactions using copper-zinc alloy (KDF), and filtration using reverse osmosis (RO) membranes. However, activated carbon's ability to adsorb heavy metal ions is limited and highly dependent on its quality, making it suitable only for coarse filtration. KDF electrochemical reactions can cause excessive copper and zinc ion levels in treated water, and its use in drinking water treatment has been explicitly banned in Japan. Besides activated carbon for adsorption and KDF for electrochemical redox and catalysis, the pore size of filter elements in filtration and membrane separation-based purification technologies determines their treatment capacity. Effective removal of heavy metal contamination in water requires a filtration precision smaller than the above-mentioned heavy metal ion diameters. RO reverse osmosis membranes, with pore sizes down to 0.1 nm, are virtually the only option for the water purifier industry to safely and effectively remove heavy metal ions. However, RO reverse osmosis water purifiers also have some unconcealable shortcomings. First, they are expensive. The current market price of RO reverse osmosis water purifiers is generally several thousand yuan, which is a mid-to-high-end product. Second, the RO reverse osmosis membrane has a short life and is easy to clog. The RO membrane designed by the company now has a service life of 3 to 5 years, but the actual application period is only 1 to 2 years, and the reverse osmosis membrane filter is easy to clog, which leads to a series of problems such as high failure rate, unstable water quality, and loud noise. Third, the water output is small, the wastewater volume is large, and the power consumption is relatively high. The current wastewater ratio of reverse osmosis water purifiers is about 1:3, that is, making a cup of pure water produces at least 3 cups of wastewater. The water utilization rate is low, resulting in waste of resources.

[0007] Therefore, how to develop a composite material that is low-priced, environmentally friendly, and has excellent adsorption performance is of great significance for solving problems in the field of water purifiers at home and abroad; at the same time, a low-cost water purifier can meet the living needs of ordinary families for purified water and has broad market prospects. Summary of the Invention

[0008] To address the high cost, low efficiency, and resource waste associated with heavy metal ion pollution purification in commercially available household water purifiers, we are developing a comprehensive suite of household water purifiers, leveraging our core technology to develop green, environmentally friendly composite materials with excellent adsorption properties. This intelligent household water purifier combines water purification with automated control, enabling efficient and cost-effective water purification. Furthermore, the raw water treatment process is simple and easy to operate, while also enabling online monitoring and control of the purifier.

[0009] In order to achieve the above technical objectives, the present invention provides the following implementation methods:

[0010] A heavy metal ion mineralization column for a water purifier, wherein the cavity of the heavy metal ion mineralization column is filled with a heavy metal adsorption material composed of amorphous iron oxyhydroxide nanoparticles loaded on the surface of porous silica gel balls between the inlet and the outlet.

[0011] The active material for adsorbing heavy metals such as arsenic, copper, lead, zinc, and chromium in the heavy metal adsorption material of the present invention is amorphous iron oxyhydroxide nanoparticles. Compared with general iron oxyhydroxide materials, amorphous iron oxyhydroxide nanoparticles have an amorphous crystal structure and show higher adsorption activity for heavy metals such as arsenic, copper, lead, zinc, and chromium in aqueous solution. In addition, the amorphous iron oxyhydroxide nanoparticles and porous silica gel balls have good affinity for water, which is conducive to their dispersion in water. Porous silica spheres, with their porous structure and large surface area, can be used as carrier materials to fully disperse and stably load amorphous iron oxyhydroxide nanoparticles onto their surfaces. This not only exposes more active adsorption sites on the amorphous iron oxyhydroxide nanoparticles, but also allows them to be physically adsorbed by the porous silica spheres, thereby enriching these heavy metals near the active substances of the amorphous iron oxyhydroxide nanoparticles. This assists in the adsorption of these heavy metals in aqueous solution, thereby achieving deep removal of these heavy metals. Furthermore, the porous silica spheres are safe and non-toxic, making them suitable for the removal of heavy metals such as arsenic, copper, lead, zinc, and chromium from drinking water without causing secondary pollution. Once loaded onto the porous silica spheres, the amorphous iron oxyhydroxide nanoparticles form micron-sized particles, which are easily recovered or used for loading into fixed columns.

[0012] In this embodiment, the diameter of the porous silica gel balls is 150 to 250 μm, the particle size of the amorphous ferric oxyhydroxide nanoparticles is 10 to 50 nm, and the ratio of the porous silica gel balls to the amorphous ferric oxyhydroxide nanoparticles is measured by a molar mass ratio of silicon in the porous silica gel balls to iron in the amorphous ferric oxyhydroxide nanoparticles of 10 to 20:1.

[0013] Utilizing the above-mentioned heavy metal ion mineralization column, the present invention also includes a heavy metal ion mineralization water purifier, including a water purification system, wherein the water purification system includes a multi-layer filter material column, an anion exchange column, a heavy metal ion mineralization column and a water softening column connected in series from the water inlet to the water purification pipe outlet. Utilizing the heavy metal ion mineralization column, the heavy metal ion mineralization water purifier of the present invention can effectively purify heavy metals in water. The materials used inside the water purifier device are relatively cheap, the preparation cost is low, and the material cost and use cost are far lower than the current drinking water purification process. Even if the subsequent water treatment still adopts a membrane process, the burden on the membrane can be greatly reduced and the service life of the membrane can be increased. The preparation of the heavy metal super-strong mineralization composite material is simple and easy to obtain, and it is an adsorption material with excellent adsorption performance and is green and environmentally friendly. It can achieve super-strong mineralization and efficient removal of heavy metal ions, while making up for the defects of the high price, short life, and large amount of wastewater of the reverse osmosis membrane. It has great application potential in the field of household water purifiers.

[0014] In this embodiment, the filtration pore size of the multi-layer filter column can filter particles of 1 μm.

[0015] In this embodiment, a water inlet solenoid valve is provided on the water inlet pipe.

[0016] In this embodiment, a backwashing system is further included, which is connected to the multi-layer filter column, the anion exchange column, the heavy metal ion mineralization column and the water softening column through pipelines for backwashing.

[0017] In this embodiment, the backwash system includes a reagent A tube and a reagent B tube, and the multi-layer filter column, anion exchange column, heavy metal ion mineralization column and water softening column are respectively provided with a backwash inlet pipe and a backwash outlet pipe. The outlet of the reagent B tube and the outlet of the reagent A tube are respectively connected to four three-way solenoid valves and then connected to the backwash inlet pipes corresponding to the multi-layer filter column, anion exchange column, heavy metal ion mineralization column and water softening column respectively. The backwash outlet pipe is connected to the sewer pipe through a backwash drainage solenoid valve.

[0018] In this embodiment, the backwash outlet pipes of the multi-layer filter column, anion exchange column, heavy metal ion mineralization column and water softening column are grouped into two and are respectively connected to the sewer pipe through a three-way backwash drainage solenoid valve.

[0019] In this embodiment, a monitoring system is also included, which includes a PLC, a purified water heavy metal ion concentration monitoring device and a backwash water heavy metal ion concentration monitoring device. The purified water heavy metal ion concentration monitoring device is installed on the clean water pipe, and the backwash water heavy metal ion concentration monitoring device is installed on the sewer pipe. The purified water heavy metal ion concentration monitoring device and the backwash water heavy metal ion concentration monitoring device are electrically connected to the PLC, and the water inlet solenoid valve, the backwash drainage solenoid valve, and the three-way solenoid valve are electrically connected to the PLC. A communication module is provided in the PLC.

[0020] This embodiment also includes a control method for a heavy metal ion mineralization water purifier for water purification, which is used to control the above-mentioned heavy metal ion mineralization water purifier to perform purification. When the water purifier is in a normal water purification state, the water inlet solenoid valve is opened and the three-way solenoid valve is closed. The raw water enters the multi-layer filter column, the anion exchange column, the metal ion mineralization column and the water softening column in sequence through the water inlet pipe and comes out of the water purification pipe; when the purified water heavy metal ion concentration monitoring device on the water purification pipe detects that the heavy metal content in the purified water exceeds the standard, the water inlet solenoid valve is closed and the feedback is fed back to the customer's mobile phone app through the communication module. After the customer responds, the three-way solenoid valve and the backwash drain solenoid valve are opened, and the backwash agent A and / or B washes the materials inside through the multi-layer filter column, the anion exchange column, the metal ion mineralization column and the water softening column, and the wastewater after flushing flows directly into the sewer pipe; when the backwash water heavy metal ion concentration monitoring device at the sewer pipe detects that the ion concentration in the water reaches the drinking water standard, the water purifier is restored to a normal water purification state.

[0021] Design principle: The heavy metal ion mineralization water purifier organically combines water purification and automatic control. It monitors the water quality in the water inlet pipe and sewer pipe through the heavy metal ion concentration monitoring device. When the heavy metal ion concentration at the outlet of the purified water pipe is too high, the heavy metal ion concentration monitoring device sends a signal to the solenoid valve control cabinet, and the PLC controls the corresponding solenoid valve to open; when the heavy metal ion concentration at the sewer pipe meets the standard, the PLC controls the corresponding solenoid valve to close; at the same time, the heavy metal ion concentration monitoring device sends a signal to the mobile phone APP through the communication module.

[0022] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0023] 1. The heavy metal ion mineralization water purifier of the present invention can effectively purify water quality and can process heavy metal ions such as arsenic, copper, lead, zinc, and chromium. When the heavy metal ions such as arsenic, copper, lead, zinc, and chromium exceed the standard, the drinking water standard is reached after passing through the metal ion super-strong mineralization column. Moreover, the materials used inside this device are relatively cheap and the preparation cost is low. The material cost and use cost are far lower than the current drinking water purification process. Even if the subsequent water treatment still adopts the membrane process, the burden of the membrane can be greatly reduced and the service life of the membrane can be increased. The preparation of the heavy metal super-strong mineralization composite material is simple and easy to obtain, and it is a green and environmentally friendly adsorption material with excellent adsorption performance. It can achieve super-strong mineralization and efficient removal of heavy metal ions, and at the same time make up for the defects of the reverse osmosis membrane such as high price, short life, and large amount of wastewater. It has great application potential in the field of household water purifiers.

[0024] 2. The present invention includes a water purification system, a backwash system and a monitoring system. The device is simple to set up and can quickly and efficiently purify water.

[0025] 3. The process of treating water quality by the heavy metal ion mineralization water purifier device of the present invention is monitored and adjusted in real time, with low cost, thus meeting market demand. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic cross-sectional view of the heavy metal ion mineralization water purifier device of the present invention.

[0027] Figure 2 This is the XRD pattern of the arsenic adsorption material prepared in Example 1. It can be seen from the XRD pattern that the arsenic adsorption material has a bun peak at 15°~30°, and no obvious crystalline peaks are found at other positions, which indicates that the composite material is amorphous, that is, the iron oxyhydroxide formed on the silica gel ball exists in the form of an amorphous structure.

[0028] Figure 3 This is a SEM image of the arsenic adsorption material prepared in Example 1. As can be seen from the SEM image, the diameter of the arsenic adsorption material is in the range of 150 to 250 μm, and iron oxyhydroxide nanoparticles are dispersed and loaded on the surface.

[0029] Figure 4 This is the BET diagram of the arsenic adsorption material prepared in Example 1. By calculation, the specific surface area of ​​the arsenic adsorption material is 357m 2 / g.

[0030] Figure 5 This is the pore size distribution diagram of the arsenic adsorption material prepared in Example 1. According to calculation, the average pore size of the arsenic adsorption material is 9.456 nm, and the average pore volume is 0.931 cm 3 / g.

[0031] Figure 6This figure shows the arsenic removal rate of the arsenic adsorption material prepared in Example 1 as a function of time and dosage. As can be seen from the figure, when the dosage of the composite material is 5 g, the arsenic removal reaches an optimal state, and the adsorption equilibrium only takes 5 minutes, which is a relatively fast adsorption rate. The arsenic concentration in the treated arsenic-contaminated water is less than 0.01 mg / L.

[0032] Figure 7 This is a graph showing the arsenic removal rate of the arsenic adsorption material prepared in Example 1 as a function of pH. It can be seen from the graph that arsenic removal is not affected by the pH of the solution. Within the wide range of pH = 2 to 12, the arsenic removal rate can reach a minimum of about 99.5%. Under neutral conditions, the arsenic removal rate is close to 100%, meaning that the arsenic concentration in the treated arsenic-contaminated water is less than 0.01 mg / L.

[0033] Figure 8 This is a graph showing the arsenic removal rate of the arsenic adsorption material prepared in Example 1 as a function of temperature. It can be seen from the graph that the arsenic adsorption performance of the composite material of the present invention is not affected by temperature. At room temperature, the arsenic concentration in the treated arsenic-contaminated water is less than 0.01 mg / L.

[0034] In the attached figure, 1. multi-layer filter column, 2. anion exchange column, 3. metal ion mineralization column, 4. water softening column, 5. water inlet solenoid valve, 6. purified water heavy metal ion concentration monitoring device, 7. backwash drain solenoid valve, 8. backwash water heavy metal ion concentration monitoring device, 9. sewer pipe, 10. backwash system, 11. reagent A tube, 12. reagent B tube, 13. three-way solenoid valve. DETAILED DESCRIPTION

[0035] The following examples are intended to further illustrate the present invention, but are not intended to limit the scope of protection of the claims of the present invention.

[0036] The heavy metal ion mineralization water purifier device involved in the following embodiments is as follows Figure 1 As shown. The heavy metal ion mineralization water purifier consists of three parts: water purification system, backwash system and monitoring system.

[0037] The water purification system includes a multi-layer filter column 1, an anion exchange column 2, a heavy metal ion mineralization column 3, and a water softening column 4, which are sequentially connected in series from the water inlet to the purified water outlet. The heavy metal ion mineralization column 3 is filled between the inlet and outlet with a heavy metal adsorption material composed of amorphous iron oxyhydroxide nanoparticles supported on the surface of porous silica gel spheres. The diameter of the porous silica gel spheres is 150 to 250 μm, and the particle size of the amorphous iron oxyhydroxide nanoparticles is 10 to 50 nm. The ratio of the porous silica gel spheres to the amorphous iron oxyhydroxide nanoparticles is measured such that the molar mass ratio of silicon in the porous silica gel spheres to iron in the amorphous iron oxyhydroxide nanoparticles is 10 to 20:1.

[0038] In this embodiment, a water inlet solenoid valve 5 is provided on the water inlet pipe, and the water inlet solenoid valve 5 is a two-way valve.

[0039] The backwash system includes a reagent A tube 11 and a reagent B tube 12. The multilayer filter column 1, the anion exchange column 2, the heavy metal ion mineralization column 3 and the water softening column 4 are respectively provided with a backwash inlet pipe and a backwash outlet pipe. The outlet of the reagent B tube 12 and the outlet of the reagent A tube 11 are respectively connected to four three-way solenoid valves 13 and then respectively connected to the backwash inlets corresponding to the multilayer filter column 1, the anion exchange column 2, the heavy metal ion mineralization column 3 and the water softening column 4. The backwash outlet pipe is connected to the sewer pipe 9 through a backwash drainage solenoid valve 7. The backwash drainage solenoid valve 7 is a three-way valve. The backwash outlet pipes of the multilayer filter column 1, the anion exchange column 2, the heavy metal ion mineralization column 3 and the water softening column 4 are grouped into two and are respectively connected to the sewer pipe 9 through a three-way backwash drainage solenoid valve 7.

[0040] The monitoring system includes a PLC, a purified water heavy metal ion concentration monitoring device 6 and a backwash water heavy metal ion concentration monitoring device 8. The purified water heavy metal ion concentration monitoring device 6 is installed on the clean water pipe, and the backwash water heavy metal ion concentration monitoring device 8 is installed on the sewer pipe 9. The purified water heavy metal ion concentration monitoring device 6 and the backwash water heavy metal ion concentration monitoring device 8 are electrically connected to the PLC, and the water inlet solenoid valve 5, the backwash drainage solenoid valve 7, and the three-way solenoid valve 13 are electrically connected to the PLC. A communication module is provided in the PLC.

[0041] The present invention also includes a control method for a heavy metal ion mineralization water purifier for water purification, which is used to control the heavy metal ion mineralization water purifier to perform purification. When the water purifier is in a normal water purification state, the water inlet solenoid valve 5 is opened, the three-way solenoid valve 13 is closed, and the raw water enters the multi-layer filter column 1, the anion exchange column 2, the metal ion mineralization column 3 and the water softening column 4 in sequence through the water inlet pipe and comes out of the water purification pipe; when the purified water heavy metal ion concentration monitoring device 6 on the water purification pipe detects that the heavy metal content in the purified water exceeds the standard, the water inlet solenoid valve is closed. 5 is closed and fed back to the customer's mobile phone app through the communication module. After the customer responds, the three-way solenoid valve 13 and the backwash drain solenoid valve 7 are opened, and the backwash agent A and / or B washes the materials inside through the multi-layer filter column 1, the anion exchange column 2, the metal ion mineralization column 3 and the water softening column 4. The flushed wastewater flows directly into the sewer pipe 9; when the backwash water heavy metal ion concentration monitoring device 8 at the sewer pipe 9 detects that the ion concentration in the water reaches the drinking water standard, the water purifier is restored to the normal water purification state.

[0042] The following is a method for preparing a metal adsorption material. The method comprises adding porous silica gel balls to a divalent iron salt solution and adjusting the pH of the solution system to 2.8 to 3. Under stirring conditions, an oxidant is added dropwise to react. The reaction is stopped until no precipitate is generated in the solution system or the pH value remains stable. After standing for aging, the solid-liquid separation and drying are performed to obtain the material.

[0043] The porous silica gel balls of the present invention are commercial reagents and can be directly purchased from Yiming New Materials Co., Ltd. in Dongying, Shandong, China.

[0044] The key to the preparation method of the above-mentioned metal adsorption material lies in the use of porous silica gel spheres as a carrier material. The redox method is used to achieve the in-situ generation and growth of amorphous ferric oxyhydroxide on the surface of the porous silica gel spheres, resulting in a metal adsorption material composed of amorphous ferric oxyhydroxide nanoparticles loaded on the surface of the porous silica gel spheres. The inventors unexpectedly discovered that when using porous silica gel spheres as a carrier, the components in the porous silica gel spheres can effectively inhibit the formation of crystalline ferric oxyhydroxide, resulting in amorphous amorphous ferric oxyhydroxide, which has better heavy metal adsorption activity than crystalline ferric oxyhydroxide. This is unique.

[0045] As a preferred solution, the ferrous salt solution is obtained by dissolving a common ferrous salt in the art in water, and the common ferrous salt is at least one of ferrous sulfate, ferrous chloride, and ferrous nitrate.

[0046] As a preferred solution, the concentration of the divalent iron salt solution is 12 g / L to 20 g / L, preferably 14 to 16 g / L.

[0047] As a preferred embodiment, the stirring speed is 1000 rpm to 1500 rpm. If the stirring speed is too slow, it is difficult to float the silica gel balls, resulting in uneven loading of the ferric oxyhydroxide on the silica gel. If the stirring speed is too fast, the centrifugal force is too large, and most of the ferric oxyhydroxide does not have time to form on the silica gel balls, which also results in uneven loading of the ferric oxyhydroxide on the silica gel.

[0048] As a preferred solution, the oxidant is a common oxidant in the art that can oxidize divalent iron. The present invention selects green and environmentally friendly hydrogen peroxide as the oxidant, and the oxidant is hydrogen peroxide with a mass percentage concentration of 25-35%.

[0049] As a preferred solution, the aging time is 8 to 16 hours. By controlling the aging time, the iron oxyhydroxide can be controlled to grow into particles of appropriate particle size.

[0050] As a preferred solution, the adjustment solution system is achieved by using common dilute acid or dilute alkali, such as 5% sulfuric acid or 5% sodium hydroxide.

[0051] The preparation process of the metal adsorption material provided by the present invention is carried out at room temperature.

[0052] The specific preparation method of the metal adsorption material of the present invention comprises the following specific steps:

[0053] Step 1: Weigh a certain amount of divalent iron salt and dissolve it in a certain amount of deionized water. Stir the mixture magnetically (at a stirring rate of 1000 rpm to 1500 rpm) until the divalent iron salt is completely dissolved to obtain a divalent iron salt solution with a concentration of 10 g / L to 20 g / L.

[0054] Step 2: Weigh a certain amount of silica gel balls and place them into the divalent iron salt solution and continue stirring (stirring rate is 1000r / min~1500r / min), measure the pH value of the solution at this time, and adjust it to the range of 2.8~3;

[0055] Step 3: Evenly add a strong oxidant and continue stirring (stirring rate is 1000r / min~1500r / min). When no obvious precipitation appears in the solution or the pH value of the solution remains almost stable, stop adding the strong oxidant and stirring.

[0056] Step 4: Allow to stand for aging for 8 to 16 hours, filter with a sieve to obtain a solid product, and wash with deionized water several times until the pH value of the washing liquid reaches 7 to 8, dry in an oven at 60 to 70°C for 6 hours, and cool to finally obtain a composite material of silica gel balls loaded with amorphous iron oxyhydroxide.

[0057] The following is an example of heavy metal arsenic:

[0058] Example 1

[0059] Step 1: Weigh 15 g of ferrous sulfate heptahydrate and dissolve it in 1 L of deionized water. Stir magnetically until the ferrous sulfate heptahydrate is completely dissolved at a stirring rate of 1500 r / min to obtain a ferrous sulfate heptahydrate solution with a concentration of 15 g / L.

[0060] Step 2: Weigh 30 g of silica gel balls and place them into the ferrous sulfate heptahydrate solution while stirring at a rate of 1500 rpm. Measure the pH of the solution and adjust it to 2.8.

[0061] Step 3: Evenly add 30% hydrogen peroxide and continue stirring at a stirring rate of 1500 r / min. When no obvious precipitation appears in the solution or the pH value of the solution remains almost stable, stop adding hydrogen peroxide and stirring.

[0062] Step 4: Allow to stand and age for 12 hours, filter with a sieve to obtain a solid product, and wash with deionized water several times until the pH value of the washing liquid reaches 7-8, dry in an oven at 70°C for 6 hours, and cool to finally obtain a composite material of silica gel balls loaded with amorphous iron oxyhydroxide.

[0063] Example 2

[0064] Step 1: Weigh 15 g of ferrous sulfate heptahydrate and dissolve it in 1 L of deionized water. Stir magnetically until the ferrous sulfate heptahydrate is completely dissolved at a stirring rate of 1000 r / min to obtain a ferrous sulfate heptahydrate solution with a concentration of 15 g / L.

[0065] Step 2: Weigh 30 g of silica gel balls and place them into the ferrous sulfate heptahydrate solution while stirring at a rate of 1000 rpm. Measure the pH of the solution and adjust it to 3.

[0066] Step 3: Evenly add 30% hydrogen peroxide and continue stirring at a stirring rate of 1000 r / min. When no obvious precipitation appears in the solution or the pH value of the solution remains almost stable, stop adding hydrogen peroxide and stirring.

[0067] Step 4: Allow to stand for aging for 10 hours, filter with a sieve to obtain a solid product, and wash with deionized water several times until the pH value of the washing liquid reaches 7-8, dry in an oven at 60°C for 6 hours, and cool to finally obtain a composite material of silica gel balls loaded with amorphous iron oxyhydroxide.

[0068] Example 3

[0069] Step 1: Weigh 15 g of ferrous sulfate heptahydrate and dissolve it in 1 L of deionized water. Stir magnetically until the ferrous sulfate heptahydrate is completely dissolved at a stirring rate of 1250 r / min to obtain a ferrous sulfate heptahydrate solution with a concentration of 15 g / L.

[0070] Step 2: Weigh 30 g of silica gel balls and place them into the ferrous sulfate heptahydrate solution. Continue stirring at a stirring rate of 1250 r / min. Measure the pH value of the solution and adjust it to 2.9.

[0071] Step 3: Evenly add 30% hydrogen peroxide and continue stirring at a stirring rate of 1250 r / min. When no obvious precipitation appears in the solution or the pH value of the solution remains almost stable, stop adding hydrogen peroxide and stirring.

[0072] Step 4: Allow to stand and age for 8 hours, filter with a sieve to obtain a solid product, and wash with deionized water several times until the pH value of the washing liquid reaches 7-8, dry in an oven at 65°C for 6 hours, and cool to finally obtain a composite material of silica gel balls loaded with amorphous iron oxyhydroxide.

[0073] Comparative Example 1

[0074] Step 1: Weigh 10 g of ferrous sulfate heptahydrate and dissolve it in 1 L of deionized water. Stir magnetically until the ferrous sulfate heptahydrate is completely dissolved at a stirring rate of 1500 r / min to obtain a ferrous sulfate heptahydrate solution with a concentration of 10 g / L.

[0075] Step 2: Weigh 30 g of silica gel balls and place them into the ferrous sulfate heptahydrate solution, stirring at a rate of 1500 rpm. Measure the pH of the solution and adjust it to 2.8.

[0076] Step 3: Evenly add 30% hydrogen peroxide and continue stirring at a stirring rate of 1500 r / min. When no obvious precipitation appears in the solution or the pH value of the solution remains almost stable, stop adding hydrogen peroxide and stirring.

[0077] Step 4: Allow to stand and age for 12 hours, filter with a sieve to obtain a solid product, and wash with deionized water several times until the pH value of the washing liquid reaches 7-8, dry in an oven at 70°C for 6 hours, and cool to finally obtain a composite material of silica gel balls loaded with amorphous iron oxyhydroxide.

[0078] Comparative Example 2

[0079] Step 1: Weigh 15 g of ferrous sulfate heptahydrate and dissolve it in 1 L of deionized water. Stir magnetically until the ferrous sulfate heptahydrate is completely dissolved at a stirring rate of 900 r / min to obtain a ferrous sulfate heptahydrate solution with a concentration of 15 g / L.

[0080] Step 2: Weigh 30 g of silica gel balls and place them into the ferrous sulfate heptahydrate solution while stirring at a rate of 900 rpm. Measure the pH of the solution and adjust it to 2.8.

[0081] Step 3: Evenly add 30% hydrogen peroxide and continue stirring at a stirring rate of 900 r / min. When no obvious precipitation appears in the solution or the pH value of the solution remains almost stable, stop adding hydrogen peroxide and stirring;

[0082] Step 4: Allow to stand and age for 12 hours, filter with a sieve to obtain a solid product, and wash with deionized water several times until the pH value of the washing liquid reaches 7-8, dry in an oven at 70°C for 6 hours, and cool to finally obtain a composite material of silica gel balls loaded with amorphous iron oxyhydroxide.

[0083] Example 6

[0084] The adsorption material is the composite material prepared in Example 1. The treatment object is laboratory simulated arsenic contaminated water containing 2 mg / L of arsenic. Take 4 portions of 50 ml of laboratory simulated arsenic wastewater and pour them into 80 ml beakers. Add 1, 3, 5, and 7 g of the composite material of the present invention respectively. Stir magnetically at a constant speed of 160 r / min. At the contact time of 1, 3, 5, 7, and 10 minutes, take the upper liquid for filtration. The remaining arsenic content in the arsenic contaminated water during each contact time period is detected by ICP. The arsenic removal rate changes with contact time and material dosage as shown in Figure 2. Figure 5 It can be seen that the optimal dosage is 5g and the adsorption equilibrium time is 5min, which is a relatively fast adsorption rate. The arsenic concentration in the treated arsenic-contaminated water is less than 0.01mg / L.

[0085] Example 7

[0086] The adsorption material is the composite material prepared in Example 1. The treatment object is laboratory simulated arsenic wastewater with an arsenic content of 2 mg / L. 6 portions of 50 ml of laboratory simulated arsenic wastewater are poured into 80 ml beakers. The pH values ​​of the 6 portions of arsenic wastewater are adjusted to 2, 4, 6, 8, 10, and 12 in sequence with 5% sulfuric acid and 5% sodium hydroxide. 5 g of the composite material of the present invention is added to each beaker. After uniform magnetic stirring for 5 minutes, the upper layer is filtered and the remaining arsenic content in the arsenic-contaminated water under different solution pH conditions is detected by ICP. The arsenic removal rate changes with the solution pH value as shown in the figure. Figure 6 The arsenic removal rate is not affected by the pH value of the solution. Under neutral conditions, the arsenic removal rate can reach 99.5%. The arsenic concentration in the treated arsenic-contaminated water is less than 0.01 mg / L.

[0087] Example 8

[0088] The adsorption material is the composite material prepared in Example 1. The treatment object is laboratory simulated arsenic wastewater with an arsenic content of 2 mg / L. Five 50 ml portions of laboratory simulated arsenic wastewater are poured into 80 ml beakers. The temperature of the arsenic-contaminated water is adjusted to 25, 35, 45, 55, and 65 ° C in a constant temperature water bath. 5 g of the composite material of the present invention is added to each beaker. After uniform magnetic stirring for 5 minutes, the upper layer is filtered and the remaining arsenic content in the arsenic-contaminated water under different temperature environments is detected by ICP. The arsenic removal rate changes with the solution temperature as shown in Figure 2. Figure 7 The arsenic removal rate remains almost unchanged, and the arsenic concentration in the treated arsenic-contaminated water is less than 0.01 mg / L.

[0089] Example 9

[0090] The composite material prepared in Example 1 was used as the adsorbent material. The treatment target was laboratory simulated arsenic wastewater containing 2.05 mg / L of arsenic. 5 L of the simulated arsenic wastewater was pumped through a filter column (5 cm diameter, 10 cm length) filled with the composite material of the present invention using a peristaltic pump at a pumping rate of 100 mL / min. At filtration volumes of 1, 3, and 5 L, 5 mL of the filtrate was collected for ICP analysis. The arsenic concentration in each filtrate was 0 mg / L.

[0091] Example 10

[0092] The composite material prepared in Example 2 was used as the adsorption material. The treatment object was laboratory simulated arsenic wastewater containing 2.05 mg / L arsenic. Other operating parameters were the same as in Example 9. The final arsenic concentrations obtained were 0 mg / L, 0.004 mg / L, and 0.009 mg / L, respectively.

[0093] Example 11

[0094] The composite material prepared in Example 3 was used as the adsorption material. The treatment object was laboratory simulated arsenic wastewater containing 2.05 mg / L arsenic. Other operating parameters were the same as in Example 9. The final arsenic concentrations obtained were 0 mg / L, 0 mg / L, and 0.002 mg / L, respectively.

[0095] Comparative Example 1

[0096] In Comparative Example 9, the composite material prepared in Comparative Example 1 was used as the adsorption material. The treatment target was laboratory simulated arsenic wastewater containing 1.97 mg / L arsenic. Other operating parameters were the same as in Example 9. The final arsenic concentrations obtained were 0.009 mg / L, 0.018 mg / L, and 0.042 mg / L, respectively. The poor performance of Comparative Example 9 is due to the fact that, during the preparation of the composite material prepared in Comparative Example 1, the concentration of ferrous sulfate heptahydrate was low, and the silicon:iron molar mass ratio of the silica gel ball-supported ferric oxyhydroxide composite material did not reach 10-20:1. Consequently, the amount of ferric oxyhydroxide loaded on the silica gel balls was low, resulting in poor adsorption.

[0097] Comparative Example 2

[0098] In Comparative Example 9, the composite material prepared in Comparative Example 2 was used as the adsorption material. The treatment target was laboratory simulated arsenic wastewater containing 1.97 mg / L arsenic. Other operating parameters were the same as in Example 9. The final arsenic concentrations obtained were 0.043 mg / L, 0.058 mg / L, and 0.104 mg / L, respectively. The poor performance of Comparative Example 9 was attributed to the low rotational speed of only 900 rpm during the preparation of the composite material prepared in Comparative Example 2, which was insufficient to fully float the silica spheres, resulting in uneven distribution of the iron oxyhydroxide on the silica spheres.

[0099] The above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made using the invention, or direct or indirect applications in other related technical fields, should be included in the scope of protection of the present invention.

Claims

1. A heavy metal ion mineralization water purifier, characterized by: It includes a heavy metal ion mineralization column and a water purification system, wherein the water purification system includes a multi-layer filter column, an anion exchange column, a heavy metal ion mineralization column and a water softening column connected in series from the water inlet to the water purification outlet; The heavy metal ion mineralization column cavity is filled with a heavy metal adsorption material composed of amorphous ferric hydroxide nanoparticles loaded on the surface of porous silica gel balls between the water inlet and the water outlet. The heavy metal adsorption material is prepared by the following method: the porous silica gel balls are added to a divalent iron salt solution and the pH of the solution system is adjusted to 2.8-3. Under stirring conditions, an oxidant is added dropwise to react until no precipitate is generated in the solution system or the pH value remains stable, then the reaction is stopped. After standing for aging, the solid-liquid separation and drying are performed to obtain the heavy metal ion mineralization column. The stirring speed is 1000 r / min-1500 r / min. The diameter of the porous silica gel balls is 150-250 μm. The particle size of the amorphous ferric hydroxide nanoparticles is 10-50 nm. The ratio of the porous silica gel balls to the amorphous ferric hydroxide nanoparticles is measured based on a molar mass ratio of silicon in the porous silica gel balls to iron in the amorphous ferric hydroxide nanoparticles of 10-20:

1.

2. The heavy metal ion mineralization water purifier according to claim 1, characterized in that: A water inlet solenoid valve is provided on the water inlet pipe.

3. The heavy metal ion mineralization water purifier according to claim 2, characterized in that: The invention also comprises a backwashing system, which is connected with the multi-layer filter material column, the anion exchange column, the heavy metal ion mineralization column and the water softening column through pipelines for backwashing.

4. The heavy metal ion mineralization water purifier according to claim 3, characterized in that: The backwash system includes a reagent A tube and a reagent B tube. The multi-layer filter column, anion exchange column, heavy metal ion mineralization column and water softening column are respectively provided with a backwash inlet pipe and a backwash outlet pipe. The outlet of the reagent B tube and the outlet of the reagent A tube are respectively connected to four three-way solenoid valves and then respectively connected to the backwash inlet pipes corresponding to the multi-layer filter column, anion exchange column, heavy metal ion mineralization column and water softening column.

5. The heavy metal ion mineralization water purifier according to claim 4, characterized in that: The backwash outlet pipes of the multi-layer filter column, the anion exchange column, the heavy metal ion mineralization column and the water softening column are grouped into two and are respectively connected to the sewer pipe through a three-way backwash drainage electromagnetic valve.

6. The heavy metal ion mineralization water purifier according to claim 5, characterized in that: It also includes a monitoring system, which includes a PLC, a purified water heavy metal ion concentration monitoring device and a backwash water heavy metal ion concentration monitoring device. The purified water heavy metal ion concentration monitoring device is installed on the clean water pipe, and the backwash water heavy metal ion concentration monitoring device is installed on the sewer pipe. The purified water heavy metal ion concentration monitoring device and the backwash water heavy metal ion concentration monitoring device are electrically connected to the PLC, and the water inlet solenoid valve, the backwash drainage solenoid valve, and the three-way solenoid valve are electrically connected to the PLC. A communication module is provided in the PLC.

7. A method for controlling a heavy metal ion mineralization water purifier for water purification, for controlling the heavy metal ion mineralization water purifier according to claim 6, characterized in that: When the water purifier is in a normal water purification state, the water inlet solenoid valve is opened and the three-way solenoid valve is closed. The raw water enters the multi-layer filter column, anion exchange column, metal ion mineralization column and water softening column in sequence through the water inlet pipe and comes out of the water purification pipe; when the purified water heavy metal ion concentration monitoring device on the water purification pipe detects that the heavy metal content in the purified water exceeds the standard, the water inlet solenoid valve is closed and the feedback is sent to the customer's mobile phone app through the communication module. After the customer responds, the three-way solenoid valve and the backwash drain solenoid valve are opened, and the backwash agent A and / or B washes the materials inside the multi-layer filter column, anion exchange column, metal ion mineralization column and water softening column, and the wastewater after flushing flows directly into the sewer pipe; when the backwash water heavy metal ion concentration monitoring device at the sewer pipe detects that the ion concentration in the water reaches the drinking water standard, the water purifier is restored to a normal water purification state.

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