A new method of flocculation and device for purifying water

Abstract

The method comprises the following steps: (1) mixing a water purification agent precursor with liquid and performing excitation treatment, then adding the water purification agent precursor into water to be purified, or directly mixing the water purification agent precursor with the water to be purified and performing excitation treatment, so that the water purification agent precursor reacts to generate iron hydroxide and co-deposits with suspended matters and / or impurities in the water to be purified; the excitation treatment comprises adding an oxidizing substance; (2) performing solid-liquid separation on the mixture obtained in step (1), to obtain water after flocculation purification treatment; the method can settle suspended matters in water and adsorb part of organic impurities, and can avoid acid and salt caused by newly generated iron hydroxide; and the method further provides a flocculation water purification device.

Description

Technical Field

[0001] This invention belongs to the field of water purification technology, specifically relating to a novel method and apparatus for necessitating the formation of flocculation for water purification. Background Technology

[0002] Water is a vital resource for all life, including humans, and is the most important component of living organisms. Therefore, people are paying increasing attention to water management for the sake of health.

[0003] Existing water purification processes, such as tap water purification processes, typically include:

[0004] The first step involves generating aluminum hydroxide and / or ferric hydroxide and / or ferrous hydroxide colloids in the water to be treated through a chemical reaction method to settle suspended solids in the water and achieve solid-liquid separation.

[0005] The second step is to treat non-settled metal ions, organic matter, and nitrogen and phosphorus compounds.

[0006] The third step involves treating the water by adjusting its pH level and / or disinfecting it.

[0007] Since aluminum hydroxide, ferric hydroxide, and ferrous hydroxide are all insoluble in water, most of them cannot form colloids when directly added to water, making it difficult for them to form flocs and settle with suspended solids in the water, resulting in significant waste. Therefore, existing technologies typically use inexpensive but effective aluminum and / or iron salts in the first step of the chemical reaction, causing them to hydrolyze under corresponding pH conditions to generate the aforementioned hydroxide flocculants for sedimentation and water purification.

[0008] The hydrolysis chemical reaction principle of the aluminum salt and / or iron salt is shown in the following chemical reaction equations:

[0009] AlCl3 + 3H2O → Al(OH)3 + 3HCl;

[0010] FeCl3 + 3H2O → Fe(OH)3 + 3HCl;

[0011] 2FeCl2+5H2O+[O]→2Fe(OH)3+4HCl;

[0012] Al2(SO4)3+6H2O→2Al(OH)3+3H2SO4;

[0013] Fe2(SO4)3+6H2O→2Fe(OH)3+3H2SO4;

[0014] 2FeSO4+5H2O+[O]→2Fe(OH)3+2H2SO4.

[0015] As can be seen from the above chemical reaction formulas, the hydrolysis of aluminum and / or iron salts, while producing Al(OH)3 and / or Fe(OH)3 colloids, is inevitably accompanied by the generation of acids. These acids cause the chemical equilibrium system of the hydrolysis reaction to shift to the left, resulting in incomplete hydrolysis of aluminum and / or iron salts. Consequently, a small portion of aluminum and / or iron salts enters the next water treatment process and hydrolyzes into colloids that adhere to the equipment during the second step, affecting the water treatment effect of the second step. Furthermore, in the third step, the more alkaline oxidant added to the water for disinfection, the more salt is generated in the treated water. Therefore, after the existing water purification process, the acidity and salinity of the water are relatively high. Long-term consumption of drinking water purified by this process can disrupt the body's acid-base balance, significantly increasing the risk of cardiovascular disease, hypertension, and hyperlipidemia. Using this process for industrial wastewater reuse directly affects the quality of manufactured products.

[0016] To address the aforementioned shortcomings, existing technologies employ ion exchange resins and / or reverse osmosis processes to remove salinity and acidic compounds from water. However, due to the high selectivity of ion exchange resins and reverse osmosis membranes, the manufacturing of these processes is complex, resulting in high equipment management costs. Furthermore, the ion exchange resins and reverse osmosis membranes require frequent replacement during operation, with each replacement costing tens or even hundreds of thousands of yuan, leading to equally high operating costs. Therefore, ion exchange and reverse osmosis methods are difficult to widely adopt in production.

[0017] Currently, there is no perfect solution in existing technology that can both generate new hydroxides for flocculation and purify water without producing salt or acidic substances. Because it concerns public health and the environmentally friendly use of industrial water resources, it is necessary to optimize existing water treatment technologies. Summary of the Invention

[0018] The first objective of this invention is to provide a novel method for precipitating water through necrotic flocculation. This method can effectively settle suspended solids in water and adsorb some organic impurities, while avoiding the acid and salt produced by necrotic hydroxides, thus ensuring drinking health and reducing the adverse effects of water reuse in industry.

[0019] A second objective of this invention is to provide a flocculation water purification device suitable for the above-described method.

[0020] The first objective of this invention is achieved through the following technical solution:

[0021] One novel method for water purification through cellular flocculation includes the following steps:

[0022] (1) Mix the water purification agent precursor with the liquid and then add it to the water body to be purified after activating the water purification agent precursor to react and generate ferric hydroxide, which then co-sediments with the suspended solids and / or impurities in the water body to be purified.

[0023] The activation treatment includes the addition of an oxidizing substance;

[0024] (2) The mixture obtained in step (1) is subjected to solid-liquid separation to obtain water after flocculation and purification treatment.

[0025] A second novel method for water purification through cellular flocculation includes the following steps:

[0026] (1) The water purification agent precursor is directly mixed with the water to be purified and activated, so that the water purification agent precursor reacts to generate ferric hydroxide, and co-sediments with the suspended solids and / or impurities in the water to be purified.

[0027] The activation treatment includes the addition of an oxidizing substance;

[0028] (2) The mixture obtained in step (1) is subjected to solid-liquid separation to obtain water after flocculation and purification treatment.

[0029] The two methods described above can be carried out simultaneously. That is, while the water purification agent precursor is mixed with the liquid and activated, it is added to the water body to be purified, and the water purification agent precursor is directly mixed with the water body to be purified and activated.

[0030] The water purification agent precursor mentioned in step (1) is ferrous carbonate and / or ferrous hydroxide; the liquid is any one or a combination of more than one of the following: an aqueous solution of the water purification agent precursor, pure water, and the water body to be purified; preferably, pure water. When the liquid is a combination of more than one of the above components, there is no limitation on the proportion between the components.

[0031] When the liquid is water to be purified, the water purification agent precursor can be mixed with a small amount of water to be purified and activated before being added to a large amount of water to be purified, or the water purification agent precursor can be directly mixed with the water to be purified and activated.

[0032] This invention utilizes the aforementioned water purification agent precursor through activation treatment, i.e., oxidation reaction or the newly generated ferric hydroxide colloid from its reaction with hydrolysis, to settle suspended solids and / or impurities in water. The chemical reaction of the aforementioned water purification agent precursor is described in detail below:

[0033] When the water purification agent precursor containing ferrous iron undergoes activation treatment and comes into contact with oxidizing substances, the ferrous ions are oxidized to ferric ions. When the water purification agent precursor contains ferrous carbonate, since ferric carbonate is unstable in water, the ferrous carbonate will rapidly oxidize and hydrolyze in water to generate ferric hydroxide and release carbon dioxide during activation treatment and contact with oxidizing substances, as shown in Formula 1. When the water purification agent precursor is ferrous hydroxide, it reacts rapidly with oxidizing substances during activation treatment and is oxidized to ferric hydroxide, and no carbon dioxide is generated during the reaction, making it more environmentally friendly, as shown in Formula 2.

[0034] 4FeCO3 + 6H2O + 2[O] → 4Fe(OH)3 + 4CO2↑ (Equation 1)

[0035] 2Fe(OH)2+H2O+[O]→2Fe(OH)3 Formula 2.

[0036] As can be seen from the above chemical reaction equations, the method of the present invention can generate ferric hydroxide from the precursor of the water purification agent, creating a water purification process without the generation of byproducts such as acids or salts. It can achieve the effect of flocculation and water purification, avoid the negative impact of acids and salts on human health and water reuse in industry, and save the cost of treating byproducts.

[0037] Moreover, the activation treatment in step (1) of this invention includes the addition of oxidizing substances to generate ferric hydroxide, which utilizes the property of ferric ions to adsorb anions to adsorb organic matter, thereby achieving a better effect of reducing the COD value of the purified water.

[0038] The oxidizing substance mentioned in step (1) is one or a combination of one or more of oxygen, air, ozone, and hydrogen peroxide. When the oxidizing substance is a combination of one or more of the above components, there is no limitation on the proportion between the components.

[0039] Preferably, the oxidizing substance is oxygen and / or air.

[0040] As a further embodiment of the present invention, when the oxidizing substance mentioned in step (1) includes at least one gaseous oxidizing substance selected from oxygen, air, and ozone, the gaseous oxidizing substance is added to the liquid mixed with the water purification agent precursor by at least one of the following methods: jetting, spraying, aeration, and liquid spraying. Specifically, the liquid spraying method involves: spraying the liquid mixed with the water purification agent precursor upwards under pressure, allowing it to fall into the water body to be purified through an environment containing the gaseous oxidizing substance; or mixing the liquid mixed with the water purification agent precursor with at least one of the aforementioned oxidizing substances and spraying them together upwards under pressure, allowing them to fall into the water body to be purified through an environment containing the gaseous oxidizing substance. The process of the mixture falling from a height allows for sufficient contact with the gaseous oxidizing substance to achieve the oxidation reaction of the water purification agent precursor.

[0041] Preferably, when the oxidizing substance in step (1) includes air, the present invention introduces air in step (1) by aeration and / or liquid injection. More preferably, when the oxidizing substance in step (1) includes air, the present invention introduces air in step (1) by liquid injection, thereby facilitating contact between the liquid containing the water purification agent precursor and more air, and more rapidly activating the water purification agent precursor.

[0042] As a further embodiment of the present invention, the excitation treatment in step (1) is a combination of adding an oxidizing substance and heating and ultrasonic oscillation.

[0043] When the water purification agent precursor comes into contact with water or oxidizing substances and is heated or subjected to ultrasonic vibration, it will promote its hydrolysis reaction to generate hydroxides. In particular, ultrasonic waves generate cavitation bubbles in the liquid that can absorb sound wave energy and collapse and release energy in a very short time. When the cavitation bubbles collapse, they can generate high temperature and high pressure in a very small space around them, thereby promoting the hydrolysis and oxidation reactions of the water purification agent precursor.

[0044] When the water purification agent precursor contains ferrous carbonate, the ferrous carbonate may undergo the following hydrolysis reaction to generate ferrous hydroxide before it comes into contact with oxidizing substances under heating or ultrasonic vibration, see Formula 3.

[0045] FeCO3+H2O→Fe(OH)2+CO2↑ Equation 3.

[0046] The present invention can be improved as follows: in step (1), the amount of iron from ferrous carbonate, which is a precursor of water purification agent, is ≤300g per liter of water to be purified, and the amount of iron from ferrous hydroxide, which is a precursor of water purification agent, is ≤500g per liter of water to be purified.

[0047] Since iron ions in the solution exist in the form of hydrated ions, ferrous carbonate, as a precursor of water purification agents, absorbs a large amount of water when forming hydroxide. When the amount of iron from ferrous carbonate, a precursor of water purification agents, exceeds 300g per liter of water to be purified, it will absorb a large amount of water, resulting in a large volume of flocculated sludge, which increases the difficulty of solid-liquid separation and the treatment cost. When the amount of iron from ferrous hydroxide, a precursor of water purification agents, exceeds 500g per liter of water to be purified, the volume of flocculated sludge is large, and the treatment cost is also high.

[0048] The present invention can be improved as follows: in step (1), the iron element from the water purification agent precursor is ≥0.002g per liter of water to be purified.

[0049] Through multiple experiments, the inventors discovered that when the amount of iron from the water purification agent precursor in each liter of water to be purified is not less than 0.002g, it can effectively flocculate and settle suspended solids and / or impurities in the water to be purified.

[0050] The present invention can be improved as follows: In step (1), the pH value of the water to be purified is set to ≥2 to obtain a better flocculation effect. This is because when the pH value of the solution environment is less than 2, there will be obvious acid in the solution; at this time, a large part of the hydroxide generated by the water purification agent precursor will react with the acid to form soluble salt, reducing the amount of flocculent gel, thereby affecting the flocculation water purification effect.

[0051] The solution adopted by the present invention to achieve the second objective is as follows:

[0052] One of the novel flocculation water purification devices includes a flocculation sedimentation tank, characterized in that: an oxidizing substance addition device is added, the oxidizing substance addition device having at least one of a liquid oxidizing substance outlet, a gaseous oxidizing substance outlet, and a liquid outlet; the oxidizing substance addition device is connected to or located in the flocculation sedimentation tank, and is used to add oxidizing substances into the flocculation sedimentation tank.

[0053] A second novel flocculation water purification device includes a flocculation sedimentation tank, characterized in that: a water purification agent precursor activation tank is added and combined with the flocculation sedimentation tank;

[0054] The water purification agent precursor activation tank is used to activate the water purification agent precursor.

[0055] An oxidizing substance dosing device is provided in the water purification agent precursor activation tank, or an oxidizing substance dosing device is provided in both the water purification agent precursor activation tank and the flocculation sedimentation tank; the oxidizing substance dosing device is connected to or located in its corresponding water purification agent precursor activation tank and / or flocculation sedimentation tank, and is used to add oxidizing substances into the water purification agent precursor activation tank and / or flocculation sedimentation tank; the oxidizing substance dosing device is provided with at least one of a liquid oxidizing substance outlet, a gaseous oxidizing substance outlet, and a liquid outlet.

[0056] The outlet of the water purification agent precursor activation tank is connected to the flocculation sedimentation tank via a pipe, or the liquid flow is directed to the flocculation sedimentation tank via the outlet of the oxidizing substance dosing device installed in the water purification agent precursor activation tank.

[0057] The oxidizing agent dosing device can be a liquid oxidizing agent dosing device composed of a temporary storage tank and a pump, or a gas-liquid mixing device for mixing gaseous oxidizing agents with the water being purified. The gas-liquid mixing device can be at least one selected from a gas-liquid mixing jet device (Venturi tube), a liquid spray absorption tower, an aeration device, an aeration device, and a liquid jetting device.

[0058] The liquid oxidizing agent dosing device is equipped with a liquid oxidizing agent outlet; the aeration device in the gas-liquid mixing device is equipped with a gas oxidizing agent outlet; both the gas-liquid mixing jet device (Venturi tube) and the liquid spray absorption tower in the gas-liquid mixing device are equipped with liquid outlets; the aeration device in the gas-liquid mixing device is equipped with either a gas oxidizing agent outlet or a liquid outlet; and the liquid spraying device in the gas-liquid mixing device is equipped with a liquid outlet. The liquid flowing out of the liquid outlet is a liquid mixed with a water purification agent precursor and / or newly generated ferric hydroxide, or a mixture thereof with at least one of the aforementioned oxidizing agents. The aeration device is a combination of an air pump / compressed gas source and a connecting channel. The liquid spraying device consists of a pipe equipped with a pump and / or a compressed gas source and a nozzle, with the nozzle serving as the liquid outlet. It sprays the water to be purified into the environment containing the gas oxidizing agent through the combination of the pump and / or compressed gas source and the nozzle, allowing for a chemical reaction.

[0059] Furthermore, the flocculation sedimentation tank and / or the water purification agent precursor activation tank are also equipped with at least one of a heat exchange device and an ultrasonic generator.

[0060] The ultrasonic generator is either a fixed ultrasonic generator integrated with the flocculation sedimentation tank or the water purification agent precursor excitation tank, or a separate and movable ultrasonic generator independent of the flocculation sedimentation tank and / or the water purification agent precursor excitation tank.

[0061] The present invention can be improved as follows: a sedimentation tank is added to the bottom of the flocculation sedimentation tank, and the flocculation sedimentation tank has a discharge port at a position higher than the sedimentation tank. This arrangement allows the flocculated and purified water to be separated from the flocculated impurities through settling, allowing the purified water to flow out of the flocculation sedimentation tank, thus reducing the amount of impurities in the purified water. The sedimentation tank has an inverted conical structure, with a discharge port at its bottom.

[0062] The present invention can be improved as follows: a stirring device is added to the flocculation sedimentation tank and / or the water purification agent precursor activation tank to promote uniform mixing of the water purification agent precursor and / or the hydroxide converted therefrom with the water to be purified. Specifically, the stirring device is one or more of an impeller mechanical stirrer and a circulating liquid flow pump tube stirrer.

[0063] The present invention can be improved by adding a solid-liquid separation device, which is connected to the outlet of the flocculation sedimentation tank for solid-liquid separation of the mixture in the flocculation sedimentation tank. The solid-liquid separation device is selected from a filter press, a filter, a centrifuge, and an inclined tube sedimentation tank.

[0064] The present invention can be improved in the following way: a temporary storage tank is added, which is directly connected to the flocculation sedimentation tank and / or the water purification agent precursor activation tank and / or the solid-liquid separation device, or connected through a pump or solid feeder, for loading materials to be involved in water purification treatment, or temporarily storing materials from the water purification process and thereafter.

[0065] The present invention can be improved by installing a process data monitoring device in the flocculation sedimentation tank and / or the water purification agent precursor activation tank. The process data monitoring device includes at least one of a level gauge, hydrometer, viscometer, turbidity meter, pH meter, conductivity meter, redox potentiometer, flow meter, Tyndall effect detection device, and COD detector. Specifically, a viscometer and / or a Tyndall effect detection device are added to the flocculation sedimentation tank and / or the water purification agent precursor activation tank to monitor the formation of hydroxides online. The results obtained from the process data monitoring device ensure that the water purification agent precursor is effectively converted into hydroxides, achieving fuller utilization of the water purification agent precursor.

[0066] The present invention can be improved as follows: a process data detection device and an automatic detection and feeding controller are installed in the flocculation sedimentation tank and / or the water purification agent precursor activation tank. The automatic detection and feeding controller receives data from the process data detection device and automatically controls the operation of the entire flocculation water purification device based on the obtained data.

[0067] Compared with the prior art, the present invention has the following beneficial effects.

[0068] 1. This invention activates the precursor of the water purification agent, causing it to undergo oxidation and / or hydrolysis reactions to generate new hydroxide colloids for flocculation and water purification. This process does not produce byproducts such as acids or salts, thus avoiding the acids and salts caused by the newly generated hydroxides in existing water purification technologies. At the same time, it avoids or reduces the use of ion exchange resins and / or reverse osmosis equipment for neutralization and desalination, saving a large amount of expensive equipment investment and maintenance costs.

[0069] 2. This invention utilizes the hydrolysis and / or oxidation reactions of the water purification agent precursor to generate new hydroxide colloids for flocculation and water purification. In subsequent water purification processes, there is no need to purchase additional liquid alkali to neutralize the acid generated during the hydroxide generation process. There is also no need to frequently replace equipment accessories due to the adhesion of unhydrolyzed aluminum salts and / or iron salts to the equipment when they hydrolyze and form colloids in the impurity removal water treatment process. The process conversion will not increase production costs.

[0070] 3. This invention does not produce acids and salts due to hydrolysis during the process of generating new hydroxides, thus improving water quality, enhancing human health, and reducing the need for water reuse equipment in industry.

[0071] 4. The method of the present invention does not introduce new sources of pollution during the treatment process and has low water purification costs. Attached Figure Description

[0072] The invention will be further described below with reference to the accompanying drawings.

[0073] Figure 1 This refers to the flocculation water purification device used in Example 1;

[0074] Figure 2 This refers to the flocculation water purification device used in Example 2;

[0075] Figure 3 This refers to the flocculation water purification device used in Example 3;

[0076] Figure 4 This refers to the flocculation water purification device used in Example 4;

[0077] Figure 5 This refers to the flocculation water purification device used in Example 5;

[0078] Figure 6 This refers to the flocculation water purification device used in Example 6.

[0079] Figure reference numerals: 1-Flocculation sedimentation tank; 2-Water purification agent precursor activation tank; 3-Heat exchange device; 4-5-Ultrasonic generator; 6-8-Oxidizing substance addition device; 10-Sludge tank; 11-Stirring device; 14-Solid-liquid separation device; 15-17-Temporary storage tank; 19-23-Process data detection device; 24-Automatic detection and feeding controller; 25-28-Pump; 29-Compressed gas source; 40-41-Valve; 50-51-Discharge port; 55-Solid feeder; 56-57-Water purification agent precursor; 60-Water to be purified; 61-Purified water; 62-63-Oxidizing substance; 67-Flocculated sediment; 69-Solid sodium hydroxide; 70-Ozone generator; 71-Pure water. Detailed Implementation

[0080] The present invention will be further illustrated below through specific embodiments.

[0081] In the following embodiments, the flocculation sedimentation tank, water purification agent precursor activation tank, impeller mechanical agitator, and circulating liquid flow pump tube agitator used were all manufactured by Foshan Yegao Environmental Protection Equipment Manufacturing Co., Ltd., Guangdong Province; the ultrasonic generator was a commercially available product; ferrous hydroxide, ferrous carbonate, hydrogen peroxide, and oxygen were commercially available products; and the ozone generator, detection instrument device, and automated detection and feeding controller were commercially available products. Besides the examples above, those skilled in the art can also choose other products with similar performance to those listed above, based on conventional selection, to achieve the purpose of this invention.

[0082] Experiment on COD treatment effect in purified water

[0083] A standard organic solution with a COD value of 500 ppm was prepared using potassium hydrogen phthalate. After flocculation and sedimentation of 1 ton of water to be purified, the COD value of the resulting clear liquid was sampled and tested.

[0084] Validation test of flocculants in purified water

[0085] After co-precipitation of the hydroxide generated from the water purification agent precursor in 1 ton of water to be purified, the hydroxide generated from the water purification agent precursor is mixed with the water to be purified and co-precipitated. The purification effect is then detected by turbidity meter and / or by irradiation with a focused light source. Specifically, the results of the turbidity meter readings before and after are compared to determine the effect, or the bright path of the purified water is observed from the direction of perpendicular incident light. If the Tyndall effect is observed, it indicates the presence of colloids.

[0086] Example 1

[0087] like Figure 1As shown, this is the flocculation water purification device used in this embodiment, which includes a flocculation sedimentation tank 1; the flocculation sedimentation tank 1 is equipped with an oxidizing substance addition device 6; the oxidizing substance addition device 6 is a gas-liquid mixing device, specifically a gas-liquid mixing jet device, and its gas-liquid mixture outlet is located in the flocculation sedimentation tank 1.

[0088] In this embodiment, the oxidizing agent 62 is oxygen, and the water purification agent precursor 56 is a mixture of ferrous carbonate and ferrous hydroxide, which is added to the flocculation sedimentation tank 1 through the feeding port.

[0089] A novel method for water purification through cellular flocculation includes the following steps:

[0090] 1. For example Figure 1 Set up a flocculation water purification device and mix the water purification agent precursor with the water to be purified in the flocculation sedimentation tank 1 according to the amounts shown in Table 1.

[0091] 2. Start the oxidizing agent dosing device 6, use oxygen as the oxidizing agent to activate the water purification agent precursor in the flocculation sedimentation tank 1, cause the water purification agent precursor to react to generate ferric hydroxide, and co-sediment with suspended solids and / or impurities in the water to be purified, to obtain water after flocculation purification treatment.

[0092] In Example 1, the pH value of the water body 60 to be purified was 7, and the precursor used for the water purification agent was a mixture of ferrous carbonate and ferrous hydroxide. Testing revealed that the amount of ferric hydroxide (Fe3+) generated per cubic meter of water to be purified in this example was 100g, and no new acids or salts were found to be generated due to the water purification agent precursor. The water purification effect data of this example are listed in Table 1.

[0093] Example 2

[0094] like Figure 2 As shown, this is the flocculation water purification device used in this embodiment, which includes a flocculation sedimentation tank 1, a water purification agent precursor activation tank 2, ultrasonic generators 4 and 5, an oxidizing substance addition device 6, process data detection devices 19-23, an automatic detection and feeding controller 24, a temporary storage tank 15, a solid feeder 55, and an ozone generator 70.

[0095] The outlet of the water purification agent precursor activation tank 2 is connected to the flocculation sedimentation tank 1 through a pipe equipped with a pump 26, so that the liquid flow is directed into the flocculation sedimentation tank 1.

[0096] The flocculation sedimentation tank 1 is equipped with a mobile ultrasonic generator 4, process data detection devices 19 and 20 (specifically a pH meter and a level gauge), and a stirring device 11 (specifically a circulating liquid flow pump-type stirrer). It also includes an oxidizing agent dosing device 6; the oxidizing agent dosing device 6 is a bubbling aeration device connected to an ozone generator to add ozone to the flocculation sedimentation tank 1. A solid feeder 55 is installed in the flocculation sedimentation tank 1 to add solid sodium hydroxide to adjust the pH value of the purified water. A COD detector 23 is connected to the discharge port 51 at the bottom of the flocculation sedimentation tank 1 for sampling and inspection of the water. A sedimentation tank 10 is located at the bottom of the flocculation sedimentation tank 1, with a valve 40 and a discharge port 50 at its lowest point.

[0097] The water purification agent precursor excitation tank 2 is equipped with a fixed ultrasonic generator 5, process data detection devices 21 and 22 (specifically, an oxidation-reduction potentiometer and a viscometer) integrated with it.

[0098] In the water purification agent precursor activation tank 2, the mixture of water to be purified 60 and water purification agent precursor 56 is oxidized by activating the ultrasonic generator 5; the water purification agent precursor activation tank 2 is connected to an oxidizing substance dosing device composed of a temporary storage tank 15 and a pump 25.

[0099] The automatic feeding controller 24 controls the pump 25 to add oxidizing substances to the water purification agent precursor activation tank 2 and controls the start and stop of the ultrasonic generator 5 based on the results measured by the process data detection device 21 (oxidation-reduction potentiometer). Based on the results measured by the process data detection devices 22 (viscometer) and 20 (level gauge), the controller controls the pump 26 to add the mixture from the water purification agent precursor activation tank 2 to the flocculation sedimentation tank 1. Based on the results measured by the process data detection device 19 (pH meter), the controller controls the solid feeder 55 to add inorganic alkali to the flocculation sedimentation tank 1 to adjust the pH value of the liquid in the tank.

[0100] In this embodiment, the oxidizing substance 62 added to the temporary storage tank 15 is hydrogen peroxide, and the oxidizing substance 63 added to the flocculation sedimentation tank 1 is ozone; the water to be purified 60 is industrial acid-containing recycled water with a pH value of 0.2; and the water purification agent precursor 56 is ferrous carbonate.

[0101] A novel method for water purification through cellular flocculation includes the following steps:

[0102] 1. For example Figure 2 Set up a flocculation water purification device and mix the water purification agent precursor 56 with the water body 60 to be purified into the water purification agent precursor activation tank 2 according to the amounts shown in Table 1.

[0103] 2. Add oxidizing agent 62 to temporary storage tank 15, turn on pump 25, and start ultrasonic generator 5. Use hydrogen peroxide as the oxidizing agent in conjunction with the ultrasonic oscillator to stimulate the water purification agent precursor 56 in water purification agent precursor activation tank 2, causing it to react and generate hydroxide. When the data from the redox potentiometer and viscometer in water purification agent precursor activation tank 2 reach the set values, turn off pump 25, ultrasonic generator 5, and all feeding equipment.

[0104] 3. Based on the on-site detection data from process detection devices 21, 22, and 19, control pump 26 to feed the solution in the water purification agent precursor activation tank 2 into the flocculation sedimentation tank 1.

[0105] 4. Start the solid feeder 55 to add sodium hydroxide to the flocculation sedimentation tank 1 to adjust the pH value of the solution in the tank to 5, and at the same time start the ultrasonic generator 4, ozone generator 70 and oxidizing substance dosing device 6 to introduce ozone into the solution in the flocculation sedimentation tank 1; use ozone as an oxidizing substance to work with ultrasonic oscillation to further stimulate the unreacted water purification agent precursor and the generated ferrous hydroxide, so that the ferrous hydroxide generated by the complete reaction of the water purification agent precursor will co-sediment with the suspended solids and / or impurities in the water to be purified.

[0106] 5. Open valve 41 to divert the purified water 61 in flocculation sedimentation tank 1, and obtain the COD value by sampling and testing with a COD detector. Collect the sediment 67 in sedimentation tank 10 for further treatment.

[0107] In this embodiment, the pH value of the water body 60 to be purified is 0.2, and the water purification agent precursor 56 used is ferrous carbonate. The pH value of the purified water is 5. Testing revealed that the amount of ferric hydroxide (Fe3+) generated per cubic meter of water to be purified in this embodiment is 8g, and no new acids or salts were found to be generated due to the water purification agent precursor. The water purification effect data of this embodiment are listed in Table 1.

[0108] Example 3

[0109] like Figure 3 As shown, this is the flocculation water purification device used in this embodiment, which includes a flocculation sedimentation tank 1, a temporary storage tank 15, an oxidizing substance dosing device 6, a solid-liquid separation device 14, and an automatic detection and feeding controller 24.

[0110] The flocculation sedimentation tank 1 is equipped with a heat exchange device 3, an oxidizing agent addition device 6, a stirring device 11, and process data monitoring devices 20-22. The oxidizing agent addition device 6 is a gas-liquid mixing device, specifically a liquid spray absorption tower, using air as the oxidizing agent, and its gas-liquid mixture outlet is connected to the flocculation sedimentation tank 1. The stirring device 11 is an impeller mechanical agitator. The process data monitoring devices 20-22 are a Tyndall effect detection device, a conductivity meter, and a thermometer, respectively. A solid feeder 55 is installed and connected to the flocculation sedimentation tank 1 for adding the water purification agent precursor 56.

[0111] The temporary storage tank 15 contains water 60 to be purified and is connected to the flocculation sedimentation tank 1 through a pipe equipped with a process data detection device 19 (specifically a flow meter) and a pump 25.

[0112] The solid-liquid separation device 14 is a centrifuge, which is connected to the outlet of the flocculation sedimentation tank 1 via valve 40 and pump 27. The filtrate outlet of the centrifuge is connected to the temporary storage tank 16.

[0113] In this embodiment, the automatic feeding controller 24 controls the pump 25 to add water 60 to be purified into the flocculation sedimentation tank 1 according to the results measured by the process data detection device 19. The process data detection devices 20 and 21 detect the treatment status of the water 60 to be purified, and the process data detection device 22 controls the opening and closing of the heat exchange device 3 and adjusts the amount of heat exchange according to the results measured by the process data detection device 22.

[0114] The water purification agent precursor 56 used in this embodiment is ferrous hydroxide solid.

[0115] A novel method for water purification through cellular flocculation includes the following steps:

[0116] 1. For example Figure 3 Set up a flocculation water purification device and mix the water purification agent precursor 56 with the water body 60 to be purified in the flocculation sedimentation tank 1 according to the amounts shown in Table 1.

[0117] 2. Turn on the oxidizing agent dosing device 6 and the heat exchange device 3, and use air as an oxidizing agent to heat and activate the water purification agent precursor 56 in the flocculation sedimentation tank 1, so that the water purification agent precursor 56 reacts to generate ferric hydroxide and co-sedimentation with the suspended solids and / or impurities in the water body 60 to be purified.

[0118] 3. The mixture in the flocculation sedimentation tank 1 is separated into solid and liquid by a centrifuge in the solid-liquid separation device 14 to obtain water 61 after flocculation purification treatment, which is then temporarily stored in the temporary storage tank 16.

[0119] In this embodiment, the pH value of the water body 60 to be purified is 5, and the precursor of the water purification agent used is ferrous hydroxide. Testing revealed that the amount of ferric iron (Fe3+) generated per cubic meter of water body to be purified in this embodiment is 500g, and no new acids or salts were found to be generated due to the water purification agent precursor. The water purification effect data of this embodiment are listed in Table 1.

[0120] Example 4

[0121] like Figure 4 As shown, this is the flocculation water purification device used in this embodiment, which includes a flocculation sedimentation tank 1; the flocculation sedimentation tank 1 is equipped with an oxidizing substance dosing device 6, and process data detection devices 19 and 20; the oxidizing substance dosing device 6 is a gas-liquid mixing device, specifically a liquid spraying device, which sprays the water to be purified 60 into the air through a combination of a pump 27 and a nozzle (the nozzle is the liquid outlet) to react chemically with oxygen in the air, where the air refers to the environment containing oxidizing substances mentioned above; the process data detection devices 19 and 20 are a turbidity meter and a level gauge, respectively.

[0122] The flocculation sedimentation tank 1 is also connected to an oxidizing substance addition device composed of a temporary storage tank 16 and a pump 26. An oxidizing substance 62 (specifically hydrogen peroxide) is added to the flocculation sedimentation tank 1 to perform an auxiliary oxidation reaction on the water purification agent precursor 56. That is, the device of the present invention has two sets of oxidizing substance addition devices.

[0123] The flocculation sedimentation tank 1 is equipped with a solid feeder 55 for adding water purification agent precursor 56; it is also connected to a temporary storage tank 15 via a pump 25 to divert water to be purified 60.

[0124] The solid-liquid separator 14 is an inclined tube sedimentation tank, which is connected to the outlet of the flocculation sedimentation tank 1 via a pump 28; the outlet of the solid-liquid separator 14 is connected to a temporary storage tank 17 to store purified water 61.

[0125] The water purification agent precursor 56 used in this embodiment is ferrous carbonate solid.

[0126] A novel method for water purification through cellular flocculation includes the following steps:

[0127] 1. For example Figure 4 Set up a flocculation water purification device and mix the water purification agent precursor 56 with the water body 60 to be purified in the flocculation sedimentation tank 1 according to the amounts shown in Table 1.

[0128] 2. Turn on the oxidizing agent dosing device 6 and pump 26, and use air as the oxidizing agent and hydrogen peroxide to activate the water purification agent precursor 56 in the flocculation sedimentation tank 1, so that the water purification agent precursor 56 reacts to generate ferric hydroxide and release carbon dioxide, and the produced colloid co-sedimentes with the suspended solids and / or impurities in the water body 60 to be purified.

[0129] 3. The mixture in the flocculation sedimentation tank 1 is diverted to the solid-liquid separation device 14, and the water 61 after flocculation purification is obtained by the solid-liquid separation device 14 and temporarily stored in the temporary storage tank 17.

[0130] In this embodiment, the water body 60 to be purified is a water body containing suspended impurities with a pH value of 8. The water purification agent precursor used is ferrous carbonate, and the oxidizing substances are oxygen and hydrogen peroxide from the air. Testing revealed that the amount of ferric hydroxide (Fe3+) generated per cubic meter of water to be purified in this embodiment was 300g, and no new acids or salts were found to be generated due to the water purification agent precursor. The water purification effect data of this embodiment are listed in Table 1.

[0131] Example 5

[0132] like Figure 5 As shown, this is the flocculation water purification device used in this embodiment, which includes a flocculation sedimentation tank 1, an oxidizing substance dosing device 6, a liquid flow agitator 11, a solid-liquid separator 14, and temporary storage tanks 15 and 16.

[0133] The flocculation sedimentation tank 1 is equipped with an oxidizing substance dosing device 6 and process data detection devices 19 and 20. The oxidizing substance dosing device 6 is a gas-liquid mixing device, specifically a liquid spraying device. Through the combination of pump 26 and nozzle (the nozzle is the liquid outlet), the water to be purified 60 is sprayed into the air to react with oxygen in the air. The air mentioned here is the environment containing oxidizing substances mentioned above, so that the water purification agent precursor generates colloidal ferric hydroxide after the oxidation reaction. The process data detection devices 19 and 20 are a turbidity meter and a level meter, respectively.

[0134] The temporary storage tank 15 is used to prepare the water purification agent precursor 57 using pure water 71. It is equipped with a stirring device 11 (specifically a circulating liquid flow pump tube agitator) and a solid feeder 55 connected to it for adding the water purification agent precursor 56. The outlet of the temporary storage tank 15 is connected to the flocculation sedimentation tank 1 through the pump 25.

[0135] The solid-liquid separator 14 is an inclined tube sedimentation tank, which is connected to the outlet of the flocculation sedimentation tank 1 via a pump 27; the outlet of the solid-liquid separator 14 is connected to a temporary storage tank 16 to store purified water 61.

[0136] The water purification agent precursor 56 used in this embodiment is ferrous hydroxide solid.

[0137] A novel method for water purification through cellular flocculation includes the following steps:

[0138] 1. For example Figure 5A flocculation water purification device is set up, pure water 71 is added to the temporary storage tank 15, and ferrous hydroxide 56 is added to the solid feeder 55 to prepare the water purification agent precursor 57, namely ferrous hydroxide solution.

[0139] 2. Add the water body 60 to be purified to the flocculation sedimentation tank 1, and mix the water purification agent precursor 57 with the water body 60 to be purified in the flocculation sedimentation tank 1 according to the amount shown in Table 1.

[0140] 3. Turn on the oxidizing agent dosing device 6, and use air as the oxidizing agent to activate the water purification agent precursor 57 in the flocculation sedimentation tank 1, so that the water purification agent precursor 57 reacts to generate ferric hydroxide colloid, which co-sediments with the suspended solids and / or impurities in the water body 60 to be purified.

[0141] 4. The mixture in the flocculation sedimentation tank 1 is diverted to the solid-liquid separation device 14, and the water body 61 after flocculation purification is obtained by the solid-liquid separation device 14 and temporarily stored in the temporary storage tank 16.

[0142] In this embodiment, the water body 60 to be purified is a water body containing suspended impurities with a pH value of 6.9, and the water purification agent precursor used is ferrous hydroxide liquid. Testing revealed that the amount of ferric iron (Fe3+) generated per cubic meter of water to be purified in this embodiment was 0.002 g, and no new acids or salts were found to be generated due to the water purification agent precursor. The water purification effect data of this embodiment are listed in Table 1. This embodiment has simple equipment and operation, and no carbon dioxide or other impurities are generated during the process, making it suitable as a municipal tap water purification solution.

[0143] Example 6

[0144] like Figure 6 As shown, this is the flocculation water purification device used in this embodiment, which includes a flocculation sedimentation tank 1, a water purification agent precursor activation tank 2, an oxidizing substance addition device 6, an oxidizing substance addition device 7, an oxidizing substance addition device 8, a stirring device 11, and a solid-liquid separator 14.

[0145] The water purification agent precursor activation tank 2 is equipped with an oxidizing substance addition device 6 and a stirring device 11 (specifically a paddle stirring device). The oxidizing substance addition device 6 is a gas-liquid mixing device, specifically a liquid spraying device, which is equipped with a nozzle (i.e., a liquid outlet) facing the flocculation sedimentation tank 1. The mixture of water purification agent precursor 56 and pure water 71 is sprayed into the air through the combination of compressed gas source 29 and the nozzle to react with oxygen in the air to undergo an oxidation reaction. Here, the air refers to the environment containing oxidizing substances mentioned above, and the liquid flow is directed to the flocculation sedimentation tank 1. The compressed gas source 29 is specifically a high-pressure gas tank containing compressed air.

[0146] The flocculation sedimentation tank 1 is equipped with an oxidizing substance dosing device 7 and an oxidizing substance dosing device 8. The oxidizing substance dosing device 7 is a gas-liquid mixing device, specifically an aeration device, which has a gas oxidizing substance outlet to force air into the water body 60 to be purified. The oxidizing substance dosing device 8 is a gas-liquid mixing device, specifically an air pumping device, which consists of an air pump and a connecting channel to pump air into the water body 60 to be purified. The oxidizing substance dosing devices 7 and 8 cause the unreacted water purification agent precursor in the flocculation sedimentation tank 1 to react with oxygen in the air to generate colloidal ferric hydroxide.

[0147] The solid-liquid separator 14 is a filter press and is connected to the outlet of the flocculation sedimentation tank 1 via a pump 26.

[0148] The water purification agent precursor 56 used in this embodiment is ferrous carbonate solid.

[0149] A novel method for water purification through cellular flocculation includes the following steps:

[0150] 1. For example Figure 6 A flocculation water purification device is set up, and pure water 71 and water purification agent precursor ferrous carbonate 56 are added to the water purification agent precursor activation tank 2.

[0151] 2. Add 60g of the water to be purified to flocculation sedimentation tank 1;

[0152] 3. Add water purification agent precursor 56 to the water purification agent precursor activation tank 2 according to the amount shown in Table 1, turn on the oxidizing substance dosing device 6, use air as the oxidizing substance to activate the water purification agent precursor 56, and guide the liquid flow to the flocculation sedimentation tank 1; turn on the oxidizing substance dosing device 7 and oxidizing substance dosing device 8 to activate the unreacted water purification agent precursor 56 in the flocculation sedimentation tank 1; let the water purification agent precursor 56 react to generate ferric hydroxide colloid and co-sediment with the suspended solids and / or impurities in the water body 60 to be purified.

[0153] 4. The mixture in the flocculation sedimentation tank 1 is diverted to the solid-liquid separation device 14, and the water body 61 after flocculation purification is obtained by the solid-liquid separation device 14.

[0154] In this embodiment, the water body 60 to be purified is a water body containing suspended impurities with a pH value of 7, and the water purification agent precursor used is ferrous carbonate. Testing revealed that the amount of ferric hydroxide (Fe3+) generated per cubic meter of water to be purified in this embodiment was 50g, and no new acids or salts were found to be generated due to the water purification agent precursor. The water purification effect data of this embodiment are listed in Table 1.

[0155] Comparative Example 1

[0156] Using the flocculation water purification device of Example 1, and with the same water body to be purified as in Example 1, acidic ferric sulfate was added to the water body to be purified according to the amount of iron shown in Table 1; during the purification process, sodium hydroxide solution was added to adjust the pH value of the mixture to 7, so that all the iron ions in the mixture were hydrolyzed into ferric hydroxide and co-precipitated with impurities.

[0157] Tests revealed that the amount of ferric iron (Fe3+) generated per cubic meter of water to be purified in this comparative example was 100g. The sodium hydroxide solution added during the process reacted with the acidic ferric sulfate to generate sodium sulfate. The purification effect data for this comparative example are listed in Table 1.

[0158] Comparative Example 2

[0159] Using the apparatus for the water to be purified as described in Example 3, and with the same water as in Example 3, acidic ferric sulfate was added to the water according to the amount of iron shown in Table 1; sodium hydroxide was added during the purification process to adjust the pH of the water to be purified to 5.

[0160] Tests revealed that the amount of ferric iron (Fe3+) generated per cubic meter of water to be purified in this comparative example was 500g. Sodium hydroxide added during the process reacted with acidic ferric sulfate to generate sodium sulfate. The purification effect data for this comparative example are listed in Table 1.

[0161] Comparative Example 3

[0162] Using the apparatus for the water to be purified as described in Example 5, and with the same water as in Example 5, acidic ferric chloride was added to the water according to the amount of iron shown in Table 1; sodium hydroxide was added during the purification process to adjust the pH of the water to 6.9.

[0163] Tests revealed that the amount of ferric iron (Fe3+) generated per cubic meter of water to be purified in this comparative example was 0.002 g. Sodium hydroxide added during the process reacted with acidic ferric chloride to generate sodium chloride. The purification effect data for this comparative example are listed in Table 1.

[0164] Comparative Example 4

[0165] Using the apparatus of Example 2, the water to be treated with pH = 0.2 was treated according to the amounts shown in Table 1 and the method of Example 2. The difference from Example 2 is that inorganic alkali was no longer added to the flocculation sedimentation tank 1 to adjust the liquid pH.

[0166] The test results showed that the amount of ferric iron (Fe3+) generated per cubic meter of water to be purified in this comparative example was 0.001 g. The purification effect data of this comparative example are listed in Table 1.

[0167] Comparative Example 5

[0168] Using the apparatus of Example 5, the water body with pH = 6.9 was treated according to the amounts shown in Table 1 and the method of Example 5, and the water purification effect data are listed in Table 1.

[0169] The test results showed that the amount of ferric iron (Fe3+) generated per cubic meter of water to be purified in this comparative example was 0.001 g. The purification effect data of this comparative example are listed in Table 1.

[0170] Comparative Example 6 uses the apparatus for the water to be purified as in Example 6, and the water to be purified is the same as in Example 6. Ferrous carbonate, a water purification agent precursor, is added to the water to be purified according to the dosage shown in Table 1.

[0171] The test results showed that the amount of ferric hydroxide generated per cubic meter of water to be purified in this comparative example was 650g. The purification effect data of this comparative example are listed in Table 1.

[0172] Table 1

[0173]

[0174]

[0175] As shown in Table 1 above, in Examples 1 and 1, 3 and 2, and 5 and 3, the treatment effects on the water to be purified were similar when the amount of iron from the hydroxide was the same. New salts were generated in Comparative Examples 1-3, while the water purification agent precursor of the present invention did not introduce new anions present in the water. This proves that the process of the present invention can achieve the same effect as the prior art in flocculation purification treatment without generating acid and / or salt.

[0176] The difference between Example 2 and Comparative Example 4 is that the former adjusts the pH of the water to be treated in the tank to ≥2 by adding inorganic alkali solids to the flocculation sedimentation tank 1, while the latter does not adjust the pH of the water to be treated, which causes some iron hydroxide to be converted into iron salt, reducing the amount of iron hydroxide colloid and thus affecting the water treatment effect.

Claims

1. A method for purifying water through necessitating flocculation, characterized in that, Includes the following steps: (1) The water purification agent precursor is mixed with the liquid and activated, and then added to the water body to be purified. The water purification agent precursor reacts to generate ferric hydroxide, which co-sediments with the suspended solids and / or impurities in the water body to be purified. At the same time, the pH value of the water body to be purified is ≥2 to obtain a better flocculation effect. The water purification agent precursor is ferrous carbonate and / or ferrous hydroxide; such that each liter of water to be purified contains ≤300g of iron from ferrous carbonate as the water purification agent precursor and ≤500g of iron from ferrous hydroxide as the water purification agent precursor, and each liter of water to be purified contains ≥0.002g of iron from the water purification agent precursor. The activation treatment includes the addition of an oxidizing substance; (2) The mixture obtained in step (1) is subjected to solid-liquid separation to obtain water after flocculation and purification treatment.

2. A method for purifying water through cellular flocculation, characterized in that, Includes the following steps: (1) The water purification agent precursor is directly mixed with the water to be purified and activated, so that the water purification agent precursor reacts to generate ferric hydroxide, which co-sediments with the suspended solids and / or impurities in the water to be purified; at the same time, the pH value of the water to be purified is ≥2 to obtain a better flocculation effect. The water purification agent precursor is ferrous carbonate and / or ferrous hydroxide; such that each liter of water to be purified contains ≤300g of iron from ferrous carbonate as the water purification agent precursor and ≤500g of iron from ferrous hydroxide as the water purification agent precursor, and each liter of water to be purified contains ≥0.002g of iron from the water purification agent precursor. The activation treatment includes the addition of an oxidizing substance; (2) The mixture obtained in step (1) is subjected to solid-liquid separation to obtain water after flocculation and purification treatment.

3. The method for purifying water through necrotic flocculation according to claim 1, characterized in that, While adding the water purification agent precursor to the water body to be purified after mixing it with the liquid and performing an activation treatment, the water purification agent precursor is also directly mixed with the water body to be purified and subjected to an activation treatment.

4. The method for purifying water through necrotic flocculation according to claim 1, 2, or 3, characterized in that, The liquid is any one or a combination of more than one of the following: aqueous solution of water purification agent precursor, pure water, and water body to be purified.

5. The method for purifying water through necrotic flocculation according to claim 4, characterized in that, The oxidizing substance is one or more of oxygen, air, ozone, and hydrogen peroxide.

6. The method for purifying water through necrotic flocculation according to claim 5, characterized in that, When the oxidizing substance mentioned in step (1) includes at least one gaseous oxidizing substance selected from oxygen, air, and ozone, the gaseous oxidizing substance is added to the liquid containing the water purification agent precursor by at least one of the following methods: jetting, spraying, aeration, and liquid spraying. The liquid spraying method specifically involves: spraying a liquid containing a water purification agent precursor upwards under pressure, allowing it to fall into the water body to be purified through an environment containing gaseous oxidizing substances; or mixing a liquid containing a water purification agent precursor with at least one of the aforementioned oxidizing substances and spraying them together upwards under pressure, allowing them to fall into the water body to be purified through an environment containing gaseous oxidizing substances. The process of the mixture falling from a height allows it to fully contact the gaseous oxidizing substances, thereby achieving the oxidation reaction of the water purification agent precursor.

7. The method for purifying water through necrotic flocculation according to claim 6, characterized in that, The excitation treatment described in step (1) is a combination of adding an oxidizing substance and heating and ultrasonic oscillation.

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