KR102477025B1 - Treatment system for side stream - Google Patents

Abstract

The present invention relates to a return flow treatment system capable of recovering and treating nutrients, in which water treatment efficiency can be improved by complementing each other to control the hydrogen ion concentration of return flow containing nutrients by filling in components lacking in each other through a treatment process unit and a recovery process unit. More specifically, the return flow treatment system comprises: a return flow measuring unit measuring the electrical conductivity and suspended solids of the return flow containing nutrients introduced through a sewage treatment process; a treatment process unit biologically treating at least one return flow classified from the sewage treatment process or the return flow measuring unit; a recovery process unit recovering the return flow measured in the return flow water measuring unit, chemically treating and supplying the same to the treatment process unit. In order to biologically treat the return flow, the recovery process unit supplies nutrient-treated water containing an alkaline solution to the treatment process unit, which is low in alkalinity, to control the hydrogen ion concentration.

Description

Reverse water treatment system capable of recovering and treating nutrients {Treatment system for side stream}

The present invention is a nutrient that can improve water treatment efficiency as it is possible to complement each other so that the hydrogen ion concentration of the return water containing nutrients can be adjusted by filling the parts of the ingredients that are lacking in each other through the treatment process unit and the recovery process unit. It relates to a wastewater treatment system capable of recovering and treating salts.

In general, proper treatment of backwater generated in sewage and sludge treatment processes is very important in terms of preventing environmental pollution.

This side stream contains high concentration of solids and nutrients depending on the characteristics. into the water, making proper treatment difficult.

In other words, if only the nutrient salts are treated, there is an insufficient aspect in terms of energy saving and resource recovery, and if the nutrient salts are only recovered, the treatment is not appropriate, which causes a burden in the sewage treatment process, resulting in a more stable and mutual Complementary systems are needed.

Turn-off water containing nutrients lacks alkalinity and an external carbon source, so a part to fill these parts is needed for biological treatment by microorganisms.

In the nutrient recovery process, it has a high hydrogen ion concentration (pH), which can play a role in supplementing the alkalinity of the biological treatment process.

Conventionally, since nitrogen, phosphorus, etc. cannot be sufficiently reduced only by the nutrient recovery process, the development of a biological treatment system by realistically supplementing these parts in the nutrient salt treatment process is urgently required.

Domestic Patent No. 10-1565647 (Announcement date: 2015.11.04.) Domestic Registered Utility No. 20-0331030 (Announcement date: 2003.10.22.) Domestic Patent No. 10-0643775 (Announcement date: 2006.11.10.) Domestic Patent No. 10-1938484 (Announcement date: 2019.01.14.)

In order to solve the above-mentioned problems of the prior art, the present invention can monitor the source of wake water through SS (Suspended Solid) and electrical conductivity. It can be estimated, and the purpose is to maintain optimization in the nutrient treatment and recovery process.

In order to solve the above-mentioned conventional problems, the discharge water treatment system capable of recovering and treating nutrients according to the present invention measures the electrical conductivity and suspended solids of the discharge water containing nutrients introduced through the sewage treatment process. A sewage treatment process or a processing unit for biologically treating at least one or more tailwater classified in the wakewater measurement unit and recovering the wakewater measured in the wakewater measurement unit, and chemically treating the Including a recovery process unit supplied to the treatment unit, wherein the recovery unit supplies nutrient salts treated water having an alkali liquid component to the treatment unit that has insufficient alkalinity in order to biologically treat the return water so that the hydrogen ion concentration is reduced. It is characterized by being regulated.

In addition, the treatment process unit is a primary treatment sedimentation tank for primary precipitation of the discharge water supplied from the sewage treatment process or the discharge water measurement unit to separate the sediment, the discharge water from which the sediment is separated and methanol supplied from the methanol input unit An anoxic tank to be mixed, an aerobic tank in which the run-off water supplied from the anoxic tank is accommodated and treating harmful substances in the run-off water using activated microorganisms, and a secondary treatment settling tank for separating the precipitate by secondary precipitation of the run-off water treated in the aerobic tank and a process sensor unit for measuring the hydrogen ion concentration of the counterflow water accommodated in at least one of the anoxic tank, the aerobic tank, and the secondary treatment settling tank.

In addition, the process sensor unit preferably includes an anoxic tank sensor for measuring the hydrogen ion concentration of the counterflow water accommodated in the anoxic tank, and an aerobic tank sensor for measuring the hydrogen ion concentration of the counterflow water accommodated in the aerobic tank.

In addition, the aerobic tank sensor includes a front sensor for measuring the hydrogen ion concentration of the counter flow water with respect to the front part of the aerobic tank and a rear sensor for measuring the hydrogen ion concentration of the counter flow water with respect to the rear part of the aerobic tank, the front sensor maintains the hydrogen ion concentration of the countercurrent at 7pH to 7.5pH, and the downstream sensor preferably maintains the hydrogen ion concentration at 6.3pH to 6.8pH.

In addition, the anoxic tank sensor preferably maintains the hydrogen ion concentration of the counterflow water accommodated in the anoxic tank at 6.5 pH to less than 7 pH.

In addition, the recovery process unit includes a primary recovery sedimentation battery for first precipitating the tail water supplied from the tail water measurement unit to separate sediments, and a caustic soda supply from the caustic soda input unit to the tail water supplied from the primary recovery sedimentation basin. A recovery and crystallization tank in which soda is mixed to adjust the hydrogen ion concentration, a recovery and crystallization tank in which the return water supplied from the recovery and adjustment tank and magnesium chloride supplied from the magnesium chloride inlet are mixed, and the return water mixed with magnesium chloride is mixed with the secondary water. Ammonia nitrogen and phosphate in the secondary recovery settling tank supplying the nutrient treated water from which the nutrient sludge is separated by precipitation to the treatment process unit and the return water contained in the secondary recovery settling tank are measured, and the hydrogen ion concentration is 10 pH It is preferable to include a concentration adjusting unit for controlling the input amount of caustic soda and magnesium chloride so that phosphorus nutrient treated water can be obtained.

In addition, the recovery process unit preferably further includes an adjustment tank sensor for measuring the hydrogen ion concentration of the return water accommodated in the recovery control tank.

According to the present invention, unlike the prior art, it is possible to monitor the source of wake water through suspended solids (SS) and electrical conductivity through the wake water measuring unit, and high-concentration or low-concentration nutrients can be detected through the sewage treatment process. When included turnover occurs, water treatment efficiency can be improved as mutual complementation is possible so that the hydrogen ion concentration can be adjusted by filling parts of each other's insufficient components through the treatment process unit and recovery process unit optimized for the corresponding return water. effect will be realized.

1 is a conceptual diagram of a return water treatment system capable of recovering and treating nutrient salts according to the present invention.

Hereinafter, various embodiments will be described in more detail with reference to the accompanying drawings. The embodiments described in this specification may be modified in various ways. Certain embodiments may be depicted in the drawings and described in detail in the detailed description. However, specific embodiments disclosed in the accompanying drawings are only intended to facilitate understanding of various embodiments. Therefore, the technical idea is not limited by the specific embodiments disclosed in the accompanying drawings, and it should be understood to include all equivalents or substitutes included in the spirit and technical scope of the invention.

Terms including ordinal numbers, such as first and second, may be used to describe various components, but these components are not limited by the above terms. The terminology described above is only used for the purpose of distinguishing one component from another.

In this specification, terms such as "comprise" or "having" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded. It is understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, but other elements may exist in the middle. It should be. On the other hand, when an element is referred to as “directly connected” or “directly connected” to another element, it should be understood that no other element exists in the middle.

In addition, in describing the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be abbreviated or omitted.

Hereinafter, with reference to the accompanying drawings, a return water treatment system capable of recovering and treating nutrient salts according to the present invention (hereinafter, simply referred to as a 'return water treatment system') will be described in detail. Prior to the description, the sewage treatment process 10 described below is a process of precipitating the inflow of wastewater multiple times, a process of treating harmful substances by reacting with microorganisms by an aerobic tank, and the like in a conventional wastewater treatment unit and wastewater. It refers to a process including a conventional sludge treatment unit that sequentially processes the separated sludge through concentration, digestion, dehydration, and drying processes, and detailed descriptions will be omitted so as not to flow the gist of the present invention.

First, as shown in FIG. 1, the wake water treatment system 1 according to the present invention largely consists of a structure including a wake water measuring unit 300, a treatment unit 100, and a recovery unit 200. Through the organic combination of these components, according to the hydrogen ion concentration of nutrients contained in the wash-off water, the corresponding wash-off water is returned to the treatment unit 100 through the treatment unit 100 or the recovery unit 200. It is intended to improve efficiency in the sewage treatment process by lowering the load of nitrogen and phosphorus contained in the return water by connecting a pipe (PIPE) to supply it.

More specifically, the return water measurement unit 300 measures the hydrogen ion concentration of the return water containing nutrients discharged from the sludge treatment unit, which is one of the sewage treatment processes 10, and will be described later according to the measurement result. It is a configuration for selectively inflowing the return water to the processing unit 100 or the recovery unit 200 to be performed.

To this end, as shown, the return water measurement unit 300 is independently pipe-connected to the wastewater treatment unit and the sludge processing unit on one side and the treatment unit 100 and the recovery unit 200 on the other side, thereby providing a sewage treatment process At least one of the flow rate, suspended solids (SS), and electrical conductivity of the low-concentration wake water for the wake water containing the nutrient salts introduced in (10) is measured, and the moving direction of the wake water is measured according to the measurement result. decide

For example, when the hydrogen ion concentration (pH) value of the return water measured by the return water measurement unit 300 is low concentration, it is guided toward the treatment unit 100, but when the hydrogen ion concentration value is high concentration, the recovery hole Directs towards the government (200).

In other words, before the digestion process in the sludge treatment unit, the electrical conductivity to the wake water is low, and after the digestion process, the electrical conductivity is high.

Here, high electrical conductivity means that there are many ionic materials, and in particular, it means that the concentration of ammonia nitrogen, phosphate, etc. is high.

In addition, if the solids recovery rate in the sludge treatment unit is not high, the suspended solids (SS: Suspended Solids) in the wake water rise. Based on the measured value of the suspended solids, the recovery rate of the sludge treatment unit is improved, To improve the pretreatment efficiency by considering the suspended solid matter of

At this time, if the electrical conductivity of the measured wake water is less than 1,000 uS/cm, the wake water measurement unit 300 classifies it as low concentration, and if it is more than that, it is classified as high concentration, and the wake flow is directed toward the processing unit 100 or the recovery unit 200. It is desirable to allow the inflow of water.

And, as shown in the figure, the processing unit 100 performs biological decomposition by microorganisms on the return water introduced from at least one of the above-described return water measurement unit 300 and the wastewater treatment unit to remove contaminants. As a configuration for processing, it includes a primary treatment sedimentation tank 110, an anoxic tank 120, an aerobic tank 130, a secondary treatment sedimentation tank 140, and a process sensor unit 20.

For example, the primary treatment settling tank 110 is a tank in which the inflowing stream water is accommodated and the sediment, which is one of the foreign substances contained in the received wake water, sinks primarily on the inner bottom surface of the primary treatment settling basin 110 and can be separated. (TANK) shape.

In addition, the precipitate separated by the primary treatment settling tank 110 has a structure that can be disposed of by being discharged to the outside by an open and close valve.

In addition, the anoxic tank 120 is a configuration for allowing methanol and the backflow water separated from the precipitate in the primary treatment settling tank 110 to be mixed with each other, and the anoxic tank 120 is also formed in the shape of a tank (TANK) .

Outside the anoxic tank 120, a methanol supply unit 150 for supplying methanol to be mixed with the counterflow water has a pipe-connected structure, and denitrification is caused through the supply of methanol to increase the hydrogen ion concentration of the counterflow water.

That is, in the anoxic tank 120 in the present invention, the reaction water whose hydrogen ion concentration has increased is introduced into the aerobic tank 130 in a state where the alkaline component is insufficient. (130) Nutrient-treated water, which is a high-concentration alkaline liquid, flows into the interior and mutually complements the process, creating an environment in which microorganisms can be activated, so that the treatment of nutrients (reducing the load of nitrogen and phosphorus) contained in the return water is possible. is to facilitate

At this time, outside the anoxic tank 120, an anoxic tank sensor 21, which is one of the process sensor units 20 for measuring the hydrogen ion concentration of the methanol-mixed wake water, is provided, and the anoxic tank sensor 21 is the anoxic tank It is preferable to use it for a purpose capable of maintaining the hydrogen ion concentration of the counterflow water received in (120) at 6.5 pH to less than 7 pH.

In addition, the aerobic tank 130 is a configuration in which the turn-off water supplied from the anoxic tank 120 is accommodated and harmful substances are treated in the turn-off water using activated microorganisms.

Unlike the prior art, the aerobic tank 130 in the present invention reacts with microorganisms in the front end and the aerobic tank 130 close to the outlet side of the anoxic tank 120 in contrast to the volume of the aerobic tank 130, so that the return water treated with water is It may be arbitrarily divided into a rear end close to the exit side where water is discharged.

In addition, as shown, the aerobic tank 130 may be provided with a pair of aerobic tank sensors 23 and 25 constituting the process sensor unit 20, and the pair of aerobic tank sensors 23 and 25 are A front-end sensor 23 measuring the hydrogen ion concentration of the counter-flow water present at the front end of the aerobic tank 130 and a rear-end sensor 25 measuring the hydrogen ion concentration of the counter-current water present at the rear end of the aerobic tank 130 includes

At this time, the front sensor 23 maintains the hydrogen ion concentration of the jetted water at 7pH to 7.5pH, and the rear sensor 25 is preferably used for a purpose capable of maintaining the hydrogen ion concentration at 6.3pH to 6.8pH.

In addition, the secondary treatment sedimentation basin 140 is a configuration for secondarily separating sediment from the backwater that has been biologically treated by microorganisms, and detailed description because it has the same structure as the primary treatment sedimentation basin 110 described above. should be omitted.

However, the secondary treatment settling tank 140 in the present invention may additionally have a structure for disposing of the precipitated sludge by discharging it to the outside through an open and close valve.

In addition, the recovery process unit 200 recovers the discharge water separated as high-concentration discharge water in the discharge water measurement unit 300, and then converts the alkali solution to the discharge water treated in the treatment process unit 100 having insufficient alkalinity. As a configuration for supplying, it includes a primary recovery sedimentation battery 210, a recovery adjustment tank 220, a recovery crystallization tank 230, a secondary recovery sedimentation battery 240 and a concentration adjustment unit 270, which are described below. Since the primary and secondary recovery sedimentation tanks 210 and 240 have the same tank structure as the primary and secondary treatment sedimentation tanks 110 and 140 described above, detailed descriptions are omitted so as not to obscure the gist of the present invention.

However, in the primary recovery settling cell 210, high-concentration turn-off water flows in through the turn-off measuring unit 300, and nutrient salts, which are high-concentration alkali liquid components, are discharged through the outlet side of the second recovery settling tank 240. Note that is a structure connected to the aerobic tank 130 and the pipe.

For example, the recovery adjustment tank 220 mixes the caustic soda supplied from the caustic soda input unit 250 with the counter-stream water supplied from the primary recovery settling tank 210 so that the hydrogen ion concentration of the counter-stream water can be adjusted.

To this end, an adjustment tank sensor 27 capable of measuring the hydrogen ion concentration of the return water accommodated therein is installed outside the recovery control tank 220 .

In addition, in the recovery crystallization tank 230, the return water supplied from the recovery adjustment tank 220 and the magnesium chloride supplied from the magnesium chloride input unit 260 are mixed, and the sludge is separated in the secondary recovery settling tank 240. Nutrients This is a configuration to make the hydrogen ion concentration of the treated water reach 10pH.

To this end, as shown, outside the secondary recovery settling tank 240, a concentration adjustment unit for measuring ammonia nitrogen and phosphate phosphorus for the received counter-flow water to determine whether nutrient treated water having a hydrogen ion concentration of 10 pH is obtained ( 270) is provided, and the concentration adjusting unit 270 individually controls the amounts of caustic soda injected into the recovery and crystallization tank 220 and magnesium chloride injected into the recovery and crystallization tank 230 to treat nutrient salts at a desired hydrogen ion concentration. number is obtained.

In other words, the nutrient salts treated water obtained through the recovery process unit 200 is a high-concentration alkaline liquid, but still has a high concentration of nitrogen and phosphorus, so additional treatment is required. Since the turnover water obtained by the method lacks alkalinity, it is necessary to supply an alkali solution.

Thus, the treatment process unit 100 and the recovery process unit 200 according to the present invention fill in parts of each other's insufficient components with respect to the obtained return water to help control the hydrogen ion concentration, thereby improving water treatment efficiency. can make it

Referring to the results of the batch test of nitrogen removal performance according to the hydrogen ion concentration adjustment through the configurations of the refuse water treatment system 1 according to the present invention described above, based on Table 1 below,

division no pH adjustment pH adjustment Non-ammonia nitrogen removal rate
(mg-N/g-MLSS/hr) 0.072 0.109

The non-ammonia nitrogen removal rates in the batch experiment for the wake water were 0.072 and 0.109 mg-N/g-MLSS/hr depending on whether or not the hydrogen ion concentration was adjusted.

Adjusting the hydrogen ion concentration was 1.5 times higher than the case of not adjusting, so the efficiency of adding an alkali agent was high.

In addition, looking at Table 2, which shows the pilot experiment of the counterflow bioreactor with methanol and caustic soda,

division Primary treatment water (mg/L) Removal efficiency (%) NH4-N TIN NH4-N TIN no input 160.2 164.6 54.3 18.4 Methanol 233 ppm 170.5 173.1 69.9 41.5 Methanol 214 ppm
Caustic soda 57ppm 151.9 152.6 89.4 72.3

After adding methanol to the anoxic tank 120, the removal efficiencies of ammonia nitrogen and total inorganic nitrogen (TIN) were improved by 15.6 %p and 23.1 %p, respectively.

In addition, when methanol and caustic soda were added at the same time, it improved by 19.5 %p and 30.8 %p compared to the case where only methanol was added.

Through this result, it can be seen that the introduction of methanol and caustic soda improves the nitrogen removal performance of the processing unit 100.

As described above, the wake water treatment system 1 according to the present invention differentiates the wake water generation source through the wake water measurement unit 300 through suspended solids (SS) and electrical conductivity. It can be monitored, and if return water containing high concentration or low concentration nutrient salts is generated through the sewage treatment process 10, the treatment process unit 100 and the recovery process unit 200 optimized for the return water are insufficient for each other. As the components are filled in parts and mutually complementary so that the hydrogen ion concentration can be adjusted, the effect of improving the water treatment efficiency is realized.

As described above, the present invention has been described by specific details such as specific components and limited embodiments and drawings, but these are provided to help a more general understanding of the present invention, and the present invention is not limited to the above embodiments. , Those skilled in the art in the field to which the present invention belongs can make various modifications and variations from these descriptions.

Therefore, the spirit of the present invention should not be limited to the described embodiments, and it will be said that not only the claims to be described later, but also all modifications equivalent or equivalent to these claims belong to the scope of the present invention. .

1: Reflux water treatment system capable of recovering and treating nutrients
100: processing unit
110: primary treatment sedimentation tank 120: anoxic tank
130: aerobic tank 140: secondary treatment settling tank
150: methanol supply unit
200: recovery process department
210: primary recovery sedimentation battery 220: recovery adjustment tank
230: recovery crystallization tank 240: secondary recovery settling tank
250: caustic soda supply unit 260; Magnesium Chloride Supply
270: concentration adjustment unit
10: sewage treatment process
20: process sensor unit

Claims (7)

A wake water measurement unit 300 for measuring electrical conductivity and particulate matter in wake water containing nutrients introduced through a sewage treatment process;
A sewage treatment process or a treatment process unit 100 that biologically treats at least one or more of the discharge water classified in the discharge water measuring unit 300; and
A recovery process unit (200) for recovering the wake water measured by the wake water measuring unit (300), chemically treating it, and supplying it to the processing unit (100);
The return water measuring unit 300,
If the electrical conductivity of the wake water is less than 1,000 uS/cm, it is classified as low concentration, and the wake water is introduced in the direction of the treatment unit 100, and if the electrical conductivity of the wake water is 1,000 uS/cm or more, it is classified as high concentration. So, the return water is introduced in the direction of the recovery process unit 200,
The processing unit 100,
A primary treatment sedimentation tank (110) for separating precipitates by primary precipitation of the reject water supplied from the sewage treatment process or the reject water measurement unit (300);
An anoxic tank (120) in which methanol supplied from the methanol input unit (150) is mixed with the return water from which the precipitate is separated;
an aerobic tank 130 that accommodates the turn-off water supplied from the anoxic tank 120 and treats harmful substances in the turn-off water using activated microorganisms;
A secondary treatment settling tank 140 for separating the precipitate by secondary precipitation of the backflow water treated in the aerobic tank 130; and
A process sensor unit 20 for measuring the hydrogen ion concentration of the counterflow water accommodated in at least one of the anoxic tank 120, the aerobic tank 130, and the secondary treatment settling tank 140;
The recovery process unit 200
a primary recovery settling tank 210 that separates precipitates by first precipitating the wake water supplied from the wake water measuring unit 300;
a recovery adjustment tank 220 for adjusting the hydrogen ion concentration by mixing the caustic soda supplied from the caustic soda input unit 250 with the counterflow water supplied from the primary recovery settling tank 210;
a recovery and crystallization tank 230 in which the return water supplied from the recovery adjustment tank 220 and the magnesium chloride supplied from the magnesium chloride input unit 260 are mixed;
A secondary recovery settling tank 240 for supplying nutrient treated water from which nutrient sludge is separated by secondary precipitation of countercurrent water mixed with magnesium chloride to the treatment unit 100; and
Concentration adjustment unit for controlling the input amount of caustic soda and magnesium chloride so that nutrient treated water having a hydrogen ion concentration of 10 pH can be obtained by measuring ammonia nitrogen and phosphate in the counterflow water accommodated in the secondary recovery settling tank 240 ( 270);
The secondary recovery sedimentation battery 240 of the recovery process unit 200 biologically treats the back water, and the alkalinity is insufficient in the aerobic tank 130 of the treatment process unit 100. Nutrients having an alkali liquid component An effluent treatment system capable of recovering and treating nutrients, characterized in that the hydrogen ion concentration is controlled by supplying treated water. delete According to claim 1,
The process sensor unit 20 is
an anoxic tank sensor 21 for measuring the hydrogen ion concentration of the wake water accommodated in the anoxic tank 120; and
An aerobic tank sensor (23, 25) for measuring the hydrogen ion concentration of the stream water accommodated in the aerobic tank (130); According to claim 3,
The aerobic tank sensors 23 and 25
a shear sensor 23 for measuring the hydrogen ion concentration of the counterflow water at the front end of the aerobic tank 130; and
A rear sensor 25 for measuring the hydrogen ion concentration of the counterflow water at the rear end of the aerobic tank 130; including,
The front sensor 23 maintains the hydrogen ion concentration of the counterflow water at 7pH ~ 7.5pH, and the rear sensor 25 maintains the hydrogen ion concentration at 6.3pH ~ 6.8pH Recovery of nutrients, characterized in that A waste water treatment system that can be treated. According to claim 3,
The anoxic sensor 21 is
The return water treatment system capable of recovering and treating nutrients, characterized in that the hydrogen ion concentration of the return water accommodated in the anoxic tank 120 is maintained at less than 6.5 pH to 7 pH. delete According to claim 1,
The recovery process unit 200
The return water treatment system capable of recovering and treating nutrient salts, characterized in that it further comprises; an adjustment tank sensor 27 for measuring the hydrogen ion concentration of the return water accommodated in the recovery control tank 220.

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