KR100477170B1 - Effective Treatment System for Various Pollutants by using Two Bed Biofilter Process - Google Patents

Abstract

The present invention is the organic material present in the sewage, wastewater by varying the treatment conditions by the cross-pump and the solenoid valves that can connect the two biofiltration reactors up and down each other and smoothly control the flow of water in the center The present invention relates to a technique for effectively removing contaminants such as solids, nitrogen, and phosphorus simultaneously. At this time, the system of the present invention shows almost no clogging because the two biofiltration reactors are operated in an upflow, and the treatment conditions are changed to anaerobic and aerobic in one cycle and anaerobic and anaerobic in the next cycle, respectively. In the aerobic conditions, organic matter oxidation, solid filtration, nitrification and phosphorus intake reactions occur. In anaerobic conditions, organic matter decomposition, solid filtration, denitrification, and phosphorus release reactions occur to remove all organic matter, solids, nitrogen, and phosphorus present in the wastewater. Can be removed. In addition, in each of the reactors, aeration is alternately turned on and off. In one reactor, the operating conditions are continuously changed such as aerobic, anaerobic, aerobic, and anaerobic, so that the wastewater is treated. Therefore, the present invention is a treatment method that can effectively remove organic matter, solid matter, nitrogen and phosphorus present in water simultaneously.

Description

Effective Treatment System for Various Pollutants by using Two Bed Biofilter Process}

The present invention relates to a contaminant treatment system using a two-phase biofiltration reactor which is operated in an upflow by using two biofiltration reactors and a crossover pump which are cross-crossed, and more specifically, in two biofiltration reactors. Anaerobic and aerobic changes from one cycle to aerobic and anaerobic, respectively, depending on the residence time of the two cycles.The wastewater moves through the two reactors, causing organic matter oxidation, filtration, nitrification, denitrification, and dephosphorization. The present invention relates to a contaminant treatment system using a two-phase biofiltration reactor that can effectively treat various contaminants such as solids, nitrogen, and phosphorus simultaneously, and improves clogging and ensures smooth water movement, thereby improving operation efficiency.

Most of our country's water sources depend on surface water, with a very high 40% dependence on lake water. However, the nutritional status of these appealing waters is now mostly progressing from the mid-nutrition state to the nutrient-rich state, and if such conditions continue, it is expected that all the appealing waters will be inadequate for various water sources such as water sources at the end of this century. The main cause of eutrophication of these lakes is the presence of excess nitrogen and phosphorus.

To prevent nitrogen and phosphorus from causing eutrophication, the government has included nitrogen and phosphorus in effluent standards for sewage and wastewater treatment facilities since January 1, 1996 (total nitrogen less than 60 mg / L and total phosphorus less than 8 mg / L). However, this value is higher than the nitrogen and phosphorus concentrations in general municipal sewage in our country, indicating that this value is very unrealistic. However, in the case of advanced countries, the nitrous and phosphorus regulations of effluents are strict, which varies from state to state in the United States, but the average value is less than 3 mg / L and 0.5 mg / L, respectively. In Japan, the average value is 12 mg / L and 0.5 mg /, respectively. L or less

Therefore, if Korea is expected to strengthen its protection policy for limited water resources and globalize it in the future, the regulation of nitrogen and phosphorus will be strengthened in the future. However, the current sewage and wastewater treatment facilities are using the standard activated sludge process uniformly, and the removal efficiency of nitrogen and phosphorus is only 20-30% on average since this treatment is intended to remove organic matter and solids. There are several ways to treat nitrogen and phosphorus effectively. Chlorine injection, ammonia stripping, and selective ion exchange are effective physical and chemical methods to remove nitrogen, while flocculation and precipitation of phosphate forms using Lime, Alum, FeCl ₃ , and FeSO ₄ are effective chemical treatments. to be. However, these physical / chemical treatments have disadvantages of high processing cost and very high facility maintenance costs.

In addition, biological nitrogen and phosphorus simultaneous removal methods include A ² / O method, Bardenpho method, UCT method, VIP method, etc. All of the treatment principle is nitrification in anaerobic, anaerobic, aerobic state (ammonia by nitrification bacteria) Oxidative nitrogen is oxidized to nitrate nitrogen), denitrification (reduction of nitrate nitrogen to nitrogen gas by denitrification bacteria), Luxurious Uptake (microbial energy storage in aerobic conditions) Phosphorus accumulation) and phosphorus release (reaction of releasing phosphorus stored inside the microorganism in the anaerobic state to the outside) to treat nitrogen and phosphorus in the wastewater. However, all of these methods are suspended-growing microbial methods, which limits the amount of microorganisms in the reactor. In particular, the reactor modules that are basically operated are “anaerobic tank → anaerobic tank → anaerobic tank → anaerobic tank → aerobic tank → sedimentation tank”. There is a '1-4Q' internal transport from an aerobic tank to an anaerobic tank or an anaerobic tank to an anaerobic tank, so the volume of the whole process is very large and the operation method for the treatment is very complicated, requiring a highly skilled operation operation.

Therefore, to compensate for these drawbacks, it is possible to maintain high microbial volume per reactor cross-sectional area to increase the treatment efficiency, reduce the total volume by compacting the reactor, and simplify the reactor operation method to automatically operate nitrogen and phosphorus effectively without any skilled operation. There is a need for a process that can be handled.

Aerobic Aerated Filter process (hereinafter referred to as 'BAF process') was first developed by OTV in France in the early 1980s, and commercialized methods with various names such as Biopur, Biocarbon, and Biostyr have recently been used to effectively treat sewage and wastewater in Europe. It is a biofilm method that has been applied to the spotlight. ['The Biological Aerated Filter, A Promising Biological Process.', U.S. E.P.A., 832 / R831 / 02, Water Engrg. Res. Lab., Cincinnati, Ohlo. (1983)]

The BAF method is a new method in which a small particle medium is filled in a reactor, so that biodegradation of organic matter by adhesion microorganisms and filtration of suspended solids by the filling medium are performed in one reactor.

However, even in the BAF method, which has such advantages, denitrification and dephosphorization are not effective as the standard method. In the case of the simultaneous growth process of nitrogen and phosphorus removal, the wastewater and microorganisms are mixed with "anaerobic → anaerobic → aerobic → anaerobic → aerobic” The biofilm process is a state in which the microbial membrane itself is fixed.It moves to the flow of and changes the conditions from aerobic to anoxic or anaerobic to anaerobic by internal transport. This is not possible.

In addition, among the research results of treatment of wastewater and wastewater by the biofilm method, [Korea Patent Publication No. 94-0050620] installs ciliary media in a reactor and attaches microorganisms to treat wastewater and wastewater. It can only process ammonia nitrogen and does not remove total nitrogen or phosphorus. In addition, since there is no backwashing process, clogging or filling of microbial membranes may occur.

In addition, in the case of [Korea Patent Publication No .: 97-065437, 97-026942, 94-023807, 93-016354], it is possible to remove the clogging problem that is a problem in the biofilm method or to treat it in conjunction with activated sludge by post-treatment, thereby simply treating efficiency. It is not a method of effectively treating total nitrogen and total phosphorus by nitrification, denitrification and dephosphorization reaction in one system as the present invention.

Recently, in the case of [Korea Patent Registration No .: 10-0321562], a breakthrough technology for simultaneously removing organic matter, solids, nitrogen and phosphorus in wastewater and wastewater by using two cross-linked biofilm reactors has been announced. If there were a lot of solids in operation, water was frequently blocked or crossed with gravitational water heads, so smooth water transfer was not possible.

An object of the present invention is to improve the problems of the prior art described above, and the organic matter decomposition, physical filtration, nitrification in one reactor because the aeration and anaerobic conditions are repeated alternately by the injection position and the direction of the influent, the presence of the reactor aeration , Denitrification, and dephosphorization reactions all occur to remove organics, solids, nitrogen, and phosphorus, but only two biofiltration reactors cross each other up and down and run upstream without the addition of other methods. There is no risk of clogging even if there are many solids and there is a pump that crosses and transfers the water in the two reactors cross to provide an effective contaminant treatment system using a two-phase biofiltration reactor capable of smooth mixing and transfer of treated water.

It is an object of the present invention that the two reactors are reactors of the same capacity, and the upper and lower portions are crossed and connected to the first and the second connecting pipes, respectively, and alternately intersected by the first and second connecting pipes. The pump is installed to smoothly move the respective solenoid valves are installed on the first and second connecting pipe between each reactor and the pump,

The two reactors are provided with an inlet connected to an inflow inlet pipe into which the inflow is introduced at the lower end, an aeration device is disposed above the inlet, and a biofilm filling layer is installed on the aeration device.

One end of the first connecting tube is connected to the upper end of the one reactor so that the intermediate treated water is first treated in one reactor and the other end is inlet of the lower end of the other reactor to be introduced into the lower end to be processed in another reactor One end of the second connecting tube is connected to the upper end of the other reactor so that the first treated intermediate treated water from the other reactor flows out from the top, and the other end is introduced into the bottom to be finally treated in the one reactor. It is achieved by a contaminant treatment system using a two-phase biofiltration reactor according to the present invention having a structure connected to the inlet of the bottom of the.

The contaminant treatment system using the two-phase biofiltration reactor according to the present invention will be more clearly understood by its embodiments described in detail below with reference to the accompanying drawings.

The present invention is based on Lewis [Wat. Sci. Tech., Vol. 26, No. 3-4, pp 567 ~ 576 (1992)], based on the effect of "Phosphorus release in biofilm reactors", it is possible to remove phosphorus by changing the operating conditions even in fixed growth methods such as biofilm method. Based on the theory that two upflow biofilm reactors and cross-pumps are used, the conditions in the reactor are aerobic and anaerobic in stages according to the treatment time, and the flow of influent wastewater is variously adjusted for nitrification, denitrification, and dephosphorization. It is to let. At this time, the media formed by attaching the biofilm used a porous ceramic carrier.

   The system process diagram of the present invention is shown in FIG. 1, where the first reactor 1 and the second reactor 1 'are reactors of the same capacity, and the first and second connection pipes 2 and 2 are alternately disposed at the top and the bottom, respectively. ') Is cross-connected and connected to the middle of the first and second connecting pipes (2, 2') to smoothly move the pump (3) is installed and the first and second connecting pipes ( Solenoid valves (2a, 2b, 2'a, 2'b) are installed on 2 and 2 'to control the flow of water by opening and closing the solenoid valves, and the control of these solenoid valves is automatically controlled by the PLC. It was done.

The first reactor (1) and the second reactor (1 ') is provided with inlets (11, 11') for inflow water is introduced at the bottom and the inlet (4, 11) is provided in the inlet (11, 11 ') Connected and the solenoid valve (4a, 4b) is provided on the influent water inlet (4).

One end of the first connecting tube 2 is connected to the upper end of the first reactor 1 so that the intermediate treated water flows out of the first reactor 1 and the other end is connected to the second reactor 1 ′. It is connected to the inlet (11 ') of the lower end of the second reactor (1') to be introduced into the final treatment, one end of the second connecting pipe (2 ') is first treated in the second reactor (1') It is connected to the upper end of the second reactor (1 ') so that the intermediate treated water flows out, and the other end is connected to the inlet (11) of the lower end of the first reactor (1) so as to enter the final treatment in the first reactor (1) Since the treated water is always operated in an upflow, there is no fear of clogging no matter how many solids exist.

Above the inlet portions 11 and 11 'below the first reactor 1 and the second reactor 1', the aeration device 5 and the biofilm filling layers 12 and 12 'are provided.

The basic operating principle is that if one reactor is connected to and the second reactor 1 'is operated in an anaerobic state in which one reactor does not aeration, the other reactor is aerobic in aeration. If it is, the other reactors are operated in this way, alternating with the residence time in anaerobic state, and the inflow of raw wastewater is always introduced into the anaerobic reactor to obtain the final effluent from the aerobic reactor.

In addition, if the total treatment time is 12 hours, the first reactor 1 and the second reactor 1 'having the same residence time of 6 hours are each subjected to the combined treatment under anaerobic and aerobic conditions. After the second cycle, the first reactor (1) and the second reactor (1 ') are connected to each of the aerobic and anaerobic conditions, respectively. The cycle is operated.

If the total treatment time is 12 hours, the wastewater to be treated is first introduced into the inlet portion 11 of the lower portion of the first reactor 1, wherein the operating conditions of the first reactor 1 are in the anaerobic state without aeration. Organic matter decomposition, solid filtration, and phosphorus release occur as the biofilm filling layer 12 passes upward to remove organic matter and solids, and the phosphorus concentration is increased. Thus, the treated water is a solenoid valve (2'a, 2'b). Is closed and the solenoid valves 2a and 2b are moved to the lower part of the second reactor 1 'through the crossover pump 3, and then through the biofilm filling layer 12' of the second reactor 1 '. Is spilled to the top. At this time, the second reactor 1 'is aerated to perform organic matter oxidation, solid filtration, nitrification, phosphorus intake reaction in aerobic state, which removes organic matter, solids, ammonia nitrogen, and phosphorus, and increases nitrate nitrogen. Water is the final effluent 6A of the two-phase biofiltration reactor.

However, the concentration of nitrate nitrogen is not high in the treated effluent. This is because the first reactor (1), which is the anaerobic condition, was operated in aerobic condition for 6 hours before one cycle. Since the treated water is operated in the anaerobic condition for 6 hours while the inflowed water is present in the first reactor 1, the nitrate nitrogen generated in the aerobic condition is reduced to nitrogen gas by denitrification. The aerobic second reactor (1 ') was also operated in anaerobic conditions for 6 hours before one cycle, so the initial inlet portion would have moved to the next aerobic reactor, but the subsequent influent treated water was present in the second reactor (1'). In this condition, the processing conditions are changed to aerobic and operated for 6 hours. Therefore, the excess phosphorus released under anaerobic conditions passes through intake reaction. Sea phosphorus concentrations will decrease.

As a result, the reaction paths of '→ (first reactor) → (second reactor) →', '← (first reactor) ← (second reactor) ←' always produce anaerobic reactions after anaerobic reactions. However, in one reactor of each of the first reactor (1) and the second reactor (1 '), its own operating conditions change from' anaerobic to aerobic to anaerobic to aerobic 'every time the cycle is changed. Can also be effectively treated.

After that, in the same cycle as above, the solenoid valves 2a and 2b are closed after the second reactor 1 'is treated anaerobicly, starting with the inflow of the wastewater from the inlet 11' of the second reactor 1 '. With the solenoid valves 2'a and 2'b open, the pump 3 moves to the bottom of the first reactor 1 and is treated in the aerobic first reactor 1 so that the final effluent 6B is from the top. To be discharged. In this way, each of the reactors in parallel with the anaerobic and aerobic treatment conditions continuously alternately to obtain a perfect nitrogen, phosphorus removal effect.

The backwashing process is carried out once every 23 minutes and 50 minutes after the reactor operation, and the remaining 10 minutes. First, the excess microorganisms are removed by performing the backwashing aeration for 4 minutes using an acid pipe with the aeration apparatus 5. Afterwards, 3 minutes of washing with excess microorganisms by backwash water pump (7) with backwashing aeration moves all desorption microorganisms and debris to the top of the packed bed. The filth 8 naturally discharges the upper dirts out.

<Example>

   The following shows the results of treatment of each item according to the reactor residence time in order to explain in detail the actual treatment result and its efficiency.

As a result of treatment using the ideal biofiltration method of the present invention for K wastewater, which is discharged together with domestic sewage and about 10% of plant equipment wastewater, the characteristics of the raw wastewater are CODcr 192 ppm, BOD ₅ 129 ppm and 114 ppm of solids (SS), 52 ppm of total nitrogen, and 12.0 ppm of total phosphorus, but even 8 hours of treatment resulted in CODcr 28.1 ppm, BOD ₅ 7.6 ppm, SS 5.9 ppm, total nitrogen of 2.38 ppm, total phosphorus 2.55 ppm of high organic matter, solids, nitrogen and phosphorus removal rate, clear and clean treatment water was obtained, and this was obtained by CODcr 34.2 ppm, BOD ₅ 14.4 ppm, SS 6.8 ppm, total nitrogen 3.02 ppm, A solid result of 3.32 ppm total was obtained. At this time, the blockage phenomenon in the reactor did not appear at all for 120 days, and smooth water transfer by the cross pump was also confirmed.

On the other hand, after measuring the dissolved oxygen after changing the conditions of the reactor from aerobic to anaerobic, the concentration of 3.0 to 4.0 ppm in the aerobic state was from 1 hour 53 minutes after the aeration stop for 6 hours and from 4 hours From 1 hour 18 minutes, from 2 minutes to 56 minutes, from 1 minute to 41 minutes from 1 hour of residence time, the concentration of aerobic and anaerobic conditions in the reactor with or without aeration in one reactor, I could confirm it.

table. Treatment result of K sewage and wastewater by two-phase biofiltration treatment system

The pollutant treatment system using the two-phase biofiltration reactor according to the present invention is provided with a pump and solenoid valves capable of connecting two reactors with each other in an up and down cross and smoothly controlling the flow of intermediate treatment water at an intersection point. As the two reactors are operated in an upflow, there is almost no clogging, and the forced transfer of intermediate treatment water is possible, which greatly improves the treatment capacity and changes the treatment conditions according to the reactor residence time. In the cycle, the process is carried out by changing the conditions to aerobic and anaerobic, respectively.In aerobic conditions, organic matter oxidation, solid filtration, nitrification, and phosphorus intake reactions occur. Can remove all the organics, solids, nitrogen and phosphorus .

1 is a process diagram showing a system for effectively treating various contaminants such as organic matter, solids, nitrogen, phosphorus, etc. in wastewater using two biofiltration reactors as an embodiment according to the present invention.

Claims (1)

If two reactors having the same volume and residence time are connected to each other by connecting pipes to cross each other's top and bottom, and if one reactor is anaerobic without aeration, the other reactor is aerobic with aeration. In the contaminant treatment system using a two-phase biofiltration reactor operating alternately depending on the residence time if the other reactor in the anaerobic state, The two reactors are reactors of the same capacity, and the upper and lower portions are alternately connected to each other by the first and second connection pipes, respectively, and smoothly move water to the intersections of the first and second connection pipes. A pump is installed and a solenoid valve is installed on the first and second connection pipes between each reactor and the pump, The two reactors are provided with an inlet connected to the influent inlet pipe into which the inflow is introduced, the aeration device is disposed above the inlet, and the biofilm filling layer is installed above the aeration device. One end of the first connecting tube is connected to the upper end of the one reactor so that the intermediate treated water is first treated in one reactor and the other end is inlet of the lower end of the other reactor to be introduced into the lower end to be processed in another reactor One end of the second connecting tube is connected to the upper end of the other reactor so that the first treated intermediate treated water from the other reactor flows out from the top, and the other end is introduced into the bottom to be finally treated in the one reactor. Pollutant treatment system using a two-phase biofiltration reactor, characterized in that connected to the inlet of the bottom.