KR100917267B1 - Graywater recycling apparatus using rainfall - Google Patents

Abstract

A reuse water supply system using rainwater effluent is provided to process nonpoint polluted materials efficiently of the rainwater effluent, and to prevent river contamination. A reuse water supply system using rainwater effluent includes an initial rainwater processing part(A), a biological processor(B), and a reuse water supply part(C). The reuse water supply part stores processed water of the biological processor. The initial rainwater processing part comprises an initial rainwater reservoir(10), a rapid mixing tank, a mixing tank with low speed, a chemical storage tank(13) and a settling tank(14). The biological processor is comprised of a biological filtration phase(20) and a water treatment tank. The biological filtration phase comprises includes a biological activated carbon layer, granule sulfur, a limestone filled layer, a sand layer, and a gravel layer. The reuse water supply part includes a reuse water reservoir(30).

Description

Gray water recycling apparatus using rainfall

In order to overcome the hydraulic instability of non-point pollutant treatment, the present invention includes an initial excellent treatment unit having a reservoir for storing an initial excellent water containing a large amount of non-point pollutant and physically and chemically treating the initial excellent, and an initial excellent. It is possible to efficiently treat non-point pollutants in rainfall runoff by storing excess water inflow exceeding the treatment water and the design flow rate of the treatment part in the final reuse water reservoir through the biological treatment part. The present invention relates to a reusable water supply system using rainfall runoff.

In general, non-point pollution sources, unlike point pollution sources where pollutants such as household sewage and industrial wastewater are generated from specific pollutants, are mainly polluted with rainwater runoff when it rains. Non-point pollutants emitted from these non-specific pollutants contain various pollutants such as dust and rubbish in urban areas or air pollutants dropped on the ground.

Contaminant content for non-point pollution sources is estimated in Korea's Apartment, Detached Houses, Commercial, Industrial and Road Areas, as outlined in the Korea Environmental Policy Institute's Measures for Reducing Rainwater Runoff (2002). As shown in [Table 1], the average concentration of pollutants in the total amount of suspended solids (SS) in nonpoint pollutants was high in all regions, and compared to COD, It can be seen that the concentration of TN) is relatively high.

division COD (mg / L) SS (mg / L) TN (mg / L) TP (mg / L) Apartment area 15.9 59.6 3.26 0.31 Detached House Area 38.5 32.5 5.00 0.24 Commercial area 57.8 52.5 9.62 0.39 Industrial area 61.3 67.6 7.35 0.40 Road area 67.6 126.00 7.56 0.48

In general, TN is removed through biological nitrification and denitrification, and the concentration of organic matter required for stable TN removal is known to be when the ratio of COD / N is 3.0 to 6.0. However, since the initial rainfall effluent lacks COD as an easily biodegradable organic material, it is necessary to supply an external carbon source such as methanol for denitrification. However, in the case of injecting organic substances such as methanol to remove TN in non-point pollutants, there is a risk of causing another pollution if the proper amount is not injected due to the increase of COD in the treated water quality.

Therefore, autotrophic denitrification using sulfur has been studied (Batchelor and Lawrence, 1978; Claus and Kutzner, 1985; Koenig and Liu, 1996; Zhang and Lampe, 1999; Oh et al. , 2001). The most important part of autotrophic denitrification with sulfur is the supply of electron donors for autotrophic denitrification and maintenance of optimal pH through adequate alkalinity supplementation. This is because, unlike heterotrophic denitrification, various sulfur compounds are used as electron donors in autotrophic denitrification, and thus H ⁺ ions are generated as reaction products, resulting in a decrease in pH.

In general, patents related to autotrophic denitrification, which is a mechanism used for nitrogen removal, are described as a method for removing nitrogen from wastewater by performing a denitrification process using sulfur particles to remove high concentration nitrogen of Korean Patent No. 10-0336483. , Removal of nitrogen by causing livestock wastewater and wastewater containing high concentrations of nitrogen in Korea Patent Registration No. 10-0362742 to heterotrophic denitrification by organic matter contained in raw water and autotrophic denitrification in biofilters using sulfur particles And a biological nitrogen removal device installed in a reaction tank with a granular state filled with granular state of Republic of Korea Patent No. 10-0466934, which induces nitrification outside the fiber network and uses sulfur inside the fiber network. Induces autotrophic denitrification and simultaneously nitrification and denitrification in a single reactor Method of performing, on-site, off-site treatment and riverside filtration of the groundwater using the sulfated autotrophic microorganism of the Republic of Korea Patent No. 10-0431394, and sulfur-filled MBR reactor of Republic of Korea Patent No. 10-0547463 Those relating to nitrogen removal devices are known.

In addition, a variety of techniques and methods for removing non-point contaminants have been developed, the non-point source removal device of the Republic of Korea Patent No. 10-443420, the first non-point pollutant treatment device of the Republic of Korea Patent No. 10-491867, Republic of Korea registered Although various patents have been registered, such as an apparatus for purifying non-point contaminants of the initial effluent water of Patent No. 10-561092, and other various technologies have been applied for and disclosed, in the case of the above patents, the outflow flow rate is due to the characteristics of the non-point source caused by rainfall. Since it is not constant, problems arise in terms of the hydraulic stability required for physical and chemical treatments, and there is a limit to the operation of stable treatment facilities.

The treated water treated by the expensive non-point pollutant removal device is treated with non-point pollutants by discharging it to the stream without recycling the treated water, although the water quality is better than that of the general sewage treatment process. We act as obstacle of introduction of facility. In order to overcome this problem, the excellent drainage reuse system for non-point pollution load reduction in Korea Patent No. 10-0794491 attempts to reuse rainwater using a system of upflow flow filled with media, but in the case of the above patents, contamination in rainwater drainage By physically treating the material only at its source, the hydraulic instability for treating nonpoint pollutants due to rainfall cannot be properly overcome, and if the flow rate of rainfall exceeds the design capacity, the treated water can not be properly treated. There is a limit to reusing for purposes.

Accordingly, the present invention for solving the above problems is a jar-test according to the various characteristics of the contaminants contained in the rainfall effluent stored by introducing the initial excellent storage tank to overcome the hydraulic instability of the non-point pollutant treatment due to rainfall Reusable water supply system using rainfall effluent, which is characterized by increasing the removal efficiency of pollutants contained in rainfall effluent by adding appropriate inorganic flocculant, flocculent aid, and polymer flocculant and treating it through physical, chemical and biological treatment process. The task is to provide.

In addition, the present invention includes the most of the pollutants in the initial rainfall, considering that the rainfall standard of the general initial rainfall is 5 mm rainfall, introducing an initial rainfall storage tank that can store the rainfall of 5 mm in the target area, the initial rainfall Another object is to provide a reusable tap water system using rainfall runoff, characterized in that the initial rainfall containing most of the non-point pollutants stored in the reservoir is gradually and efficiently treated during the rain-free period.

Application of the above problem can be said that the introduction of the initial excellent storage tank according to the present invention is appropriate because the shorter the rainfall period is less the amount of non-point pollutants in the target area.

In addition, when using an external carbon source such as methanol for the denitrification of the above problems, in order to solve the problem of contamination of treated water by methanol, in the present invention, sulfur and limestone packed bed is introduced into the biological treatment unit, introduced for autotrophic denitrification The sulfur and limestone layer is a layer filled with agglomerates formed by mixing solid sulfur particles and limestone particles with an adhesive material, and is introduced to denitrate nitrate nitrogen from the bioactive carbon layer, which is an oxynitride layer, without contamination by organic matter. Another object of the present invention is to provide a reusable water supply device using rainfall runoff, which is characterized in that excellent water quality is obtained.

The present invention for solving the above problems in the reusable water supply apparatus through the removal of non-point pollutants of rainwater runoff in apartment areas, commercial areas and industrial areas,

An initial excellent treatment unit (A) for storing the initial rainfall in the target area and physically and chemically treating the initial rainfall;

A biological treatment part (B) for physically and biologically treating the excess water flowing in exceeding the treated water and the design flow rate of the initial excellent treatment part by a biofiltration;

Reusable water supply unit (C) having a reused water pipe for storing the treated water of the biological treatment unit, and recycling the stored treated water;

The reuse water supply apparatus using the rainfall runoff is characterized in that the problem solving means.

The present invention by the above-mentioned means to solve the problem, the initial rainfall containing most of the non-point pollutant during the occurrence of rain introduced an initial excellent storage tank to overcome the hydraulic instability of the non-point pollutant treatment due to rainfall and effectively By treating it to be used as reusable water through a biological treatment process, it is an advantage to enable effective reuse of rainwater as well as prevention of river pollution due to external spills of non-point pollutants.

In particular, the present invention is a case of applying the method of removing the total nitrogen (TN) contained in the initial rainfall by the nitrification process through the bioactive carbon layer and the autotrophic denitrification process through the sulfur and limestone packed bed as well as the removal of suspended solids. The advantage is that even contaminants in the dissolved phase can be removed.

Therefore, the present invention is to treat the non-point pollutants in the initial rainfall runoff in the sewage treatment area, the treatment of the overflow water in the combined sewage treatment area, the removal of the non-point pollutants introduced from the water supply source or dam upstream, the fire in the workplace such as factories, water emergency It can be used as a non-point pollution reduction facility that has a combined storage tank function, and is expected to be a highly available technology that can be combined with rainwater storage tanks in addition to the treatment of non-point pollutants generated in various development projects such as complex development.

According to a feature of the present invention for solving the above problems, the conventional non-point pollutant treatment facility is mainly a physical treatment method for removing a high specific gravity soil, etc., the present invention is a hydraulic treatment of non-point pollutant treatment. In order to overcome instability, it is equipped with a storage tank for storing the initial excellent water containing a large amount of non-point pollutants, and introduced a chemical treatment method called agglomeration process to reduce particulate suspended matter and dissolved substances contained in the non-point pollutants. Its effects are enhanced, and biological filtration is possible through biofiltration, so that even a small amount of harmful substances can be treated to ensure stable treatment water.

Hereinafter, the configuration of the present invention will be described in detail with reference to the accompanying drawings.

1 is a view schematically showing the entire apparatus of the reusable water supply system using the rainfall runoff according to the present invention, Figure 2 is a partial process diagram of a physical and chemical treatment apparatus for treating non-point pollutants in the initial rainwater according to the present invention 3 is a view showing a cross-sectional view of a biofiltration according to the present invention.

In the present invention, as shown in Figure 1 in the reusable water supply apparatus through the removal of non-point pollutants of rainwater runoff in apartment areas, commercial areas and industrial areas,

An initial excellent treatment unit (A) for storing the initial rainfall in the target area and physically and chemically treating the initial rainfall;

A biological treatment part (B) for physically and biologically treating the excess water flowing in exceeding the treated water and the design flow rate of the initial excellent treatment part by a biofiltration;

Reusable water supply unit (C) having a reused water pipe for storing the treated water of the biological treatment unit, and recycling the stored treated water;

The present invention relates to a reusable water supply apparatus using rainfall runoff.

The present invention is to maintain the reusable water quality by treating the non-point pollutants caused by rainfall in the apartment area, commercial area and industrial area through the initial excellent treatment unit and biological treatment unit using the reusable water supply device to store the rain water in the reused water department The apparatus for reusing is described in detail with respect to each processing apparatus as follows.

In the present invention, the reusable water supply device may also be referred to as a graywater apparatus.

Initial excellent treatment unit (A) in the present invention, as shown in Figure 2, the initial excellent storage tank 10 for receiving and storing the rainfall outflow water flowing out from the apartment area, commercial area, industrial area, etc. It consists of a rapid mixing tank (11), slow mixing tank (12), chemical storage tank (13) and settling tank (14) designed to remove contaminants physically and chemically.

And the biological treatment unit (B) is a biofiltration and treatment tank consisting of a bioactive carbon layer 21, granular sulfur and limestone packed layer 22, sand layer 23, gravel layer 24 as shown in FIG. 26) was designed to remove contaminants through biological treatment and filtration, and reused water part (C) is designed to be reused through the reused water pipe to use the treated water stored in the reused water storage tank (30).

In the present invention, the initial rainwater treatment unit (A) introduced an initial rainfall storage tank (10) capable of storing rainfall of 5 mm in the target area in consideration of the rainfall standard of the general initial rainwater is 5 mm. The initial rainfall effluent containing most of the nonpoint pollutants stored in the initial rainfall reservoir 10 is designed to be treated slowly within the subsequent rainfall-free period, and if the preceding rainfall period is short, the amount of nonpoint pollutants in the target area is small. It is not a consideration. The contaminant stored in the initial rainfall storage tank 10 is characterized in that the treatment process by inputting the appropriate inorganic coagulant, coagulant aid and polymer coagulant through the jar-test according to the properties.

In the initial excellent treatment unit (A), when the contaminants of the contaminants contained in the rainfall effluent, the fine particles contained in the water mainly carry a negative charge, these particles do not aggregate with each other because of repulsion, sediment removal It cannot be formed into larger particles that are easier. Therefore, in order to remove these particles, the zeta potential proportional to the magnitude of the electrical negative charge of the particles must be reduced. In other words, the coagulant is administered to reduce the zeta potential. The coagulant acts instantaneously with the particles at the time of input, so that the coagulant must be uniformly contacted in the aqueous solution to maintain agitation speed for mixing. The hydraulic retention time (HRT) should be 55 to 65 seconds, followed by rapid mixing. At this time, as the zeta potential of the particles is reduced, van der Waals forces, which are attractive forces between the particles, interact with each other, thereby forming an agglomeration process due to the bonding between the particles.

In the slow mixing tank 12, which is a subsequent process after the rapid mixing tank 11, the particles are substantially grown by the attraction force between the aggregated particles having almost no charge. In order to increase the growth rate, the stirring speed should be slow so that the grown particles are not destroyed. Unlike the rapid mixing tank 11, slow mixing is generally performed for 45 to 55 minutes. This particle formation process is called flocculation.

Therefore, the hydraulic retention time (HRT) required in the coagulation process is 55 to 65 seconds and 45 to 55 minutes for the rapid mixing tank 11 and the slow mixing tank 12, respectively. It turns out that the volume is about 1 / 60-1 / 42 compared with the tank 12. Reflecting this, as shown in FIG. 2, in the present invention, the rapid mixing tank 11 is designed to be located in the slow mixing tank 12 in consideration of installation advantages.

The flocculant used in the rapid mixing tank (11) is supplied from the chemical storage tank (13), the type of flocculant used in the present invention is roughly divided into Al-based, Fe-based and polymer coagulant, Al-based Al (OH) ₃ And Fe-based Fe (OH) ₃ is produced. This hydroxide forms a floc. Al water flocculants are mostly used in Korea's water purification plants, while in Europe and the United States, Fe is mainly used. The use of these flocculants is designed to be determined through jar-test due to the characteristics of non-point source that the difference of concentration of initial rainfall runoff is severe depending on the installation area of the device and the number of days of no rainfall.

The flocculant used in the present invention does not become a feature of the present invention because it is a type of flocculant commonly used.

In particular, considering that the average number of preparatory rainfall days in Korea is more than 10 days, the capacity of the physical and chemical treatment facilities of this initial water treatment unit can be installed on a very small scale, and the amount of flocculant required through jar-test is also required. There is an advantage that can provide enough time to determine. In addition, the existing non-point pollutant treatment facility treats nonpoint pollutants during the rainfall period, while abnormal treatment occurs due to an inconsistent flow rate and inflow concentration, whereas the treatment technology of rainfall runoff according to the present invention is stored after rain, without rainfall. It can be said to be very stable because it is treated slowly over a period of time.

And the rainwater and rainfall of the initial excellent treatment unit (A) is 5 mm or more rainwater is introduced into the biological filtration phase 20 which is a subsequent process. As shown in FIG. 3, the cross-sectional view of the biofiltration is composed of a bioactive carbon layer 21, a granular sulfur / limestone packed layer 22, a sand layer 23, a gravel layer 24, and a treatment tank 26.

The bioactive carbon layer 21 was introduced to nitrify the ammonia nitrogen (NH ₄ ⁺ -N) contained in the non-point pollutant due to rainfall with nitrate nitrogen (NO ₃ ^-- N). According to the inventor's prior research (Korean Patent Application No. 2009-0027836, filed on March 3, 2009), when the ceramic carrier is used in the nitrification reactor, the amount of adherent microorganism is about 250 mg / L, but the bioactive carbon carrier is used. In the results, it was possible to achieve more than 1,200 mg / L of adherent microorganism under optimum conditions. Therefore, the present invention also introduced a bioactive carbon packed bed for nitrification.

Then, the flow passing through the bioactive carbon layer 21 is moved to the granular state and the limestone packed layer 22. The flow through the bioactive carbon layer 21 contains nitrate nitrogen (NO ₃ ^-- N), the total nitrogen in the water (TN) through the denitrification process to convert the nitrate nitrogen to nitrogen gas (N ₂ ) ) Will be removed. Such denitrification is classified into heterotrophic denitrification and autotrophic denitrification. Since heterotrophic denitrification using an external carbon source causes expensive drug costs and high sludge production, autotrophic denitrification using sulfur has been introduced into the present invention as an alternative thereto. . Particularly, when methanol is used as a heterotrophic denitrification source, sulfur dioxide and alkali source are used as independent nutrient denitrifiers in which the COD rise does not occur in the present invention, because the COD in the treated water is increased and the value of recycled water is significantly inhibited. Limestone was used as a supplement.

The sand filter, the sand layer 23 introduced afterwards, is a conventional filtration system having a history of more than two centuries in Europe and its effect has been recognized. In general, slow sand filtration is used to filter 70 to 90 cm thick layers of sand at a filtration rate of about 4 to 5 m / day. Turbidity and bacteria are almost completely removed and soluble substances such as ammonia, iron, and manganese are well removed. It is known. In addition, the longer the duration of filtration, the gelatinous microbial film is formed up to several cm deep from the surface of the sand layer. Dissolved contaminants are biologically removed from the microbial membrane, and bacteria, pesticides, and ammonia can be adsorbed by the deep sand. However, the conventional slow sand filtration was performed in a continuous flow of water purification process. It has not been applied to batch flows due to properties.

In addition, the gravel layer 24 was introduced to prevent the loss of sand in the sand layer and for the solid-liquid separation into the treatment tank (26). In general, it is to replace the solid-liquid separation of the filtration phase to the perforated pipe, in the present invention replaced the role of the perforated pipe into the gravel layer 24 on the support 25 for supporting the biofiltration layer and introduced the treatment tank 26 . From this treatment tank 26, it is transferred to the reuse water tap portion C using power using a pump.

Reusable water supply unit (C) is composed of the reused water storage tank 30 and the reused water pipe, and stores the final treated water of the reused water device using the rainfall runoff according to the present invention, and then landscaping water, toilet through the network It is supplied to water and industrial water.

Hereinafter, preferred embodiments of the present invention will be described. The following examples are described for the purpose of illustrating the present invention in more detail, but the content of the present invention is not limited to the following examples.

Example

As a result of collecting and analyzing the initial rainfall flowing out from the road, the pollutant concentration of the initial rainfall was SS 94.7 mg / L, total nitrogen (TN) 12.3 mg / L, BOD 31.2 mg / L and COD 52.4 mg / L. The initial rainfall was treated using the reusable water supply apparatus according to the present invention as follows.

As a result of Jar-test, when the Al-based inorganic coagulant Al ₂ (SO ₄ ) ₃ · 14H ₂ O was added 5 mg / L, the optimum effluent quality could be achieved. Therefore, after rapid stirring for 60 seconds using the stirrer in the rapid mixing tank of the reusable water supply apparatus according to the present invention, the contaminant which was agitated for 50 minutes using the stirrer in the slow mixing tank was transferred to a precipitation tank for precipitation. As a result of measuring the concentration of contaminants in the treated water filtered through biofiltration, SS 0.2 mg / L, total nitrogen (TN) 1.2 mg / L, BOD 0.7 mg / L, COD 1.8 mg / L. This is excellent water quality corresponding to class Ib of Annex 1 of the Enforcement Decree of the Framework Act on Environmental Policy, which regulates the water quality of rivers, and it can satisfy the usage criteria of heavy water so that it can be reused as heavy water for various uses such as landscape water, toilet water or industrial water. I could confirm that it could.

As described in the above embodiment, the excellence of the reusable tap water apparatus using the rainfall runoff according to the present invention has been demonstrated, but the configuration of the present invention is not necessarily limited only to the above embodiments, and does not depart from the technical spirit of the present invention. Various substitutions and modifications are possible within the scope.

1 is a view schematically showing the entire apparatus of the reuse water supply apparatus using the rainfall runoff according to the present invention,

2 is a view showing a partial process of the physical and chemical treatment apparatus for treating non-point pollutants in the initial excellent rain according to the present invention,

3 is a view showing a cross-sectional view of the biofiltration according to the present invention.

Explanation of symbols on the main parts of the drawings

10: early excellent storage tank 11: rapid mixing tank

12: slow mixing tank 13: chemical storage tank

14: sedimentation tank 20: biofiltration

21: bioactive carbon layer 22: granular state / limestone packed layer

23: sand layer 24: gravel layer

25: support 26: treatment tank

30: reusable water storage tank

Claims (4)

In the reusable water system through the removal of non-point pollutants of rainwater from apartment, commercial and industrial areas, An initial excellent treatment unit (A) for storing the initial rainfall in the target area and physically and chemically treating the initial rainfall; A biological treatment part (B) for physically and biologically treating the excess water flowing in exceeding the treated water and the design flow rate of the initial excellent treatment part by a biofiltration; Reusable water supply unit (C) having a reused water pipe for storing the treated water of the biological treatment unit, and recycling the stored treated water; Reusable water device using rainfall runoff, characterized in that consisting of. The method of claim 1, The initial excellent treatment unit (A) is an initial excellent storage tank (10) for receiving and storing the rainfall outflow water flowing out from the apartment area, commercial area, industrial area, etc., a rapid mixing tank (11) for cohesion treatment of the incoming rainwater, slow Recycling water system using a rainwater effluent, characterized by consisting of a mixing tank (12), chemical storage tank (13) and settling tank (14) to remove contaminants physically and chemically. The method of claim 1, The biological treatment unit (B) is composed of a biological filtration and treatment tank 26 composed of a bioactive carbon layer 21, granular sulfur and limestone packed layer 22, sand layer 23, gravel layer 24 and biological treatment and Reusable water supply system using rainfall runoff, characterized in that to remove contaminants through filtration. The method of claim 2, The rapid mixing tank (11) is reused water apparatus using rainfall runoff, characterized in that the volume of 1/60 ~ 1/42 compared to the slow mixing tank (12).

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