KR101616825B1 - Small-scale sewage and wastewater treatment system - Google Patents

Abstract

The present invention relates to a small scale sewage and wastewater treatment system and, more particularly, to a small scale sewage and wastewater treatment system which comprises an anaerobic tank, an electrolysis tank, an aerobic tank, a precipitation tank, a bottom-up sand filtration device, a PUV treatment tank, a ball-mill crushing device, and a sludge drying system. Further, the sewage and wastewater treatment system of the present invention removes nitrogen and phosphorous, generates dried sludge cake by drying the sludge, and discharges treated water by finally sterilizing the wastewater by pulsed UV. The sewage and wastewater treatment system of the present invention minimizes discharging contaminant residues and reduces water content in sludge at low costs.

Description

[0002] Small-scale sewage and wastewater treatment systems

The present invention relates to a small scale wastewater treatment system, and more particularly, to a small scale wastewater treatment system comprising an anoxic tank, an electrolysis tank, an exhalation furnace, a sedimentation tank, a bottom-up type filtration device, a PUV treatment tank, a ball mill crushing device and a sludge drying system, The sludge is dried in a sludge drying system to generate a sludge dried cake. The sludge is dried and sterilized by pulsed UV to discharge the treated water. .

In general, the domestic sewage treatment facility uses standard activated sludge method or the modified or modified method of the above method, and the removal efficiency of nutrients according to the method is less than 20%. In order to comply with the water quality standard being strengthened, Is inevitable.

The A ₂ / O process, UCT process, and VIP process, which are applied in foreign countries, are not applied due to the low concentration of organic substances due to the combined sewage exclusion system in Korea, and about 78% However, the amount of sewage treated by actual sewage treatment facilities is estimated to be less than the actual sewage treatment facilities due to lack of sewerage maintenance and lack of sewage treatment facilities. In addition, the wastewater produced in small areas, livestock wastewater, Wastewater generated in industrial complexes or factories is discharged directly to the water system due to lack of facilities or absence of treatment facilities.

Conventional conventional wastewater treatment methods are mainly focused on physical treatment, chemical treatment, and biological treatment, and physical treatment is performed by separating solids in the wastewater from gravity by liquid or by other physical methods Chemical treatment is applied to the wastewater to treat chemicals such as neutralization, pH adjustment, redox, coagulation, adsorption, etc., and the treatment cost is increased due to the increase of chemical cost and sludge generation amount. In order to overcome the disadvantages of the physico-chemical method, the biological advanced treatment method is applied. However, in case of the biological advanced treatment method, the treatment efficiency is greatly influenced by the concentration of organic matters and nutrients in the influent water. The reliability of the nutrient removal rate is low.

In order to solve the above problems, an electrolytic apparatus is studied and installed. Prior arts using electrolysis include Korean Patent No. 10-1306980, which discloses a water treatment apparatus including a biological reaction process, And electrolytic means for electrolyzing the water to be treated so as to supply iron ions to the water to be treated, wherein the electrolytic means comprises: an electrolytic bath passing through the water to be treated flowing into the aerobic tank; And a power supply unit for supplying electric power to the electrode unit. The steel plate is heat treated for 3 hours and then heat-treated, thereby providing a water treatment apparatus using iron electrolysis.

Conventional wastewater treatment processes such as the conventional electrolysis process are difficult to install in a small space and can not be operated with the focus on removing phosphorus in wastewater and can not avoid the discharge of residual pollutants There is a problem that the bactericidal action of viruses and pathogenic bacteria in the treated water is low.

On the other hand, existing CSOs treatments were restricted to suspended solids (SS) and showed vulnerability to waterborne diseases. Recently, there has been a move to regulate pathogenic Escherichia coli in Korea, and additional processes and new processes are required for existing treatment methods . Conventional disinfection methods include UV process, chlorine method, ozone method, chlorine disinfection byproduct disposal, low ozone economical efficiency, UV pretreatment process, etc. Has come.

In addition, various methods such as vacuum pressure, compression force, and centrifugal force are applied to reduce the moisture content of the sludge, which can be economically treated by reducing the water content of the sludge generated from the wastewater treatment plant.

However, thermal dehydration method and centrifugal force method, which are methods of dehydration by thermocompression force, have a disadvantage that energy consumption is large and it is difficult to expand them universally.

Korean Patent No. 10-1306980 (2013.09.04.)

The present invention relates to a treatment facility capable of removing residual pollutants in wastewater treatment using a conventional electrolysis process as described above and a treatment facility capable of being installed in a small area and a small facility having a small lot, It is an object of the present invention to provide a sewage / wastewater treatment system capable of solving the problem of pathogenic bacteria and viruses such as super bacteria, minimizing the emission of residual pollutants and reducing the water content of the sludge and enabling economical treatment .

The small scale wastewater treatment system of the present invention includes an anoxic tank 100, an electrolysis tank 200, an oxic tank 300, a settling tank 400, a bottom-up four-way filtering device 500, And a PUV treatment tank 600.

The anoxic tank 100 is supplied with the nitrate nitrogen-containing wastewater generated through the nitrification process in the aerobic tank 300 through an internal transportation process, and is then subjected to denitrification, and nitrogen gas generated in the denitrification process is discharged into the atmosphere .

The electrolytic bath 200 dissolves phosphorus using electrolysis.

The oxic tank 300 performs a nitrification process in which ammonia in the influent water is oxidized to become nitric acid and a process in which the dissolved phosphorus is removed.

The sedimentation tank 400 performs sludge transportation and solid-liquid separation of suspended particles, and removes remaining residues and coagulates and removes fine suspended particles (SS) by injecting a flocculant into the sedimentation tank.

The bottom-up four-way filter unit 500 filters the harmful components with sand particles to remove phosphorus and nitrate nitrogen by injecting coated iron salts and methanol.

The PUV treatment tank 600 disinfects inflow water flowing through the PUV treatment tank 600 using a PUV light source (Pulsed Ultra Violet) 610 and a reflection plate 620.

The bottom-up four-way filter 500 has a filter layer formed of sand having a particle size of 0.9 mm to 1.1 mm, and the filtration layer is formed in an amount of 45% or more with respect to the internal volume of the bottom-up filter.

The PUV treatment tank 600 is made up of a PUV light source 610 irradiating a pulsed ultraviolet ray having a wavelength band of 185-280 nm and an aluminum reflector 620 having an aluminum foil as its surface.

The PUV light source 610 uses either a surface light source or a point light source.

The electrolytic bath 200 reacts with the dissolved oxygen in the electrolytic reaction vessel by moving the ferrous ions generated on the surface of the iron (Fe) electrode of the anode to the surface of the iron electrode of the cathode according to the current flow in the aqueous solution, It has the principle that iron is oxidized and phosphorus is removed and phosphorus is removed.

The sewage / wastewater treatment system additionally includes a ball milling apparatus 700 and a sludge drying system 800.

The ball milling apparatus 700 is provided therein with a stirrer 720 which is operated at a rotational speed of 6 to 22 m / s. The ball milling apparatus 700 has a glass ball or a metal ball having a diameter of 4 mm to 9 mm, And the precipitated sludge generated from the settling tank 400 flows into the sludge drying system 800. The sludge is then crushed and discharged to the sludge drying system 800. The moisture generated during the sludge crushing process is returned to the settling tank 400. [

The sludge drying system 800 includes a dewatering unit 810, a solar collector 820, a heat exchanger 830, a boiler 840, an underground heat exchanger 870, a geothermal heat pump 860, a sludge drying tank 840 ), And a pump (not shown).

The dehydrator 810 dehydrates the sludge using a centrifugal separator using a centrifugal force and transfers the dehydrated sludge to a sludge drying tank 840. The maximum temperature of the solar collector 820 is 300 ° C or higher and the maximum operation temperature is 250 ° C or higher Exchanged in the heat exchanger 830 using the PTC (Parabolic Trough Collector) type solar collector of the PTC type, and supplies the thermal energy to the sludge drying tank 840. The geothermal heat exchanger 870 supplies the geothermal heat pump 860 And supplies the heat energy to the sludge drying tank 840. The boiler 850 is operated supplementarily when the temperature of the heat source collected from the solar collector is less than 80 ° C and supplies it to the sludge drying tank 840.

The pump (not shown) is installed between the solar heat exchanger 820 and the heat exchanger 830, between the heat exchanger 830 and the sludge drying tank 840, between the boiler 850 and the sludge drying tank 840, Is installed between the geothermal heat pump 860 and the geothermal heat pump 860 and between the geothermal heat pump 860 and the sludge drying tank 840 to circulate heat medium including heat energy.

When the temperature of the heating medium flowing out of the heat exchanger 830 and the geothermal heat pump 860 connected to the solar collector 820 is less than 80 ° C, the pump installed between the heat exchanger 830 and the sludge drying tank 840, The operation of the pump installed between the heat pump 860 and the sludge drying tank 840 is stopped and the sludge drying tank 840 receives the heat source from the solar collector 820 and the boiler 850, Dried and discharged.

The flocculant added to the sedimentation tank 400 is 30 to 70 parts by weight of aluminum hydroxide (Al (OH) ₃ ) having a concentration of aluminum oxide (Al ₂ O ₃ ) of 55 to 60% HCl) and acetic acid (CH ₃ COOH) at a concentration of 70 to 95% in a proportion of 2 to 32 parts by weight to obtain a primary mixture, and the primary mixture, dolomite, limestone, And activated silica powder were mixed at a weight ratio of 1: 0.5 to 2: 0.1 to 2: 00.5 to 2 and heated to 55 to 60 ° C under a pressure of 10 to 300 kgf / cm ^2. Then, 100 parts by weight of aluminum hydroxide (AlOH ₃ ) 5 to 25 parts by weight of caustic soda (NaOH) having a concentration of sodium oxide (Na 2 O) of 10 to 40% is mixed with the mixture and stirred for a predetermined time. The mixture is stirred at a temperature of 120 to 200 ° C for 3.5 to 30 minutes, (CH ₃ COOH) in the mixture of the flocculant, the hydrogen ion and the hydroxyl ion bind to each other to form a neutralization reaction The attraction force of the fine particles in the water is increased.

The anoxic tank (100) is provided with two anoxic tank (1) and anoxic tank (2).

The sludge drying system 800 further includes a temperature sensor (not shown) and a control device (not shown) for measuring the temperature of the heating medium. The temperature sensor includes a hot water outlet of the heat exchanger 830, a sludge drying tank 840 ) And the geothermal heat pump (860) hot water outlet, respectively. The control device (not shown) receives the temperature information of the hot water outlet of the heat exchanger 830 and the hot water outlet of the geothermal heat pump 860 by a temperature sensor The pump installed between the heat exchanger 830 and the sludge drying tank 840 stops the operation of the pump between the geothermal heat pump 860 and the sludge drying tank 840. When the boiler 850 ).

The ball milling apparatus 700 is crushed by the shear frictional force and heat generated between the metal balls to be agitated and driven for a predetermined period of time by alternate control to clean the ball and screen net 730.

The sludge drying tank 840 includes a gas outlet for treating the gas generated during the sludge drying process and a return water treatment device for collecting moisture generated during the drying process and transporting the water to the settling tank 400, A plurality of modules including a heat plate in contact with a tube through which a heating medium (water) for transferring a heat source flows in the tank and a drying space in which the sludge is dried between the heat plates is installed.

According to the present invention, it is possible to minimize residual pollutants, to install in small areas and small facilities having few sites, and to solve the problem of pathogenic bacteria and viruses such as super bacteria found in domestic rivers, especially urban rivers And the water content of the generated sludge is reduced, and the sludge can be economically treated by utilizing renewable energy such as solar heat or geothermal energy.

1 is a schematic process diagram of a small scale wastewater treatment system of the present invention.
2 is a schematic view of a ball milling apparatus as an apparatus for constituting a small scale wastewater treatment system according to the present invention.
3 is a schematic view of a sludge drying system included in a small scale wastewater treatment system of the present invention.
4 is a view showing the principle of one module constituting the PUV treatment tank included in the small scale wastewater treatment system of the present invention.
FIG. 5 is a view showing a PUV processing unit in which one module of FIG. 4 is connected horizontally in a plurality of units.

The present invention will be described in detail with reference to a "small-scale sewage / wastewater treatment system" which will be readily apparent to those of ordinary skill in the art, and a detailed description thereof will be omitted. Also, the terms defined in the present specification and claims should not be construed as limiting, but may be changed according to the intention or custom of the operator, and interpreted in terms of meaning and concept consistent with the technical idea of the present invention.

In one aspect of the present invention,

2 is a schematic view of a ball milling apparatus as an apparatus for constituting a small scale sewage / wastewater treatment system according to the present invention. FIG. 3 is a schematic view of a small- 4 is a view showing the principle of one module constituting the PUV treatment tank included in the small scale wastewater treatment system of the present invention, In which a plurality of modules are horizontally connected to one another.

1, the small scale sewage / wastewater treatment system of the present invention includes an anoxic tank 100, an electrolysis tank 200, an oxic tank 300, a settling tank 400, a bottom-up four-way filtering device 500 and a PUV treatment tank 600, .

The anoxic tank 100 is supplied with the nitrate nitrogen-containing wastewater generated through the nitrification process in the aerobic tank 300 through an internal transportation process, and is then subjected to denitrification, and nitrogen gas generated in the denitrification process is discharged into the atmosphere .

It is preferable that the anoxic tank (100) is provided with two anoxic tank (1) and anoxic tank (2).

The electrolytic bath 200 dissolves phosphorus using electrolysis.

The electrolytic bath 200 reacts with the dissolved oxygen in the electrolytic reaction vessel by moving the ferrous ions generated on the surface of the iron (Fe) electrode of the anode to the surface of the iron electrode of the cathode according to the current flow in the aqueous solution, It has the principle that iron is oxidized and phosphorus is removed and phosphorus is removed.

The mechanism of metal hydroxide formation when an iron electrode is used as an electrochemical oxidation method in which iron is precipitated by passing current through DC / DC converter on the surface of the iron plate mounted on the iron deposition apparatus of the electrolytic bath 20, same.

(Anode)

Fe ^- > Fe < ² + > + 2e ^-

Fe ²⁺ ? Fe ³⁺ + 3e ^-

FOH ^- > 2H ₂ O + O ₂ + 4e ^-

(Cathode)

H ₂ O → H ⁺ + OH ^-

Fe ³⁺ + PO ₄ ^3- → FePO ₄ ↓

Fe ³⁺ + 3H ₂ O -> Fe (OH) ₃ ↓ + 3H ⁺

The generated iron salts and phosphorus in the reaction tank are adsorbed and removed on the iron oxide and can be treated regardless of the phosphorus treatment rate and the phosphorus concentration which are faster than the biological removal.

Experimental Example  : Phosphorus removal efficiency

The dose of KH ₂ PO ₄ was adjusted from 39.2 to 19.5 mg / l, and no iron electrode plate was used in the fourth step. It was shown that the phosphorus removal rate in the electrolysis tank using iron was higher and the iron concentration was higher as the phosphorus load was higher.

number 1 No.2 number 3 No. 4 Load mg / l 39.2 30.1 19.5 19.5 PO ₄ -P Effluent 3.2 3.0 2.6 16.5 R.E. (%) 84.6 85.2 89.2 23.9 Iron concentration mg / l 55.1 60.9 78.3 none HTR / SRT hr / day 8/6 8/6 8/6 8/6

The anode of the electrolytic bath may be replaced by an aluminum material.

The oxic tank 300 performs a nitrification process in which ammonia in the influent water is oxidized to become nitric acid and a process in which the dissolved phosphorus is removed.

The sedimentation tank 400 performs sludge transportation and solid-liquid separation of suspended particles, and removes remaining residues and coagulates and removes fine suspended particles (SS) by injecting a flocculant into the sedimentation tank.

In the method for producing the acetic acid-added coagulant,

(a) 30 to 70 parts by weight of aluminum hydroxide (Al (OH) ₃ ) having a concentration of aluminum oxide (Al ₂ O ₃ ) of 55 to 60%, 10 to 40 parts by weight of 30 to 35% Obtaining a first mixture at a ratio of acetic acid (CH ₃ COOH) at a concentration of 70 to 95% at 2 to 32 parts by weight;

(b) mixing the primary mixture, dolomite, limestone, and active quartz sand powders obtained in the step (a) in a weight ratio of 1: 0.5 to 2: 0.1 to 2: 0.5 to 2 ;

(c) heating the mixed mixture obtained in steps (a) and (b) to a temperature of 55 to 60 ° C under a pressure of 10 to 300 kgf / cm 2;

(d) adding to the mixture heated in step (c) 5 to 25 parts by weight of caustic soda (NaOH) having a concentration of sodium oxide (Na ₂ O) of 10 to 40% relative to 100 parts by weight of aluminum hydroxide (AlOH ₃ ) Injecting and mixing the mixture;

(e) stirring the mixed mixture in the step (d) for a predetermined period of time;

(f) reacting the agitated mixture in the step (e) at a temperature of 120 to 200 ° C for 3.5 to 12 hours; And

(g) cooling the reaction product to a temperature of 30 to 40 ° C in the step (f).

The flocculant added to the sedimentation tank 400 is 30 to 70 parts by weight of aluminum hydroxide (Al (OH) ₃ ) having a concentration of aluminum oxide (Al ₂ O ₃ ) of 55 to 60% HCl) and acetic acid (CH ₃ COOH) at a concentration of 70 to 95% in a proportion of 2 to 32 parts by weight to obtain a primary mixture, and the primary mixture, dolomite, limestone, And activated silica powder were mixed at a weight ratio of 1: 0.5 to 2: 0.1 to 2: 00.5 to 2 and heated to 55 to 60 ° C under a pressure of 10 to 300 kgf / cm ^2. Then, 100 parts by weight of aluminum hydroxide (AlOH ₃ ) 5 to 25 parts by weight of caustic soda (NaOH) having a concentration of sodium oxide (Na 2 O) of 10 to 40% is mixed with the mixture and stirred for a predetermined time. The mixture is stirred at a temperature of 120 to 200 ° C for 3.5 to 30 minutes, (CH ₃ COOH) in the mixture of the flocculant, the hydrogen ion and the hydroxyl ion bind to each other to form a neutralization reaction The attraction force of the fine particles in the water is increased.

Experimental Example  : Coagulation characteristic test

The flocculant composition was treated at a final concentration of 20 mg / l in the raw water collected at the S sewage terminal treatment plant in Gwangju Metropolitan City and the raw water and treated water were treated at a rate of 250 rpm for about 1 minute using a Jar-tester The mixture was rapidly stirred and stirred at 30 rpm for 30 minutes, and then allowed to stand for 30 minutes. Then, the raw water and treated water were collected and the basicity, turbidity and pH thereof were measured. For comparison, commercially available polychlorinated aluminum (PAC) was used. The results are shown in Table 2 below.

Test Items Before processing (raw water) After treatment (present invention) After the treatment (Comparative Example) unit basicity 40 52 43 % Turbidity 1.254 0.802 0.957 NTU pH 5.3 7.2 6.7 -

The flocculant 40 may be replaced by a generally usable material.

The bottom-up four-way filter unit 500 filters the harmful components with sand particles to remove phosphorus and nitrate nitrogen by injecting coated iron salts and methanol.

The bottom-up four-way filter 500 has a filter layer formed of sand having a particle size of 0.9 mm to 1.1 mm, and the filtration layer is formed in an amount of 45% or more with respect to the internal volume of the bottom-up filter.

The PUV treatment tank 600 disinfects inflow water flowing through the PUV treatment tank 600 using a PUV light source (Pulsed Ultra Violet) 610 and a reflection plate 620.

2 and 3, the lower wastewater treatment system additionally includes a ball milling apparatus 700 and a sludge drying system 800.

Referring to FIG. 2, the ball milling apparatus 700 includes a stirrer 720 which is operated at a rotation speed of 6 to 22 m / s, and a ball or metal ball having a diameter of 4 mm to 9 mm, And the precipitated sludge generated from the settling tank 400 flows into the sludge drying system 800. The moisture generated during the sludge crushing process is returned to the settling tank 400. [

The ball milling apparatus 700 is crushed by the shear frictional force and heat generated between the metal balls to be agitated and driven for a predetermined period of time by alternate control to clean the ball and screen net 730.

3, the sludge drying system 800 includes a dewatering device 810, a solar collector 820, a heat exchanger 830, a boiler 840, an underground heat exchanger 870, a geothermal heat pump 860, A sludge drying tank 840, and a pump (not shown).

The dehydrator 810 dehydrates the sludge using a centrifugal separator using a centrifugal force and transfers the dehydrated sludge to a sludge drying tank 840. The maximum temperature of the solar collector 820 is 300 ° C or higher and the maximum operation temperature is 250 ° C or higher Exchanged in the heat exchanger 830 using the PTC (Parabolic Trough Collector) type solar collector of the PTC type, and supplies the thermal energy to the sludge drying tank 840. The geothermal heat exchanger 870 supplies the geothermal heat pump 860 And supplies the heat energy to the sludge drying tank 840. The boiler 850 is operated supplementarily when the temperature of the heat source collected from the solar collector is less than 80 ° C and supplies it to the sludge drying tank 840.

The pump (not shown) is installed between the solar heat exchanger 820 and the heat exchanger 830, between the heat exchanger 830 and the sludge drying tank 840, between the boiler 850 and the sludge drying tank 840, Is installed between the geothermal heat pump 860 and the geothermal heat pump 860 and between the geothermal heat pump 860 and the sludge drying tank 840 to circulate heat medium including heat energy.

When the temperature of the heating medium flowing out of the heat exchanger 830 and the geothermal heat pump 860 connected to the solar collector 820 is less than 80 ° C, the pump installed between the heat exchanger 830 and the sludge drying tank 840, The operation of the pump installed between the heat pump 860 and the sludge drying tank 840 is stopped and the sludge drying tank 840 receives the heat source from the solar collector 820 and the boiler 850, Dried and discharged.

The sludge drying system 800 further includes a temperature sensor (not shown) and a control device (not shown) for measuring the temperature of the heating medium. The temperature sensor includes a hot water outlet of the heat exchanger 830, a sludge drying tank 840 ) And the geothermal heat pump (860) hot water outlet, respectively. The control device (not shown) receives the temperature information of the hot water outlet of the heat exchanger 830 and the hot water outlet of the geothermal heat pump 860 by a temperature sensor The pump installed between the heat exchanger 830 and the sludge drying tank 840 stops the operation of the pump between the geothermal heat pump 860 and the sludge drying tank 840. When the boiler 850 ).

The sludge drying tank 840 includes a gas outlet for treating the gas generated during the sludge drying process and a return water treatment device for collecting moisture generated during the drying process and transporting the water to the settling tank 400, A plurality of modules including a heat plate in contact with a tube through which a heating medium (water) for transferring a heat source flows in the tank and a drying space in which the sludge is dried between the heat plates is installed.

Referring to FIG. 4, the PUV treatment tank 600 includes a PUV light source 610 irradiating a pulsed ultraviolet ray having a wavelength band of 185-280 nm and an aluminum reflector 620 having a quartz cell as an outer surface.

The PUV light source 610 uses either a surface light source or a point light source.

The aluminum used for the aluminum reflector may be any one of aluminum 1050, aluminum 6061, aluminum 5052, aluminum mirror, and aluminum foil (Alu 1000).

The longest distance between the PUV light source and the aluminum reflector shall not exceed 1 meter.

It is preferable to provide a flow rate control device for controlling the amount of wastewater flowing in order to prevent the wastewater discharged from the electrolytic bath from suddenly flowing into the PUV treatment tank.

The flow control device may be adapted to control the flow rate according to the opening and closing of the water gate.

Referring to FIG. 5, it can be seen that the module of FIG. 4 is connected horizontally continuously to improve the water treatment ability.

The process using pulsed UV has almost no disinfection byproducts, is economical compared to ozone, has less effect by SS than conventional UV process, and has a very short reaction time, which makes the sterilizing action of viruses and pathogenic bacteria in the treated water economical But can be effectively strengthened.

According to the present invention, it is possible to minimize residual pollutants, to install in small areas and small facilities having few sites, and to solve the problem of pathogenic bacteria and viruses such as super bacteria found in domestic rivers, especially urban rivers And the water content of the generated sludge is reduced, and the sludge can be economically treated by utilizing renewable energy such as solar heat or geothermal energy.

While the present invention has been described with reference to a limited number of embodiments and drawings, it is to be understood that the invention is not limited thereto and that various changes and modifications within the spirit and scope of the appended claims, Of course, it is possible to modify it.

100: Anoxic
200: electrolysis tank 300: aerobic tank
400: sedimentation tank 500: bottom-up type filtration device
600: PUV treatment tank
610: PUV light source 620: aluminum reflector
700: Ball milling device
710: body 720: stirrer
730: Screen net 740: Motor
800: Sludge drying system
810: Dewatering device 820: Solar collector
830: Heat exchanger 840: Sludge drying tank
850: Boiler 860: Geothermal heat pump
870: Underground heat exchanger

Claims (13)

In a small scale wastewater treatment system,
The sewage / wastewater treatment system comprises an anoxic tank, an electrolysis tank, an aerobic tank, a sedimentation tank, a bottom-up type filtration device, a PUV treatment tank, a ball mill crushing device and a sludge drying system,
Wherein the anoxic tank is supplied with the nitrate nitrogen-containing wastewater generated through the nitrification process in the aerobic tank through an internal transportation process, and performs denitrification, discharges the nitrogen gas generated in the denitrification process to the atmosphere,
Wherein the electrolytic bath dissolves phosphorus using electrolysis,
Wherein the aerobic tank performs a nitrification process in which ammonia in the influent water is oxidized to become nitric acid and a process of removing the eluted phosphorus,
The sedimentation tank performs sludge transportation and solid-liquid separation of suspended particles, removes residual residues and cohesively removes fine suspended particles (SS) by injecting coagulant into the sedimentation tank,
The bottom-up four-way filter device injects coated iron salts and methanol to remove phosphorus and nitrate nitrogen, the harmful components are filtered by sand particles,
The PUV treatment tank is made of a PUV light source (Pulsed Ultra Violet) and an aluminum reflector to disinfect the inflow water flowing through the PUV treatment tank, a PUV light source for irradiating pulsed ultraviolet rays having a wavelength band of 185 to 280 nm And an aluminum reflector having a surface,
The ball milling apparatus is equipped with a stirrer which is operated at a rotational speed of 6 to 22 m / s and is filled with 55 to 85% of the volume of the crusher by a glass ball or a metal ball having a particle diameter of 4 mm to 9 mm, The sludge is discharged into the sludge drying system, the moisture generated during the sludge crushing process is returned to the sedimentation tank,
The sludge drying system is composed of a dehydrator, a solar collector, a heat exchanger, a boiler, an underground heat exchanger, a geothermal heat pump, a sludge drying tank and a pump,
The dewatering device dehydrates the sludge by using a centrifugal force using centrifugal force to move the sludge to the sludge drying tank,
The solar collector is heat exchanged in the heat exchanger using a PTC (Parabolic Trough Collector) type solar collector having a maximum focal point temperature of 300 ° C or higher and a maximum operation temperature of 250 ° C or higher, thereby supplying thermal energy to the sludge drying tank,
The underground heat exchanger supplies heat energy to the sludge drying tank through a geothermal heat pump,
The boiler is supplementarily activated when the temperature of the heat source collected from the solar collector is less than 80 캜 and supplied to the sludge drying tank,
The pump is installed between the solar heat exchanger and the heat exchanger, between the heat exchanger and the sludge drying tank, between the boiler and the sludge drying tank, between the geothermal heat exchanger and the geothermal heat pump, between the geothermal heat pump and the sludge drying tank, Lt; / RTI &
When the temperature of the heat medium flowing out of the heat exchanger connected to the solar collector and the heat pump is lower than 80 ° C, the pump installed between the heat exchanger and the sludge drying tank, the pump installed between the geothermal heat pump and the sludge drying tank,
The sludge drying tank receives the heat source from the solar collector and the boiler, dries the sludge and discharges the sludge.
The flocculant added to the sedimentation tank is 30 to 70 parts by weight of aluminum hydroxide (Al (OH) 3) having a concentration of aluminum oxide (Al 2 O 3) of 55 to 60%, 10 to 40 parts by weight of hydrochloric acid (HCl) (CH3COOH) in an amount of 2 to 32 parts by weight and a concentration of 70 to 95%, and mixing the primary mixture, dolomite, limestone and activated silica powder at a ratio of 1: 0.5 (Na2O) was added to 100 parts by weight of aluminum hydroxide (AlOH3) at a temperature of 55 to 60 DEG C under a pressure of 10 to 300 kgf / cm < And 5 to 25 parts by weight of caustic soda (NaOH) to 40%. The mixture is agitated for a certain period of time. The mixture is stirred at a temperature of 120 to 200 ° C. for 3.5 to 12 hours and then cooled at 30 to 40 ° C. Acetic acid (CH3COOH) in the mixture of the flocculant causes a hydrogenation reaction with a hydroxide ion and a hydroxide ion to cause a neutralization reaction Small, and the waste water treatment system, comprising a step of increasing the attraction force of the fine particles in the. The method according to claim 1,
Wherein the bottom-up four-way filter device has a filtration layer formed of sand having a particle size of 0.9 mm to 1.1 mm, and the filtration layer is formed in an amount of 45% or more with respect to the internal volume of the bottom- Processing system. delete The method according to claim 1,
Wherein the PUV light source is one of a surface light source and a point light source. The method according to claim 1,
In the electrolytic bath, the divalent iron ions generated on the surface of the iron (Fe) electrode of the anode move to the surface of the iron electrode of the cathode according to the flow of current in the aqueous solution and react with dissolved oxygen in the electrolytic reaction tank, And the phosphorus is removed. delete delete delete delete The method according to claim 1,
Wherein the anoxic tank is provided with two anoxic tank (1) and anoxic tank (2). The method according to claim 1,
The sludge drying system
A temperature sensor and a control device for measuring the temperature of the heating medium,
The temperature sensor is installed in the heat exchanger hot water outlet, the sludge drying tank, and the geothermal heat pump hot water outlet,
The control device receives the temperature information of the heat exchanger hot water outlet and the geothermal heat pump hot water outlet by a temperature sensor, and when the temperature information is less than 80 ° C, the controller controls the pump installed between the heat exchanger and the sludge drying tank, the geothermal heat pump and the sludge drying tank And the boiler is operated while stopping the operation of the pump between the boiler and the boiler. The method according to claim 1,
Wherein the ball mill crushing device is crushed by the shear frictional force and heat generated between the metal balls to be agitated and driven in a reverse direction for a predetermined time by alternate control to clean the ball and screen net. The method according to claim 1,
The sludge drying tank is composed of a gas outlet for treating gas generated during the sludge drying process, a return water treatment device for collecting water generated during the drying process to the sedimentation tank, and a cake discharger for discharging the dried sludge cake,
Wherein a plurality of modules including a heat plate in contact with a pipe through which a heating medium (water) for transferring a heat source flows in the tank and a drying space in which sludge is dried between the heat plates are installed.

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