Title of Invention

METHOD OF MIXING AND PURIFYING LANDFILL LEACHATE OF HOUSEHOLD WASTE AND SUPERNATANT WATER OF FOOD WASTE

Abstract

A method of mixing and purifying landfill leachate of household waste and supernatant water of food waste, the method comprising: a mixing process for collecting and mixing leachate produced in a landfill of household waste and supernatant water produced in food waste, in a ratio of 1 to 0.8 - 1.2; an anaerobic digestion process for removing high concentration non-biodegradable organics of the mixed waste water through digestion;a denitrification / nitrification process for removing nitrogen and non-biodegradable organic materials of the treated water from the anaerobic digestion process; a chemical coagulation process for condensing and precipitating remaining organic materials of the treated water from the denitrification / nitrification process; and an oxidation coagulation process for removing remaining organic materials and color of the treated water from the chemical coagulation process.

Full Text

METHOD OF MIXING AND PURIFYING LANDFILL LEACHATE OF HOUSEHOLD WASTE AND SUPERNATANT WATER OF FOOD WASTE TECHNICAL FIELD The present invention relates to an efficient and economical purification method by which landfill leachate of household waste containing high concentration nitrogen and supernatant water produced in a treatment process of food waste are mixed and treated. BACKGROUND ART Generally, unlike ordinary household sewage having an almost constant characteristic of water quality, the characteristic of water quality of leachate produced in a landfill of household waste appears in a variety of forms according to the type and amount of filling waste, the shape of the landfill, the method of reclamation, the amount of rainfall, climate conditions, and the degree of hardening, in particular, with the passage of the reclamation period, organic materials gradually decrease, thereby changing the non-biodegradable state in which it is difficult for biodegradation to happen, while nitrogen increases. Accordingly, the leachate becomes waste water which is very difficult to be treated in a single treatment process. In relation to a method of purifying the landfill leachate of household waste, a method of using microorganisms for effective treatment of high concentration nitrogen included in the leachate is generally used. In order to use the nitrogen treatment by microorganisms, the concentration ratio of organic materials to total nitrogen (biochemical oxygen demand (BOD)/T-N) should be maintained at least 3 ~ 5. However, in the case of landfill leachate of household waste which is over three years old, the concentration ratio is mostly equal to or less than 1, which is very low, and a large amount of an organic carbon source should be provided in order to perform an appropriate nitrogen treatment. However, since methanol which is generally used as an organic carbon source is expensive, the overall treatment cost of leachate increases. Also, in the early stage up to 1 or 2 years after reclamation begins, the BOD/COD ratio indicating the possibility of biological treatment (degradation by microorganisms) is maintained to be equal to or greater than 0.4, and the concentration of organic materials shows its maximum value. Here, COD is chemical oxygen demand. Accordingly, the state is appropriate for being treated by microorganisms. However, with the passage of time since the reclamation, the concentration of nitrogen increases due to ammonia nitrogen produced in the degradation process of household waste, while the concentration of organic materials decreases instead due to natural degradation reaction in the landfill itself. In terms of the structure of the whole organic materials, the share of organic materials that can be biologically treated decreases, while the share of recalcitrant organic materials increases. Accordingly, normal nitrogen treatment by microorganisms is made to be difficult as a whole. As a technology for solving these problems, a technology for removing nitrified nitrogen by using an organic carbon source included in waste water inflowing into a sump has been disclosed in Korean Patent No. 432645. However, only with the organic carbon source in waste water, organic materials (BOD) are not enough, and therefore nitrogen cannot be sufficiently removed. Also, a technology for introducing methanol as an external carbon source in order to supplement an organic carbon source which is not enough in the waste water, has been disclosed in Korean Patent No. 436043, but as described above, all amounts of methanol are depending on import at present and the price is also expensive, mainly causing the overall leachate treatment cost to rise. Accordingly, methods of using waste terephthalic acid (TPA), and sugar manufacturing wastewater that can replace expensive methanol as an external carbon source for removing nitrogen included in leachate by using microorganisms have been studied. However, the waste TPA is in a solid form and in order to use this as an external carbon source, a separate storage and solution apparatuses are required, and in addition, when it is solved, an increase in pH through inputting a predetermined amount of sodium hydroxide (NaOH) is required. Also, since the sugar manufacturing wastewater is generated in a small volume, and therefore it is difficult to provide it stably. In addition, installation of a separate supplying facility is required and inputting of the sugar manufacturing wastewater causes color to increase. Meanwhile, in supernatant water of food waste, the concentration of organic materials is very high as illustrated in table 1, including a BOD of 100,000 mg/L, a COD of 150,000 mg/L, a T-N (total nitrogen) of 3,000 mg/L, and solid materials of 150,000 mg/L, and the degree of contamination degree is very high compared to the landfill leachate of household waste. Table 1 Comparison for characteristics of the quality of water between supernatant water of food waste and landfill leachate of household waste The supernatant water of food waste is analyzed as a mixture of supernatant water produced in a liquid storing pit, primary and secondary dewatering filtrates, and supernatant water produced in centrifugal concentrator. If the conventional biological treatment methods such as an anaerobic digestion method and an activated sludge method, which are used to treat livestock wastewater, excretions and leachate, are used as a method of treating the supernatant water of food waste, it is difficult to maintain appropriate breeding conditions for bacteria which is aerobic microorganisms and aerobic nitrification bacteria such as nitrosomonas and nitrobacter, as well as anaerobic digestion bacteria such as acid ferment bacteria and methanogens due to the excessive amount of inflowing load. Also, a problem that due to solid materials of up to 150,000 mg/L it is difficult to maintain the oxygen concentration of 3 ~ 5 mg/L required for treating aerobic microorganisms has been pointed out. In addition, the biological treatment such as anaerobic digestion and activated sludge, non-biodegradable COD of equal to or greater than 3,000 mg/L and color of equal to or over 1,000 degree remain, thereby requiring a separate chemicophysical treatment such as chemical condensation, oxidation, activated carbon adsorption, and reverse osmosis. Accordingly, it is very difficult to treat leachate produced from food waste solely with the conventional treatment method. As a result, most of the supernatant water of food waste is disposed at sea, and when the amount of the supernatant water is small, it is also treated on land by using a treatment method such as evaporation condensation. However, in relation to the disposal of the supernatant water at sea, contamination of the sea has been pointed out and regulations against it have been increasingly strengthened. Also, when the supernatant water is treated on land, it requires an excessive treatment cost of 200,000 ~ 300,000 Korean won per ton. SUMMARY OF THE INVENTION The present invention provides an improved method of mixing and purifying landfill leachate of household waste and supernatant water of food waste in which, by mixing and treating landfill leachate of household waste and supernatant water of food waste, the cost of using methanol occurring in a treatment process of leachate can be reduced, and sea contamination by disposal of supernatant water at sea can be prevented. More specifically, the supernatant water of food waste which is used as an organic carbon source replacing methanol in the present invention has a very low harmful material content such as heavy metals, while containing affluent organic materials that facilitate biological degradation and being in a liquid state similar to that of the leachate produced in a landfill of household waste. Accordingly, in a process for purifying landfill leachate of household waste, the supernatant water can be used directly as an externa! carbon source without requiring a separate preprocessing facility, thereby enabling a high efficiency of leachate treatment with a low cost. Accordingly, the present invention provides a method of mixing and purifying landfill leachate of household waste and supernatant water of food waste with a low cost and high efficiency, in which supernatant water of food waste which has high concentration organic materials, and being in a liquid state similar to that of landfill leachate of household waste, does not require a separate preprocessing facility, is directly utilized, thereby reducing a preprocessing cost, and at the same time, by using high concentration organic materials contained in the leachate instead of methanol as an external carbon source, the expensive treatment cost of leachate occurring when only the leachate is treated is greatly reduced. The present invention also provides a method of mixing and purifying landfill leachate of household waste and supernatant water of food waste in which, by enabling supernatant water of food waste, which is difficult to treat on land due to the high concentration and is disposed at seas because of high expense occurring when it is treated on land, to be treated on land with a low cost, sea contamination due to disposal of the supernatant water of food waste at sea can be solved in addition to cost reduction effect. According to an aspect of the present invention, there is provided a method of mixing and purifying landfill leachate of household waste and supernatant water of food waste, the method comprising: a mixing process for mixing and treating leachate produced in a landfill of household waste which is five years old or over in which the content of organic materials that can be degraded by microorganisms is very low (equal to or less than BOD, COD 500 mg/L) and supernatant water produced in a treatment process of food waste containing 150,000 mg/L or over COD, suspended solids, and nitrogen of 3,000 mg/L or over to a level appropriate for nitrogen treatment; an anaerobic digestion process for digestion of the mixed leachate and supernatant water to a level appropriate for denitrification and/or nitrification; a denitrification and/or nitrification process for removing nitrogen by using remaining organic materials through an anaerobic digestion process; a chemical coagulation process for clotting, precipitating and removing non-biodegradable organic materials remaining in the treated water from the denitrification and/or nitrification process, which are difficult to biologically degrade, by adding ferric sulfate which is a coagulation factor and an anion polymer coagulant which is a coagulating support agent; an oxidation coagulation process for removing remaining organic materials and color of the treated water from the chemical coagulation process, by adding ferric sulfate, hydrogen peroxide and powdered activated carbon at the same time. And, in the above purifying method, before the oxidation coagulation process, the chemical coagulation process using the ferric sulfate is executed, thereby effectively removing non-biodegradable organic materials and color, and by replacing ferrous sulfate, which is conventionally used as a catalyst in order to increase reaction of oxygenated water which is an oxidizing agent, with ferric sulfate, the treatment efficiency in the COD and color is maintained to be similar to that achieved when ferrous sulfate is used, while improving precipitation of sludge, thereby lowering the concentration of suspended solids in the treated water. Also, the suspended solids, COD, and color of the treated water can be greatly reduced by inputting powdered activated carbon. BRIEF DESCRIPTION OF THe ACCOMPANYING DRAWINGS FIG. 1 is a diagram illustrating a whole process of mixing and purifying landfill leachate of household waste and supernatant water of food waste according to an embodiment of the present invention; and FIG. 2 is a diagram illustrating a chemical coagulation process for removing non-biodegradable COD and color remaining in the treated water, which is treated in an anaerobic digestion process and a denitrification and/or nitrification process in sequence, and an oxidation coagulation process in which powdered activated carbon is input together. DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. The attached drawings illustrate embodiments of a method of purifying landfill leachate of household waste according to the present invention. FIG. 1 is a diagram illustrating a whole process, including a sump mixing process, an anaerobic digestion process, denitrification and/or nitrification process, a chemical coagulation process, and an oxidation coagulation process. As illustrated in FIG. 1, supernatant water produced in a process of treating food waste is made to be collected in a mixing sump (5) from supernatant water storing tank (1), and leachate produced in a landfill of household waste is made to be collected in the mixing sump (5) through an extraction pipe (3) and a transportation pipe (4), thereby performing a leachate mixing process mixing the collected water. That is, performance of the process for mixing the high concentration supernatant water of food waste and the leachate produced in the landfill of household waste which is five years old or over, and performance of anaerobic digestion process (6) can be referred to significant features of the present invention. In particular, the landfill leachate of household waste having a high content of non-biodegradable organic materials and nitrogen, and supernatant water of food waste which is relatively easier to biologically degrade and has a high content of organic materials and a low content of nitrogen, are mixed in a ratio of 1 to 0.8 ~ 1.2, and through a series of processes for anaerobic digestion treatment, the concentration ratio of organic materials to nitrogen (BOD)/NH4+ -N) is adjusted to be maintained at a ratio of 4.5 ~ 5.5 to 1. Accordingly, even without inputting an expensive external carbon source such as methanol that should be separately input when the denitrification and/or nitrification process (7) is performed by conventional method, the nitrogen treatment purpose through a denitrification and/or nitrification process can be achieved. The anaerobic denitrification and/or nitrification process will now be explained in more detail. The anaerobic digestion process (6) is a treatment process in which organic materials contained in the mixed water of the leachate and the supernatant water inflowing into a digestion tank are made to be digested and degraded by anaerobic microorganisms consisted of acid formers and methanogens under an anaerobic condition. The acid formers composed of Clostridium, peptococcus, anaerobus, etc, first degrade organic materials, thereby generating organic acid and alcohol such as butyric acid, lactic acid and acetic acid, and the generated organic acid and acetic acid are finally degraded into CH4 and CO2 by methanogens. In a more specific operating method of the anaerobic digestion tank, first, the supernatant water which is mixed with leachate in a ratio of 1 to 0.8 ~ 1.2 is input to the digestion tank and then, a digestion process is performed for 10 days at an intermediate digestion temperature range of 32 ~ 38°C. Through this process, 60 ~ 70% of organic materials contained in the supernatant water are removed, and organic nitrogen in the form of protein included in the supernatant water is changed to ammonia nitrogen (NH/ -N), thereby adjusting the density ratio of organic materials and nitrogen (BOD/ NH4+ -N) to be maintained at the ratio of 4.5 ~ 5.5 to 1 that is an appropriate level for denitrification and/or nitrification which is a backend process. The denitrification and/or nitrification process 7 is a process in which the leachate inflowing into a denitrification tank in the form of ammonia nitrogen is first inflowing into a nitrification tank installed at the back, thereby being oxidized to be nitrate nitrogen, and the nitrate nitrogen is returned to the denitrification tank installed in front, and discharged as nitrogen gas into the air by denitrifying bacteria, thereby being removed. In a biological nitrification process, ammonia nitrogen is oxidized to be nitrate nitrogen by nitrifying bacteria consisted of nitrosomonas and nitrobacter. - NH4+ + 1.502 -+ 2H+ + H2O + NO2 + 58 ~ 84 Kcal ? Nitrosomonas - NO2" + 0.5O2 ? NO3 + 15-21 Kcal ? Nitrobacter Also, the biological denitrification is a process in which NO2- and NO3- which are generated in the nitrification process are used as electron acceptors instead of oxygen in an anaerobic state and finally deoxidized to N2, N2O or NO, and discharged into the air. When a carbon source exists, denitrification reactions occur as follows: - NO3- + 1 /3 CH3OH ? NO2- + 1 /3 CO2 + 2/3H2O • NO2- + 1/2 CH3OH ? N2 + 1/2 CO2 + 1/2 H2O + OH- - NO3- + 5/6 CH3OH ? 1/2 N2 + 5/6CO2 + 7/6H2O + OH' Here, the amount of methanol required for reducing 1 g of NO3-N is approximately 1.9g(2.869gCOD). However, in the above process according to the present invention, without separate input of methanol, the mixed water of the supernatant water and the leachate which is treated in the previous anaerobic digestion process so that the concentration ratio of organic materials and nitrogen (BOD/NH/ -N) can be maintained to be a ratio of 4.5 ~ 5.5 to 1 is made to inflow. This is the main characteristic of this process, and through this process constructed as will be explained later, up to an average of 90% of nitrogen can be removed. More specifically, in this process, a denitrification and/or nitrification reactor is composed entirely of seven reactors, including two denitrification reactors (7-1) and five nitrification reactors (7-2). In the denitrification and/or nitrification reactor, a constant amount of the microorganism concentration of about 8,000 ~ 12,000 mg/L should always be maintained, and therefore recirculation from the nitrification reactor to the denitrification reactor is required. That is, recirculation of the microorganisms condensed in the precipitation reactor (7-3) is referred to as an external return, and the external return ratio is made to be 100 ~ 200% of the amount of water inflowing into the denitrification and/or nitrification reactor in order to prevent excessive surface water loading of the precipitation reactor. Recirculation performed from the nitrification reactor (7-2) to the denitrification reactor (7-1) is referred to as an internal return, and the internal return ratio is made to 700 ~ 900% of the amount of water inflowing into the denitrification and/or nitrification reactor by considering the installment capacity of pumps for return, and a maximum denitrification rate. The denitrification and/or nitrification process is the most important main treatment process in the present process, and in order to maintain a constant nitrification rate and a constant denitrification rate, an optimum state of microorganisms resident in the reactors should always be maintained. For this purpose, it is important to install a variety of microorganism breeding conditions to an appropriate level. First, the water temperature which is the most important in the breeding of the microorganisms living in the denitrification and/or nitrification reactor should be made to not exceed a maximum of 43°C in summer which is the limit for growing of denitrification and/or nitrification microorganisms, and should always be maintained at equal to or higher than a minimum of 25°C in winter. In order to maintain the appropriate water temperatures, the denitrification reactor and the nitrification reactor are installed as concrete structures, and on the top part of each of the structures, an opening part which can open and close by about 5% of a cover area is installed. When the water temperature rises in summer, the opening part is opened, and in winter the opening part is closed. In this way, the water temperature is adjusted so that an appropriate water temperature can always be maintained. Also, the depth of water of the reactor is made to be 6.5 ~ 7.5 m. The reactor is installed so that about 5 ~ 6 m of the depth is positioned underground and a height margin between the water surface and the cover is maintained to be in a range of 1.5 ~ 2.0 m or higher so that lowering of water temperature in winter can be prevented. In the denitrification reactor, by installing only a water mixer, an anaerobic condition of the concentration of dissolved oxygen (DO) of equal to or less than 0.5 mg/L is maintained, thereby facilitating reduction of nitrate nitrogen to nitrogen gas (N2 or N2O). In the nitrification reactor, sufficient oxygen is provided and in order to facilitate contact between microorganisms and pollutants a mechanical agitator and a diffuser for providing air are installed together so that the concentration of DO can be maintained at 3 ~ 5 mg/L. The treated water from the denitrification and/or nitrification process is made to sequentially inflow into a chemical coagulation process. The chemical coagulation process (8) is a process for treating recalcitrant organic materials remaining in the treated water from the denitrification and/or nitrification process, color and suspended solids. In order to maintain an optimum coagulation condition of reaction pH 5.0 ~ 5.5, sulfuric acid (H2SO4) is added, and at the same time ferric sulfate (Fe2(SO4)3) which is a coagulation factor is input in which the input amount is 300 ~ 350 mgFe3+/L relative to iron (HI) ion (Fe3+). Then, for about 15-25 minutes, a rapid stirring process at about 150 rpm is performed. In the treated water in which ferric sulfate which is the coagulation factor is mixed, 5 ~ 15 mg/L of an anion polymer coagulant which is a coagulating support agent is input and a slow stirring process at about 50 rpm is performed for about 6 ~ 14 minutes. The reaction water in which ferric sulfate and polymer coagulant are mixed is precipitated for 2 hours, and then, the precipitating sludge is dehydrated, and the top level water (treated water positioned on the top part) is made to inflow into the oxidation coagulation process in a natural flowing method. The oxidation coagulation process (9) is a process for removing non-biodegradable organic materials and color remaining in the treated water from the chemical coagulation process. By inputting ferric sulfate and hydrogen peroxide at the same time into the treated water from the chemical coagulation process, the reaction pH is made to be maintained in a range of 3 ~ 4, and for 3 ~ 4 hours, a rapid stirring process at about 150 rpm is performed. In this case, ferric sulfate is input with a concentration of 200 ~ 300 mgFe3+/L relative to iron(m) ion (Fe3+) and hydrogen peroxide is input with a concentration of 50 ~ 70 mgH2O2/L, thereby inducing oxidation. Also, 200 ~ 300 mg/L of powder activated carbon (F equal to or less than 0.1 mm) is input into the rapid reactor in which ferric sulfate and hydrogen peroxide are input, thereby increasing reaction and sludge precipitation. After the reaction process is performed, a neutralization process is performed by using sodium hydroxide (NaOH) in order to maintain a range of 6 ~ 7pH, and about 5-15 mg/L of a polymer coagulant (anion polymer) which is an anion cogulating support agent is input in the slow stirring process at about 50 rpm, in order to facilitate precipitation of sludge. In this way, by inputting powder activated carbon together, the suspended solids are reduced to 5 ~7 mg/L, which is a 50 ~ 70% decrease, COD is reduced to 50 ~ 60 mg/L which is a 50 ~ 60% decrease and color is reduced to 10 ~ 20 degrees, which is an 80 ~ 90 % decrease. By sufficiently increasing the oxidation coagulating reaction time which is about 30 minutes according to the conventional method, up to 3 ~ 4 hours, the negative effects (floating of precipitated sludge, increasing organic materials in the treated water, etc.) by remaining hydrogen peroxide occurring in the conventional oxidation coagulating reaction process is minimized. Through the present process, the precipitating sludge is dehydrated through a condensation process, and the top level water (treated water positioned on the top part) is discharged through a final water treatment tank. As illustrated in table 2 below, according to the result of treating wastewater which is obtained by mixing leachate and supernatant water of food waste containing high concentration non-biodegradable organic materials and nitrogen, by using the process of the present invention, the treatment efficiency of non-biodegradable organic materials is 99.5% and the treatment efficiency of nitrogen is 95.5%. Both figures are very high, indicating that the present invention has a high treatment efficiency compared to the conventional leachate purifying methods using methanol as an organic carbon source. The method of analyzing the BOD, CODcr and T-N is based on the Method of Environmental Pollution Process Experiment by the Ministry of Environment. When leachate of a household waste landfill and supernatant water of food waste which contains high concentration non-biodegradable organic materials and nitrogen and is mainly disposed at sea because of high cost for treatment on land, thereby becoming a major cause of sea contamination, are treated, the present invention mixes the two types of high concentration wastewater, thereby achieving a high efficiency treatment with a low cost. More specifically, since supernatant water of food waste is in a liquid state similar to that of leachate, and can be directly utilized as an external carbon source in a process for purifying leachate of a household waste landfill without a separate preprocessing facility, if the present invention is employed, the cost required for the preprocessing can be saved. Also, according to the conventional technology, methanol which is expensive is separately input as an organic carbon source in order to treat high concentration nitrogen. However, in the present invention, all the methanol is replaced by supernatant water of food waste, and the supernatant water is mixed with leachate and treated. In this way, the cost for treating leachate can be greatly reduced, thereby achieving a high treatment efficiency for leachate with a low cost. The reduction in the treatment cost achieved by the present invention is about 25,200 Korean won per ton when it is calculated as a net reduction cost, as illustrated in table 3 below. When the amount of supernatant water of food waste occurring within the country is considered (about 5,000 tons/day), the cost is estimated to be about 45 billion won per year. Also, according to the present invention, before the oxidation coagulation process, the chemical coagulation process using the ferric sulfate is executed, thereby effectively removing non-biodegradable organic materials and color, and by replacing ferrous sulfate, which is conventionally used as a catalyst in order to increase reaction of hydrogen peroxide which is an oxidizing agent, with ferric sulfate, precipitation of sludge is improved and the concentration of suspended solids in the treated water is lowered to 20 ~ 30 % (2~3 mg/L), and the treatment efficiency of the COD and color is 50 ~ 60 % similar to that achieved when ferrous sulfate is used. Also, by inputting powder activated carbon in the chemical coagulation process, the suspended solids, COD and color are greatly reduced. Furthermore, the present invention enables supernatant water of food waste, which has been disposed at sea because of high concentration and high cost preventing treatment on land, to be treated on land with a low cost, thereby reducing the cost of treatment and at the same time solving the sea contamination problem. We claim: 1. A method of mixing and purifying landfill leachate of household waste and supernatant water of food waste, the method comprising: a mixing process for collecting and mixing leachate produced in a landfill of household waste and supernatant water produced in food waste, in a ratio of 1 to 0.8 ~1.2; an anaerobic digestion process for removing high concentration non- biodegradable organics of the mixed waste water through digestion; a denitrification / nitrification process for removing nitrogen and non- biodegradable organic materials of the treated water from the anaerobic digestion process; a chemical coagulation process for condensing and precipitating remaining organic materials of the treated water from the denitrification / nitrification process; and an oxidation coagulation process for removing remaining organic materials and color of the treated water from the chemical coagulation process. 2. The method as claimed in claim 1, wherein in the anaerobic digestion process, by digesting the mixed waste water for ten days at a temperature range of 32 ~ 38°C which is an intermediate temperature range, the concentration ratio of organic materials and nitrogen (biochemical oxygen demand (BOD)/NH4* -N) is adjusted to be 4.5 ~ 5.5 to 1. 3. The method as claimed in claim 1, wherein in the denitrification / nitrification process, nitrogen is treated through denitrification reactions and nitrification reactions by denitrification / nitrification microorganisms by using organic materials included in the supernatant water of food waste as an external carbon source, while maintaining a denitrification / nitrification reactor in an amount of the microorganism concentration of 8,000 ~ 12,000 mg/L. 4. The method as claimed in claim 1, wherein in the chemical coagulation process, a rapid stirring process is performed by inputting sulfuric acid (H2SO4) which is a pH adjuster and ferric sulfate (Fe2(SO4)3) which is a chemical coagulation factor, and precipitation is performed through slow stirring by inputting a polymer coagulant which is a coagulating support agent. 5. The method as claimed in claim 1, wherein in the oxidation coagulation process, the treated water from the chemical coagulation process is rapidly stirred at 150 rpm for 3~4 hours by inputting ferric sulfate, hydrogen peroxide, and the pH adjuster (sulfuric acid) at the same time to maintain the reaction pH in a range of 3 ~ 4 pH, and through a neutralization process, an anion polymer coagulant which is a coagulating support agent is input, and then, by performing slow stirring, sludge is made to precipitate. 6. The method as claimed in claim 5, wherein in the oxidation coagulation process, powder activated carbon is input together in a rapid reactor into which ferric sulfate and hydrogen peroxide are input. A method of mixing and purifying landfill leachate of household waste and supernatant water of food waste, the method comprising: a mixing process for collecting and mixing leachate produced in a landfill of household waste and supernatant water produced in food waste, in a ratio of 1 to 0.8 - 1.2; an anaerobic digestion process for removing high concentration non-biodegradable organics of the mixed waste water through digestion;a denitrification / nitrification process for removing nitrogen and non-biodegradable organic materials of the treated water from the anaerobic digestion process; a chemical coagulation process for condensing and precipitating remaining organic materials of the treated water from the denitrification / nitrification process; and an oxidation coagulation process for removing remaining organic materials and color of the treated water from the chemical coagulation process.

Documents:

01562-kol-2007-abstract.pdf

01562-kol-2007-claims.pdf

01562-kol-2007-correspondence others.pdf

01562-kol-2007-description complete.pdf

01562-kol-2007-drawings.pdf

01562-kol-2007-form 1.pdf

01562-kol-2007-form 2.pdf

01562-kol-2007-form 3.pdf

01562-kol-2007-form 5.pdf

1562-KOL-2007-ABSTRACT 1.1.pdf

1562-KOL-2007-AMANDED CLAIMS.pdf

1562-KOL-2007-ASSIGNMENT 1.1.pdf

1562-KOL-2007-ASSIGNMENT.pdf

1562-KOL-2007-CORRESPONDENCE 1.2.pdf

1562-KOL-2007-CORRESPONDENCE OTHERS 1.1.pdf

1562-KOL-2007-DESCRIPTION (COMPLETE) 1.1.pdf

1562-KOL-2007-DRAWINGS 1.1.pdf

1562-KOL-2007-EXAMINATION REPORT.pdf

1562-KOL-2007-FORM 1-1.1.pdf

1562-KOL-2007-FORM 18 1.1.pdf

1562-kol-2007-form 18.pdf

1562-KOL-2007-FORM 2-1.1.pdf

1562-KOL-2007-FORM 3 1.2.pdf

1562-KOL-2007-FORM 3-1.1.pdf

1562-KOL-2007-FORM 5 1.1.pdf

1562-KOL-2007-GRANTED-ABSTRACT.pdf

1562-KOL-2007-GRANTED-CLAIMS.pdf

1562-KOL-2007-GRANTED-DESCRIPTION (COMPLETE).pdf

1562-KOL-2007-GRANTED-DRAWINGS.pdf

1562-KOL-2007-GRANTED-FORM 1.pdf

1562-KOL-2007-GRANTED-FORM 2.pdf

1562-KOL-2007-GRANTED-SPECIFICATION.pdf

1562-KOL-2007-OTHERS 1.1.pdf

1562-KOL-2007-OTHERS.pdf

1562-KOL-2007-PA 1.1.pdf

1562-KOL-2007-PA.pdf

1562-KOL-2007-PETITION UNDER RULE 137.pdf

1562-KOL-2007-PRIORITY DOCUMENT 1.1.pdf

1562-KOL-2007-PRIORITY DOCUMENT.pdf

1562-KOL-2007-REPLY TO EXAMINATION REPORT 1.1.pdf

1562-KOL-2007-REPLY TO EXAMINATION REPORT.pdf

1562-KOL-2007-TRANSLATED COPY OF PRIORITY DOCUMENT 1.1.pdf

1562-KOL-2007-TRANSLATED COPY OF PRIORITY DOCUMENT.pdf

abstract-01562-kol-2007.jpg