JP2004181409A

JP2004181409A - Method and apparatus for water sterilization and cleaning

Info

Publication number: JP2004181409A
Application number: JP2002353578A
Authority: JP
Inventors: Kazuo Abe; 一雄阿部; Toshio Ito; 敏雄伊藤; Toshiaki Murata; 逞詮村田; Masamichi Kikuchi; 真道菊池
Original assignee: Mitsui Engineering and Shipbuilding Co Ltd
Current assignee: Mitsui Engineering and Shipbuilding Co Ltd
Priority date: 2002-12-05
Filing date: 2002-12-05
Publication date: 2004-07-02

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water sterilization and cleaning apparatus which can safely remove iron and manganese from water, such as well water and underground water, containing a large amount of iron and manganese, and obtain perfectly sterilized treated water. <P>SOLUTION: The water sterilization and cleaning apparatus has a device for generating active oxygen by irradiating air with shortwave ultraviolet light in presence of a photocatalyst, an oxidation and filtration column for feeding the air treated by the above active oxygen generator into water to be treated, to coagulate and precipitate ions of iron and manganese in the water to be treated, and filtering the produced solid, a sterilization column for irradiating the water to be treated, discharged from the oxidation and filtration column with the shortwave ultraviolet light in presence of the photocatalyst to sterilize the water by generated hydroxy radicals, and a posttreatment device for further irradiating the water to be treated with longwave ultraviolet light to decompose excessive hydroxy radicals generated in the above process and returning the resultant water to the original water. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、水の殺菌浄化方法および装置に関し、特に鉄、マンガン等の金属イオンを多く含む水を光触媒の存在下に紫外線を照射して効率よく水の殺菌浄化を行う方法および装置に関する。
【０００２】
【従来の技術】
従来、紫外線による水の殺菌方法としては、１７０〜４００ｎｍの範囲の紫外線を照射し、被処理水中の被イオン性物質をイオン化し、該イオン化された物質を強酸性および強塩基性イオン交換樹脂により処理して除去する方法（特公昭５４−１９２２７号公報）、被処理水に波長１８０〜１９０ｎｍの紫外線（低圧紫外線ランプ）を照射し、酸化剤を用いることなく、有機物の分解、イオン化を行う方法（特開平１−１６４４８８号公報）などが知られている。しかしながらいずれの方法においても、被処理水中の有機物が分解、イオン化されて生成された物質はＣＯ_２まで分解されず、カルボン酸等の中間形態のまま存在するため、イオン交換樹脂を通してイオン化物質を除去する必要がある。このため、装置が複雑化し、高価になる等の欠点があった。このような従来の欠点を改善する方法として、本発明者等は、酸化チタン粒子を含む光触媒の存在下で水に紫外線を照射する水の浄化方法を提案し、特に被処理水をオゾンで殺菌処理した後、中波長の紫外線を照射し、さらに長波長の紫外線を照射して前記工程で生成したヒドロキシラジカル等を水に戻す水の浄化方法を提案した（国際公開公報ＷＯ００／７８６８０Ａ１）。しかし、この方法では、被処理水中に鉄、マンガン等の金属イオンを多量に含む場合、光照射によって生じた活性酸素により、前記金属イオンが酸化されて酸化物を析出し、紫外線照射の光源に付着したり、水中に浮遊して光照射を妨げ、処理効率を低下させるという問題を生じた。
【０００３】
【特許文献１】国際公開公報ＷＯ００／７８６８０Ａ１
【特許文献２】特開平１−１６４４８８号公報
【０００４】
【発明が解決しようとする課題】
本発明の課題は、井戸水や地下水等、鉄、マンガン等の金属イオンを多く含む水に対し、これらを除去して紫外線照射による析出物の発生を防止してその照射効率を高めると共に、完全に殺菌された浄化水を得ることができる水の殺菌浄化方法および装置を提供することにある。
【０００５】
【課題を解決するための手段】
上記課題を解決するため、本願により、特許請求される発明は以下の通りである。
（１）光触媒の存在下に空気に短中波長紫外線を照射して活性酸素を発生させる装置と、該活性酸素発生装置で処理された空気を被処理水中に曝気し、被処理水中の金属イオンを前記活性酸素により酸化析出させるとともに、生成した固形物を濾過する酸化濾過塔と、該酸化濾過塔を出た被処理水に、光触媒の存在下に中波長紫外線を照射し、生成したヒドロキシラジカルにより水の殺菌を行なう殺菌塔とを有することを特徴とする水の殺菌浄化装置。
【０００６】
（２）前記殺菌塔を出た処理水に長波長紫外線を照射し、前記殺菌塔で生成した過剰のヒドロキシラジカルを分解して元の水に戻す後処理装置をさらに有することを特徴とする（１）記載の装置。
【０００７】
（３）前記酸化濾過塔には、前記固形物を濾過する濾過層が設けられ、該濾過層の下部には、該濾過層を洗浄するための逆洗手段が設けられ、該逆洗手段は、前記殺菌塔からの処理水を供給する配管と、該配管に連結された噴射ノズルからなることを特徴とする（１）または（２）記載の装置。
【０００８】
（４）光触媒の存在下に空気に短中波長紫外線を照射して活性酸素を発生させる工程、該活性酸素を含有する空気を被処理水中に曝気し、被処理水中の金属イオンを前記活性酸素により酸化析出させるとともに、生成した固形物を濾過層を通過させて濾過する工程、および該濾過された被処理水に、光触媒の存在下に中波長紫外線を照射し、生成したヒドロキシラジカルにより水の殺菌を行なう工程と、前記濾過工程で、前記濾過層が汚染、または前記固形物の閉塞により、所定の圧力損失に達した時点で、前記水を殺菌する工程で処理された処理水により、該濾過層を逆洗する工程とを有することを特徴とする水の殺菌浄化方法。
【０００９】
（５）前記水を殺菌する工程で処理された処理水に長波長紫外線を照射し、前記工程で生成した過剰のヒドロキシラジカルを分解して元の水に戻す後処理工程をさらに有することを特徴とする（４）記載の方法。
【００１０】
本発明に用いる光触媒としては、酸化チタン粒子、または他の金属を担持した酸化チタン粒子が用いられる。酸化チタンとしては、一般によく知られている正方晶型（アナターゼ型およびルチル型）を用いることも出来るが、特に斜方晶型の酸化チタン、例えばブルッカイト（板チタン石）型の酸化チタンが好ましい。
【００１１】
本発明において、活性酸素発生装置に用いる紫外線ランプとしては、短中波長の紫外線、すなわち、１８５ｎｍと２５４ｎｍの両波長にピーク強度を有する紫外線ランプ、例えば岡谷電機株式会社製のＺＬ−４０紫外線ランプが好適に用いられる。このように短中波長紫外線ランプを用いることにより、特にオゾン発生装置等を用いることなく、簡単な装置で効率よく活性酸素を含有する空気を得ることができる。また中波長紫外線ランプとしては、ＵＶＢランプ（基本的に２５４ｎｍのみにピーク強度を有する）が用いられるが、前記の短中波長紫外線ランプを使用してもよい。中波長紫外線の照射により主に水中の殺菌が行われる。さらに長波長紫外線を照射する紫外線ランプとしては、基本的に３６５ｎｍにピーク強度を有するＵＶＣランプ（ブラックライト等）が用いられる。長波長紫外線の照射により、排水中に残留するヒドロキシラジカル、オゾン等の活性酸素種が無害化される。
【００１２】
【発明の実施の形態】
以下、本発明を図面に示す実施例によりさらに詳細に説明する。
図１は、本発明装置の概要を示す説明図である。この装置は、光触媒３を塗布した容器内に短中波長紫外線を照射する紫外線ランプ５を有する活性酸素発生装置１と、該活性酸素発生装置１で処理された空気を被処理水中に曝し、水中の鉄、マンガン等の金属イオンを除去するための酸化濾過塔１０と、該酸化濾過塔１０を出た被処理水に、光触媒の存在下に紫外線ランプ３３から中波長紫外線を照射し、生成したヒドロキシラジカルにより水の殺菌を行う殺菌装置３１と、該殺菌装置で処理された水にさらに紫外線ランプ４１（例えばブラックライト）から長波長紫外線を照射し、前記工程で生成した過剰なヒドロキシラジカルを分解し、無害な水に戻す後処理装置３７とから主として構成される。後処理装置３７は、活性酸素を含有する水をそのまま使用する場合は不要である。活性酸素発生装置１は、容器内の側壁に光触媒３（例えばブルッカイト型の酸化チタン）が塗布されている。
【００１３】
空気７はブロアにより活性酸素発生装置１の下方から入り、光触媒３の存在下に短中波長紫外線照射によりオゾン、スーパーオキシド等の活性酸素種を発生した後、配管９により抜き出され、酸化濾過塔１０に供給されて、水の殺菌、浄化処理に用いられる。酸化濾過塔１０には、上部および下部にそれぞれ酸化ゾーン（空塔部）１１および濾過層１３が設けられ、塔頂部に原水１９の散布ノズル２１が設けられている。酸化ゾーン１１の下部には配管９からの活性酸素を含む空気の噴射ノズル１５が上向きに設けられ、また濾過層１３の直下には逆洗用の噴射ノズル１７が上向きに設けられている。濾過層１３には濾過材、例えば砂等が充填されている。濾過層１３には、いわゆる除鉄、除マンガン剤、例えば製鉄所の鉄スカムを固化した充填材を用いてもよい。濾過層１３を流下した水は塔底から抜き出され、配管３５およびポンプ３６により、殺菌装置３１に導入される。殺菌装置３１は、筒状容器内の側壁に前述の光触媒３を塗布し、中央部に中波長紫外線を照射するための紫外線ランプ３３を挿入したものである。紫外線ランプ３３は、２５４ｎｍにピーク強度を有する中波長紫外線ランプが用いられるが、１８５ｎｍと２５４ｎｍの両方にピーク強度を有する短中波長紫外線ランプでもよい。殺菌装置３１を出た処理水を無害化するための後処理装置３７は筒状容器内に長波長紫外線を照射するための紫外線ランプ４１（例えば市販のＵＶＣランプ、ブラックライト等）が設けられたものである。
【００１４】
殺菌装置３１に供給される処理水中には、常にヒドロキシラジカル等の活性酸素種が存在することが好ましく、このため酸化濾過塔１０には該塔で消化する以上の過剰量の活性酸素種を供給するように制御することが望ましい。なお、殺菌装置３１の活性酸素種の量が不足する場合には、配管９を分岐した配管４８のバルブから殺菌装置３１への排水供給配管３５に活性酸素種を含む空気を直接導入してもよい。
【００１５】
上記装置において、配管９から導入された、オゾン、スーパーオキシド等の活性酸素種を含む空気は、酸化濾過塔１０の酸化ゾーン１１の下方から噴射ノズル１５により噴射され、ここで散布ノズル２１から散布される原水１９と接触し、酸化ゾーン１１を流下する間に被処理水に含まれる鉄イオン、マンガンイオン等の金属イオンが酸化され、鉄酸化物、マンガン酸化物等の析出物を生成させる。これらの固形物を含む処理水は、酸化濾過塔１０の下部の濾過層１３で捕集、除去された後、塔底部から抜き出され、配管３５を通して殺菌装置３１内に導入され、ここで水中に残存する溶存活性酸素種を利用し、光触媒の存在下に中波長紫外線の照射によってヒドロキシラジカルを生成させ、排水の殺菌処理が行われる。この場合、排水中に残留する活性酸素種が少なすぎる場合には、配管４８のバルブを調整して活性酸素種を含有する空気を補充する。殺菌装置３１を出た処理水は次に配管３９を通って後処理装置３７に導入され、ここで長波長紫外線照射により水中の残存ヒドロキシラジカルやオゾンが無害化処理され、浄化水４３として系外に排出される。濾過層１３の圧力損失が高くなった場合、殺菌装置３１で殺菌処理された水を配管４５を通して酸化濾過塔１０に戻し、噴射ノズル１７から濾過層１３に向けて噴射し、濾過層１３を洗浄する。このように殺菌水を濾過層１３の逆洗用として用いることにより、該濾過層における菌の繁殖を防ぎ、濾過層の目詰まりを防止することができる。
【００１６】
以下、本発明の具体的実施例を述べる。
図１に示した装置として下記仕様のものを用い、下記の条件で水処理を行った。

上記のように原水を処理した結果、浄化水４３の水質は、Ｍｎ^２＋０．００７ｍｇ／ｌ、Ｆｅ^２＋０．１ｍｇ／ｌ、一般細菌０ＣＦＵ／ｍｌに浄化された。
【００１７】
【発明の効果】
請求項１〜３記載の発明によれば、鉄、マンガン等の金属イオンを含む被処理水からこれらの金属イオンを効率よく除去し、紫外線の照射効率を高めると共に、原虫類、真菌類、細菌、ウィルス等の細菌を除去した殺菌浄化水を得ることができる。
請求項４および５記載の発明によれば、上記の効果に加え、汚染した濾過層を系内で生成した殺菌水で洗浄し、菌の繁殖による汚染を防止することができる。
【図面の簡単な説明】
【図１】本発明の水の殺菌浄化装置の一実施例を示す説明図。
【符号の説明】
１…活性酸素発生装置、３…光触媒、５…紫外線ランプ、７…空気、９…配管、１０…酸化濾過塔、１１…酸化ゾーン、１３…濾過層、１５、１７…噴射ノズル、１９…原水、２１…散布ノズル、３０…殺菌後処理装置、３１…殺菌装置、３３…紫外線ランプ、３５…配管、３６…ポンプ、３７…後処理装置、３９…配管、４１…紫外線ランプ、４３…浄化水、４５…配管。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method and an apparatus for disinfecting and purifying water, and more particularly to a method and an apparatus for disinfecting and purifying water efficiently by irradiating water containing a large amount of metal ions such as iron and manganese with ultraviolet rays in the presence of a photocatalyst.
[0002]
[Prior art]
Conventionally, as a method of disinfecting water with ultraviolet rays, an ultraviolet ray in a range of 170 to 400 nm is irradiated to ionize the ionizable substance in the water to be treated, and the ionized substance is ionized with a strongly acidic and strongly basic ion exchange resin. A method of treating and removing (Japanese Patent Publication No. 54-19227), a method of irradiating treated water with ultraviolet rays (low-pressure ultraviolet lamp) having a wavelength of 180 to 190 nm, and decomposing and ionizing organic substances without using an oxidizing agent. (JP-A-1-164488) is known. However, in any method, the organic matter in the water to be treated is decomposed and ionized, and the generated substance is not decomposed to CO ₂ and remains in an intermediate form such as carboxylic acid. Therefore, the ionized substance is removed through the ion exchange resin. There is a need to. For this reason, there are drawbacks such as the device becoming complicated and expensive. As a method for improving such a conventional drawback, the present inventors have proposed a water purification method in which water is irradiated with ultraviolet rays in the presence of a photocatalyst containing titanium oxide particles, and in particular, sterilize treated water with ozone. After the treatment, a method of purifying water by irradiating ultraviolet rays of a medium wavelength and further irradiating ultraviolet rays of a longer wavelength to return hydroxyl radicals and the like generated in the above step to water was proposed (WO 00/78680 A1). However, in this method, when the water to be treated contains a large amount of metal ions such as iron and manganese, the metal ions are oxidized by active oxygen generated by light irradiation to precipitate oxides, which are used as a light source for ultraviolet irradiation. There is a problem that it adheres or floats in water, hinders light irradiation, and reduces treatment efficiency.
[0003]
[Patent Document 1] International Publication WO00 / 78680A1
[Patent Document 2] Japanese Patent Application Laid-Open No. 1-164488
[Problems to be solved by the invention]
The object of the present invention is to improve the irradiation efficiency by preventing the generation of precipitates due to ultraviolet irradiation by removing these to water containing a large amount of metal ions such as iron and manganese, such as well water and groundwater, and completely improving the irradiation efficiency. An object of the present invention is to provide a method and an apparatus for sterilizing and purifying water capable of obtaining sterilized purified water.
[0005]
[Means for Solving the Problems]
The invention claimed by the present application to solve the above problems is as follows.
(1) A device for generating active oxygen by irradiating air with short- and medium-wavelength ultraviolet rays in the presence of a photocatalyst, and aerating the air treated by the active oxygen generator into the water to be treated to form metal ions in the water to be treated. Is oxidized and precipitated by the active oxygen, and an oxidative filtration tower for filtering the generated solid matter, and water to be treated that has exited the oxidative filtration tower is irradiated with medium-wavelength ultraviolet rays in the presence of a photocatalyst, and the generated hydroxy radical And a disinfection tower for disinfection of water by the method.
[0006]
(2) It is characterized by further comprising a post-treatment device that irradiates the treated water that has exited the sterilization tower with long-wavelength ultraviolet rays to decompose excess hydroxyl radicals generated in the sterilization tower and restore the original water. The device according to 1).
[0007]
(3) The oxidative filtration tower is provided with a filtration layer for filtering the solid matter, and a backwashing means for washing the filtration layer is provided below the filtration layer. The apparatus according to (1) or (2), comprising a pipe for supplying treated water from the sterilizing tower, and an injection nozzle connected to the pipe.
[0008]
(4) a step of irradiating air with short to medium wavelength ultraviolet rays in the presence of a photocatalyst to generate active oxygen, aerating the air containing the active oxygen into the water to be treated, and converting the metal ions in the water to be treated into the active oxygen; And oxidizing and precipitating by the step of filtering the generated solid through a filtration layer, and irradiating the filtered water to be treated with medium-wavelength ultraviolet rays in the presence of a photocatalyst, and generating hydroxyl radicals to form water. In the step of performing sterilization, in the filtration step, when the filtration layer reaches a predetermined pressure loss due to contamination or clogging of the solid, the treated water treated in the step of sterilizing the water is used. Backwashing the filtration layer.
[0009]
(5) The method further comprises a post-treatment step of irradiating the treated water treated in the step of disinfecting the water with long-wavelength ultraviolet rays to decompose excess hydroxy radicals generated in the step and returning it to the original water. (4).
[0010]
As the photocatalyst used in the present invention, titanium oxide particles or titanium oxide particles supporting another metal are used. As the titanium oxide, a generally well-known tetragonal type (anatase type and rutile type) can also be used, and particularly, an orthorhombic type titanium oxide, for example, a brookite (sheet titanium stone) type titanium oxide is preferable. .
[0011]
In the present invention, as the ultraviolet lamp used in the active oxygen generator, short-medium wavelength ultraviolet light, that is, an ultraviolet lamp having peak intensity at both wavelengths of 185 nm and 254 nm, for example, a ZL-40 ultraviolet lamp manufactured by Okaya Electric Co., Ltd. It is preferably used. By using the short-medium-wavelength ultraviolet lamp, air containing active oxygen can be efficiently obtained with a simple device without using an ozone generator or the like. A UVB lamp (basically having a peak intensity only at 254 nm) is used as the medium-wavelength ultraviolet lamp, but the above-mentioned short-medium-wavelength ultraviolet lamp may be used. Sterilization in water is mainly performed by irradiation with medium-wavelength ultraviolet rays. Further, as an ultraviolet lamp for irradiating long-wavelength ultraviolet light, a UVC lamp (black light or the like) basically having a peak intensity at 365 nm is used. By irradiation with long-wavelength ultraviolet rays, active oxygen species such as hydroxy radicals and ozone remaining in the wastewater are rendered harmless.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in more detail with reference to the drawings.
FIG. 1 is an explanatory view showing the outline of the device of the present invention. This apparatus includes an active oxygen generator 1 having an ultraviolet lamp 5 for irradiating short-medium wavelength ultraviolet light into a container coated with a photocatalyst 3, and exposing air treated by the active oxygen generator 1 to water to be treated. Oxidation filtration tower 10 for removing metal ions such as iron and manganese, and water to be treated that has exited the oxidation filtration tower 10 is irradiated with medium-wavelength ultraviolet rays from an ultraviolet lamp 33 in the presence of a photocatalyst to produce water. A sterilizer 31 for sterilizing water with hydroxyl radicals, and further irradiates water treated by the sterilizer with long-wavelength ultraviolet rays from an ultraviolet lamp 41 (eg, black light) to decompose excess hydroxyl radicals generated in the above step. And a post-processing device 37 for returning to harmless water. The post-treatment device 37 is unnecessary when water containing active oxygen is used as it is. In the active oxygen generator 1, a photocatalyst 3 (for example, brookite type titanium oxide) is applied to a side wall in a container.
[0013]
The air 7 enters from below the active oxygen generator 1 by a blower, generates active oxygen species such as ozone and superoxide by short- and medium-wavelength ultraviolet irradiation in the presence of the photocatalyst 3, is extracted through a pipe 9, and is oxidized and filtered. The water is supplied to the tower 10 and used for sterilizing and purifying water. The oxidation filtration tower 10 is provided with an oxidation zone (empty tower) 11 and a filtration layer 13 at the upper and lower parts, respectively, and a spray nozzle 21 for raw water 19 at the top of the tower. An injection nozzle 15 for air containing active oxygen from the pipe 9 is provided upward at a lower portion of the oxidation zone 11, and a spray nozzle 17 for backwash is provided directly below the filtration layer 13. The filter layer 13 is filled with a filter material, for example, sand or the like. The filtration layer 13 may use a so-called iron removal or manganese removal agent, for example, a filler obtained by solidifying iron scum of an ironworks. The water that has flowed down the filtration layer 13 is extracted from the bottom of the tower, and introduced into the sterilizer 31 by the pipe 35 and the pump 36. The sterilizing device 31 is a device in which the above-described photocatalyst 3 is applied to a side wall in a cylindrical container, and an ultraviolet lamp 33 for irradiating medium-wavelength ultraviolet light is inserted in a central portion. As the ultraviolet lamp 33, a medium-wavelength ultraviolet lamp having a peak intensity at 254 nm is used, but a short-medium-wavelength ultraviolet lamp having peak intensity at both 185 nm and 254 nm may be used. The post-treatment device 37 for detoxifying the treated water that has exited the sterilization device 31 is provided with an ultraviolet lamp 41 (for example, a commercially available UVC lamp, black light, or the like) for irradiating long-wavelength ultraviolet light in a cylindrical container. Things.
[0014]
It is preferable that active oxygen species such as hydroxy radicals always be present in the treated water supplied to the sterilizer 31. Therefore, an excessive amount of active oxygen species that is digested in the oxidative filtration tower 10 is supplied to the oxidation filtration tower 10. It is desirable to control so that When the amount of the active oxygen species in the sterilizer 31 is insufficient, the air containing the active oxygen species may be directly introduced into the drainage supply pipe 35 to the sterilizer 31 from the valve of the pipe 48 branched from the pipe 9. Good.
[0015]
In the above apparatus, air containing active oxygen species such as ozone and superoxide introduced from the pipe 9 is jetted from below the oxidation zone 11 of the oxidation filtration tower 10 by the injection nozzle 15, where it is sprayed from the spray nozzle 21. The metal ions such as iron ions and manganese ions contained in the water to be treated are oxidized while contacting the raw water 19 to be discharged and flowing down the oxidation zone 11 to generate precipitates such as iron oxide and manganese oxide. The treated water containing these solids is collected and removed by the filtration layer 13 at the lower part of the oxidative filtration tower 10, extracted from the bottom of the tower, introduced into the sterilization apparatus 31 through the pipe 35, and then treated with the water. The residual active oxygen species remaining in the wastewater are used to generate hydroxyl radicals by irradiation with medium-wavelength ultraviolet rays in the presence of a photocatalyst, and the wastewater is sterilized. In this case, when the amount of the active oxygen species remaining in the wastewater is too small, the valve containing the piping 48 is adjusted to replenish the air containing the active oxygen species. The treated water that has exited the sterilizing device 31 is then introduced into a post-processing device 37 through a pipe 39, where the remaining hydroxyl radicals and ozone in the water are detoxified by long-wavelength ultraviolet irradiation. Is discharged. When the pressure loss of the filtration layer 13 becomes high, the water sterilized by the sterilization device 31 is returned to the oxidation filtration tower 10 through the pipe 45, and is injected from the injection nozzle 17 toward the filtration layer 13 to wash the filtration layer 13. I do. By using the sterilized water for backwashing the filtration layer 13 as described above, it is possible to prevent the growth of bacteria in the filtration layer and prevent the filtration layer from being clogged.
[0016]
Hereinafter, specific examples of the present invention will be described.
Water treatment was performed under the following conditions using the apparatus shown in FIG. 1 having the following specifications.

As a result of treating the raw water as described above, the water quality of the purified water 43 was purified to Mn ²⁺ 0.007 mg / l, Fe ²⁺ 0.1 mg / l, and general bacteria 0 CFU / ml.
[0017]
【The invention's effect】
According to the first to third aspects of the present invention, these metal ions are efficiently removed from the water to be treated containing metal ions such as iron and manganese, and the irradiation efficiency of ultraviolet rays is increased, as well as protozoa, fungi, and bacteria. Thus, sterilized purified water from which bacteria such as viruses have been removed can be obtained.
According to the fourth and fifth aspects of the present invention, in addition to the above-described effects, the contaminated filtration layer can be washed with sterilized water generated in the system to prevent contamination due to propagation of bacteria.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing one embodiment of a water sterilization and purification apparatus of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Active oxygen generator, 3 ... Photocatalyst, 5 ... Ultraviolet lamp, 7 ... Air, 9 ... Piping, 10 ... Oxidation filtration tower, 11 ... Oxidation zone, 13 ... Filtration layer, 15, 17 ... Injection nozzle, 19 ... Raw water , 21 ... spray nozzle, 30 ... sterilization post-treatment device, 31 ... sterilization device, 33 ... ultraviolet lamp, 35 ... piping, 36 ... pump, 37 ... post-processing device, 39 ... piping, 41 ... ultraviolet lamp, 43 ... purified water , 45 ... piping.

Claims

A device for irradiating air with short- and medium-wavelength ultraviolet rays in the presence of a photocatalyst to generate active oxygen, and aerating the air processed by the active oxygen generator into the water to be treated, thereby activating the metal ions in the water to be treated Oxidation and precipitation by oxygen, and an oxidation filtration tower for filtering the generated solid matter, and irradiating the water to be treated that has exited the oxidation filtration tower with medium-wavelength ultraviolet rays in the presence of a photocatalyst, A water sterilization / purification device comprising a sterilization tower for performing sterilization.

2. The post-treatment device according to claim 1, further comprising: irradiating the treated water that has exited the sterilization tower with a long-wavelength ultraviolet ray to decompose excess hydroxyl radicals generated in the sterilization tower and returning the water to the original water. Equipment.

The oxidative filtration tower is provided with a filtration layer for filtering the solid matter, and a lower part of the filtration layer is provided with a back washing means for washing the filtration layer, and the back washing means is provided with the sterilizer. 3. The apparatus according to claim 1, comprising a pipe for supplying treated water from the tower, and an injection nozzle connected to the pipe.

Irradiating air with short to medium wavelength ultraviolet light in the presence of a photocatalyst to generate active oxygen, aerating the air containing the active oxygen into the water to be treated, and oxidizing and precipitating metal ions in the water to be treated with the active oxygen; And a step of filtering the generated solid through a filtration layer, and irradiating the filtered water to be treated with medium-wavelength ultraviolet rays in the presence of a photocatalyst to sterilize the water with the generated hydroxyl radical. In the filtration step, the filtration layer is contaminated, or the solid matter is blocked, and when a predetermined pressure loss is reached, the filtration layer is treated with the treated water that has been treated in the step of sterilizing the water. Backwashing the water.

The method according to claim 1, further comprising a post-treatment step of irradiating the treated water treated in the step of disinfecting the water with long-wavelength ultraviolet rays and decomposing excess hydroxy radicals generated in the step to return to the original water. Item 5. The method according to Item 4.