JP2005040748A - Sealed sewage treatment tank made of sheet - Google Patents

Sealed sewage treatment tank made of sheet Download PDF

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Publication number
JP2005040748A
JP2005040748A JP2003279526A JP2003279526A JP2005040748A JP 2005040748 A JP2005040748 A JP 2005040748A JP 2003279526 A JP2003279526 A JP 2003279526A JP 2003279526 A JP2003279526 A JP 2003279526A JP 2005040748 A JP2005040748 A JP 2005040748A
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sheet
tank
treatment tank
sewage treatment
roof
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JP4324427B2 (en
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Yutaka Nakai
裕 中井
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SENPO KENSETSU KK
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SENPO KENSETSU KK
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W10/00—Technologies for wastewater treatment
    • Y02W10/30—Wastewater or sewage treatment systems using renewable energies
    • Y02W10/37—Wastewater or sewage treatment systems using renewable energies using solar energy

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  • Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet type sealed treatment tank usable in anaerobic treatment of sewage. <P>SOLUTION: A rectangular reservoir-like pit is dug in the ground, and impermeable sheet 1 is lined over the whole inner surface of the pit to form a sewage treatment tank 2. The sheet 1 is made of rubber with seams thermally welded by a welder. A roof sheet 5 is attached to cover an upper part of the tank 2, using the same material as the sheet 1. Buoyancy bodies 6 are attached to a rear surface of the roof sheet. The buoyancy body is a block made of foamed styrene, and the bodies are attached to whole of the surface at intervals. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

この発明は、シートで作った密閉汚水処理槽に関する。   The present invention relates to a sealed sewage treatment tank made of a sheet.

バクテリアを使った汚水処理では、汚水を溜めておく処理槽はコンクリートで作るのが普通である。コンクリート製の処理槽は強度が高く信頼性が高いが、建設費が高いのが欠点である。牧場の家畜小屋の汚水処理を行うような簡易の処理施設では、コンクリート製の処理槽の建設はコスト的に負担が大きい。そこで、地面に穴を掘り、その内面を遮水シートで覆い、上に簡単な屋根を設けた簡易処理槽が従来使われている。このようなものでも、汚水が地中に染み込むのを防止でき、また、何より建設費が安く工期も短い。   In the sewage treatment using bacteria, the treatment tank for storing the sewage is usually made of concrete. A concrete treatment tank is strong and reliable, but its construction cost is high. In a simple treatment facility that treats sewage in a livestock shed on a ranch, the construction of a concrete treatment tank is costly. Therefore, a simple treatment tank is conventionally used in which a hole is dug in the ground, its inner surface is covered with a water shielding sheet, and a simple roof is provided thereon. Even such a thing can prevent sewage from seeping into the ground, and the construction cost is cheaper and the construction period is shorter than anything else.

しかし、このような処理槽は上部が開放しているので、好気処理には使えても嫌気処理には使用できない。嫌気処理を行うために密閉槽にするためには、槽の上もルーフシートで覆う必要がある。しかし、使用中、降った雨や雪がルーフシートの上に溜まり、その重さでシートが裂けてしまうおそれがある。   However, since such a treatment tank is open at the top, it can be used for anaerobic treatment but not for anaerobic treatment. In order to make a sealed tank for anaerobic treatment, it is necessary to cover the top of the tank with a roof sheet. However, during use, rain or snow that has fallen may accumulate on the roof sheet, and the weight may cause the sheet to tear.

この発明は、汚水の嫌気処理に使うことができる、密閉されたシート式の処理槽を提供することを課題とする。   An object of the present invention is to provide a sealed sheet-type treatment tank that can be used for anaerobic treatment of sewage.

この発明のシート式汚水処理槽は、地面に穴を掘ってその内面を遮水シートで覆うと共に、遮水シートに縁部を接合したルーフシートで該穴の上面を覆って、密閉式の汚水処理槽を形成し、槽内に貯留した汚水中の有機物がバクテリアの働きで分解し、そのとき発生するガスで槽内を大気圧以上の圧力に保持して、ルーフシートを浮揚支持するようにしたものである（請求項１）。     The sheet-type sewage treatment tank according to the present invention digs a hole in the ground and covers its inner surface with a water-impervious sheet, and covers the upper surface of the hole with a roof sheet in which an edge is joined to the water-impervious sheet. Forming a treatment tank, organic matter in the sewage stored in the tank is decomposed by the action of bacteria, and the roof sheet is floated and supported by holding the inside of the tank at a pressure higher than atmospheric pressure with the gas generated at that time (Claim 1).

嫌気処理槽ではバクテリアの働きでメタン、炭酸ガス等のガスが発生するので、この発明ではそれらのガスを逃さないようにして槽内を大気圧以上に保持し、その圧力でルーフシートを浮揚させ、ルーフシートが槽の上に垂れ下がらないようにすることができる。このため、ルーフシートの上に雨や雪がたまりにくく、したがって、雨や雪の重みがかからず、破損しにくいという効果がある。また、コンクリートは使わずにシートで作るので、建設費が安く、工期も短くて済む。   In an anaerobic treatment tank, bacteria and other gases generate gases such as methane and carbon dioxide. In this invention, the inside of the tank is maintained at atmospheric pressure or higher so that these gases are not lost, and the roof sheet is levitated at that pressure. The roof sheet can be prevented from hanging down on the tank. For this reason, rain and snow are unlikely to accumulate on the roof sheet, and therefore, there is an effect that the weight of rain and snow is not applied and damage is difficult. In addition, since concrete is made of sheets without using it, construction costs are low and the construction period is short.

使用開始時や厳寒時など、バクテリアの働きが活発でなく、所望の槽内圧力が得られないときは、ルーフシートが垂れ下がってしまうおそれがある。これを防止するため、槽内に空気を圧入するための手段、例えばコンプレッサ等を設けることが好ましい（請求項２）。   When the use of bacteria is not active, such as at the start of use or during extreme cold, and the desired tank pressure cannot be obtained, the roof sheet may hang down. In order to prevent this, it is preferable to provide means for press-fitting air into the tank, such as a compressor.

槽内圧力が過大になると、シートが破裂するおそれがあるので、これを防止するため、圧力逃し弁を設けることが好ましい（請求項３）。   If the pressure inside the tank becomes excessive, the sheet may be ruptured. In order to prevent this, it is preferable to provide a pressure relief valve (claim 3).

ルーフシートを下からの圧力で浮揚するだけでなく、ルーフシートの裏面に、槽内汚水上に浮く浮力体を取り付けるようにしてもよい（請求項４）。こうすれば、浮力体がルーフシートを下から支えるので、ルーフシートの垂れ下がりが過大になるのを防止することができる。   In addition to levitation of the roof sheet with pressure from below, a buoyancy body that floats on the sewage in the tank may be attached to the back surface of the roof sheet. In this way, the buoyancy body supports the roof sheet from below, so that it is possible to prevent the drooping of the roof sheet from becoming excessive.

なお、このような浮力体は、施工時にも有用である。槽の上にルーフシートを取り付けるとき、ルーフシートが自重で中央が垂れ下がってしまい、縁部を遮水シートに接合するのが難しい。ルーフシートの裏に浮力体があれば、浮力体が槽内の汚水上に浮かんでルーフシートの垂れ下がりを小さくでき、容易に接合ができる。   Such a buoyancy body is also useful during construction. When the roof sheet is mounted on the tank, the center of the roof sheet hangs down due to its own weight, and it is difficult to join the edge to the waterproof sheet. If there is a buoyant body on the back of the roof sheet, the buoyant body floats on the sewage in the tank, so that the sag of the roof sheet can be reduced and can be joined easily.

図１および図２に示すように、地面に長方形の溜池状の穴を掘り、その内面全面に遮水シート１を張って汚水処理槽２を形成する。槽の大きさは、縦20m、横5m、深さ2.5mほどである。遮水シート１はゴム製であり、廃棄物処分場で汚水が地下に染み出さないように敷設するのと同じものある。シート厚は2mmである。シートの継ぎ目は融着機を用いて熱融着する。尖った石などに当たって破けないよう、遮水シートの下には保護マット（厚さ10mmの不織布）を敷く。   As shown in FIG. 1 and FIG. 2, a rectangular basin-like hole is dug in the ground, and a water shielding sheet 1 is stretched over the entire inner surface to form a sewage treatment tank 2. The size of the tank is about 20m long, 5m wide, and 2.5m deep. The water-impervious sheet 1 is made of rubber, and is the same as laying in a waste disposal site so that sewage does not bleed into the basement. The sheet thickness is 2 mm. The seam of the sheet is heat-sealed using a fusing machine. Place a protective mat (non-woven fabric with a thickness of 10 mm) under the waterproof sheet so that it does not break when hit by sharp stones.

次いで、汚水処理槽２の上部を覆うためにルーフシート５を取り付ける。シートの材料は遮水シート１と同じものである。ルーフシートの裏側には浮力体６を取り付ける。浮力体は発泡スチロール製のブロックであり、これを間隔を設け全面に取り付ける。   Next, the roof sheet 5 is attached to cover the upper part of the sewage treatment tank 2. The material of the sheet is the same as that of the water shielding sheet 1. The buoyancy body 6 is attached to the back side of the roof sheet. The buoyancy body is a block made of polystyrene foam, which is attached to the entire surface with a gap.

ルーフシートの取付工事では、処理槽に水を張り、裏に浮力体を取り付けたルーフシートを処理槽の一端に置き、これを引張るようにして処理槽の上にずらしていく。このとき、図１に鎖線で示すように、浮力体６が水の上に浮いてルーフシート５を支えるので、ルーフシートがひどく垂れ下がることがない。こうして、ルーフシートの縁に土嚢を置いて仮止めし、遮水シート１と熱融着する   In the installation work of the roof sheet, water is applied to the treatment tank and a roof sheet with a buoyant body attached to the back is placed on one end of the treatment tank, and this is pulled over the treatment tank. At this time, as indicated by a chain line in FIG. 1, the buoyancy body 6 floats on the water and supports the roof sheet 5, so that the roof sheet does not drastically hang down. Thus, a sandbag is placed on the edge of the roof sheet, temporarily fixed, and heat-sealed with the water shielding sheet 1.

図３は融着部（図１に符号Ａで示す）の拡大断面図である。遮水シート１の上にルーフシート５を重ね、さらにその下にもう一枚シート７（周辺シート）を重ね、一体に熱融着する。周辺シート７はＵ字排水溝９の下に敷き込み、ルーフシートの上に降った雨水が直にＵ字排水溝９に流れ込むようにする。   FIG. 3 is an enlarged cross-sectional view of the fused portion (indicated by reference numeral A in FIG. 1). The roof sheet 5 is overlaid on the water-impervious sheet 1, and another sheet 7 (peripheral sheet) is further stacked under the roof sheet 5, and heat-sealed together. The peripheral sheet 7 is laid under the U-shaped drainage groove 9 so that rainwater falling on the roof sheet flows directly into the U-shaped drainage groove 9.

ルーフシート５が強い日差しに晒されると、紫外線で劣化するだけでなく、槽内温度が高くなり過ぎることがある。そこで、ルーフネットの上に遮光保護マット１０を被せて接着する。   If the roof sheet 5 is exposed to strong sunlight, it not only deteriorates with ultraviolet rays, but the temperature in the tank may become too high. Therefore, the light shielding protective mat 10 is put on the roof net and bonded.

家畜小屋から出る汚水は、固形分を取り除かれた後、一端の流入管１１からこの密閉処理槽２に入り、約50日滞在し、反対側の流出管１２から次の処理槽（好気処理）に向かってゆっくりと自然流下して行く。この間、汚水は空気を断った状態に保たれ、嫌気性菌の働きで、汚水中の有機物が還元的分解を受け、ガス化分解する。発生するガスは、主としてメタンガスと炭酸ガスである。   After the solid content is removed, the sewage discharged from the livestock shed enters the sealed treatment tank 2 through the inflow pipe 11 at one end and stays for about 50 days. From the outflow pipe 12 on the opposite side (the aerobic treatment) ) Slowly flow down naturally toward. During this time, the sewage is kept in a state where the air is cut off, and the organic matter in the sewage is subjected to reductive decomposition and gasification decomposition by the action of anaerobic bacteria. The generated gas is mainly methane gas and carbon dioxide gas.

密閉処理槽２ではこのようにガスが発生するので、槽内圧力は大気圧以上になり、その圧力でルーフシート５は上に膨らむ格好で支持される。したがって、降雨はルーフシートの上に溜まらないで、Ｕ字溝に落ちる。   Since the gas is generated in the sealed treatment tank 2 in this way, the pressure in the tank becomes equal to or higher than the atmospheric pressure, and the roof sheet 5 is supported in such a manner as to swell upward by the pressure. Therefore, the rain does not collect on the roof sheet but falls into the U-shaped groove.

槽内圧力が過大になるのを防止するために、圧力逃し弁１３を設ける。バクテリアの活動が弱まる厳寒時などには槽内内圧が低くなってルーフシートが垂れ下がるおそれがある。しかし、このようなときでも、図１に鎖線で示すように、汚水上に浮力体６が浮いてルーフシート５を支えるので、ルーフシートがひどく垂れ下がることはない。したがって、その上に溜まる雨水の量は少なく、ルーフシートが破けるようなことはない。なお、槽内圧力が上がらないときは、コンプレッサを使って槽内に圧搾空気を吹き込むようにしてもよい。   In order to prevent the pressure in the tank from becoming excessive, a pressure relief valve 13 is provided. When the activity of bacteria weakens, such as in extreme cold, the internal pressure of the tank becomes low and the roof sheet may hang down. However, even in such a case, as shown by a chain line in FIG. 1, the buoyant body 6 floats on the sewage and supports the roof sheet 5, so that the roof sheet does not drastically hang down. Therefore, the amount of rainwater that accumulates on the roof is small, and the roof sheet does not break. In addition, when the pressure in a tank does not rise, you may make it blow compressed air in a tank using a compressor.

密閉処理槽の横断面図であるIt is a cross-sectional view of a sealed treatment tank 同じく平面図である。It is also a plan view. 図１のＡ部拡大図である。It is the A section enlarged view of FIG.

符号の説明Explanation of symbols

１ 遮水シート
２ 処理槽
５ ルーフシート
６ 浮力体
１３ 圧力逃し弁 DESCRIPTION OF SYMBOLS 1 Water shielding sheet 2 Processing tank 5 Roof sheet 6 Buoyant body 13 Pressure relief valve

Claims (4)

地面に穴を掘ってその内面を遮水シートで覆うと共に、該遮水シートに縁部を接合したルーフシートで該穴の上面を覆って、密閉式の汚水処理槽を形成し、槽内に貯留した汚水中の有機物がバクテリアの働きで分解し、そのとき発生するガスで槽内を大気圧以上の圧力に保持して、該ルーフシートを浮揚支持するようにしたシート製汚水処理槽   A hole is dug in the ground and the inner surface is covered with a water shielding sheet, and the top surface of the hole is covered with a roof sheet having an edge joined to the water shielding sheet to form a sealed sewage treatment tank. Sewage treatment tank made of sheet in which the organic matter in the stored sewage is decomposed by the action of bacteria, and the inside of the tank is kept at a pressure higher than atmospheric pressure by the gas generated at that time, so that the roof sheet is floated and supported. 槽内の圧力を高めるために、空気を圧入する手段を設けた請求項１に記載のシート製密閉汚水処理槽。   The sealed sewage treatment tank made of sheet according to claim 1, wherein means for press-fitting air is provided to increase the pressure in the tank. 槽内の圧力が過大になるのを防ぐため、圧力逃し弁を設けた請求項１または２に記載のシート製密閉汚水処理槽。   The sheet-made sealed sewage treatment tank according to claim 1, wherein a pressure relief valve is provided to prevent the pressure in the tank from becoming excessive. 該ルーフシートの裏面に、該槽に貯留された汚水上に浮く浮力体を取り付けた請求項１、２または３に記載のシート式汚水処理槽。   The sheet-type sewage treatment tank according to claim 1, 2 or 3, wherein a buoyant body that floats on the sewage stored in the tank is attached to the back surface of the roof sheet.
JP2003279526A 2003-07-25 2003-07-25 Sealed sewage treatment tank made of sheet Expired - Lifetime JP4324427B2 (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010535104A (en) * 2007-07-31 2010-11-18 アクアファイバー・テクノロジーズ・コーポレーション Water purification and biosolids collection system and related methods
JP2011050917A (en) * 2009-09-04 2011-03-17 Toshiba Corp Anaerobic fermentation system
JP2012035222A (en) * 2010-08-10 2012-02-23 Toshiba Corp Methane fermentation tank, and construction method of cover sheet for tent
JP2012161761A (en) * 2011-02-08 2012-08-30 Toshiba Corp Methane fermentation tank and construction method of bottom sheet
CN115852893A (en) * 2022-12-06 2023-03-28 广东生太修复科技有限公司 River surge basin treatment system and treatment method

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010535104A (en) * 2007-07-31 2010-11-18 アクアファイバー・テクノロジーズ・コーポレーション Water purification and biosolids collection system and related methods
JP2011050917A (en) * 2009-09-04 2011-03-17 Toshiba Corp Anaerobic fermentation system
JP2012035222A (en) * 2010-08-10 2012-02-23 Toshiba Corp Methane fermentation tank, and construction method of cover sheet for tent
JP2012161761A (en) * 2011-02-08 2012-08-30 Toshiba Corp Methane fermentation tank and construction method of bottom sheet
CN115852893A (en) * 2022-12-06 2023-03-28 广东生太修复科技有限公司 River surge basin treatment system and treatment method
CN115852893B (en) * 2022-12-06 2023-08-15 广东生太修复科技有限公司 River surge flow field treatment system and method

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