JP3744699B2 - Coagulation precipitation method and apparatus - Google Patents

Description

【００８３】
【表２】

この表１の結果から分かるように、比較例１では実施例１よりもフロック形成槽中の砂濃度が低く、これは砂がフロック形成槽の下部に沈降したことによることが認められた。また、砂の投入量が多い場合はフロックがより重くなることから、沈降量が更に増加することが認められた。
【００８４】
また表２の結果から分かるように、フロック形成槽での砂の沈降が多い比較例の場合の処理水の濁度は悪く、その傾向は砂投入量が７５０ｇのときより２０００ｇのときの方が顕著に現れた。
【００８５】
更に、表１の比較例１における砂投入量２０００ｇのときのフロック形成槽中の砂濃度は、実施例１における砂投入量７５０ｇのときの同砂濃度よりも高いにもかかわらず、処理水の水質は比較例１の場合の方が悪く、沈澱槽ＬＶを高くするほど水質が悪くなる傾向が大きくなった。
【００８６】
これらのことから、本発明の方法、装置が凝集沈澱処理に有効であることが確認された。
【００８７】
【発明の効果】
本願の各請求項の発明によれば、以下の効果が奏される。
【００８８】
請求項１の発明によれば、フロック形成処理の槽に導入する被処理水を槽底部から上向流で流入させて循環流動をこの槽内に生じさせるので、フロック形成槽の底部に沈積するフロックを循環流動で巻き上げることができ、高い流速を維持しながら、被処理水中に含まれる懸濁物（ＳＳ）と添加した砂とを吸合し粒径の大きなフロックに成長させることができる。これによって、沈澱分離の槽に流入する微フロックの量を少なくできて、例えば５０〜１５０ｍ／ｈという高流速を保持しながら、大部分の懸濁物（ＳＳ）を粒径が大きく沈降速度が大きいフロックとして沈澱槽で迅速に沈降分離することができ、水質の優れた処理水を得ることができるという効果が奏される。
【００８９】
請求項２の発明によれば、フロック形成処理の槽内に、槽底部から上向流を含む循還回流を生じさせて底部に沈降するフロックを巻き上げることができるので、フロック形成処理の際にフロックの沈積を招くことがなく、ＳＳ及び砂を吸合したフロックを大きく成長できるので、例えば５０〜１５０ｍ／ｈという高流速での被処理水の通水を行いながら、微フロックの沈澱分離の槽からの流出を抑制した処理を行うことができるという効果が奏される。
【００９０】
請求項３の発明によれば、原水（被処理水）のフロック形成槽への導入を上向流で行うことと、該槽内での被処理水の循環流動を整流化することを同時に行うことによって、循環流動流の促進作用と、槽内に設置した隔壁による循環流動の整流と旋回羽根装置等による促進作用が相俟って、フロック形成処理の槽内における被処理水の流動がより一層安定し、沈降速度が大きい大フロックが良好に成長し、微フロックが沈澱分離の槽に移行する量を低減することができる。従って、処理水の水質向上に効果がある。
【００９１】
請求項５の発明によれば、従来に比べて高流速での凝集沈澱処理が行え、あるいは小規模の設備で大量の原水（被処理水）処理をすることができる。
【００９２】
請求項６の発明によれば、フロック形成槽内における被処理水の流れを原水の導入によって与え、底部に沈積し易い大フロックをこの導入水で巻き上げるので該槽の底部にフロックが沈積する虞を軽減ないし解消でき、しかもそのための構成が比較的簡易な構造で実現できる。
【００９３】
請求項７の発明によれば、上向流と下向流の縦方向流路が流路設定隔壁により区画されるので、流動促進手段により促進されるこれらの各流路を流れる循還流動流が整流されてフロックの破壊を招く虞を軽減させ、ＳＳ，砂あるいは微フロックの吸合が良好に行われる。
【００９４】
請求項８の発明によれば、越流板を越えて沈澱槽に移行・流入する被処理水の流れの方向を下向きに案内するので、フロックの沈降・沈澱する傾向を高めると共に、同時に小フロックが溢流装置側に流れる傾向を抑制することができる。
【００９５】
請求項９の発明によれば、隔壁が上下蛇行状に入り組み、上向き−越流−下向き（沈澱槽内に流入）という大フロックの円滑・迅速な沈降促進と、微フロックの水面側への移行傾向の低減化という効果が奏される。
【００９６】
請求項１０の発明によれば、略二重円筒型のフロック形成槽の内筒内外に上下反対向きの流れを循環させ、この流れを旋回羽根装置等の流動促進手段で促進することで全体として整流化した流れを形成でき、フロックの巻き上げとフロックの成長を良好に得ることができる。
【００９７】
請求項１１の発明によれば、下向流のための第二の縦方向流路を形成する部分が、沈澱槽への被処理水の移行の前段で中間槽的な役割を示しながら、この部分の流路の底部に沈積する虞のあるフロックは上向流でフロックを巻き上げる作用を有する第一の縦方向流路にフロックを戻すことができるので、フロックの破壊を抑制しながら、該フロックの巻き上げを良好に行うことができる。
【００９８】
請求項１２の発明によれば、下向流から上向流に転向する循環流動流をフロック形成槽の底部において円滑に流すことができて、フロックの破壊を抑制しながらフロックの巻き上げを良好に行うことができる。
【００９９】
請求項１３の発明によれば、フロックを巻き上げるフロック形成槽の底部において水平断面積が小さいので流速を高めて巻き上げ力を大きくすることができ、したがってフロックの沈積をより効果的に防ぐことができるという作用が得られる。
【図面の簡単な説明】
【図１】 本発明の実施形態１の装置の構成概要を示した図。
【図２】 本発明の実施形態２の装置の構成概要を示した図。
【図３】 本発明の実施形態３の装置の構成概要を示した図。
【図４】 本発明の実施形態４の装置の構成概要を示した図。
【図５】 従来の凝集沈澱装置の一例を示した図。
【図６】 フロック形成槽から沈澱槽にフロックを越流式で移行させる場合の問題を図解的に示した図。
【図７】 フロック形成槽から沈澱槽にフロックを越流式で移行させる場合の問題を図解的に示したもう一つの図。
【図８】 本発明の処理試験（実施例）を行うために図３に示した実施形態３の装置を簡略化した凝集沈澱装置を示した図。
【図９】 図８の装置を用いた処理試験と対比する比較例を行うために図５の従来装置を簡略化した凝集沈澱装置を示した図。
【符号の説明】
１，１１，１２，１３・・・フロック形成槽
１０１，１１１，１２１，１３１・・・胴部
１１２・・・中間胴部
１０２，１１３，１２２，１３２・・・コーン部
１０３，１１４，１２３・・・上部隔壁
１０４，１１５，１２４・・・開口
１１６・・・流路設定隔壁( 案内壁）
１１７・・・開口
２・・・沈澱槽
２０１・・・越流壁
２０２・・・胴部
２０３・・・コーン部
２０４・・・溢流樋
２０５・・・越流水流通ガイド壁
３・・・原水（被処理水）導入管
４，４１，４２・・・旋回羽根装置
４０１，４１１，４２１・・・モータ
４０２，４０３・・・旋回羽根
４０４・・・回転軸
５・・・無機凝集剤供給管
６・・・高分子凝集剤供給管
７・・・砂供給装置
７０１・・・ポンプ
７０２・・・サイクロン
７０３・・・汚泥排出管[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a method and apparatus for agglomerating and precipitating a suspension (SS) in water to be treated, and more specifically, by adding high-density particles such as sand and a chemical treatment agent to the water to be treated, The present invention relates to an efficient SS removal method and apparatus for precipitating as agglomerates having a high sedimentation rate.
[0002]
[Prior art]
  As a coagulation precipitation method for removing fine suspensions (SS) in water to be treated, a method and an apparatus for rapidly sedimentation and precipitation separation by coagulation and flock growth of SS are disclosed in, for example, French Patent No. 1411792. French Patent No. 1501912 (filed on Sep. 28, 1969), French Patent No. 2071027 (filed on Dec. 16, 1969), Japanese Patent No. 2634230, Japanese Patent Laid-Open No. 8-47606, etc. Yes.
[0003]
  In this method, fine suspended particles that cannot be separated at high speed by natural sedimentation in a stock solution are mixed with insoluble and high-density particles such as sand (hereinafter collectively referred to as “sand”) and a chemical treatment agent. Utilizing it, it is grown into agglomerates (floc) containing SS, and is made into a high-density agglomerate (floc) that easily incorporates sand and is separated from the water to be treated.
[0004]
  According to this method, the floc in the case of sedimentation by a general coagulation sedimentation method is about 1.01 to 1.02, and the density is small and the sedimentation speed is slow. Because it contains sand with a density of about 2.7, a large sedimentation speed can be obtained, and floc can be settled and separated quickly while flowing the water to be treated at a high flow rate. It is thought that it is advantageous in that the scale of the apparatus can be reduced if the per unit treatment flow rate is increased and the amount of treated water is the same.
[0005]
  The principle configuration of the apparatus for carrying out this method is, for example, a coagulation tank in which an inorganic coagulant and a polymer coagulant are added to raw water and agitated, and flocs aggregated into small particles in this coagulation tank are grown into large flocs. The floc forming tank, the floc having a large sedimentation speed including the sand grown in this floc forming tank is settled and settled on the bottom of the tank, and the treated water overflows from the upper part of the tank as the supernatant water and is separated from each tank. It is configured as a one-pass distribution type processing tank facility provided in order. And the raw water (treated)Water) Is provided with a stirring state and a flow rate suitable for the treatment in the respective tanks for agglomeration, floc formation and precipitation (see FIG. 5).
[0006]
  However, in reality, the technology of this method is not widely used. This is because some important problems have not been solved yet when applied to an actual industrial scale apparatus.
[0007]
  One of the problems is not limited to the above method, but is also observed when SS is removed by agglomeration and precipitation. However, flocs are produced with a uniform size and a uniform density. Rather, it is difficult to avoid the tendency that the distribution of the sedimentation rate of flocs spreads greatly as a result of the generation of a material having a large sedimentation rate due to the addition of sand.
[0008]
  In other words, the growth of flocs varies depending on the quality of the water to be treated, the types and amounts of various chemical treatment agents added, the state of dispersion of sand, the presence of SS, local changes in flow velocity, etc. Therefore, it is inevitable that the distribution of the sedimentation velocity of the individual flocs that are generated / growth widens. In other words, even if the flocs are generated under the same conditions as seen in the macro (macroscopic), the diameters are about 1 to 4 mm among the generated many flocs when viewed in the micro (microscopic). Some of them are large and contain a large amount of sand, so that the sedimentation speed reaches 15 to 1000 m / h. On the other hand, the diameter is as small as about 100 to 200 μm and is not combined with sand or only a small amount of sand. Since they are not bonded, there will be micro flocs with a very slow sedimentation speed of about 0.5-2 m / h, and there will be many micro flocs in the water to be treated that pass through each tank in one pass. A large amount flows into the separation tank.
[0009]
  Therefore, as a measure for preventing the outflow of such fine flocks, for example, in the method described in the above-mentioned Japanese Patent No. 2634230, as shown in FIG. It is proposed to capture the overflowing fine floc contained in the separator.
[0010]
[Problems to be solved by the invention]
  The separation plate installation method is effective in that the amount of fine floc contained in the overflowing treated water (supernatant water) can be reduced, but on the other hand, there is a disadvantage in terms of installation equipment that a separation plate is required. . In addition to this, the burden for maintenance and inspection of the separation plate where clogging is unavoidable is large, the running cost increases, measures to temporarily stop the device to recover clogging of the separation plate, In particular, it is difficult to temporarily store treated water (or raw water) when the equipment is stopped in equipment that requires continuous operation.
[0011]
  By the way, in order to make the formation flock as much sand as possible so that the particle size is large and the density is large, the transition from the flock formation tank to the settling tank is performed as shown in the example of FIG. It is better to go beyond. This is because if a transition port to the sedimentation tank is provided at the lower part of the floc formation tank, the high density flocs with sand are transferred to the sedimentation tank quickly, and only relatively light flocs remain in the floc formation tank. This is because the reaction time required for floc formation becomes longer. According to the method of moving over the upper part of the overflow plate, the floc concentration is maintained high in the floc forming tank, the contact opportunity for sucking fine flocs generated by the aggregation of the inorganic flocculant is increased, and the sedimentation rate is increased. Large flocs can be grown, the reaction time required for floc formation can be shortened, and the floc formation tank can be miniaturized.
[0012]
  However, in the system in which the floc is transferred to the sedimentation tank beyond the upper part of the overflow plate, flocs having a large particle size and heavy, and sand that has not been sucked into the flocs sink to the bottom of the floc formation tank. There is a difficulty. This problem has resulted in the fact that large flocs of flocs gradually accumulate at the bottom of the floc forming tank, as shown in FIGS. 6 and 7, and in other cases, this type of equipment usually has a sedimentation tank. The sand is separated from the sludge collected in step 1 and recycled so that it is added again to the flocculation tank. However, the amount of sand to be reused is insufficient, so that flocs of the desired density are not formed. This is explained as a problem in which the formation of light flocs is caused, and the flocs leak into the treated water in the sedimentation tank, resulting in deterioration of the treated water. Although the problem of sand shortage can be solved by adding a shortage of sand from the outside, this will lead to an increase in sand addition equipment and operating costs, and the flow rate of raw water When the flow condition fluctuates due to changes in the water temperature or the water temperature, the accumulated flocs and sand flow and return to the circulation flow of the floc forming tank, and the balance of the amount of sand circulating in the system changes. As a result, problems such as deterioration of reactivity due to a short path due to shrinkage of the flow path, decay of accumulated flocs, and the like may occur, resulting in failure to perform stable operation.
[0013]
  In addition, in order to eliminate the problem of heavy flocs accumulating in the floc forming tank by the overflow method, it is conceivable to perform strong stirring in the floc forming tank. Invited, the floc particle size is reduced and the sedimentation rate is lowered, leading to the problem that the upward flow in the sedimentation tank cannot be set at a high flow rate. For these reasons, it is necessary to satisfy the trade-off requirement that it is necessary to prevent the floc from breaking down and avoiding it as much as possible in the floc forming tank. Not. For example, an intermediate tank is provided between the floc-forming tank and the sedimentation tank. In the floc-forming tank, sedimentation of sand and large flocs is prevented with relatively strong stirring, and flocs are grown with weak stirring in the intermediate tank. However, since this method involves an increase in the number of tanks, an increase in equipment costs due to an increase in the number of agitators, an increase in operating costs, an increase in the installation area, etc., this is an industrial facility. Is not advantageous.
[0014]
  The present inventor has made the present invention on the basis of the facts found when diligent study was advanced in order to solve the various problems of the prior art as described above.
[0015]
  That is, the present invention is generally not necessarily uniform (large) in the technology based on growing SS and sand to grow high-density floc in order to remove suspended matter (SS) in raw water. One of the purposes is to reduce as much as possible the problem that flocs averaged in the sedimentation velocity due to density, etc. are not generated.
[0016]
  Another object of the present invention is to make it possible to realize a method capable of increasing the processing flow rate by generating flocs containing sand with as simple and compact equipment as possible, thereby widely spreading the above technology as industrial scale equipment. It is an object of the present invention to provide a method and apparatus for removing agglomeration precipitates from SS in raw water.
[0017]
[Means for Solving the Problems]
  The above object can be achieved by the inventions of the respective claims described in the claims of the present application.
[0018]
  That is, according to the present inventor's earnest study to solve the various problems described above, it is possible to smoothly and sufficiently circulate and flow large flocs and sand having a high density in the floc forming tank, and the above overflow. The water to be treated is transferred from the floc formation tank to the sedimentation tank by the formulaTogaI found it important. That is, with the former configuration, by causing the fluid circulation to prevent sedimentation and accumulation at the bottom of the floc formation tank of the heavy large flocs, it is possible to increase the opportunity to absorb the fine flocs to the circulating large flocs. This is effective in reducing the fine flocs transferred to the settling tank, and by adopting the latter overflow type transfer method, only the large flocs move quickly to the settling tank and the fine flocs It is possible to prevent the problem that the reaction time required for floc formation is prolonged and left behind. From this point of view, the invention of each claim of the present application adopts a configuration capable of exhibiting a flow promoting action suitable for circulating and flowing while preventing large flocs from settling in the floc forming tank. It is characterized by that.
[0019]
  The invention of the suspension coagulation precipitation method according to claim 1 circulates the water to be treated containing the suspension (SS) and added with a chemical treatment agent necessary for floc formation and insoluble fine particles having a large specific gravity in the tank. A floc forming treatment for growing flocs containing insoluble fine particles while flowing and a precipitation treatment for precipitating and separating flocs containing insoluble fine particles grown to have a large sedimentation rate from water by the treatment are said floc forming treatment. A coagulating sedimentation method in which each of the treatments is carried out sequentially so that the water to be treated continuously flows over the overflow plate that divides the floc precipitation separation tank from the tank of The flow of water to be treated in the tank that performs the treatment is such that the water to be treated flows in from the bottom of the floc forming tank in an upward flow, and the floc that sinks to the bottom is wound up by the upward flow. Characterized in that so as to flow.
[0020]
  In the above configuration, sand (specific gravity of about 2.7) is usually used as the “insoluble fine particles” having a large specific gravity, and is not limited, but generally has a particle size of about 10 to 200 μm, preferably 50 to 200 μm. A degree is preferred. In the following description, the insoluble fine particles will be described using sand as a representative.
[0021]
  The sedimentation velocity v in the fluid of particles such as sand is expressed by the following Stokes equation.
  v = g (ρs−ρ) d² / Μ / 18
(Where ρs: particle density, ρ: water density, d: particle diameter, μ: water viscosity coefficient, g: gravity acceleration)
If a sand having a very large specific gravity and particle size is used, the rate of sand settling in the floc forming tank without adsorbing to the floc increases, so sand with the above particle size range is suitable. .
[0022]
  As a “chemical treatment agent” necessary for floc formation, generally, inorganic flocculants such as polyaluminum chloride (PAC), ferric chloride, ferric sulfate, anionic polymer flocculants, amphoteric A polymer flocculant such as a polymer flocculant is used in combination. Inorganic flocculants are used to agglomerate suspensions (SS) and sand in the water to be treated, and polymer flocculants are used to grow these agglomerates into large flocs.
[0023]
  Although the method of adding these sand and flocculant is performed by adding to the tank of a flock formation process, an inorganic flocculant can also be added in the middle of the introduction pipe | tube of to-be-processed water. Moreover, you may provide the tank of the strong stirring aggregation process which adds an inorganic flocculant in the front | former stage of the tank of a flock formation process.
[0024]
  The suspension state in which the suspension aggregates and flocs grow in the floc-forming tank is provided by causing a circulation flow with, for example, a swirl blade device or a stirrer to such an extent that sand having a large specific gravity does not settle.
[0025]
  The floc sedimentation tank that sediments flocs containing sand and separates them from water is configured to transfer the water to be treated from the floc forming tank over the upper part of the overflow plate. The floc contained in the water to be treated introduced into the tank for precipitation separation has a large particle size and a high density, so that it quickly settles at the bottom of the settling tank. As a result, most of the suspension (SS) contained in the water to be treated is contained in the sedimented floc and separated from the water. On the other hand, water is discharged from the upper part of the settling tank to the outside, for example, in the form of overflow. At this time, fine flocs that flow to the upper side of the settling tank together with water without being settled may be captured by passing through a filler packed bed provided on the upper side of the settling tank. Even in the case of using the filler packed bed in the present invention, since the flocs and the like are circulated and flowed on the flow of the water to be treated in the floc forming tank, the fine flocs are absorbed and grow. There are few fine flocks flowing into the tank and there is little burden of clogging. As such a filler-filled layer, for example, a large number of fillers (contact materials) are randomly accumulated to partially restrict the upward flow to form stagnation on the back side of the filler flow. It is preferable to use one that retains the fine flocs at the portion and performs the filtration action of the fine floc growth and sedimentation. Such a filler-filled layer can be formed by, for example, using plastic short tube-shaped pieces having a diameter of about 4 to 12 mm and a length of about 15 to 20 mm as a filler, and randomly collecting them. However, the present invention is not particularly limited to this, and it is also possible to use a filler in which a large number of holes are formed in the spherical surface of an inner hollow sphere, or terralet packing. In addition, this packed material packed bed needs to function as a water flow path for the upward flow of the high flow rate, so that the entire layer has a porosity as high as possible, but forms a stagnation part with respect to the upward flow. Therefore, a filler having a size and shape that can have a large surface area is preferably selected and used.
[0026]
  The floc that has settled at the bottom of the settling tank is discharged out of the apparatus by a drawing means such as a sludge drawing pump, and if necessary, in the above-mentioned Japanese Patent No. 2634230, Japanese Patent Laid-Open No. 9847606, Japanese Patent Laid-Open No. 9-141006. As described, sand can be separated from the extracted sludge using a separator such as a cyclone and reused.
[0027]
  The most significant feature of the present invention is that the water to be treated introduced into the tank for the flock formation treatment is caused to flow in an upward flow from the bottom of the tank so as to generate a circulating flow in the tank. As a result, the floc that settles at the bottom is wound up by circulation flow, and while maintaining a high flow rate, the suspension (SS) contained in the water to be treated and the added sand are absorbed to grow into a floc having a large particle size. Thus, the amount of fine floc flowing into the precipitation separation tank can be reduced.
[0028]
  According to the present invention, for example, most of the suspension (SS) in the water to be treated has a large particle size and a high sedimentation speed while passing the water to be treated at a high flow rate of 50 to 150 m / h. It becomes a floc and can be quickly settled in a settling tank.
[0029]
  In the invention of the method for coagulating sedimentation of the suspension of claim 2, the water to be treated is directed upward from the bottom of the tank in order to generate a circulating flow that winds up the floc settled on the bottom of the tank of the floc forming process of claim 1. Instead of flowing in the flow, it is set so that the circulating flow of the water to be treated flows in one direction along the flow path defined by the partition in the tank for the flock formation treatment, and at the bottom of the tank It is characterized in that the above-mentioned circulating flow is turned and flows from the counter flow to the upward flow so as to wind up the floc that settles at the bottom of the tank.
[0030]
  In the above configuration, the circulating flow flowing in one direction in the passage formed by the partition walls can be generated using, for example, one or a plurality of swirl blade devices.
[0031]
  According to the present invention, the floc that is settling to the bottom can be wound up in the floc forming tank by generating a circulating circulation including an upward flow rising inward or outward from the bottom of the tank. Since the flocs can grow greatly by inhaling SS and sand without causing sedimentation of flocs in the treatment tank, for example, water to be treated is passed at a high flow rate of 50 to 150 m / h. While carrying out the treatment, it is possible to carry out a treatment that suppresses the outflow of the fine floc from the precipitation separation tank.
[0032]
  The invention of claim 3 is characterized by having both of the above methods, and according to the invention, the circulation flow is promoted by introducing the water to be treated in the upward flow from the bottom of the tank, Combined with the rectification of the circulation flow by the installed partition walls and the promoting action by the swirl blade device, etc., the circulation flow in the tank for floc formation treatment is more stable, and flocs with large particle size and high sedimentation speed grow well In addition, the amount of fine floc transferred to the precipitation separation tank can be reduced.
[0033]
  The invention of claim 5 is characterized in that, in each of the above-mentioned inventions, the upward flow velocity of the fluid circulation flow given to the bottom of the tank for floc forming treatment is 50 m / h or more, preferably 200 m / h or more. .
[0034]
  According to this invention, it is possible to perform a coagulation sedimentation process at a higher flow rate than in the past, and to process a large amount of raw water (treated water) with a small-scale facility.
[0035]
  The invention of the suspension coagulation sedimentation apparatus according to claim 6 circulates the water to be treated containing the suspension (SS) and containing the chemical treatment agent necessary for flock formation and insoluble fine particles having a large specific gravity in the tank. A floc-forming tank that grows flocs containing insoluble fine particles while flowing, and flocs that have been grown to have a large sedimentation speed by containing the insoluble fine particles are precipitated at the bottom of the tank and the separated water is discharged from the upper part of the tank. A floc sedimentation tank, and an overflow channel for allowing the water to be treated to flow from the floc formation tank to the floc sedimentation tank over the upper part of the overflow plate provided to partition both tanks; The floc-forming tank is connected to a bottom of the tank by a treated water introduction pipe for flowing the treated water in an upward flow.
[0036]
  In the above-described configuration, the floc forming tank can be of various types such as a horizontal section having a cylindrical shape, a rectangular shape, a deformed shape in which a curve and a straight line are combined (for example, a combination of a semicircular shape and a rectangular shape), etc. The structure can be determined from the flow rate of the water to be treated in the flock formation tank, the flow rate of the overflow water determined by the cross-sectional area of the overflow channel, and the like.
[0037]
  Further, the method of discharging from the upper part of the settling tank is not limited, but it is usually preferable to use an overflow type using a dredging device having an overflow weir because the structure is simple.
[0038]
  According to the present invention, the flow of water to be treated that circulates in the floc forming tank can be provided by introducing raw water, and a large floc that easily deposits at the bottom is wound up with the introduced water. The risk of sedimentation is greatly reduced or eliminated.
[0039]
  In the invention of the apparatus for coagulating and precipitating a suspension according to claim 7, water to be treated is circulated in a tank containing a suspension (SS) and added with a chemical treatment agent necessary for floc formation and insoluble fine particles having a large specific gravity. A floc-forming tank that grows flocs containing insoluble fine particles while flowing, and flocs that have been grown to have a large sedimentation speed by containing the insoluble fine particles are precipitated at the bottom of the tank and the separated water is discharged from the upper part of the tank. A floc sedimentation tank, and an overflow channel for allowing the water to be treated to flow from the floc formation tank to the floc sedimentation tank over the upper part of the overflow plate provided to partition both tanks; In the floc-forming tank, the floc formation tank includes a vertical flow path for the upward flow and a vertical flow path for the downward flow in the vertical direction. An extended channel setting partition is provided. In addition, a flow promoting means for circulating and flowing the water to be treated from any one of the vertical flow paths to the other vertical flow path and turning the flow of the water to be treated to turn the downward flow upward from the lower part of the partition wall The portion is provided close to the bottom of the tank.
[0040]
  In the above configuration, the flow path setting partition wall that divides the upward flow and the downward flow is generally formed by a substantially vertical plate, but is not limited to this vertical plate. It can also be provided in combination with an inclined plate or the like so as to be suitable for circulation.
[0041]
  The flow promoting means can be configured using a swirl blade device, a stirrer, or the like.
[0042]
  According to the present invention, the vertical flow path of the upward flow and the downward flow is partitioned by the flow path setting partition wall, so that the circulating recirculation dynamic flow flowing through each of the flow paths promoted by the flow promoting means is rectified. Thus, there is an effect that the possibility of causing breakage of the floc is reduced, and the SS, sand, or fine floc is satisfactorily absorbed.
[0043]
  According to an eighth aspect of the present invention, in the apparatus provided with the flow path setting partition wall, the overflow channel is provided in the overflow plate and the settling tank, and guides for introducing and guiding the overflow water downward into the settling tank. It has a wall.
[0044]
  According to the present invention, since the direction of the flow of the water to be treated that flows into and flows into the settling tank beyond the overflow plate is guided downward, the tendency of the floc to settle and settle is increased, and at the same time, the small floc overflows. The effect | action which suppresses the tendency which flows into the apparatus side is acquired.
[0045]
  The invention of claim 9 is an apparatus provided with the flow path setting partition wall, wherein the overflow plate meanders vertically by the overflow plate and the overflow water distribution guide walls respectively provided in the floc forming tank and the sedimentation tank on both sides of the overflow plate. The overflow water distribution guide wall on the flock formation tank side is suspended from the water surface into the water, and the water to be treated that faces the flock formation tank at the middle position in the vertical direction of the flock formation tank It is provided so that an inflow opening may be formed.
[0046]
  The above configuration is typically a configuration in which an overflow plate located below a certain depth from the water surface is provided between the partition walls (overflow water distribution guide walls) that divide both tanks suspended from above the water surface. In this way, the bulkhead enters the upper and lower meandering (labyrinth-like), and the smooth and quick settling of the large flock of upward-overflow-downward (inflow into the settling tank) The effect of promoting and reducing the tendency of the fine floc to move to the water surface can be obtained.
[0047]
  The invention of claim 10 is an apparatus provided with the above-mentioned flow path setting partition wall, wherein the flow path setting partition wall provided in the flock formation tank is a vertically-opened cylindrical wall installed in the flock formation tank, A flow promoting means for promoting the circulation flow is installed inside the cylindrical wall.
[0048]
  According to this invention, the flow in the upside down direction is circulated between the flow path inside the inner cylinder and the flow path between the inner cylinder and the outer cylinder inside the substantially double-cylindrical floc forming tank. The flow can be promoted by a flow promoting means such as a swirl blade device, so that a rectified flow can be formed as a whole, and the floc winding and the floc growth can be obtained well.
[0049]
  The invention according to claim 11 is the apparatus provided with the flow path setting partition wall, wherein the flock forming tank includes a first vertical flow path for an upward flow set in the vertical direction set by the flow path setting partition wall. A second vertical flow path for a short downward flow in the vertical direction that is biased toward the upper side of the first vertical flow path and defined by the flow path setting partition wall. The vertical channel is connected to the sedimentation tank through the overflow channel, and the lower part of the second vertical channel is connected to the first vertical channel so that the floc can be returned and circulated. It is characterized by being.
[0050]
  According to the present invention, the portion that forms the second longitudinal flow path for the downward flow has a role as an intermediate tank in the previous stage of the transfer of the water to be treated to the settling tank, and the flow of this part is The flocs that may be deposited at the bottom of the road can be returned to the first longitudinal flow path that has the effect of winding up the flocs in the upward flow, so that the flocs can be wound up while suppressing the breakage of the flocs. It can be done well.
[0051]
  The invention according to claim 12 is a configuration in which a water to be treated introduction pipe for allowing the water to be treated to flow in an upward flow from the bottom of the flock forming tank is connected to the floc forming tank, and the circulation flow is unidirectional in the tank. A flow path setting partition wall is provided to flow through the flow path.
[0052]
  According to the present invention, the circulating flow that turns from the downward flow to the upward flow can smoothly flow at the bottom of the flock formation tank, and the floc is wound up well while suppressing the breakage of the flock. be able to.
[0053]
  According to a thirteenth aspect of the present invention, in each of the above-described device inventions, the floc-forming tank is characterized in that the shape near the bottom of the tank is provided in a cone shape in which the horizontal cross-sectional area decreases from the top toward the bottom.
[0054]
  According to the present invention, since the horizontal cross-sectional area is small at the bottom of the flock forming tank that winds up the flock, the flow rate can be increased and the winding force can be increased, so that the flocs can be more effectively prevented from being deposited. can get.
[0055]
  Examples of raw water (treated water) targeted by the present invention include industrial water, river water, factory waste water, and the like.
[0056]
DETAILED DESCRIPTION OF THE INVENTION
  Embodiment 1
  The present example shown in FIG. 1 is an example in which in the flock forming tank 1, a large-density flock that settles and accumulates at the bottom of the flock forming tank 1 is wound up by the force of the flow of raw water (treated water) introduced into the tank 1. The device is shown.
[0057]
  In FIG. 1, reference numeral 1 denotes a flock-forming tank. The tank wall structure that forms the outer shell of the tank body has a trunk portion 101 that forms a vertical cylinder on the upper side, and a lower side that gradually decreases in horizontal cross-sectional diameter toward the bottom. A cone portion 102 and an opening 104 provided below the upper partition wall 103 formed with a part of the body portion 101 as an overflow water flow guide wall are provided. From the opening 104, the partition wall 103 and a part of the next stage sedimentation tank 2 are provided. Through the overflow wall 201 formed as a side wall, the water to be treated is transferred to the sedimentation tank 2 in an overflow manner. The upper body portion 101 is configured by combining a left-side semi-cylindrical portion in the figure and a right-side rectangular portion as viewed in a horizontal plane, and the rectangular tank includes the settling tank described above. Opening 104 for communication, this openingMouth 104 is provided so as to have the upper partition wall 103 that forms 04.
[0058]
  A raw water introduction pipe 3 is connected to the bottom of the cone portion 102 of the flock forming layer 1 so that the raw water is introduced into the tank 1 upward. At the center position, the swirl vane device 4 for circulating flow promotion is installed so as to be suspended from above the tank 1, and the swirl vanes 402 and 403 rotated by the motor 401 face upward at the center position of the tank 1. In the vicinity of the inner wall of the tank, the downward circulation flow is promoted. 404IsThis is a rotating shaft in which the swirl blades 402 and 403 are assembled.
[0059]
  An inorganic flocculant supply pipe 5 is connected in the middle of the raw water introduction pipe 3 to add the inorganic flocculant to the raw water. Reference numeral 6 denotes a polymer flocculant supply pipe, and the polymer flocculant is added into the tank 1 from the side of the cone portion 102 of the flock forming tank 1. Reference numeral 7 denotes a sand supply device, which returns sludge extracted by a pump 701 from the bottom of the sedimentation tank 2 described later to a cyclone 702, separates the sand from the flocs by the cyclone 702, and treats water to be treated in the flock formation tank 1. It is provided so that it may be added to the water surface. In addition, SS other than sand separated by the cyclone is discharged as sludge through a sludge discharge pipe 703, and is subjected to predetermined treatment and disposal.
[0060]
  The floc containing the SS in the raw water together with the sand passes through the overflow wall 201 as described above and is introduced into the sedimentation tank 2 through the floc forming tank 1 having the above configuration. The structure of the tank body of the sedimentation tank 2 is similar to the structure of the flock formation tank 1, and includes a vertical cylindrical body 202 on the upper side and a lower side whose horizontal sectional diameter gradually decreases toward the bottom. An overflow device including a cone portion 203 and an overflow basin 204 for overflowing treated water around the upper part of the tank;TheThe floc quickly settles and settles at the bottom of the cone portion 203, and the supernatant water (treated water) is discharged from the overflow basin 204 to the outside. Reference numeral 205 denotes an overflow water flow that guides the flow direction of the water to be treated that has passed through and overflowed into the settling tank 2 beyond the overflow wall 201.ThroughThis is a guide wall, which increases the tendency of the flocs having a relatively low density to settle and settle, and at the same time acts to suppress the tendency of the flocs to flow to the overflow device side.
[0061]
  The operation obtained by the coagulating sedimentation apparatus of the present example configured as described above will be described. Generally, a large floc having a large particle size and a high density is deposited and deposited on the bottom of the floc forming tank 1. In the apparatus of the example, the bottom of the tank 1 is formed as a cone part 102 and is confined within a relatively small horizontal cross-sectional area, and the raw water is introduced into the tank from the raw water introduction pipe 3 at the bottom of the tank where the cross-sectional area is limited. Is introduced in the upward flow, so that the large flock that accumulates or is about to be deposited on the same portion is wound on the upward flow of the raw water. And since the diameter of the cone part 102 of this tank 1 increases gradually upwards, the force of the above-mentioned floc hoisting by the introduced raw water flow becomes small if it is as it is, but in this example for further promoting this Since the swirl blade device 4 is provided, the upward rising of the floc along the substantially center position of the tank 1 is promoted.
[0062]
  And the force of the upward upward flow which winds up the large floc formed along the centerline of such a tank 1 reaches the cylindrical trunk | drum 101 with a large horizontal cross-sectional area of an upper side, and becomes small gradually, The surrounding wall in this tank 1 It turns to a downward downward flow while diffusing to the side. Therefore, the large flock riding on this flow also rises along the center line from the bottom side of the tank 1 and circulates in the tank 1 on the flow turning to the downward flow toward the upper side of the tank 1. This circulation is promoted by the above-described raw water inflow position (tank bottom) and direction (upward) and the swirl vane device 4.
[0063]
  On the other hand, since very fine flocs and SS in the raw water to which the inorganic flocculant has been added before introduction into the tank 1 and the polymer flocculant ride on the circulation flow, they ride on the flow in the middle of this flow. There is enough opportunity to be absorbed by the flocs that are present. Further, the sand supplied from above the water surface of the tank 1 is sufficiently given a chance of contact with the circulating floc.
[0064]
  Further, the water to be treated is continuously transferred to the settling tank 2 side from the opening 104 to the overflow channel provided at a predetermined position and height of the body 101 of the flock forming tank 1. Since it is flowing, a large proportion of large flocs are transferred to the settling tank 2 along the flow of this transfer.
[0065]
  Therefore, according to this apparatus, since the inflow position and direction of the raw water and the swirl blade device 4 are specified, the circulation flow in the flock formation tank 1 is promoted. The problem of precipitation / deposition is eliminated, and it is not necessary to apply extremely strong agitation, so the risk of breaking the floc is reduced or eliminated. Moreover, since the SS in the raw water and the fine flocs containing the same are given sufficient opportunity to contact the larger flocs in the course of the circulation flow, the rate at which these fine flocs etc. are transferred to the sedimentation tank 2 as they are. Is extremely small, and it is possible to effectively prevent leakage of fine floc from the sedimentation tank. In addition, when a separation plate is provided at the top of the sedimentation tank, the time to block it is much longer than in the conventional example, which is extremely beneficial for reducing the burden of maintenance and inspection to deal with this. is there.
[0066]
  Embodiment 2
  This example shown in FIG.ofSimilar to the first embodiment, a large density floc that settles and accumulates on the bottom of the floc forming tank 11 is wound up by the force of the flow of raw water (treated water) introduced into the tank 11, and this In addition, the apparatus of the example which has the guide wall (flow path setting partition wall) which further accelerates | stimulates the circulation flow of to-be-processed water in the flock formation tank 11 is shown.
[0067]
  The structural feature of this example apparatus is the structure of the flock forming tank 11. That is, the tank wall forming the outer shell structure of the tank 11 has a lower cone part 113 whose diameter gradually increases upward from the bottom of the narrow horizontal cross-sectional area, and a vertical cylindrical shape from the upper end of the cone-like lower part. The intermediate body 112 rises upward, and the upper body 111 continues further upward from the intermediate body. The upper body 111 has a configuration in which a semi-cylindrical portion and a rectangular portion are combined in a horizontal plane as in the first embodiment, and the rectangular portion communicates with the settling tank 2. Provided with dimensions that allow the formation of a second longitudinal flow path as a flow path space for guiding the downward flow of circulation and circulation to a position above the intermediate body 112 at the side of the opening 115 and the upper partition 114 described later. Yes. Further, the intermediate body 112 for raising the raw water introduced in the upward flow from the raw water introduction pipe 3 and the first longitudinal flow path for the upward flow over the vertical upper portion thereof, and the downward flow are guided. The second vertical flow path is narrowly limited and partitioned into a flow path for upward upward flow and a flow path for downward downward flow by a guide wall 116 that partitions the inside of the body of the tank 11. There is a feature that.
[0068]
  The guide wall 116 is formed so as to partition the upper body part into a string shape by a vertical plate across the opposing inner wall, and the lower part thereof has an opening 117 spaced from the tank outer shell wall. By having it, the intermediate body 112 is opened.
[0069]
  And aboveIn the middleA swirl vane device 41 for promoting upward flow is installed in the first vertical flow path for upward upward flow across the intermediate body portion 112 and the vertical upper portion thereof so as to be suspended from above the tank 11. The upward flow is promoted by the swirl blade 412 rotated by the motor 411. Further, the second swirl vane device 42 for promoting the downflow is suspended and installed in the second vertical flow path for the downward flow in the same configuration as described above, and the swirl vane rotated by the motor 421. The downward flow is promoted by 422.
[0070]
  Moreover, although the addition position of the sand of this example is different from the first embodiment in that it is the upper end portion of the cone portion 113 of the flock forming tank 11, the other configuration is the same as that of the first embodiment. For convenience of explanation, necessary components are denoted by the same reference numerals, and others are omitted.
[0071]
  The operation obtained by the coagulation sedimentation apparatus of the present example configured as described above will be described. As in the case of the first embodiment, a large floc having a large particle size and a high density is settled at the bottom of the floc forming tank 11. There is a tendency to deposit.
[0072]
  However, according to the apparatus of this example, the bottom of the tank 11 is formed as a cone portion 113 and is limited to a relatively small horizontal cross-sectional area, and the cross-sectional area is restricted from the raw water introduction pipe 3 to the tank bottom. Since the raw water is introduced into the tank 11 in an upward flow, the large floc that accumulates or is about to accumulate in the same portion is wound on the upward flow of the raw water. And in the tank 11 of this example, in order to further promote the flock winding force, the above-described swirl blade device 41 for promoting the upward flow is provided, and the guide wall 116 is provided to provide a downward flow channel. Is clearly partitioned and the circulating flow is rectified, so that the upward movement of the floc is well promoted.
[0073]
  Then, the upward upward flow that winds up the large floc flows over the guide wall 116 on the upper side of the tank, flows into the downward flow path in which the second swirl blade device 42 is provided, and turns to the downward downward flow. Therefore, the large flock riding on this flow rises along the swirl vane device 41 from the bottom side of the tank 1 and reaches the upper side of the tank and moves to the downflow channel side where the second swirl vane device 42 is provided. Then it turns to a downward flow. Then, a large proportion of the large flocs ride on the flow from the opening 115 to the precipitation tank 2 at the next stage, and transfer to the precipitation tank 2 in the overflow manner in the same manner as in the first embodiment, and are settled and separated. Further, the remaining large flocs descend from the opening 117 at the bottom of the guide wall 116 toward the bottom of the tank 11 and are wound up again by the raw water introduction flow and circulate in the tank.
[0074]
  On the other hand, very fine flocs and SS in the raw water to which the inorganic flocculant has been added before introduction into the tank 11 and further the polymer flocculant are put on the above-mentioned circulation flow to other flocs in the middle of this flow. There is plenty of opportunity for contact to be absorbed. Further, the sand supplied to the tank 11 circulates in the same manner, and a sufficient opportunity to contact the floc is given.
[0075]
  As described above, according to the present apparatus, the circulation flow in the flock formation tank 11 is promoted by the introduction of the raw water in the upward flow and the swirl vane devices 41 and 42, and further compared to the first embodiment, By providing the guide wall 116, the flow path for rising and lowering of the circulating and flowing flow is partitioned, so that the promotion effect can be further improved.
[0076]
  Therefore, the problem that large flocs settle and accumulate in the floc forming tank 1 is reduced / eliminated, and since there is no need to give extremely strong stirring, the risk of flock destruction is also reduced. Including fine flocs, the opportunity to come into contact with larger flocs will be given enough in the middle of the circulation, and these fine flocs will remain in the sedimentation tank as they are2The rate of migration is extremely small, and it is possible to effectively prevent leakage of fine floc from the sedimentation tank.
[0077]
  Embodiment 3
  This example shown in FIG. 3 shows an example in which a large-density large floc that settles and accumulates at the bottom of the floc forming tank 12 is wound up by the force of the flow of raw water (treated water) introduced into the tank 12. It is the same as Embodiment 2 described above in that it has a configuration in which it has a guide wall that further promotes the circulation flow of the water to be treated in the flock formation tank 12, but the guide wall of the apparatus of this example is The upward flow is provided as a vertical guide cylinder 126 that divides and surrounds the periphery of the swirling blade device 4 that promotes the upward flow including the large flocs wound up by the raw water introduction flow, and further rectifies the fluid circulation flow Can be put onRuyoIt is in place. In addition, although the same code | symbol was attached | subjected about the same component as Embodiment 1, description was abbreviate | omitted, but the addition position of the polymer flocculant of the code | symbol 6 is shown as a wall surface position of the guide cylinder 126 in the illustration, In order to avoid complication of the drawing, the pipe is actually extended to the central position of the guide cylinder 126 and added.
[0078]
  According to this configuration, in addition to the effect that the dense flock that settles and accumulates at the bottom of the floc forming tank in the first embodiment can be rolled up by the force of the flow of raw water (treated water) into the tank 12. The guide cylinder 126 can clearly define the upward and downward flow paths of the fluid circulation flow, so that the problem that large flocs precipitate and accumulate in the floc forming tank 12 is eliminated and is extremely strong. Since it is not necessary to give agitation, the risk of breaking the floc is reduced. Furthermore, the SS in the raw water and the fine flocs containing this are given sufficient opportunity during the circulation in contact with the larger flocs.2The rate of migration is extremely small, and it is possible to effectively prevent leakage of fine floc from the sedimentation tank.
[0079]
  Embodiment 4
  This example shown in FIG. 4 is compared with the flock formation tank 13 as compared with the third embodiment.RuharaIt shows an example in which the position and direction of water introduction (supply) are different, and the other structures are different except that the structure for forming the transition flow path of the water to be treated to the next stage sedimentation tank 2 is different. Since it is the same as that of the third embodiment, parts necessary for description are denoted by the same reference numerals and description thereof is omitted. In FIG. 4, the raw water supply pipe 3 is simply connected to the wall surface of the guide cylinder 136, but the actual supply of raw water in this example is directed downward (or substantially at the center of the guide cylinder 136) (or The raw water is introduced upward). In addition, although the circulation direction of the to-be-processed water promoted by the swirl blade device 4 is downward in the guide cylinder 136, it may be opposite (upward) together with the swirl blade device 4.
[0080]
  According to the apparatus of this example, it differs from the apparatus of Embodiment 3 in that the raw water introduction flow is not upward and the direction of the flow of the water to be treated that circulates in the tank 13 is opposite. However, the fluidity of the circulating flow that settles or deposits at the bottom of the floc forming tank 13 or winds up the floc to be deposited is determined by the guide cylinder 136 through the flow path for the upward flow and the flow path for the downward flow. And by the swirl vane device 4, the flow of circulating flow that turns from the center toward the peripheral wall is promoted to the bottom of the flock forming tank, and along the tank wall of the flock forming tank 13. Since an upward flow is formed, a structure for transferring a large floc to the sedimentation tank 2 in an overflow manner can be provided in the vicinity of the floc formation tank 13, and the overall scale of the apparatus of this example is compared with that of the third embodiment. Small There is an advantage that can be designed.
[0081]
【Example】
Example 1, Comparative Example 1
  The test apparatus of FIG. 8 which simplified the apparatus of FIG. 3 was comprised, the test was performed on the following conditions, and the result was shown to following Table 1,2. For comparison, the test apparatus of FIG. 9 which is a simplified version of the conventional apparatus of FIG. 5 is configured and tested in the same manner, and the results are shown in Tables 1 and 2 below. For comparison, the apparatus shown in FIG. 8 has the same inclination as that of Comparative Example 1 so that the configuration is shared as much as possible except for characteristic portions.BoardWas attached.
<Device specifications>
  (Example 1)
  Flock formation tank: Square tube tank, effective capacity 36 liters, 200 mm x 1150 mmH (bottom 60 ° cone, inner cylinder 125 mmφ x 300 mmH)
  Precipitation tank: Square tube tank, effective capacity 87 liters, 200 mm x 2500 mmH (bottom 60 ° cone, top slope)BoardWith)
  (Comparative Example 1)
  Flock formation tank: square tube tank, effective capacity 36 liters, 200mm x 1000mmH
  Precipitation tank: Square tube tank, effective capacity 87 liters, 200 mm x 2500 mmH (bottom 60 ° cone, top slope)BoardWith)
<Test conditions>
  Flow rate: 1.6-2.4m^Three / H
  Precipitation tank LV: 40-60 m / h
  Inorganic flocculant: Polyaluminum chloride 15ppm
  Polymer flocculant: Polyacrylamide anionic polymer flocculant 1ppm
  Sand input amount: 750 g and 2000 g
[0082]
[Table 1]

[0083]
[Table 2]

  As can be seen from the results of Table 1, in Comparative Example 1, the sand concentration in the floc-forming tank was lower than that in Example 1, and it was recognized that this was due to the sediment of the sand in the lower part of the floc-forming tank. In addition, when the amount of sand input was large, the flocs became heavier, so that the amount of sedimentation was further increased.
[0084]
  Further, as can be seen from the results in Table 2, the turbidity of the treated water in the comparative example in which the sedimentation of the sand in the floc forming tank is large is poor, and the tendency is more when the sand input is 2000 g than when the sand input is 750 g. Remarkably appeared.
[0085]
  Furthermore, the sand concentration in the floc-forming tank when the sand input amount is 2000 g in Comparative Example 1 of Table 1 is higher than the sand concentration when the sand input amount is 750 g in Example 1, but the treated water. The water quality was worse in the case of Comparative Example 1, and the tendency for the water quality to deteriorate as the precipitation tank LV increased was increased.
[0086]
  From these results, it was confirmed that the method and apparatus of the present invention are effective for the coagulation precipitation treatment.
[0087]
【The invention's effect】
  According to the invention of each claim of the present application, the following effects are produced.
[0088]
  According to invention of Claim 1, since the to-be-processed water introduce | transduced into the tank of a flock formation process is made to flow in from the tank bottom part by an upward flow and a circulation flow is produced in this tank, it deposits in the bottom part of a flock formation tank The floc can be wound up by a circulating flow, and while maintaining a high flow rate, the suspension (SS) contained in the water to be treated and the added sand can be absorbed to grow into a floc having a large particle size. As a result, the amount of fine floc flowing into the precipitation separation tank can be reduced, and while maintaining a high flow rate of, for example, 50 to 150 m / h, most of the suspension (SS) has a large particle size and a sedimentation rate. As a large floc, it can be quickly settled and separated in a sedimentation tank, so that treated water having excellent water quality can be obtained.
[0089]
  According to the second aspect of the present invention, a floc that forms a circulating circulation including an upward flow from the bottom of the tank and winds down on the bottom can be wound up in the tank of the flock formation process. Since flocs that have absorbed SS and sand can be grown without incurring flocs sedimentation, for example, while passing water to be treated at a high flow rate of 50 to 150 m / h, fine flocs can be separated. The effect that the process which suppressed the outflow from a tank can be performed is show | played.
[0090]
  According to the invention of claim 3, the raw water (treated water) is introduced into the floc forming tank by an upward flow and the circulation flow of the treated water in the tank is simultaneously rectified. Thus, the circulation flow flow promoting action, the circulation flow rectification by the partition installed in the tank and the promotion action by the swirl blade device, etc. are combined, and the flow of the water to be treated in the tank of the floc forming treatment is more Large flocs that are more stable and have a high sedimentation rate grow well, and the amount of fine flocs transferred to the tank for precipitation separation can be reduced. Therefore, it is effective in improving the quality of treated water.
[0091]
  According to the fifth aspect of the present invention, the coagulation sedimentation treatment can be performed at a higher flow rate than in the prior art, or a large amount of raw water (treated water) can be treated with a small-scale facility.
[0092]
  According to the sixth aspect of the present invention, the flow of water to be treated in the floc forming tank is given by introduction of raw water, and a large floc that is likely to be deposited at the bottom is wound up by this introduced water, so that the floc may be deposited at the bottom of the tank. Can be reduced or eliminated, and the configuration therefor can be realized with a relatively simple structure.
[0093]
  According to the seventh aspect of the present invention, since the vertical flow path of the upward flow and the downward flow is partitioned by the flow path setting partition wall, the circulating and circulating flow flowing through each of the flow paths promoted by the flow promoting means Is reduced and the possibility of destroying the flocs is reduced, and the SS, sand or fine flocs are satisfactorily absorbed.
[0094]
  According to the eighth aspect of the present invention, since the direction of the flow of the water to be treated that moves and flows into the sedimentation tank beyond the overflow plate is guided downward, the tendency of the floc to settle and settle is increased, and at the same time, the small floc Can be suppressed from flowing toward the overflow device.
[0095]
  According to the ninth aspect of the present invention, the bulkheads are arranged in a meandering manner so that the large flocs are smoothly and rapidly settling upward, overflow, and downward (inflow into the settling tank), and the fine flocs move toward the water surface. The effect of reducing the transition tendency is achieved.
[0096]
  According to the invention of claim 10, the flow in the opposite direction is circulated in and out of the inner cylinder of the substantially double-cylindrical floc forming tank, and this flow is promoted by the flow promoting means such as the swirl blade device as a whole. A rectified flow can be formed, and floc winding and floc growth can be obtained well.
[0097]
  According to the eleventh aspect of the invention, the portion forming the second longitudinal flow path for the downward flow has an intermediate tank role before the transition of the water to be treated to the settling tank. The floc that may be deposited on the bottom of the partial flow path can be returned to the first vertical flow path that has the action of winding the floc in an upward flow. Can be wound up satisfactorily.
[0098]
  According to the twelfth aspect of the present invention, it is possible to smoothly flow the circulating flow that turns from the downward flow to the upward flow at the bottom of the floc forming tank, and to improve the floc winding while suppressing the breakage of the floc. It can be carried out.
[0099]
  According to the invention of claim 13, since the horizontal cross-sectional area is small at the bottom of the floc forming tank for winding up the floc, the flow velocity can be increased and the winding force can be increased, so that the floc can be prevented from being deposited more effectively. The effect is obtained.
[Brief description of the drawings]
FIG. 1 is a diagram showing a schematic configuration of an apparatus according to a first embodiment of the present invention.
FIG. 2 is a diagram showing a schematic configuration of an apparatus according to a second embodiment of the present invention.
FIG. 3 is a diagram showing a schematic configuration of an apparatus according to a third embodiment of the present invention.
FIG. 4 is an embodiment of the present invention.4The figure which showed the structure outline | summary of the apparatus of.
FIG. 5 is a diagram showing an example of a conventional coagulation precipitation apparatus.
FIG. 6 is a diagram schematically showing a problem in a case where the floc is transferred from the floc forming tank to the sedimentation tank by an overflow type.
FIG. 7 is another view schematically showing a problem in the case where the floc is transferred from the floc forming tank to the sedimentation tank by an overflow type.
8 is a view showing a coagulating sedimentation apparatus obtained by simplifying the apparatus of the third embodiment shown in FIG. 3 in order to perform a processing test (Example) of the present invention.
9 is a view showing a coagulating sedimentation apparatus in which the conventional apparatus of FIG. 5 is simplified in order to perform a comparative example in comparison with a processing test using the apparatus of FIG.
[Explanation of symbols]
1,11,12,13 ... Flock forming tank
  101, 111, 121, 131 ... trunk
  112 ... Intermediate trunk
  102, 113, 122, 132 ... cone part
  103, 114, 123 ... upper partition
  104, 115, 124 ... opening
  116: Channel setting partition( Guide wall)
  117 ... opening
2 ... Precipitation tank
  201 ... Overflow wall
  202 ... trunk
  203 ... cone part
  204 ... overflow
  205 ...Overflow water distributionGuide wall
3 ... Raw water (treated water) introduction pipe
4, 41, 42 ... swirl blade device
  401, 411, 421 ... motor
  402,403 ... swirl vanes
  404 ... Rotating shaft
5 ... InorganicAgglomerationAgent supply pipe
6 ... Polymer flocculant supply pipe
7 ... SandSupplyapparatus
  701 ... Pump
  702 Cyclone
  703: Sludge discharge pipe

Claims (13)

A floc-forming treatment in which flocs containing insoluble fine particles are grown while circulating the water to be treated containing a suspension (SS) and a chemical treatment agent necessary for floc formation and to which insoluble fine particles having a large specific gravity are added. And a precipitating treatment for precipitating and separating flocs containing insoluble fine particles and having a large sedimentation rate from water by the treatment, and an overflow plate for partitioning the floc precipitation separating tank from the floc-forming treatment tank. A coagulation sedimentation method in which the above treatments are sequentially performed in such a manner that the water to be treated is continuously overflowed on the top,
The flow of the water to be treated in the tank for performing the floc forming treatment is caused by flowing the water to be treated in an upward flow from the bottom of the floc forming tank, so that the floc that sinks to the bottom flows up by the upward flow. A method for coagulating and precipitating a suspension, characterized in that: A floc-forming treatment in which flocs containing insoluble fine particles are grown while circulating the water to be treated containing a suspension (SS) and a chemical treatment agent necessary for floc formation and to which insoluble fine particles having a large specific gravity are added. And a precipitating treatment for precipitating and separating flocs grown to have a large sedimentation rate and containing insoluble fine particles by the treatment from water, and an overflow plate for partitioning the floc precipitation separating tank from the floc-forming treatment tank. A coagulation precipitation method in which the treatment is sequentially performed so that the water to be treated overflows continuously at the upper part,
The circulating flow is turned to flow upward in the water to be treated along a flow path partitioned by a partition in the floc forming tank so as to wind up the floc that settles at the bottom of the tank. A method for coagulating and precipitating a suspension.   A method for coagulating and precipitating a suspension, which comprises the methods of claim 1 and claim 2 together.   4. The polymer agglomeration as another chemical treatment agent according to any one of claims 1 to 3, wherein an inorganic flocculant that is one of chemical treatment agents is added in advance to water to be treated that is introduced into a tank for flock formation treatment. A method for coagulating and precipitating a suspension, which comprises directly adding an agent and insoluble fine particles to the tank.   The method for coagulating and precipitating a suspension according to any one of claims 1 to 4, wherein an upward flow velocity of the fluid circulation flow applied to the bottom of the flock-forming tank is 50 m / h or more. A floc forming tank in which flocs containing insoluble fine particles are grown while circulating the water to be treated which contains a suspension (SS) and a chemical treatment agent necessary for floc formation and to which insoluble fine particles having a large specific gravity are added. And a floc sedimentation tank for precipitating flocs grown to have a large sedimentation rate containing insoluble fine particles by the treatment at the bottom of the tank and discharging the separated water from the upper part of the tank, and from the floc formation tank to the floc precipitation tank A coagulation sedimentation apparatus comprising an overflow channel that allows the treated water to flow over the upper part of the overflow plate provided to partition both tanks,
An apparatus for coagulating and precipitating a suspension, characterized in that a to-be-treated water introduction pipe for allowing the to-be-treated water to flow into the floc-forming tank is connected to the bottom of the tank. A floc forming tank in which flocs containing insoluble fine particles are grown while circulating the water to be treated which contains a suspension (SS) and a chemical treatment agent necessary for floc formation and to which insoluble fine particles having a large specific gravity are added. And a floc sedimentation tank for precipitating flocs grown to have a large sedimentation rate containing insoluble fine particles by the treatment at the bottom of the tank and discharging the separated water from the upper part of the tank, and from the floc formation tank to the floc precipitation tank A coagulation sedimentation apparatus comprising an overflow channel that allows the treated water to flow over the upper part of the overflow plate provided to partition both tanks,
In the flock forming tank, there is provided a flow path setting partition wall extending in a substantially vertical direction for defining a vertical flow path for upward flow and a vertical flow path for downward flow in the tank. And a treated water circulation flow turning section for providing flow promoting means for circulating and flowing the treated water from any one of the vertical flow paths to the other vertical flow path, and for turning a downward flow upward from the lower part of the partition wall. Is provided in the vicinity of the bottom of the tank.   8. The suspension according to claim 6 or 7, wherein the overflow channel has an overflow plate and a guide wall provided in the settling tank and guiding the overflow water downward into the settling tank. Coagulation sedimentation equipment.   In Claim 6 or 7, the overflow type flow path was entangled in an up-and-down meandering manner by the overflow plate and the overflow water distribution guide walls respectively provided in the flock formation tank and the sedimentation tank on both sides of the overflow plate. Constructed as a flow channel, the overflow water distribution guide wall on the flock forming tank is suspended from the water surface into the water to form a treated water inflow opening facing the flock forming tank at the middle position in the vertical direction of the flock forming tank An apparatus for coagulating and precipitating a suspension, characterized in that it is provided.   8. The flow path setting partition provided in the flock formation tank according to claim 6 or 7 is a vertically open cylindrical wall installed in the flock formation tank, and the flow that promotes the circulation flow inside the cylindrical wall. An apparatus for coagulating and precipitating a suspension, characterized in that an accelerating means is provided.   The floc forming tank according to claim 6 or 7, wherein the flock-forming tank includes a first longitudinal channel for an upward flow that is long in the vertical direction set by the channel setting partition wall, and an upper side of the first longitudinal channel. And a second vertical flow channel chamber for a short downward flow in the vertical direction divided by the flow channel setting partition wall, and an overflow channel from the second vertical flow channel. And a lower part of the second longitudinal channel is communicated with the first longitudinal channel so that the floc can be returned and circulated. Precipitation equipment.   An apparatus for coagulating and precipitating a suspension, characterized by having both the configuration of claim 6 and the configuration of any of claims 7 to 11.   The flocs forming tank according to any one of claims 6 to 12, wherein the shape of the vicinity of the bottom of the tank is provided in a cone shape in which the horizontal cross-sectional area decreases from the top to the bottom. Precipitation equipment.

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