JP3871440B2 - Concentrated agglomeration reactor - Google Patents

Description

【００１９】
実施例の処理成績の平均値は、処理速度；９．０ｍ³ ／時間、分離水ＳＳ濃度；２２４ｍｇ、濃縮汚泥度；３２．９ｇ／リットルで、６０日以上の連続運転が可能であった。処理水ＳＳ濃度の平均値が数百ｍｇ／リットル以下である点から濃縮分離が非常に良好に行われているといえる。
【００２０】
【発明の効果】
本発明の濃縮型凝集反応装置においては、凝集反応用の撹拌機以外の駆動装置を用いず、簡単な構造のもので、分離用スリットの凝集ペレットによる目詰まりが起きにくく、濃縮・分離の効率が良いとともに、１次側スクレ−パの摩耗が少なく、長時間連続して安定した濃縮効率を維持することができる。
【図面の簡単な説明】
【図１】本発明の濃縮型凝集反応装置の概念縦断面図である。
【図２】図１の濃縮型凝集反応装置の要部概念平面図である。
【図３】（ａ）は本発明の１次側スクレ−パのフリ−辺の正面図であり、（ｂ）はその線Ａ−Ａについての水平断面図である。
【図４】従来の典型的なスクリ−ンの概略図である。
【図５】従来の濃縮型凝集反応装置の概念図である。
【符号の説明】
１ スクリ−ン
２ ウェッジワイヤ−
３ スリット
４ サポ−トバ−
５ ブラシ
６ ブラシの毛
７ 濃縮型凝集反応装置
８ 汚泥供給管
９ ポリマ−供給管
１０ 濃縮汚泥流出管
１１ 分離水流出管
１２ 凝集反応槽
１３ 駆動装置
１４ 撹拌羽根
１５ テレスコ−プ弁
１６ シャフト
１７ ドラフトチュ−ブ
１８ 二重スクレ−パ
１９ スクリ−ン
２０ １次側スクレ−パ
２１ ２次側スクレ−パ
２２ ゴムライニング
２３ ヒンジ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an agglomeration reaction apparatus used for concentrating / separating suspended substances from sludge and wastewater, and in particular, a concentration type agglomeration reaction apparatus capable of simultaneously performing an agglomeration reaction and an agglomerated product concentration / separation. It is about.
[0002]
[Prior art]
In order to separate suspended substances from sludge and wastewater, first, the suspended substances etc. are agglomerated from the wastewater by the coagulation method, and the aggregated pellets are separated by solid-liquid separation. If they are provided apart from each other, the pellets may be broken while the aggregated pellets are transferred from the aggregator to the solid-liquid separator. Therefore, it is preferable to use a concentrated agglomeration reactor of the type incorporating the solid-liquid separator. Usually, the concentration type agglomeration reaction apparatus is provided with a slit-type solid-liquid separation device usually in the shape of a screen for concentration separation.
Conventionally, when agglomerating pellets aggregated in a reaction tank of the apparatus when agglomerated pellets are aggregated and separated in a reaction tank of the apparatus by agglomerating sludge or suspended solids in waste water using a concentration type agglomeration reactor, Grows to about 10 mm. The liquid to be treated containing such agglomerated pellets passes through the slit of the screen for concentration in the reaction tank, so that part of the separated water is discharged out of the system, and the suspension contains the agglomerated pellets. (Processed liquid) is concentrated.
[0003]
FIG. 5 is a longitudinal sectional view conceptually showing a typical concentration type agglomeration reaction apparatus. The processing of the liquid to be processed by the concentration type agglomeration reaction apparatus will be described below with reference to FIG.
In FIG. 5, the concentrated agglomeration reactor 7 has a vertical cylindrical shape, a sludge supply pipe 8 and a polymer supply pipe 9 on the lower side surface of the reactor 7, and a concentrated sludge outflow pipe 10 on the upper side surface. The separated water outflow pipes 11 are connected to the side surfaces. A driving device 13 is provided above the reaction device 7, and this driving device 13 rotates a stirring blade 14 and a scraper 18 attached to a shaft 16 for stirring the inside of the aggregation reaction tank 12 of the reaction device 7. As shown in FIG. 4, the screen 19 having a slit for separating the separated water has a ring-shaped wedge wire-2 placed horizontally and stacked in the vertical direction at intervals of 1 mm, for example. -The structure fixed by Toba-4. This structure will be described in detail later.
[0004]
There is a draft tube 17 for increasing the upward flow velocity on the surface of the screen 19 at the center in the tank 12. While the sludge as the liquid to be treated is stirred by the stirring blade 14 and lifted up to the position of the screen 19 by the draft tube 17, suspended substances in the liquid are aggregated, and the aggregated pellets are screened 19. Since the separated water that has been separated into the solid and liquid through the slit 19 goes out, the concentration of the suspension in the tank 12 increases, and the concentrated sludge (including the coagulated pellets) is concentrated in the sludge outflow pipe. 10, the separated water is discharged from the separated water outflow pipe 11 to the outside of the system. The separated water naturally flows down, and the flow rate is controlled by the telescoping valve 15.
[0005]
As described above, the agglomerated product containing the agglomerated pellets (hereinafter referred to as “aggregated pellets”) usually stays in the tank for several minutes while being stirred with a water flow by a stirrer or the like disposed in the apparatus, Like the concentrated sludge, it is transferred to the next step as a coagulated concentrate. However, if the agglomerated pellets in the agglomeration reaction tank stay in the reaction vessel and adhere to and accumulate on the screen separation slit, preventing the separation liquid from flowing out, the effective separation area of the slit will decrease. Concentration efficiency decreases. For this reason, usually, the cross flow velocity on the slit surface is increased or a scraper or a brush is used in the vicinity of the slit surface to prevent adhesion and accumulation of the agglomerated pellets. Since these slit clogging prevention mechanisms are desirable to obtain an effect without providing a new driving device for the simplification of the device structure, there may be a simple structure using the driving force of the stirrer in the tank. Many.
[0006]
However, the effects of these simple clogging prevention mechanisms vary greatly depending on the properties of the aggregated product. Specifically, when the viscosity of the agglomerated pellets and the separated water, the particle size and shear strength of the agglomerated pellets are different, the degree of adhesion of the agglomerated product to the slit surface and clogging of the slits differs, and the prevention mechanism is different. There are cases where it works and cases where it does not. For example, when the particle size and shearing force of the agglomerated pellets are both relatively large, such as sludge generated at a sewage treatment plant or activated sludge treatment facility, the conventional slit clogging prevention mechanism is sufficient, The waste liquids of factories that handle the material have a very small particle size, and the shear force of the aggregated pellets may be extremely small, and some of the aggregated pellets may break and clog the slits. Therefore, a clogging prevention mechanism using a crossflow water flow or a scraper may be insufficient in effect. That is, it can be said that there were very few concentrated agglomeration reactors having a simple structure that completely prevented clogging of the separation slits such as factory waste liquid.
[0007]
FIG. 4 shows an example of the screen of the screen type solid-liquid separation apparatus used in the aggregation reaction tank of the conventional concentration type aggregation reaction apparatus. The screen 19 shown in FIG. 4 has a structure in which a ring-shaped wedge wire-2 is horizontally leveled and overlapped at an interval of 1 mm in the vertical direction and fixed by a support bar 4 extending in the vertical direction. Therefore, a slit is formed between the wedge wires-2. When the agglomerated product containing the agglomerated pellets is solid-liquid separated with such a screen 19, it adheres and accumulates on the separation slit of the screen 19, and the outflow of the separated liquid is prevented. In order to easily and effectively prevent such clogging of the slit in the screen 19 by using the driving force of the stirrer of the agglomeration reaction apparatus, a brush 5 disposed inside the screen 19 is installed. The technology to do was proposed. However, if a gap is provided between the tip of the brush bristles 6 and the support bar 4 of the screen 19, clogging is often not completely prevented. However, if the tip of the brush bristles 6 penetrates the slits, the brush bristles 6 will not return to the bent state due to the operation for a long time, and the gaps between the wedge wires 2 constituting the slit 3 will not be returned. There is a problem in that the clogged aggregated product cannot be scraped out by the brush bristles 6.
[0008]
Further, as described above, when sludge is supplied to the inside of the screen 19 (the one where the workpiece enters is referred to as “primary side”), and a brush is provided on this side, in the case of processing by the so-called inner stroke method There is a problem that scum accumulates on the separated water side outside the screen 19 (this is called “secondary side”). This can be prevented by arranging and rotating a scraper having an L-shaped cross section on the separated water side, but in this case, there is a problem that it is not possible to remove polymer or sludge that is sticky on the primary side. . When this scraper is rotated, a phenomenon occurs in which the water level is high in the traveling direction and the water level is low in the rear. Thus, even if the brush 19 or the scraper is provided on the primary side or the secondary side of the screen 19, clogging of the slit of the screen 19 cannot be prevented sufficiently.
[0009]
[Problems to be solved by the invention]
The present invention solves the above-mentioned problems of the prior art, incorporates a mechanism that completely prevents clogging of the separation slit with a simple structure without using a drive device other than a stirrer for agglomeration reaction. It is an object of the present invention to provide a concentration type agglomeration reaction apparatus that makes it possible to maintain stable concentration efficiency.
[0010]
[Means for Solving the Problems]
The present invention has solved the above problems by the following means.
(1) In a concentration type agglomeration reaction apparatus in which a concentration screen is arranged that enables the liquid to be treated to be aggregated and concentrated in a single device, the shape of the concentration screen is cylindrical. , The direction of the slits of the concentration screen is horizontal, and the shaft of the mixer for mixing in the tank rotates along the vicinity of both the primary and secondary sides of the slit of the concentration screen. by arranging path into position for removing the aggregate product to be clogged in the slit eyes respectively, the concentration for subscription - - rotated relative to emissions, secondary Sucre - pa it passes Sucre to When the separation water is pressed against the secondary side surface of the slit, the separation water flows backward on the slit surface and pushes the aggregated product clogged into the slit side to the primary side, The adhered agglomerated product is slipped. A concentration type agglomeration reaction apparatus characterized by having a mechanism for removing the agglomerated product by floating from the surface .
(2) The scraper has a shape in which one side of a flat plate with a thickness of less than 10 mm with a primary side scraper applied with a rubber lining is fixed by a hinge and the opposite side moves freely, and the primary side of the slit A scraper that rotates while being in contact therewith, and a secondary-side scraper has a shape in which a flat bar or an angle bar has a predetermined inclination, and is provided with a predetermined interval from the slit surface. The concentrated agglomeration reaction apparatus according to the above (1), which acts so that the separated water on the secondary side flows back from the secondary side of the slit by the scraper.
[0011]
(3) The concentration type according to (1) or (2), wherein the length of the primary side scraper in the vertical direction is from the uppermost slit in the screen to the vicinity of the upper end of the in-vessel draft tube. Aggregation reactor.
(4) The primary-side scraper is installed so as to be positioned 10 to 300 mm behind the secondary-side scraper relative to the traveling direction of the circular motion of the scraper. The concentration type agglomeration reaction apparatus according to any one of (1) to (3).
[0012]
DETAILED DESCRIPTION OF THE INVENTION
More specifically, in order to solve the above-mentioned problems, the present invention provides a support in which wedge wires are ring-shaped in a concentration type agglomeration reactor and overlapped at intervals of several millimeters and these are passed in the vertical direction. A cylindrical concentrating screen is formed by fixing with a bar, and slits are formed between each wedge wire and a support bar. Combining a scraper that has a rubber lining that moves circularly while making contact with the slit on the side surface, and a scraper that moves circularly with a predetermined inclination around the secondary surface of the slit at a predetermined interval. A method using a double scraper is employed (see FIGS. 1 and 2).
[0013]
The slit clogging prevention mechanism will be described in detail with reference to the drawings. As shown in FIGS. 1 and 2, the double scraper is formed by joining separate scrapers 20, 21 on the primary side and the secondary side of the slit surface. When a part of the aggregated product concentrated in the tank is likely to be clogged on the primary side of the slit, the secondary scraper 21 of the double scraper becomes the primary scraper 20. The circular motion is preceded in the traveling direction of the circular motion, and when the secondary scraper 21 passes, the separated water near the scraper is pressed against the secondary side surface of the slit. As a result, the separated water momentarily flows backward on the slit surface and pushes the aggregated product clogged into the slit back to the primary side, and the aggregated product adhering to the primary side of the slit surface moves from the slit surface toward the center of the tank. Float up for a moment. The inclination of the scraper and the gap between the scraper and the surface on the secondary side of the slit are set so as to increase the instantaneous backflow effect. The primary-side scraper 20 that runs after a predetermined interval immediately after the agglomerated product floats for a moment is in physical contact with the primary side of the slit on the surface of the rubber lining 22, The agglomerated product can be completely peeled from the primary surface of the slit.
[0014]
As shown in the figure, the primary side scraper 20 has one side fixed by a hinge 23 and the opposite side is free. Since the scraper 20 is circularly moved in the concentration tank, the scraper 20 is always pressed against the slit surface by the moment applied by the centrifugal force of the scraper 20 and the concentrated sludge in the tank. The scraper 20 preferably has a thickness of less than 10 mm in order to reduce the resistance received from the concentrated sludge by circular motion. The tip of the scraper 20 is cut into a taper shape to reduce the resistance. When the draft tube 17 is present in the tank, the length of the scraper 20 in the vertical direction is preferably from the uppermost slit to the vicinity of the upper end of the draft tube 17. Since there is a draft tube 17, the upward flow from the uppermost slit to the draft tube 17 is small, so the slit is easily clogged in this range. The upward flow is large from the upper end to the lower end of the draft tube 17, and the clogging of the slit is small even without the scraper 20. The rubber lining 22 of the scraper 20 is desirably made of a material having excellent wear resistance. By adopting the double scraper as a clogging prevention mechanism, the aggregated product is continuously removed from the slit surface, and it becomes possible to suppress an increase in filtration resistance before and after the slit. The device can be operated continuously and stably.
[0015]
Next, a preferred embodiment of the concentration type agglomeration reaction apparatus incorporating the concept of the present invention will be described in detail. 1 and 2, the same parts as those shown in FIGS. 4 and 5 are denoted by the same reference numerals.
FIG. 1 is a longitudinal sectional view conceptually showing a concentration type agglomeration reaction apparatus. The shape of the reactor 7 is a vertical cylindrical shape, and the concentrated sludge outflow pipe 10 is connected to the middle side surface, the separated water outflow pipe 11 is connected to the middle side surface, the sludge supply pipe 8 and the polymer supply pipe 9 are connected to the lower side surface. . There is a draft tube 17 for increasing the upward flow velocity on the surface of the screen 19 at the center of the tank. The separated water flows down naturally, and the flow rate is controlled by the telescoping valve 15. There is a driving device 13 at the upper part of the tank, and this driving device 13 rotates the stirring blade 14 for stirring the inside of the tank and the double scraper 18 existing on both the primary side and the secondary side of the slit. The screen 1 for separating the separated water has a ring-shaped wedge wire-2 placed horizontally and stacked in a vertical direction at intervals of 1 mm. Each wedge wire-2 is fixed by a vertical support bar-4.
[0016]
The primary-side scraper 20 is provided with a special rubber-based lining having an overall thickness of 9 mm and excellent wear resistance. The length of the scraper 20 in the vertical direction was set to the same height as the upper end of the draft tube 17. The secondary scraper 21 was arranged with a 35 mm gap from the slit surface with the angle made of stainless steel facing the corner toward the center of the tank. Details of the contact portion of the primary scraper 20 with the slit are shown in FIG.
[0017]
【Example】
Hereinafter, specific examples will be shown in order to deepen the understanding of the present invention, but the present invention is not limited to the specific examples shown below.
Example 1
The test was conducted using a 500-liter capacity concentrated agglomeration reactor of the present invention having the configuration described with reference to FIG.
The target sludge used was a special wastewater SS concentration of Y food factory; 90-20.0 g / liter. The sludge was agglomerated with a polymer agglomerated polymer in the tank to form agglomerated pellets. The wastewater from this Y food factory was much finer in the size of the agglomerated pellets compared to activated sludge generated from a normal wastewater treatment plant, and the particle size was about 3 to 4 mm. The rate of addition of polymer per sludge to TS was 0.9% (wt). The average amount of inflow sludge was 9 m ³ / hour, and the separation water was half that of 5 m ³ / hour. Under these conditions, 24-hour continuous operation was performed for about 2 months. The processing results are shown in Table 1.
[0018]
[Table 1]

[0019]
The average value of the treatment results of the examples was a treatment speed of 9.0 m ³ / hour, a separation water SS concentration of 224 mg, a concentrated sludge degree of 32.9 g / liter, and continuous operation for 60 days or more was possible. It can be said that the concentration and separation are performed very well since the average value of the treated water SS concentration is several hundred mg / liter or less.
[0020]
【The invention's effect】
The concentration type agglomeration reaction apparatus of the present invention has a simple structure without using a drive device other than an agitation stirrer, and is less likely to be clogged by the agglomerated pellets of the separation slit. In addition, the wear of the primary side scraper is small, and stable concentration efficiency can be maintained continuously for a long time.
[Brief description of the drawings]
FIG. 1 is a conceptual longitudinal sectional view of a concentration type agglomeration reaction apparatus of the present invention.
2 is a conceptual plan view of a main part of the concentrated agglomeration reaction apparatus of FIG. 1. FIG.
FIG. 3A is a front view of the free side of the primary scraper of the present invention, and FIG. 3B is a horizontal sectional view of the line AA.
FIG. 4 is a schematic view of a typical conventional screen.
FIG. 5 is a conceptual diagram of a conventional concentrated agglomeration reaction apparatus.
[Explanation of symbols]
1 Screen 2 Wedge wire
3 Slit 4 Support bar
5 Brush 6 Brush Hair 7 Concentrated Coagulation Reactor 8 Sludge Supply Pipe 9 Polymer Supply Pipe 10 Concentrated Sludge Outflow Pipe 11 Separated Water Outflow Pipe 12 Coagulation Reaction Tank 13 Drive Unit 14 Stirring Blade 15 Telescope Valve 16 Shaft 17 Draft Tube 18 Double scraper 19 Screen 20 Primary side scraper 21 Secondary side scraper 22 Rubber lining 23 Hinge

Claims (4)

In a concentration type agglomeration reaction apparatus in which a concentration screen is arranged, which enables the liquid to be treated to be aggregated and concentrated in a single device, the shape of the concentration screen is cylindrical, and the concentration is performed The direction of the slits of the screen is horizontal, and the shaft rotates around the both sides of the primary side and the secondary side of the slit of the concentrating screen on the shaft of the mixing mixer in the tank. Each of the rollers is disposed at a position to remove the aggregated product clogging the slits, and is rotated relative to the concentration screen. When the secondary scraper passes, By pressing the separated water in the vicinity of the scraper against the secondary side surface of the slit, the separated water flows backward on the slit surface and pushes the aggregated product clogged into the slit back to the primary side and adheres to the primary side of the slit surface. Agglomerated product is slit surface A concentration type agglomeration reaction apparatus characterized by having a mechanism for removing the agglomerated product by floating from the surface.   The scraper has a shape in which one side of a flat plate having a thickness of less than 10 mm with a primary side scraper having a rubber lining is fixed by a hinge and the opposite side moves freely, and contacts the primary side of the slit. The scraper that rotates while the secondary side scraper has a flat bar or angle bar with a predetermined inclination, and is disposed at a predetermined interval from the slit surface. 2. The concentration type agglomeration reaction apparatus according to claim 1, wherein the concentrated agglomeration reaction apparatus acts so that the separated water on the secondary side flows back from the secondary side of the slit by the scraper by the rotation.   The concentrated agglomeration reaction apparatus according to claim 1 or 2, wherein the length of the primary side scraper in the vertical direction is from the uppermost slit in the screen to the vicinity of the upper end of the in-vessel draft tube.   2. The primary-side scraper is disposed so as to be positioned 10 to 300 mm behind the secondary-side scraper relative to the direction of travel of the scraper's circular motion. The concentration type agglomeration reaction apparatus according to any one of to 3.

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