JP4429970B2 - Rotating drum type solid-liquid separator - Google Patents

Description

  The present invention relates to a solid-liquid separator used in a sewage treatment plant and the like, and in particular, by introducing raw water to be treated (sewage containing solids such as scum impurities) into a rotating drum screen. The present invention relates to a rotary drum type solid-liquid separation device that separates raw water into solid and liquid components by filtering the components and further dewatering the residue (solid content) remaining after filtration through a dehydrator. .

  The rotary drum type solid-liquid separator is a unit in which a drum screen for filtration and a dehydrator are combined. FIG. 5 shows a general structure of a conventionally used rotary drum type solid-liquid separator (see Patent Document 1).

  As shown in the figure, a conventional rotary drum type solid-liquid separation device is rotated by a driving mechanism such as a motor 1, a raw water inlet pipe 3 for feeding raw water into the drum screen 2, and a raw water inlet pipe 3. A rectifying plate 4 attached to the tip of the slab, a filtrate collection chute 5 for collecting the liquid (filtrate) filtered by the drum screen 2, a filtrate collection tank 6 for storing the collected filtrate, and a liquid after filtration. A screw type dehydrator 7 for further dewatering the residue, a residue storage box 8 for storing the residue after dewatering, and the like are included.

  The drum screen 2 is a cage-shaped drum by arranging metal wires called wedge wires having a triangular cross section in a cylindrical shape along the axial direction of the drum with a slight interval of about 0.5 to 5 mm. Therefore, the liquid component is filtered by a minute gap formed between adjacent wedge wires 9, and the raw water is separated into a residue (solid content) and a liquid component.

  On the inner peripheral wall surface of the drum screen 2, a plurality of fin-shaped residue feeding blades 10 are erected with a predetermined inclination angle in the drum rotation axis direction, and the residue remaining after filtration. Is fed out toward the screw type dehydrator 7 by the residue feeding blade 10. A filtrate collection chute 5 is disposed below the drum screen 2, and the filtrate filtered by the drum screen 2 is collected by the filtrate collection chute 5 and stored in the filtrate collection tank 6, or drainage (not shown). It is discharged out of the system through the pipe.

  The screw type dehydrator 7 is located below the opening end of the drum screen 2. The residue sent by the residue feeding blade 10 is introduced into the residue input chute 7a of the screw type dehydrator 7 from the opening end of the drum screen 2 and is acted on by the screw 7c rotated by the motor 7b. While being sent toward the discharge port 7d, it is compressed and dehydrated in the meantime. The dewatered residue is dropped and stored in the residue storage box 8, and the dehydrated liquid is sent from the dehydrated liquid discharge port 7e to the filtrate collection tank 6 through a drain pipe (not shown) or discharged outside the system. It is what is done.

JP 2002-177712 (all pages, all figures)

  By the way, the above-described conventionally known rotary drum type solid-liquid separation device is such that when the operating time of the device becomes long, solid matter is caught between the gaps of the wedge wire 9, fibers or hairs get entangled, and further, the screen over time. Biofilms such as microorganisms may be generated on the inner and outer surfaces of the tube, causing clogging. If clogging occurs in the drum screen, the liquid content in the raw water cannot be sufficiently filtered, the liquid overflows and flows into the dehydrator together with the residue, and as a result, sufficient solid-liquid separation cannot be achieved. In addition, an excessive load is applied to the dehydrator, which may cause an abnormality or damage to the dehydrator.

  Conventionally, in order to prevent such clogging of the drum screen, a washing water jet nozzle is provided in the vicinity of the drum screen, and the screen surface is washed by spraying washing water at regular time intervals or at regular intervals. The device is stopped and the screen surface is manually cleaned. However, if clogging occurs during operation of the apparatus for some reason despite these cleaning processes, overflow of the liquid occurs as described above, and overflowed overflow water flows into the dehydrator.

  The present invention has been made to solve the above problems, and even when the drum screen is clogged, it is possible to take out only the residue in the raw water and send it to the dehydrator. An object of the present invention is to provide a rotary drum type solid-liquid separation device in which water does not flow into a dehydrator.

  In order to achieve the above object, the drum rotary solid-liquid separation device of the present invention supplies raw water to be treated into a rotating drum screen to filter the liquid, and further removes the residue remaining after the filtration. In the rotary drum type solid-liquid separation device that separates the raw water charged into solid and liquid by dehydrating it, it was inserted concentrically with the drum rotation shaft from the drum opening end toward the drum screen. Located around the raw water inflow pipe, a residue feeding screw provided with a spiral screw blade is provided concentrically and rotatably with respect to the raw water inflow pipe, and the residue feeding screw is connected and fixed to the drum screen. As a result, the residue feed screw rotates integrally with the drum screen around the raw water inflow pipe, and around the outer periphery of the rotating residue feed screw, Cover the lower half of the screw for cutting, and use a bowl-shaped draining trough with a semicircular cross section with a draining hole in the peripheral surface. On the inner peripheral surface of the drum screen at the drum opening end side, the drum screen is moved toward the drum opening end side at a position facing the draining trough, and the residue is scraped up into the draining trough. It is the one that is put up and the blades for residue cleaning are installed upright. It is desirable to provide an overflow receiver for recovering overflow water overflowing from the drum screen, located below the drum opening end of the drum screen.

  According to the rotating drum type solid-liquid separation device of the present invention having the above-described configuration, the drum screen is fed toward the drum opening end side, and the residue is scraped up with the blade for lifting up the residue and put into the draining trough. While draining the residue put in the draining trough and transporting it toward the drum opening end side by the residue feeding screw, the moisture in the residue is drained from the draining hole of the draining trough during this transfer. Since only the debris after being discharged is fed to the dehydrator, even if the drum screen is clogged, only the debris after being drained by the draining trough can be sent to the dehydrator. It is possible to perform solid and liquid separation work reliably.

  In addition, since the overflow water is not sent to the dehydrator as in the prior art, there is no excessive load on the dehydrator, and it is possible to prevent the occurrence or damage of the dehydrator due to overflow. it can.

  In addition, overflow water overflowing from the opening end side of the drum screen when clogging occurs can be collected and recovered in the overflow receiver, so that the inside of the device is not flooded with overflow water, improving safety. The maintenance and management of the device can be simplified.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 4 show an embodiment of a rotary drum type solid-liquid separator according to the present invention.
1 is a schematic cross-sectional view showing the configuration of the entire apparatus, FIG. 2A is a schematic cross-sectional view taken along line AA in FIG. 1, and FIG. 2B is a schematic cross-sectional view taken along line BB in FIG. FIG. 3 is a perspective view of a screw for feeding residue, and FIG. 4 is a perspective view of a draining trough. In addition, the same code | symbol was attached | subjected and shown to the part same as a conventional apparatus (FIG. 5).

  The rotary drum type solid-liquid separator according to this embodiment is a rotary drum type solid-liquid separator having the same structure as the conventional one, and is positioned around the raw water inflow pipe 3 as shown in FIGS. In addition, a spiral feed screw 11 is provided concentrically and rotatably with respect to the raw water inflow pipe 3, and the lower half portion of the residue feed screw 11 is covered to have a semicircular cross section. A water draining trough 13 is arranged. The raw water inflow pipe 3 is inserted from the drum opening end side into the drum screen 2 so as to be concentric with the rotating shaft of the drum screen 2, and is fixedly arranged by a fixing mechanism (not shown).

  The residue feeding screw 11 arranged rotatably around the raw water inflow pipe 3 has a structure as shown in FIG. 3, and the outer peripheral surface of the tubular body 11b is formed by welding a spiral screw blade 11a. It is fixed. The raw water inflow pipe 3 penetrates the inside of the tubular body 11 b concentrically and is inserted in a loose fit state, and the residue feeding screw 11 can freely rotate around the raw water inflow pipe 3.

  The residue feeding screw 11 rotatably arranged around the raw water inflow pipe 3 is attached to the peripheral edge of the screw blade 11a at a predetermined interval (120 degree interval in the illustrated example) at the end on the rectifying plate 4 side. A predetermined number (three in the illustrated example) of mounting arms 12 a, 12 b, and 12 c are connected and fixed to the inner wall surface of the drum screen 2. As the drum screen 2 rotates, the residue feeding screw 11 is also connected to the drum screen 2. It is configured to rotate together around the raw water inflow pipe 3.

  A draining trough 13 is fixedly disposed around the outer periphery of the residue feeding screw 11 so as to cover the lower half of the screw. In the case of the illustrated example, the draining trough 13 includes, as shown in FIG. 4, a bowl-shaped portion 13 c having a semicircular cross section by cutting out the upper half of the cylindrical cylindrical body 13 b on the drum screen inner side. Thus, a large number of drain holes 13a are formed in the hook-shaped portion 13c. Although the hole diameter of the draining hole 13a is appropriately selected according to the size and type of contents contained in the raw water to be treated, for example, when the raw water to be treated is general household wastewater, the diameter It is about 2-8 mm. The hole 13d formed in the end surface of the cylindrical body 13b is an insertion hole for allowing the raw water pipe 3 to pass through.

  The draining trough 13 is configured to remove the residue that has been scraped into the draining trough 13 by the later-described residue lifting blade 14 and transfer it toward the screw-type dehydrator 7 by the action of the residue-feeding screw 11. During the transfer, excess water in the residue from the drain hole 13a is solid-liquid separated and drained, and the inner peripheral surface of the bowl-shaped portion 13c having the drain hole 13a formed therein is removed. The screw blade 11a is disposed so as to cover the lower half of the residue feeding screw in a state where it is slidably contacted with the periphery of the screw blade 11a or a slight gap is provided between the periphery of the screw blade 11a.

  At the lower surface near the outer end of the cylindrical body 13b of the draining trough 13, the residue after solid-liquid separation pushed out by the residue feeding screw 11 is directed to the residue input chute 7a of the screw type dehydrator 7. And a residue discharge port 13e is formed.

  In the case of the illustrated example, the draining trough 13 is placed on a fixed base such as a base 16 (see FIG. 1) and fixedly arranged at a fixed position using a metal band 17 or the like.

  On the other hand, inside the drum screen 2, as in the conventional apparatus, a fin-shaped blade feed blade 10 is provided upright with a predetermined inclination angle with respect to the drum rotation shaft, and further, a drum is provided. On the opening end side, a fin-shaped and dust cleaning blade 14 is erected in parallel with the rotation axis of the drum screen 2 at a position facing the draining trough 13.

  The screen scraping blade 14 scoops the screen residue transferred toward the drum opening end by the screen feed blade 10 and scrapes it upward according to the rotation of the drum screen 2 to a predetermined height. At this point, the scraped residue is dropped into the draining trough 13 by its own weight.

  An overflow receiver 15 is provided below the opening end side of the drum screen 2. The overflow receiver 15 is used to collect and discharge the overflow water from the system through a drain pipe (not shown) when the drum screen 2 is clogged and overflow water overflows into the drum screen 2. It is.

Next, the operation of the rotating drum type solid-liquid separator having the above-described configuration will be described.
First, a normal operation in which the drum screen 2 is not clogged will be described.

  When the process is started, the motor 1 is driven, whereby the drum screen 2 starts rotating at a predetermined speed. Along with the rotation of the drum screen 2, the residue feeding screw 11 that is integrally connected and fixed to the drum screen 2 by the mounting arms 12 a to 12 c starts to rotate together around the raw water inflow pipe 3.

  In this state, when the raw water to be treated is fed from the raw water inflow pipe 3, the fed raw water is fed into the drum screen 2 from the rectifying plate 4 provided at the tip of the raw water inflow pipe 3.

  The residue in raw water thrown into the drum screen 2 is sent toward the drum opening end side (left side in the example of FIG. 1) by the action of the rotating feed blade 10. During the transfer, the liquid contained in the raw water is filtered through the gap of the wedge wire 9, and only the solid residue remains in the drum screen 2.

  The residue remaining after filtration is further transferred toward the drum opening end by the residue feeding blade 10. On the other hand, the filtrate is collected in the filtrate collection tank 6 by the filtrate collection chute 5 at the bottom of the drum screen, or is discharged out of the system through a drain pipe (not shown).

  When the residue sent by the residue feeding blade 10 reaches the position of the residue lifting blade 14 which is erected on the drum opening end side, the received residue is scooped by the residue cleaning blade 14. It is taken up and scraped upward according to the rotation of the drum screen 2.

  When the residue reaches a predetermined height, the residue is slid down from the residue cleaning blade 14 by its own weight, and enters the draining trough 13. It falls and throws in.

  The residue dropped into the draining trough 13 is transferred toward the screw-type dehydrator 7 by the rotating residue-feeding screw 11, and the screw-type dehydrator 7 is fed from the residue discharge port 13e. It is put into the residue throwing chute 7a and fed into the screw type dehydrator.

  The residue fed into the screw dehydrator 7 is compressed and dehydrated while being sent toward the residue discharge port by the action of the screw 7c that is rotationally driven by the motor 7b. The dewatered residue is dropped and accommodated in the residue storage box 8 from the residue discharge port 7d, and the dehydrated water is sent from the dehydrated solution discharge port 7e to the filtrate recovery tank 6 through the drain pipe, Or it is discharged out of the system.

Next, the operation when the drum screen 2 is clogged will be described.
When the drum screen 2 is clogged, as described above, the drum screen 2 cannot sufficiently filter the liquid in the raw water. The rotary drum type solid-liquid separation device of the present invention removes the liquid in the raw water as follows even when such clogging occurs in the drum screen 2, and only the residue is transferred to the screw type dehydrator 7. Can be sent.

  That is, when clogging occurs in the drum screen 2, the liquid content in the raw water is filtered by the wedge wire 9 according to the degree of clogging at that time. Therefore, the drum screen 2 has more liquid and residue than usual. The liquid residue and residue are sent toward the drum opening end side by the residue feeding blade 10 and scraped one after another by the residue lifting blade 14 in the same manner as in the normal operation described above. Fried and put into the draining trough 13.

  The residue put in the draining trough 13 is sent toward the drum opening end side by the residue transfer screw 11, but excess moisture that could not be sufficiently filtered by the drum screen 2 is transferred to the drainage trough 13. The solid is separated from the drainage trough 13a of the draining trough 13 and drained to a moisture content of about the same level as in the normal filtration by the drum screen 2.

  The residue drained by the draining trough 13 is introduced into the residue throwing chute 7a of the screw type dehydrator 7 from the residue discharge port 13e in the same manner as in the normal time, and is discharged by the screw type dehydrator 7 in the same way as in the normal time. Dehydrated and separated into solid and liquid.

  On the other hand, the moisture returned from the drain hole 13a into the drum screen 2 is pushed toward the drum opening end by the residue feeding blade 10 while being filtered by the clogged wedge wire 9 according to the degree of clogging. Moisture that cannot be filtered and remains until the end is discharged as overflow water from the drum opening end toward the overflow receiver 15 and is discharged outside the system through a drain pipe (not shown).

  Thus, in the case of the rotating drum type solid-liquid separation device of the present invention, even when clogging occurs in the drum screen 2, solid-liquid separation can be performed in the same manner as when clogging does not occur, It is possible to eliminate the situation where the overflow water flows into the screw type dehydrator 7 as in the prior art.

  In addition, the said embodiment shows an example of this invention and this invention is not limited to the said embodiment.

  For example, in the above embodiment, the screw type dehydrator 7 is used as the dehydrator, but other dehydration type dehydrators may be used. Further, the drum screen 2 in which the wedge wires 9 for filtration are arranged in parallel along the direction of the axis of rotation of the drum and formed into a cylindrical shape has been described as an example. A drum screen (see FIGS. 3 and 7 of Patent Document 1) proposed in Document 1 is used by arranging the wedge wires in a ring shape along the circumference or spirally winding the wire around the circumference. You can also.

  Further, the diameter of the drain hole 13a formed in the drain trough 13 is not limited to one type. For example, the drain hole near the trough bottom is set to a small hole diameter, and the hole diameter increases toward the upper side of the trough side. The hole diameter may be changed depending on the location. Further, the hole shape of the draining hole 13a is not limited to a circular shape, and an arbitrary hole shape such as an oval shape, an oval shape, or a rectangular shape may be used, or these may be combined.

  Furthermore, in the said embodiment, although the draining trough 13 was mounted and fixed on the base 16, it is not restricted to this, For example, you may fixly arrange in the raw | natural water inflow pipe 3 concentrically. In short, it is only necessary that the draining trough 13 can be fixedly disposed so that the inner peripheral surface thereof is in sliding contact with the residue feeding screw 11 or can be in a fixed position with a slight gap.

1 is a schematic cross-sectional view showing an embodiment of a rotary drum type solid-liquid separator according to the present invention. (A) is AA schematic sectional drawing in FIG. 1, (b) is BB schematic sectional drawing in FIG. It is a perspective view of a screw for feeding residue. It is a perspective view of a draining trough. It is a schematic sectional drawing of the conventional rotary drum type solid-liquid separator.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Motor 2 Drum screen 3 Raw water inflow pipe 4 Rectification plate 5 Filtrate collection chute 6 Filtrate collection tank 7 Screw type dehydrator 7a Slag loading chute 8 Slag receiving box 9 Wedge wire 10 Slag feed blade 11 Slag feed screw 11a Screw blade 11b Tubular body 11b Raw water inflow pipe insertion hole 12a to 12c Mounting arm 13 Drain trough 13a Drain hole 13b Cylindrical body 13c Saddle-shaped part 13d Raw water pipe insertion hole 13e Screen discharge port 14 Scouring blade 15 Overflow receptacle 16 Base for fixing draining trough 17 Metal band for fixing draining trough

Claims (2)

The raw water to be treated is put into a rotating drum screen, the liquid is filtered, and the residue remaining after filtration is further dehydrated through a dehydrator to separate the raw water input into a solid and a liquid. In the rotating drum type solid-liquid separator
Positioned around the raw water inflow pipe that is inserted concentrically with the drum rotation shaft from the drum opening end side into the drum screen, the residue feed screw with spiral screw blades is connected to the raw water inflow pipe. Are concentric and rotatable,
By connecting and fixing the residue feeding screw to the drum screen, the residue feeding screw rotates integrally with the drum screen around the raw water inflow pipe,
On the outer periphery of the rotating screw for feeding residue, a bowl-shaped draining trough covering the lower half of the residue feeding screw and having a semicircular cross section with a draining hole in the peripheral surface is provided. Place it in sliding contact with the feed screw or fix it with a slight gap,
On the inner peripheral surface on the drum opening end side of the drum screen, the drum screen is transported toward the drum opening end side at a position facing the draining trough, and the residue is scraped up and put into the draining trough. A rotating drum type solid-liquid separator characterized by erection blades for scumming.   2. The rotary drum type solid-liquid separation device according to claim 1, wherein an overflow receiver for recovering overflow water overflowing from the drum screen is provided below the drum opening end of the drum screen.

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