JP6280110B2 - Digestive equipment - Google Patents

Description

  The present invention relates to a digester, and more particularly, to a digester that treats raw sludge, excess sludge, and raw garbage by methane fermentation in a digester of the digester.

  By using a carrier that supports anaerobic microorganisms in the digestion tank, anaerobic microorganisms can be retained in the digestion tank at a high concentration, so that a large amount of sludge collected by the sludge recovery device can be efficiently collected in a short residence time. Methane fermentation is possible, and there is an advantage that the generated methane gas can be recovered as energy.

  In Patent Document 1, an aerobic microorganism of a methanogen that contributes to methane fermentation is used in a digestion tank by using a non-woven carrier having a columnar shape and a substantially star-shaped cross section so that an appropriate flow action is obtained on the carrier surface. It is possible to maintain methane fermentation of raw sludge and garbage efficiently and stably with a short residence time.

  That is, in the digester, a large amount of raw sludge, surplus sludge and raw garbage can be efficiently methane-fermented in a small digestion tank, and temporarily by inflow of sewage into the wastewater treatment system or input of raw garbage. Even if the load fluctuates, raw sludge, surplus sludge and raw garbage can be stably subjected to methane fermentation. That is, an organic waste having a high solid matter concentration can be stably methane-fermented, and an organic waste methane fermentation treatment apparatus having a high processing capacity capable of making the entire system compact can be provided.

JP 2004-41929 A

  However, when the carrier necessary for the treatment is installed in the digester, most of the digester is occupied.

  In addition, fermentation sludge, etc., accumulates over time at the bottom of the digester, and undecomposed residues of organic waste with a relatively large particle size enter between the fibers of the carrier carrying anaerobic microorganisms. Therefore, there is a problem that the methane fermentation treatment capacity is gradually reduced, and it is necessary to appropriately stir the treatment liquid introduced into the digester and suppress the accumulation of sludge and the like.

  Therefore, a stirring device is required in the digestion tank, but it has been very difficult to achieve the above object by reducing how much energy is consumed by stirring.

  In the conventional stirring method, a draft tube is provided in the digestion tank, and a part of the digestion gas generated in the digestion tank is diffused into the digestion tank through the draft tube or processed in the digestion tank. A method such as circulating agitation equipment that draws a part of the liquid with a pump and supplies it to the digester again, or mixing the inside of the digester using a stirring blade was used. It was difficult to achieve the object with low power while giving an appropriate flow to the entire surface of the carrier.

  The present invention solves such problems, provides an appropriate flow velocity to the entire surface of the fixed carrier, maintains uniform mixing in the tank, and prevents sediment at the bottom of the digestion tank with extremely low power. It is intended to be realized.

To achieve the above object, the digester of the present invention, the inner wall of the bath, are respectively fixed by providing a clearance from the bottom and ceiling, and the solid support is a donut shape having a through hole overall shape extending in the vertical direction Rotation that is provided in the upper part of the fixed carrier and in the vicinity of the lower part of the liquid level and that rotates around the axis so as to generate a downward swirling flow in the gap between the inner wall of the tank and the fixed carrier. A blade, and a stationary blade that is provided so as to extend radially at the bottom of the tank and is formed so as to generate an upward flow in the through hole of the fixed carrier from the swirling flow .

It is a vertical side view of the digestion apparatus of Example 1 of this invention. It is a top view of this digestion apparatus. It is a BB line cross-sectional view of this digestion apparatus. It is a perspective view of the frame which fixes the support | carrier of this digestion apparatus. It is a top view of the support | carrier of this digester. It is an AA line longitudinal cross-sectional view of the support | carrier of this digester. It is explanatory drawing which shows the flow of the processing water in a processing tank.

  Examples of modes for carrying out the present invention will be described below.

  A first embodiment of the present invention will be described with reference to FIGS.

  2 shows the digester of the digester 1 of Example 1 of this invention, and this digester 2 is formed in the cylindrical shape of the vertical bottom.

  Reference numeral 3 denotes a fixed carrier, and the fixed carrier 3 is formed in a cylindrical shape (doughnut shape) extending in the vertical direction having a thick wall, and 3a extends in the vertical direction in the center of the fixed carrier 3. For example, a through hole having a circular cross section. In addition, the fixed carrier 3 is provided with a gap 6 between the digestion tank 2 and the inner wall 2a of the digestion tank 2 via the legs 4 and the arms 5 in the digestion tank 2, and In addition to being fixed coaxially, gaps 7 and 8 are provided and fixed between the bottom 2b and the ceiling 2c of the processing tank 2, respectively.

  As shown in FIGS. 4 to 6, the fixed carrier 3 forms a string-like body 9 by weaving a porous wire made of glass fiber, carbon fiber, synthetic resin, or the like, for example. 9 are extended in the vertical direction, and a plurality of them are spaced apart from each other and arranged densely, and one end and the other end of each string-like body 9 are connected to the upper frame portion 10a and the lower frame of the frame 10 as shown in FIG. Each of the body portions 10b is fixed to a horizontal rod body 10f, which will be described later, so that the overall shape is a substantially cylindrical shape (doughnut shape) having a through hole 3a at the center and extending in the vertical direction.

  In addition, the diameter (size) of the through hole 3a formed in the center is a size capable of forming a circulating flow in the digestion tank 2 with the gap 6 and the through hole 3a, as will be described later. . Further, the cross-sectional shape of the through hole 3a is not necessarily circular.

  Further, the fixed carrier 3 is preferably substantially cylindrical, but may be cylindrical such as polygonal or elliptical. Moreover, the notch part may be formed in the outer periphery shape of this fixed support | carrier 3 partially.

  Moreover, the space | interval (water flow path 14) of the said adjacent string-like body should just have the space | interval which produces an upward flow sufficiently short than the diameter of this through-hole 3a.

  In addition, as shown in FIG. 4, the said frame 10 connects the upper frame part 10a and the lower frame part 10b with the some vertical rod 10c. The upper frame portion 10a and the lower frame portion 10b include an outer ring body 10d, an inner ring body 10e coaxial with the outer ring body 10d, the outer ring body 10d and the inner ring body, respectively. It consists of a plurality of horizontal rods 10f that connect the torus 10e.

  In addition, you may comprise each said string-like body with a center string body and many loop-shaped wire rods or string bodies extended radially from this center string body.

  The fixed carrier 3 carries anaerobic microorganisms such as methane bacteria.

  Reference numeral 11 denotes a stationary blade, and the stationary blade 11 is formed of a linear belt-like plate, and is fixed to the bottom portion 2b in the digestion tank 2 in a radial manner coaxially with the fixed carrier 3, for example, four pieces, There is a gap 12 at the center of the bottom corresponding to the intersection of these strips.

  Reference numeral 13 denotes a rotating blade, and the rotating blade 13 is composed of, for example, four blades radially fixed to a lower end of a rotating shaft 13a coaxial with the carrier 3, and is formed on the upper portion of the digestion tank 2. It was made to rotate in the vicinity of the liquid level in the digestion tank 2 through the rotating shaft 13a by driving a fixed motor (not shown).

  Next, the operation and effect of the digester 1 of the present invention will be described.

  When the rotary blade 13 is rotated, as shown in FIG. 7, a downward swirling flow is generated in the gap 6 between the inner wall 2 a of the digestion tank 2 and the fixed carrier 3, and the inside of the through hole 3 a of the fixed carrier 3. Then, a gentle upward flow is formed and circulates in the digestion tank 2.

  In addition, a gentle upward flow is also generated in the water passage 14 formed between the string-like bodies 9 constituting the fixed carrier 3 and extending from the lower end surface of the fixed carrier 3 to the upper end surface thereof. An appropriate flow velocity is applied to the outer peripheral surface and the entire surface of the string-like body 9 constituting the fixed carrier 3.

  According to the digester of the present invention, even if the fixed carrier occupies most of the digester and the resistance of the liquid flow in the fixed carrier 3 is large, the gap 6 and the through-hole 3a of the fixed carrier 3 A circulation flow can be formed between them, and at the same time, an appropriate flow velocity is given also to the fixed carrier 3 through the water passage 14, so that this flow can improve the uniformity in the water tank 2, Operation with extremely low power is possible.

  Instead of fixing the string-like body 9 between the upper frame body portion 10a and the lower frame body portion 10b of the frame body 10, a string-like body is woven to form a nonwoven fabric-like body (not shown). The body is extended in the up and down direction, and a plurality of pieces are appropriately bent in a direction perpendicular to the up and down direction, spaced apart from each other and closely arranged, and one end and the other end of each non-woven body are connected to the upper frame body portion 10a. You may make it fix between the lower frame parts 10b, and may make it the substantially cylindrical shape (doughnut shape) extended in an up-down direction with the whole shape having the through-hole 3a in the center part.

  Even in this case, a circulation flow can be formed between the gap 6 and the through-hole 3a of the fixed carrier 3, and at the same time, a gentle rise is made through the water passage 14 formed between the nonwoven fabrics. A flow can occur.

  Further, the fixed carrier 3 may have a cylindrical shape extending in the vertical direction having a through hole in a central portion made of one glass fiber or carbon fiber. The fixed carrier 3 is preferably one having a plurality of water passages penetrating from the lower end surface to the upper end surface.

DESCRIPTION OF SYMBOLS 1 Digestion apparatus 2 Digestion tank 2a Inner wall 2b Bottom part 2c Ceiling part 3 Carrier 3a Through hole 4 Foot part 5 Arm part 6 Gap 7 Gap 8 Gap 9 String-like body 10 Frame 11 Stator blade 12 Gap 13 Rotary blade 13a Rotating shaft 14 Thread Waterway

Claims (4)

A fixed carrier that is fixed in a gap from the inner wall, bottom, and ceiling of the tank, and has a donut shape with a through hole extending in the vertical direction as a whole ;
A rotating blade provided at the upper part of the fixed carrier and in the vicinity of the lower part of the liquid surface , and configured to generate a downward swirling flow in the gap between the inner wall of the tank and the fixed carrier by rotating around the axis. When,
A stationary blade provided to extend radially at the bottom of the tank and formed to generate an upward flow in the through hole of the fixed carrier from the swirling flow;
A digestion apparatus comprising: The fixed carrier includes
The digestion apparatus according to claim 1, wherein a water passage that penetrates in a vertical direction is formed. The fixed carrier is
2. A plurality of string-like bodies extending in the vertical direction are arranged apart from each other and fixed by a frame so that the overall shape becomes a donut shape having a through-hole extending in the vertical direction. Digestive equipment. The fixed carrier is
2. A plurality of non-woven fabrics extending in the vertical direction are arranged apart from each other and fixed by a frame so that the overall shape becomes a donut shape having a through hole extending in the vertical direction. Digestive equipment.

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