JP2014144407A - Drainage treatment apparatus and method for operating the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drainage treatment apparatus capable of efficiently producing biogas from the wastewater in wet refuse pulverization treatment in a simple way.SOLUTION: A solid-liquid separation tank 2 is provided to receive the wastewater in wet refuse pulverization treatment for settling separation. A liquid phase anaerobic fermentation part 5 is provided to produce biogas from organic materials contained in the liquid phase, and a sediment anaerobic fermentation tank 3 is provided to produce biogas from sediment. An advection part 26 is disposed to advect the sediment from the solid-liquid separation tank 2 to the sediment anaerobic fermentation tank 3. A choking part 26a is disposed to block the advection part 26 with sediment for prevention of backflow. A sediment advection mechanism is disposed to advect the sediment to the sediment anaerobic fermentation tank 3 through the choking part 26a and to return the excess liquid phase to the solid-liquid separation tank 2 through the choking part 26a. A biogas discharging passage 32 is disposed to discharge the produced biogas outside.

Description

  The present invention relates to a waste water treatment apparatus for purifying garbage pulverization waste liquid and an operation method thereof.

  In recent years, garbage disposers tend to be widely used in households and apartment houses for the purpose of reducing the volume of garbage, etc., and there is a tendency to install wastewater treatment equipment that can treat garbage that has been crushed by the disposer. It is in.

  As a form of such a wastewater treatment apparatus, a configuration in which the waste pulverization waste liquid is simply solubilized by anaerobic treatment, and purified water is obtained by aerobic treatment of the solubilized liquid phase is realistic. Garbage that cannot be completely solubilized is separated into solid and liquid, composted, converted into feed, and excess solid components are incinerated.

  However, in this type of treatment, composted and feedd garbage is reused, but it is difficult to say that energy is effectively used for parts that are incinerated. Since it is an aerobic treatment, a large amount of dilution water is required, so it cannot be said that it is a very efficient treatment method. Furthermore, there is a limit to the reuse of the composted and feed energy, and a technology for biogas conversion that can be used for general purposes is desired.

  As described in Patent Document 1, as a technology for converting the waste pulverization waste liquid into biogas, the wastewater obtained by pulverizing the waste is solubilized and anaerobic fermentation is performed on the solubilized components to recover methane gas. A processing device is considered.

  However, these wastewater treatment apparatuses require time for solubilization and a large solubilization tank or anaerobic fermentation tank because the waste pulverization waste liquid cannot be subjected to anaerobic fermentation unless it is sufficiently solubilized. Furthermore, it is known that methane bacteria grow slowly in an anaerobic fermenter, and it is necessary to suppress the outflow of methane bacteria when the treated liquid after anaerobic fermentation is taken out. Therefore, it was not possible to always maintain a continuous state between the tanks, and it was preferable to configure each tank from individual water treatment containers. Moreover, in order to transfer treated water between each tank, a large-scale pump is required as power. As a result, the wastewater treatment apparatus requires a large-scale apparatus configuration.

JP 2002-119937 A

  Therefore, when the above-described wastewater treatment apparatus is downsized and simplified, it is necessary to simplify the transfer of the waste pulverization treatment waste liquid to the anaerobic fermentation tank.

  In order to improve the efficiency of transferring the waste pulverization treatment waste liquid to the anaerobic fermentation tank, it is desirable to realize a configuration capable of continuous advection of the waste pulverization treatment waste liquid. Moreover, in an anaerobic fermenter, in order to improve the processing efficiency of a solid component, the anaerobic fermenter which can hold | maintain the high concentration methane bacteria which can be anaerobically fermented even if it is a solid component which is not solubilized is comprised. And the methane bacteria retained in the anaerobic fermenter need to be maintained through continuous processing.

  Therefore, in view of the above situation, an object of the present invention is to provide a wastewater treatment apparatus capable of biogasification of garbage pulverization wastewater simply and efficiently.

[Configuration 1]
The characteristic configuration of the wastewater treatment apparatus of the present invention for achieving the above object is as follows:
Provided with a receiving portion for receiving the waste pulverization waste liquid, and a solid-liquid separation tank for separating and separating the waste pulverization waste liquid,
While providing a liquid phase anaerobic fermentation section for biogasification of organic matter contained in the liquid phase solid-liquid separated in the solid-liquid separation tank,
A precipitate anaerobic fermenter that accepts the precipitate separated in the solid-liquid separation tank and converts it to biogas,
Provided with an advection section for advancing sediment from the solid-liquid separation tank to the sediment anaerobic fermentation tank,
It is possible to prevent the reverse flow of the solid component from the precipitate anaerobic fermentation tank to the solid-liquid separation tank by closing the space between the solid-liquid separation tank and the precipitate anaerobic fermentation tank at the transfer section. While providing a throttle part to
The precipitate is transferred to the precipitate anaerobic fermenter via the constriction, and the excess liquid phase of the precipitate anaerobic fermenter can be returned to the solid-liquid separation tank via the constriction. A mechanism is provided in the precipitate anaerobic fermenter,
The liquid phase anaerobic fermentation section and the precipitate anaerobic fermentation tank are provided with a biogas extraction path for taking out the generated biogas to the outside.

[Operation effect 1]
According to the above configuration, the waste water treatment apparatus accepts the garbage pulverization treatment waste liquid, and separates the garbage pulverization treatment waste liquid into the solid-liquid separation tank, and the solid-liquid separated precipitate is a precipitate anaerobic fermentation tank. The biogasification treatment can be carried out by transferring the wastewater, and the bacterial cell concentration can be maintained at a high concentration, and the waste pulverization waste liquid purified by the biogasification treatment can be drained. In addition, the liquid phase that has been subjected to solid-liquid separation has been anaerobically fermented, and the assimilated organic matter has been converted to biogas so that the organic components contained in the garbage can be recovered more efficiently as energy.

Specifically, the waste pulverization waste liquid is solid-liquid separated in a solid-liquid separation tank and separated into a supernatant and a precipitate. The sediment settles and reaches the constriction in the advection section. In the throttling part, the space between the solid-liquid separation tank and the precipitate anaerobic fermentation tank is blocked by the precipitate, so that backflow of solid components from the precipitate anaerobic fermentation tank to the solid-liquid separation tank can be prevented. Since the sediment advancing mechanism is provided, the sediment is transferred from the solid-liquid separation tank to the sediment anaerobic fermentation tank in one way. On the other hand, the liquid phase containing the supernatant in the solid-liquid separation tank is anaerobically fermented in the liquid phase anaerobic fermentation unit to produce biogas. Moreover, the sludge which consists of the microorganisms of the said precipitate anaerobic fermenter is hold | maintained within a precipitate anaerobic fermenter, and is hold | maintained without flowing out outside. That is, depending on the flow rate of the excess liquid phase, the liquid phase returns from the precipitate anaerobic fermentation tank to the solid-liquid separation tank, but the precipitate exhibits a filter effect and the precipitate anaerobic fermentation. Anaerobic microorganisms contained in the return flow from the tank remain in the precipitate. Thereby, the anaerobic microorganism density | concentration in the said precipitate anaerobic fermenter can be maintained at a high density | concentration. And, in the precipitate anaerobic fermentation tank, the precipitate in the solid-liquid separation tank flows, but the solid components inside the precipitate anaerobic fermentation tank are not returned to the solid-liquid separation tank, and the precipitate anaerobic tank Operation in which microorganisms in the fermenter are prevented from flowing out of the sediment anaerobic fermenter and reduced, good anaerobic fermentation can be maintained, and sediment corresponding to the amount of solid components reduced by anaerobic fermentation is sequentially replenished The state can be maintained.
Therefore, the deposit anaerobic fermentation tank can be continuously gasified and reduced by anaerobic fermentation and biogas can be recovered simply by adopting a sediment advection mechanism with a simple configuration.

  Thereby, it was possible to provide a wastewater treatment apparatus that can efficiently convert the liquid phase and the precipitate obtained by solid-liquid separation of the waste pulverization waste liquid into a biogas efficiently.

  The biogas produced in the precipitate anaerobic fermenter is taken out from the biogas take-out path and can be supplied as a fuel for gas engines, boilers, etc., or as a raw material for synthesis of various chemical substances.

[Configuration 2]
In addition, the liquid phase anaerobic fermentation unit may be configured by providing a carrier for growing anaerobic microorganisms in a region where the liquid phase stays inside the solid-liquid separation tank.

[Operation effect 2]
The liquid-phase anaerobic fermentation unit decomposes organic components contained in the liquid phase obtained by solid-liquid separation of the waste pulverization waste liquid into biogas, and thus holds a sufficient amount of anaerobic microorganisms growing in the liquid phase. Therefore, it is considered that the efficiency of biogasification can be improved by improving the efficiency of contact with the liquid phase. Therefore, if a carrier for growing anaerobic microorganisms is provided in the region where the liquid phase stays inside the solid-liquid separation tank, the contact efficiency between the carrier and the liquid phase is increased while the microorganisms are retained on the carrier. As a result, extremely high biogasification efficiency can be exhibited. Since the liquid phase anaerobic fermentation unit further decomposes the organic substance which has been anaerobically decomposed in the precipitate anaerobic fermenter to lower the molecular weight, the effect of completely decomposing the precipitate in two stages can be exhibited. The carrier used in the liquid phase anaerobic fermentation unit may be a fluid carrier using a plurality of spherical or cylindrical resins, or a fixed carrier using a columnar or plate-like resin.

  Therefore, the waste pulverization waste liquid can be converted into biogas more completely and recovered as energy.

[Configuration 3]
In addition, the liquid phase anaerobic fermentation section includes a water treatment tank that receives the liquid phase transferred from the solid-liquid separation tank, and is provided with a carrier for growing anaerobic microorganisms in the water treatment tank. May be.

[Operation effect 3]
As described in the above configuration, high biogasification efficiency can be exhibited by bringing the microorganisms held on the carrier into contact with the liquid phase. However, if the carrier is arranged and held in the liquid phase region inside the solid-liquid separation tank, there is an advantage that it can be arranged in a space-saving manner, but in some cases, a solid-liquid separated precipitate that cannot accommodate a sufficient amount of carrier. If an object adheres to the carrier, it may be difficult to maintain high biogasification efficiency over a long period of time. In such a case, the solid-liquid separation tank is provided with a water treatment tank that receives the liquid phase transferred from inside the solid-liquid separation tank, and a carrier for growing anaerobic microorganisms is provided in the water treatment tank. Biogasification of the waste grinding treatment waste liquid can be achieved in a sufficiently large water treatment space separate from the separation layer, and a high load treatment can be performed according to the properties of the waste grinding treatment waste liquid.

  Therefore, particularly when the load is high, such as when the waste pulverization waste liquid has a very high concentration, it is preferable because high biogasification efficiency can be maintained over a long period of time.

[Configuration 4]
The constriction section includes a slit-shaped outlet provided in the lower part of the solid-liquid separation tank, and is configured such that a deposit in the solid-liquid separation tank can be deposited by closing the slit-shaped outlet.

[Operation effect 4]
According to the above configuration, the sediment that has settled in the lower part of the solid-liquid separation tank collects in a lower concavity at the slit-shaped outlet, and is therefore dammed and deposited at the slit-shaped outlet. Then, the deposit deposited at the slit-shaped outlet flows back from the precipitate anaerobic fermentation tank to the solid-liquid separation tank with respect to the precipitate and solid components such as microorganisms in the precipitate anaerobic fermentation tank. It will function as a filter that prevents this.

  Then, with the simple configuration of damming the precipitate using the slit-shaped outlet as a throttle, the precipitate gradually flows into the precipitate anaerobic fermentation tank, while the solid components from the precipitate anaerobic fermentation tank Backflow can be prevented. Thereby, while maintaining the amount of sediment in the said sediment anaerobic fermentation tank suitably, the microorganisms in a sediment anaerobic fermentation tank can be reliably hold | maintained in a tank, and generation | occurrence | production of biogas can be maintained favorable.

[Configuration 5]
In addition, an air diffuser that diffuses anaerobic gas is provided in the precipitate anaerobic fermenter, a gas supply device that intermittently supplies anaerobic gas to the air diffuser is provided, and air that rises from below the slit-shaped outlet is provided. The precipitate advection mechanism may be formed by arranging so as to form a liquid mixed phase flow.

[Operation effect 5]
According to the said structure, the gas-liquid mixed phase flow which rises from the downward direction of the said slit-shaped exit can be formed by aeration of the anaerobic gas in the said precipitate anaerobic fermenter by the said aeration apparatus. When the gas-liquid mixed phase flow rises in the vicinity of the slit-shaped outlet, an ejector effect due to the flow of the mixed-phase flow occurs, and the sediment that has been dammed to the slit-shaped outlet is moved to the precipitate anaerobic fermentation tank side. It functions as a sediment advancing mechanism that sucks out and advancing from the solid-liquid separation tank to the precipitate anaerobic fermentation tank. Moreover, since it is anaerobic gas supplied to the said diffuser at this time, the anaerobic fermentation conditions of the said precipitate anaerobic fermenter can be maintained favorable. As such an anaerobic gas, the biogas produced | generated in the said precipitate anaerobic fermenter can be utilized, for example.

  Therefore, the sediment advection mechanism can be configured with a simple configuration, and the solid-liquid can be simply controlled by adjusting the amount of air diffused from the air diffuser and the timing of the air diffused. The amount of sediment transferred from the separation tank to the precipitate anaerobic fermentation tank can be controlled.

[Configuration 6]
In addition, a solubilization tank for solubilizing the waste pulverization treatment waste liquid received by the receiving unit is provided, and a convection section for transferring the solubilized garbage pulverization treatment waste liquid from the solubilization tank to the solid-liquid separation tank is provided. There may be.

[Operation effect 6]
According to the above configuration, the waste pulverization waste liquid separated by solid-liquid separation in the solid-liquid separation unit is received in the receiving unit, and then stored in the solubilization tank and solubilized in the solid-liquid separation tank. Inflow. Then, the amount of the precipitate separated and solid-liquid separated in the solid-liquid separation tank and transferred to the precipitate anaerobic fermentation tank is adjusted according to the solubilization degree of the waste grinding treatment waste liquid in the solubilization tank. By appropriately setting the amount of precipitate transferred from the liquid separation tank to the precipitate anaerobic fermentation tank, the wastewater treatment can be continued without hindering smooth anaerobic fermentation in the precipitate anaerobic fermentation tank.

[Configuration 7]
Moreover, you may provide the aerobic processing tank which receives the advection of the liquid phase isolate | separated by the said solid-liquid separation tank, and aerobically processes.

[Operation effect 7]
According to the above-described configuration, the liquid phase portion of the waste crushing waste liquid that has passed through the solid-liquid separation tank is mainly a waste liquid that has not been subjected to anaerobic treatment, and thus is expected to have a relatively high BOD. . However, it is possible to reduce the BOD by further aerobic treatment and to purify the water quality so that it can be discharged into the natural environment. Since it can be set as the structure which can be utilized also as a household septic tank etc. by setting it as a possible structure, it is preferable.

  In addition, if a return unit is provided for returning the sludge generated in the aerobic treatment tank to the solid-liquid separation tank, the sludge is further transferred to the precipitate anaerobic fermentation tank and can be decomposed in the precipitate anaerobic fermentation tank. Therefore, the amount of extracted sludge can be greatly reduced as the whole waste water treatment apparatus.

[Configuration 8]
Further, in the case where a sediment advection mechanism is provided with a gas supply device that supplies gas to the aeration device, the gas supply is performed according to the amount of decrease that is reduced with the biogasification of the precipitate in the precipitate anaerobic fermentation tank. The operation method of the waste water treatment apparatus which supplies the gas by an apparatus can be performed.

[Operation effect 8]
According to the above method, in the precipitate anaerobic fermenter, an amount of precipitate suitable for biogasification treatment is accommodated in the precipitate anaerobic fermenter and can be converted into biogas by anaerobic fermentation. In addition, the amount of the sediment deposited by the squeezing portion is appropriately maintained, and the sediment advection by the sediment advancing mechanism can be smoothly maintained.

  Therefore, it has become possible to provide a wastewater treatment apparatus that is small and can efficiently convert the waste pulverization waste liquid into biogas. This has made it possible to contribute to volume reduction of waste, effective use of renewable energy, and reduction of carbon dioxide generation.

It is a cross-sectional top view of the waste water treatment equipment of the present invention. It is the II-II line vertical front view in FIG. III-III line longitudinal front view in FIG. IV-IV line longitudinal side view in FIG. VV line vertical side view in FIG. VI-VI line vertical side view in FIG. The figure which shows the biogas generation amount in the sediment anaerobic fermentation tank in the waste water treatment equipment of this invention The figure which shows the biogas generation amount in the wastewater treatment equipment of the comparative example The figure which shows the biogas generation amount in the liquid phase anaerobic fermentation tank in the waste water treatment equipment of this invention Cross-sectional plan view of a wastewater treatment apparatus according to another embodiment of the present invention XI-XI line longitudinal front view in FIG. The principal part vertical side view of the waste water treatment equipment by another embodiment of the present invention

  Below, the waste water treatment apparatus of this invention is demonstrated. Preferred embodiments are described below, but these embodiments are described in order to more specifically illustrate the present invention, and various modifications can be made without departing from the spirit of the present invention. However, the present invention is not limited to the following description.

[Wastewater treatment equipment]
As shown in FIGS. 1 to 6, the wastewater treatment apparatus of the present application partitions the interior of the wastewater treatment apparatus main body A by partition walls W12, W13, W23, W25 to store the storage tank 1, the solid-liquid separation tank 2, and the sediment. An anaerobic fermenter 3 and a liquid phase anaerobic fermenter 5 are formed, and a receiving part 11 for receiving the waste pulverization waste liquid, and advection parts 14 and 26 (see FIG. 5) for transferring the processing liquid between the tanks, 52, 53 is formed.
Moreover, the biogas extraction path 32 (refer FIG. 3) which collect | recovers the biogas generated from the solid-liquid separation tank 2, the sediment anaerobic fermentation tank 3, and the liquid phase anaerobic fermentation tank 5 is provided. As a result, the waste grinding waste liquid is precipitated and separated, then the precipitate is anaerobically fermented in the sediment fermenter, and the liquid phase is anaerobically fermented in the liquid-phase anaerobic fermenter internal space as the liquid-phase anaerobic fermentation section. After being converted into biogas, the waste water is discharged from the drainage unit 24 to the outside of the wastewater treatment apparatus main body A as clean wastewater.

  Specifically, as shown in FIG. 1, the interior of the waste water treatment apparatus main body A is partitioned into two in the length direction by a partition wall W12, one space is used as a storage tank 1, and the other space is partitioned by a partition wall W23. , W25 are further divided into three in the width direction, the central space is formed in the solid-liquid separation tank 2, and the remainder is formed as a precipitate anaerobic fermentation tank 3 and a liquid-phase anaerobic fermentation tank 5. Here, the upper part of the precipitate anaerobic fermentation tank 3 is configured such that the gas generated in the precipitate anaerobic fermentation tank 3 is taken out from the biogas extraction path 32, and the liquid phase is transferred from this tank to another tank. It does not leak.

[Reservoir]
As shown in FIG. 1 to FIG. 6, the storage tank 1 includes a receiving portion 11 that receives the waste grind processing waste liquid in the vicinity of the liquid surface inside the waste water treatment apparatus main body A, and has a garbage shatter treatment discharge inside. A storage space 12 capable of storing the liquid is formed. In addition, an aeration pipe 13 for supplying anaerobic gas by the agitation pump P1 is provided inside the storage space 12, and aerated and agitated from the lower part of the storage tank 1, thereby storing the received garbage pulverization treatment waste liquid, It is configured so as to function as a solubilization tank for further solubilization and fluidization.

  At the upper end of the partition wall W12 that partitions between the storage tank 1 and the solid-liquid separation tank 2, the solubilized solubilized liquid of the waste pulverization treatment waste liquid is transferred to the solid-liquid separation tank 2 by overflow. The advection part 14 is provided (refer FIG. 2, FIG. 4). Moreover, the partition wall W13 which partitions between the said storage tank 1 and the said sediment anaerobic fermentation tank 3 is airtightly connected to the upper surface of the waste water treatment apparatus main body A (refer FIG. 3, FIG. 4).

[Solid-liquid separation tank]
As shown in FIGS. 1, 2, and 5, the solid-liquid separation tank 2 includes a guide wall portion 21 that guides the solubilized liquid received from the advection portion 14 downward in the waste water treatment apparatus main body A. A precipitation separation space 22 is formed that allows the solid component to be separated from the solubilized liquid guided downward by the guide wall 21. In addition, an aeration pipe 23 for supplying anaerobic gas by an agitation pump P4 is provided in the upper part of the precipitation separation space 22 (slightly above the lower end of the guide wall 21 in the drawing). The solubilized supernatant in the interior of the container is stirred to further purify it (see FIGS. 1 and 2).

  Further, between the solid-liquid separation layer and the liquid-phase anaerobic fermentation tank 5, a transfer pipe 52 as a transfer section for transferring the liquid phase obtained by solid-liquid separation of the waste pulverization waste liquid to the liquid-phase anaerobic fermentation tank 5. And a transfer pipe 53 (see FIG. 6) composed of a gas lifter functioning as a convection section into which the liquid phase subjected to the anaerobic fermentation treatment in the liquid-phase anaerobic fermentation tank 5 flows.

  A drainage portion 24 for discharging the treated wastewater to the outside of the wastewater treatment device main body A is provided on the opposite side of the receiving portion 11 in the solid-liquid separation tank 2, and the drainage portion 24 of the drainage treatment device main body A has an inner wall portion. A separation wall portion 25 is provided in the vicinity to suppress the mixing of solid components into the discharged wastewater to be discharged, and a clean supernatant liquid that does not contain solid components is discharged (see FIG. 2).

  As shown in FIG. 2 and FIG. 5, in the lower part of the solid-liquid separation tank 2, the precipitate separated from the solid component in the solid-liquid separation tank 2 is combined with the solubilized liquid in the precipitate anaerobic fermentation tank 3. A convection section 26 is provided that allows the effluent (excess liquid phase) that has been anaerobically treated in the precipitate anaerobic fermentation tank 3 to be returned to the solid-liquid separation tank.

  The advection part 26 is composed of an inclined wall part 26b provided with a slit-like outlet 26a as a throttle part provided at the lower part of the solid-liquid separation tank 2. The inclined wall portion is closer to the lower part of the solid-liquid separation tank as the lower part of the partition wall W23 is lowered, and a slanted outlet 26a is formed between the inner wall surface of the waste water treatment apparatus A. Inclined. As a result, the advancing of the precipitate, the solubilized liquid, and the treated waste water is suppressed via the slit-shaped outlet 26a, and the sediment in the solid-liquid separation tank closes and deposits the slit-shaped outlet 26a. The deposited layer 26c can be formed (see FIG. 5).

  In the above configuration, the width of the slit-shaped outlet 26a is about 10-30 mm, preferably about 15 mm.

  In addition, the partition wall W23 which partitions the said solid-liquid separation tank 2 and the sediment anaerobic fermentation tank 3 is airtightly connected to the upper surface of the waste water treatment apparatus main body A (refer FIG. 2, FIG. 5).

[Precipitate anaerobic fermentation tank]
As shown in FIGS. 1, 3, and 5, the sediment anaerobic fermentation tank 3 biodegrades the sediment received from the advection section 26 by anaerobic fermentation by methane bacteria in the waste water treatment apparatus main body A. An anaerobic fermentation space 31 is formed. The upper space of the anaerobic fermentation space 31 forms an airtight space surrounded by the liquid phase containing the precipitate, the partition walls W13 and W23, and the inner wall of the waste water treatment apparatus main body A, and the biogenerated in the anaerobic fermentation space 31 A biogas collection space for collecting gas is formed.

  In the methane gas collection space, a biogas extraction path 32 for taking out the collected biogas to the outside is provided. The biogas extraction path 32 is provided with a biogas tank T, which temporarily stores the collected biogas and can supply it to the outside as needed.

  The anaerobic fermentation space 31 is provided with an aeration device 33 that diffuses anaerobic gas, an aeration pump P3 as a gas supply device that intermittently supplies the anaerobic gas to the aeration device 33, and the slit shape. A sediment advancing mechanism that arranges the gas-liquid mixed phase flow that rises from below the outlet 26 a so as to form, and transfers the precipitate from the solid-liquid separation tank 2 to the precipitate anaerobic fermentation tank 3 via the transfer section 26. Is formed. In this example, biogas generated in the precipitate anaerobic fermentation tank 3 is used as the anaerobic gas.

  The sediment advection mechanism is configured to supply a large amount of bubbles at a time from the slightly lower side of the slit-like outlet 26a by the air diffuser 33, thereby ejecting the solid-liquid separation tank 2 by the ejector effect caused by the upward flow of the bubbles. The sediment deposited on the slit-shaped outlet 26a is sucked into the sediment anaerobic fermenter 3 side, and the deposit is transferred. At this time, the deposit in the deposited layer 26c deposited on the slit-shaped outlet 26a does not all flow at the same time, but always flows so that the deposited layer 26c of sediment is maintained in the slit-shaped outlet 26a. To do. Therefore, even if the precipitate is transferred from the solid-liquid separation tank 2 to the precipitate anaerobic fermentation tank 3 via the transfer section 26, the liquid phase in the precipitate anaerobic fermentation tank 3 is immediately Although it does not flow back to the separation tank 2, it is gradually returned to the solid-liquid separation tank 2 through the deposited layer 26c. Here, the advection part 26 also functions as a advection part for advancing the waste grinding waste liquid solubilized in the solid-liquid separation tank 2 from the sediment anaerobic fermentation tank 3. On the other hand, the solid components in the sediment anaerobic fermentation tank 3 cannot be transferred to the solid-liquid separation tank 2 due to the accumulation layer 26c. As a result, in the precipitate anaerobic fermentation tank 3, the precipitate in the solid-liquid separation tank 2 flows in, but the solid components inside the precipitate anaerobic fermentation tank 3 are not returned to the solid-liquid separation tank 2. , The microorganisms in the sediment anaerobic fermentation tank 3 are prevented from flowing out of the sediment anaerobic fermentation tank 3 and reduced, and a favorable anaerobic fermentation can be maintained. It is possible to maintain an operation state in which things are replenished sequentially. Therefore, in the precipitate anaerobic fermentation tank 3, the precipitate can be continuously gasified and reduced by anaerobic fermentation to recover biogas, and the purified liquid phase is returned to the solid-liquid separation tank 2, It becomes the structure discharged | emitted from the solid-liquid separation tank 2 outside.

  In addition, in the case of the said structure, since the aeration by the aeration apparatus 33 supplies a part of collected biogas with the aeration pump P3 from the said biogas tank T, the inside of the said precipitate anaerobic fermentation tank 3 is the inside. , Maintained in an anaerobic state. Furthermore, if a large amount of aeration of about 70 L / min is performed for about 20 seconds about twice a day, the advection of the precipitate according to the processing capacity of the precipitate anaerobic fermentation tank 3 can be continued. It is possible to efficiently transfer the precipitate derived from the pulverized food waste without using a capacity pump or the like.

[Liquid phase anaerobic fermentation tank]
As shown in FIGS. 1 and 6, the liquid phase anaerobic fermentation tank 5 is defined in the internal space of the waste water treatment apparatus main body A, and the liquid phase separated in the solid-liquid separation tank 2 is separated from the solid phase. It is received in the water treatment space 51 from the inflow pipe 52 provided in the upper part of the liquid separation layer.
The liquid phase anaerobic fermenter 5 is provided with a separation wall portion 54, and a water treatment space 51 and a pumping space 56 are formed therein. In the water treatment space, the anaerobic fermentation treatment is performed on the liquid phase. The anaerobic filter bed 55 is provided with a large number of carriers 55a for growing sexual microorganisms, and the organic matter contained in the liquid phase is transferred as the liquid phase received from the upper part of the water treatment space 51 is moved downward. By contacting with the carrier 55a, it is configured to be anaerobically fermented and biogasified. The liquid phase that has flowed downward and anaerobically fermented flows from the lower portion of the separation wall portion 54 to the pumping space 56. Biogas is supplied to the lower part of the vertical pipe 53a of the transfer pipe 53 from the gas lifter pump P2, and the liquid phase transferred to the pumping space 56 is returned to the solid-liquid separation tank 2 by the gas lifter action. It has become.

  Note that the solid-liquid separation tank, the sediment anaerobic fermentation tank, and the liquid-phase anaerobic fermentation tank each have an upper space formed in an airtight manner and communicate with each other, and the biogas staying in the upper space is supplied to the biogas extraction path 32. Is easily formed through

[Water treatment performance]
In the sediment anaerobic fermentation tank 3 in the wastewater treatment apparatus, the amount of solid components and the amount of biogas generated were examined, and the result was as shown in FIG. From FIG. 7, it can be seen that in the wastewater treatment apparatus having the above configuration, biogas is stably generated, and the solid component amount (TS) in the sediment anaerobic fermentation tank 3 is also stably reduced. . Moreover, the biogasification rate of the precipitate in the precipitate anaerobic fermentation tank 3 was about 45%.

  On the other hand, when it is set as the structure which does not provide the slit-shaped exit 26a as a throttle part in the said solid-liquid separation tank 2 (the solid-liquid separation tank 2 and the sediment anaerobic fermentation tank 3 are the slit-shaped exit 26a as a throttle part. When the amount of solid components and the amount of biogas generated in the sediment anaerobic fermenter 3 in the wastewater treatment device (comparative example) in the case of communication without being interposed are examined, the result is as shown in FIG. From FIG. 8, biogas is generated in the initial stage of operation in which methane bacteria are charged, but the outflow of solid components to the outside of the tank is severe, and the initial amount of solid components decreases to almost 0 after about 50 days. Thereby, even if the methane bacteria are replenished in the sediment anaerobic fermentation tank 3 (70 days, 170 days, and 220 days in the figure), the methane bacteria flow out of the tank and no biogas is generated. It was found that it can hardly contribute to the generation of biogas.

When the COD load and the tCOD decomposition rate of the liquid phase anaerobic fermenter 5 were examined over time under the conditions of an input load of 10 to 20 kg CODcr / m ³ / d and a residence time of 1 day, it was as shown in FIG. It was found that the decomposition rate was maintained at 80% to 90% regardless of the fluctuation of the load, and high biogasification was stably performed even in the liquid phase.
Moreover, when the time-dependent change was investigated about the quantity of non-sedimentation SS and sCOD (soluble COD) in the liquid phase anaerobic fermentation tank 5, it became like FIG.9 (b), ie, the organic substance contained in a liquid phase It can be seen that it has undergone anaerobic fermentation efficiently and has been purified.
Furthermore, when the relationship between the COD input amount and the biogas generation amount was examined, it was as shown in FIG. 9C, and the liquid phase biogasification rate was as high as 75%. I understood.
Therefore, the biogasification rate for the waste grinding treatment waste liquid of the wastewater treatment apparatus of the present invention is:
It was revealed that the processing efficiency was extremely high at (45+ (100−45) * 0.75 =) 86%.

[Another embodiment]
In the above embodiment, the purified supernatant is configured to flow directly out of the waste water treatment apparatus from the solid-liquid separation tank 2, but as shown in FIGS. 10 and 11, further inside the waste water treatment apparatus, An aerobic treatment tank 4 is formed, and the waste water overflowing from the solid-liquid separation tank 2 is transferred to the aerobic treatment tank 4 for further aerobic treatment and purified to a water quality level that can be discharged into the natural world. It can be used as a possible domestic septic tank.

  Specifically, in the configuration shown in FIG. 10 and FIG. 11, the solid-liquid separation tank 2 and the sediment anaerobic fermentation tank 3 are adjacent to the inside of the waste water treatment apparatus in the above embodiment, on the opposite side of the storage tank 1. An aerobic treatment tank 4 is formed. And while providing the advection part 28 in which a supernatant liquid overflows in the partition wall W24 between the said solid-liquid separation tank 2 and the aerobic processing tank 4, the said advection part 28 is said solid-liquid separation. It functions as a drainage section 24 that drains the liquid phase separated into solid and liquid in the tank 2 to the outside.) A drainage section 41 that further purifies and discharges the supernatant transferred to the aerobic treatment tank 4 is provided. Configured.

  Moreover, in the structure of FIG. 10, FIG. 11, the liquid phase anaerobic fermenter 5 is comprised as a container separate from the waste water treatment apparatus main body A, and an internal structure is comprised similarly to previous embodiment. Thus, the liquid phase can be similarly anaerobically fermented to produce biogas.

The aerobic treatment tank 4 contains a large number of sponge-like carriers 42. Also, an aeration tube 43 that diffuses air by supplying air from the air pump P5 is provided, and aerobic treatment is performed on the carrier 42 by aerobic treatment of the liquid in the aerobic treatment tank 4 by supplying air from the aeration tube 43. While the bacterium is grown, the carrier 42 is configured to be able to form a circulating flow forming a fluidized bed in the tank.
In addition, a separation wall 44 is provided in the vicinity of the drainage portion 41 to suppress mixing of solid components into the discharged wastewater to be discharged, and a clean supernatant liquid that does not contain solid components is discharged. At the same time, a return pipe 45 for returning the precipitated sludge precipitated in the lower part of the aerobic treatment tank 4 to the storage tank 1 is provided. Thus, in the aerobic treatment tank 4, the waste water from the solid-liquid separation tank 2 is further aerobically treated and purified, and the precipitated sludge generated in the aerobic treatment tank 4 is transferred to the upstream storage tank 1. It returns, and it is comprised so that processing in the sediment anaerobic fermenter 3 is possible again. The return pipe 45 has a configuration in which the water level in the pipe is raised to the horizontal pipe connection height by the pumping gas supplied to the vertical pipe 45a, and the treated water that has reached the horizontal pipe connection height is returned to the upstream side. Yes, an anaerobic gas is used as a pumping gas for the purpose of preventing the upstream storage tank 1, the solid-liquid separation tank 2, and the sediment anaerobic fermentation tank 3 from being aerobic. Anaerobic gas branches from the biogas tank T to the diffuser pipes 13, 23, and 33 for supplying biogas as anaerobic gas, and is supplied to the lower part of the vertical pipe portion of the return pipe 45 from the gas lifter pump P2. It is possible to configure (see FIG. 11).

  With such a configuration, it is possible to further purify the waste crushing waste liquid of about BOD 1300 mg / L and SS 1343 mg / L and discharge it to the outside as clean waste water of less than BOD 300 mg / L and SS 300 mg / L or less.

  In the configuration of the previous embodiment, the waste grinding waste liquid received from the receiving unit 11 is solubilized in the storage tank 1 and transferred to the solid-liquid separation tank 2. The wastewater treatment apparatus can be appropriately changed according to the properties, load, etc. of the waste pulverization treatment waste liquid. For example, in a wastewater treatment apparatus that is expected to receive a large amount of wastewater with high BOD, the storage tank 1 is enlarged. It is desirable to set and achieve sufficient solubilization.

  In addition, in the said embodiment, although the liquid phase anaerobic fermentation part was formed in the liquid phase anaerobic fermentation tank 5 as a water treatment tank different from the said solid-liquid separation tank 2, inside the said solid-liquid separation tank 2 It may be provided.

  That is, as shown in FIG. 12, the solid-liquid separation tank 2 is provided with a carrier 55a for growing anaerobic microorganisms in the precipitation separation space 22 where the liquid phase stays inside the solid-liquid separation tank 2. It is configured. The liquid phase is biogasified by anaerobic microorganisms that adhere to and grow on the carrier 55a, and is then discharged from the drainage unit 24 to the outside of the wastewater treatment apparatus main body A as clean wastewater. .

  In the above example, the liquid phase treated in the liquid-phase anaerobic fermentation tank 5 was transferred to the solid-liquid separation tank 2, but a sufficient residence time for anaerobic treatment of the liquid phase can be secured. If the liquid phase is purified to a possible property, the liquid phase is transferred directly to the outside or transferred to the aerobic treatment tank without transferring the liquid phase from the liquid phase anaerobic fermentation tank 5 to the solid-liquid separation tank 2. You can also.

  Further, in the above-described embodiment, various well-known components can be appropriately employed as the respective components such as the carrier 55a used for the gas lifter pump P2 and the anaerobic filter bed 55 and the carrier 42 used in the treatment tank described later.

  The waste water treatment apparatus of the present invention can be used as a household septic tank or the like that can efficiently decompose garbage.

A: Waste water treatment device body 1: Storage tank 11: Receiving part 12: Storage space 13: Aeration pipe 14: Advection part 2: Solid-liquid separation tank 21: Guide wall part 22: Precipitation separation space 23: Aeration pipe 24: Drainage part 25: Separation wall part 26: Advection part 26a: Slit-shaped outlet (throttle part)
26b: Inclined wall part 26c: Sedimentation layer 28: Advection part 3: Sediment anaerobic fermentation tank 31: Anaerobic fermentation space 32: Biogas extraction path 33: Aeration device 4: Aerobic treatment tank 41: Drainage part 42: Carrier 43 : Aeration pipe 44: Separation wall 45a: Vertical pipe 45: Return pipe 5: Liquid phase anaerobic fermentation tank 51: Water treatment space 52: Advection pipe 53: Transfer pipe 53a: Vertical pipe 54: Separation wall part 55: Anaerobic filter bed 55a: Carrier 56: Pumping space P1: Stirring pump P2: Gas lifter pump P3: Aeration pump P4: Stirring pump P5: Air pump T: Biogas tank W12
~ W25: Partition wall

Claims (8)

Provided with a receiving portion for receiving the waste pulverization waste liquid, and a solid-liquid separation tank for separating and separating the waste pulverization waste liquid,
While providing a liquid phase anaerobic fermentation section for biogasification of organic matter contained in the liquid phase solid-liquid separated in the solid-liquid separation tank,
A precipitate anaerobic fermenter that accepts the precipitate separated in the solid-liquid separation tank and converts it to biogas,
A convection section for advancing the precipitate from the solid-liquid separation tank to the precipitate anaerobic fermentation tank;
It is possible to prevent the reverse flow of the solid component from the precipitate anaerobic fermentation tank to the solid-liquid separation tank by closing the space between the solid-liquid separation tank and the precipitate anaerobic fermentation tank at the transfer section. While providing a throttle part to
The precipitate is transferred to the precipitate anaerobic fermentation tank through the constriction section, and the excess liquid phase of the precipitate anaerobic fermentation tank can be returned to the solid-liquid separation tank through the constriction section. An advection mechanism is provided in the precipitate anaerobic fermenter,
A wastewater treatment apparatus in which the liquid phase anaerobic fermentation section and the precipitate anaerobic fermentation tank are provided with a biogas extraction path for taking out the generated biogas to the outside.   The waste water treatment apparatus according to claim 1, wherein the liquid phase anaerobic fermentation unit is configured by providing a carrier for growing anaerobic microorganisms in a region where the liquid phase stays in the solid-liquid separation tank.   The liquid phase anaerobic fermentation section includes a water treatment tank that receives the liquid phase transferred from inside the solid-liquid separation tank, and is provided with a carrier for growing anaerobic microorganisms in the water treatment tank. The wastewater treatment apparatus according to claim 1.   The constriction section includes a slit-like outlet provided in the lower part of the solid-liquid separation tank, and the deposit in the solid-liquid separation tank is configured to be capable of forming a deposition layer that closes and deposits the slit-like outlet. The waste water treatment apparatus according to any one of claims 1 to 3.   A gas-liquid mixed phase rising from below the slit-like outlet is provided in the precipitate anaerobic fermenter is provided with an aeration device for aspirating anaerobic gas, a gas supply device is provided for intermittently supplying the anaerobic gas to the aeration device. The wastewater treatment apparatus according to claim 4, wherein a flow is formed so as to form the precipitate advection mechanism.   A solubilization tank for solubilizing the waste pulverization treatment waste liquid received by the receiving unit is provided, and a convection section is provided for advancing the waste pulverization treatment waste liquid solubilized from the solubilization tank to the solid-liquid separation tank. The waste water treatment apparatus as described in any one of 1-5.   The wastewater treatment apparatus according to any one of claims 1 to 6, further comprising an aerobic treatment tank that receives advection of a liquid phase separated in a solid-liquid separation tank and performs an aerobic treatment. An operation method of the waste water treatment apparatus according to claim 5,
A method of operating a wastewater treatment apparatus that performs gas supply by the gas supply apparatus in accordance with a decrease amount that decreases with the biogasification of the precipitate in the precipitate anaerobic fermentation tank.

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