JP6264296B2 - Organic wastewater treatment apparatus and treatment method - Google Patents

Description

  The present invention relates to an organic wastewater treatment apparatus and treatment method.

  This application claims priority on September 11, 2013 based on 201310133803.5 for which it applied to China, and uses the content here.

  In the prior art, the wastewater to be treated is supplied to the NF membrane module and separated into permeate and non-permeate water, the permeate is supplied to the RO membrane module, and separated into permeate and non-permeate water, A wastewater treatment method is known in which the non-permeate water is supplied to an evaporative concentration apparatus and concentrated.

Japanese Unexamined Patent Publication No. 2007-000789

  However, in the above treatment method, if there is an organic substance in the wastewater, the organic substance cannot be removed effectively, the pure water recovery rate of the NF membrane module and the RO membrane module is lowered, and the processing amount of the evaporation concentrator increases.

  The present invention has been made in view of the above problems, and its object is to effectively remove organic substances, reduce the processing amount of the evaporating and concentrating device, and greatly increase the pure water recovery rate of the entire system. An object of the present invention is to provide an organic wastewater treatment apparatus and treatment method that can be improved.

  Embodiment 1 of the present invention includes an aerobic tank for aerobically treating organic wastewater under aerobic conditions, a microfiltration or ultrafiltration membrane separation apparatus for solid-liquid separation of treated water in the aerobic tank, A reverse osmosis membrane or nanomembrane separation device for desalting the filtrate of the microfiltration or ultrafiltration membrane separation device, and an evaporation concentration device for further concentrating the concentrated water of the reverse osmosis membrane or nanomembrane separation device. Organic wastewater treatment equipment.

  Embodiment 2 of the present invention is an organic material according to Embodiment 1, further comprising an ion exchange device for ion exchange of the filtrate before the reverse osmosis membrane or nanomembrane separation device desalinates the filtrate. Wastewater treatment equipment.

  Embodiment 3 of the present invention is the organic wastewater treatment apparatus according to Embodiment 2, further comprising an alkali addition device that adds alkali to the concentrated water before the evaporative concentration device further concentrates the concentrated water. is there.

  Embodiment 4 of the present invention is the organic wastewater treatment apparatus according to Embodiment 2, further comprising a condensed water transport member that transports condensed water obtained by condensing the water evaporated from the evaporative concentration apparatus to the aerobic tank. .

  In Embodiment 5 of the present invention, before the evaporative concentration apparatus further concentrates the concentrated water, an alkali addition apparatus that adds alkali to the concentrated water, and condensed water obtained by condensing water evaporated from the evaporative concentration apparatus are provided. It is the processing apparatus of the organic waste_water | drain of Embodiment 2 further provided with the condensed water conveyance member conveyed to the said aerobic tank.

  Embodiment 6 of the present invention is the organic wastewater treatment apparatus according to Embodiment 1, further comprising an alkali addition device that adds alkali to the concentrated water before the evaporative concentration device further concentrates the concentrated water. is there.

  Embodiment 7 of the present invention is the organic wastewater treatment apparatus according to Embodiment 6, further comprising a condensed water transport member that transports condensed water obtained by condensing the water evaporated from the evaporative concentration apparatus to the aerobic tank. .

  Embodiment 8 of the present invention is the organic wastewater treatment apparatus according to Embodiment 1, further comprising a condensed water transport member that transports condensed water obtained by condensing the water evaporated from the evaporative concentration apparatus to the aerobic tank. is there.

  In Embodiment 9 of the present invention, an aerobic treatment step in which an organic wastewater is aerobically treated under an aerobic condition in an aerobic tank, and treated water in the aerobic tank is solidified by a microfiltration or ultrafiltration membrane separator. A solid-liquid separation step for liquid separation, a desalting treatment step for desalting the filtrate of the microfiltration or ultrafiltration membrane separation device by a reverse osmosis membrane or a nano membrane separation device, and the reverse osmosis membrane by an evaporation concentration device Or the evaporative concentration process which further concentrates the concentrate of a nano membrane separation apparatus, The processing method of the organic waste_water | drain.

  Embodiment 10 of this invention is the processing method of the organic waste_water | drain of Embodiment 9 further equipped with the ion exchange process of ion-exchanging the said filtrate with an ion exchange apparatus before the said desalting process process.

  The eleventh embodiment of the present invention is the organic wastewater treatment method according to the tenth embodiment, further comprising an alkali addition step of adding alkali to the concentrated water by an alkali addition device before the evaporation and concentration step.

  Embodiment 12 of the present invention is the organic waste water according to embodiment 10, further comprising a condensed water conveyance step of conveying condensed water obtained by condensing moisture evaporated from the evaporating and concentrating device by the condensed water conveyance member to the aerobic tank. It is a processing method.

  In the thirteenth embodiment of the present invention, before the evaporative concentration step, an alkali addition step of adding alkali to the concentrated water by an alkali addition device, and condensation condensed water evaporated from the evaporation concentration device by a condensed water transport member It is the processing method of the organic waste_water | drain of Embodiment 10 further provided with the condensed water conveyance process which conveys water to the said aerobic tank.

  Embodiment 14 of the present invention is the organic wastewater treatment method according to Embodiment 9, further comprising an alkali addition step of adding alkali to the concentrated water by an alkali addition device before the evaporation and concentration step.

  Embodiment 15 of the present invention is an organic wastewater according to embodiment 14, further comprising a condensed water transporting step of transporting condensed water obtained by condensing water evaporated from the evaporating and concentrating device by a condensed water transporting member to the aerobic tank. It is a processing method.

  Embodiment 16 of the present invention is an organic wastewater according to embodiment 9, further comprising a condensed water conveyance step of conveying condensed water obtained by condensing moisture evaporated from the evaporating and concentrating device by a condensed water conveying member to the aerobic tank. It is a processing method.

  Embodiment 17 of the present invention further comprises a chemical washing step for washing the filtration membrane of the membrane separation unit of the microfiltration or ultrafiltration membrane separation device in a state where the solid-liquid separation step is stopped, the chemical washing step A chemical solution injection step of injecting a chemical solution into the membrane separation unit of the microfiltration or ultrafiltration membrane separation device to wash the filtration membrane, and a state in which the chemical solution is injected into the membrane separation unit, The stationary filtration step where the aeration pipe stops the aeration of the outer filtration membrane separation device, the air diffusion step of performing the aeration on the microfiltration or ultrafiltration membrane separation device, and the microfiltration of water Or a water washing step of injecting into the membrane separation unit of the ultrafiltration membrane separator and washing the filtration membrane with water, and the microfiltration or ultrafiltration membrane separator from the membrane separation unit through the aeration pipe with water after washing Discharged into the membrane separation tank Degree and a method of treating organic waste water according to technical solution 9 comprising a.

  Embodiment 18 of the present invention is the organic wastewater treatment method according to Embodiment 17, wherein the chemical solution is a hypochlorite chemical solution.

  Embodiment 19 of the present invention is the organic wastewater treatment method according to embodiment 18, wherein the chemical washing step is performed once again, and in the second chemical washing step, the chemical solution is an acidic chemical solution.

According to the above embodiment of the present invention, organic substances can be effectively removed, the processing amount of the evaporative concentration apparatus is reduced, and the pure water recovery rate of the entire system is greatly improved.
By the ion exchange device and the process, divalent ion components in the filtrate can be removed, and scaling can be prevented from occurring in the reverse osmosis membrane or nano membrane separation device and the evaporation concentration device.
The alkali concentrator and the process can prevent the evaporative concentrator from being corroded by chlorine.
By the condensed water transport member and the process, the heat generated from the evaporative concentration device is supplied to the aerobic tank, the activated sludge in the aerobic tank is activated, and the processing efficiency and the filtration efficiency are improved.
Reverse osmosis membrane or nano membrane separation device avoids high concentrations of hypochlorite, acid, active surfactant, etc. from being mixed in the filtrate filtered by the filtration membrane separation device by the water washing process and discharge process Can be adversely affected.
In particular, in the coke industry, with the promotion of the introduction of coke dry fire extinguishing equipment (Coke Dry Quenching / CDQ), technology for improving the quality of wastewater treatment water and reducing the amount of wastewater is required.
The coke wastewater contains a lot of refractory organic substances such as humin and toxic substances such as cyan and phenol, so that the biological treatment tank becomes unstable, which is one of the reasons why the RO recovery rate cannot be improved.

  In the present invention, since the biological reaction tank is heated by the high-temperature condensed water generated from the evaporation concentrator, stable biological treatment is possible, and the RO / NF recovery rate can be improved and the subsequent evaporator concentrator can be downsized. .

FIG. 1 is a schematic diagram of an organic wastewater treatment apparatus of the present invention. FIG. 2 is a schematic view of the aerobic tank and the microfiltration or ultrafiltration membrane separation apparatus portion of the present invention, illustrating the hypochlorite chemical solution injection step. FIG. 3 is a schematic diagram of the aerobic tank and the microfiltration or ultrafiltration membrane separation device portion of the present invention, illustrating the stationary process. FIG. 4 is a schematic view of the aerobic tank and the microfiltration or ultrafiltration membrane separation apparatus part of the present invention, illustrating the air diffusion step. FIG. 5 is a schematic view of the aerobic tank and the microfiltration or ultrafiltration membrane separation device of the present invention, illustrating the water washing step. FIG. 6 is a schematic diagram of the aerobic tank and the microfiltration or ultrafiltration membrane separation apparatus portion of the present invention, illustrating the discharge process. FIG. 7 is a schematic diagram of the aerobic tank and the microfiltration or ultrafiltration membrane separation device portion of the present invention, illustrating an acidic chemical solution injection step.

Specific embodiments of the present invention will be described in detail with reference to FIGS.
As shown in FIG. 1, the organic wastewater treatment apparatus mainly includes an aerobic tank 4, a microfiltration or ultrafiltration membrane separation device 5, a water softener 6 serving as an ion exchange device, and a reverse osmosis membrane or A nanomembrane separation device 7, an alkali addition device 8, and an evaporation concentration device 9 are provided.

  Raw water used as organic wastewater is first introduced into the aerobic tank 4. In the aerobic tank 4, the raw water is subjected to aerobic treatment under aerobic conditions. That is, the aeration tube 41 is provided in the aerobic tank 4, and after introducing air into the aeration tube 41 by the floor B1, the air is diffused in the aeration tube 41, and the aerobic microorganisms in the aerobic tank 4 Decompose organic matter.

  The microfiltration or ultrafiltration membrane separation device 5 performs solid-liquid separation on the treated water treated in the aerobic tank 4. The microfiltration or ultrafiltration membrane separation device 5 includes a membrane separation tank 51, a diffuser tube 52, and a membrane separation unit 53. The membrane separation unit 53 is provided in the membrane separation tank 51 using a microfiltration membrane (MF membrane) or an ultrafiltration membrane (UF membrane). The air diffuser 52 is provided below the membrane separation unit 53.

  Treated water treated in the aerobic tank 4 is introduced into the membrane separation tank 51. The treated water is separated into solid and liquid by the membrane separation unit 53. Also, air is introduced into the diffuser pipe 52 by the floor B1, diffused in the membrane separation tank 51, and the filtration membrane of the membrane separation unit 53 is vibrated by the flow of the aeration, thereby preventing clogging of the pores of the filtration membrane. The microfiltration membrane (MF membrane) or ultrafiltration membrane (UF membrane) of the membrane separation unit 53 may be any of a flat membrane, a tubular membrane, a hollow fiber membrane, and the like.

  The filtrate after solid-liquid separation passes through the water softener 6, and the filtrate is ion-exchanged with the water softener 6 to remove divalent ion components such as Ca ions and Mg ions in the filtrate, and reverse osmosis membrane or nano membrane separation. Scaling is prevented from occurring in the apparatus and the evaporative concentration apparatus.

  The reverse osmosis membrane or nanomembrane separation device 7 desalinates the filtrate, filtrate water tank 71, first-stage reverse osmosis membrane or nanomembrane separation module 72, and second-stage reverse osmosis membrane or nanomembrane. A separation module 73 is provided.

The reverse osmosis membrane or nanomembrane separation device 7 may be one-stage processing or two-stage processing. The reverse osmosis membrane or the reverse osmosis membrane (RO membrane) or nanomembrane (NF membrane) of the nanomembrane separation device 7 may be any one of a flat membrane, a tubular membrane, a hollow fiber membrane, a spiral membrane and the like.
After the ion-exchanged filtrate is introduced into the filtrate water tank 71, it is supplied to the first-stage reverse osmosis membrane or nanomembrane separation module 72 and filtered through the first-stage reverse osmosis membrane or nanomembrane separation module 72. The first-stage treated water is introduced into the second-stage reverse osmosis membrane or nanomembrane separation module 73, and the first-stage concentrated water discharged from the first-stage reverse osmosis membrane or nanomembrane separation module 72 is A part is introduced into the concentrated raw water tank 10, and the other part is mixed into the filtrate and introduced again into the first-stage reverse osmosis membrane or nanomembrane separation module 72. The second-stage treated water filtered by the second-stage reverse osmosis membrane or nano-membrane separation module 73 is recovered and used, and the second-stage concentration from the second-stage reverse osmosis membrane or nano-membrane separation module 73 is recovered. A part of the water is returned to the filtrate water tank 71, and the other part is mixed into the first-stage treated water and introduced again into the second-stage reverse osmosis membrane or nano-membrane separation module 73.

Before the first stage concentrated water is introduced into the concentrated raw water tank 10, an alkali such as NaOH is added to the first stage concentrated water by the alkali addition device 8 to prevent the evaporation concentration device 9 from being corroded by chlorine. it can.
The first stage concentrated water in the concentrated raw water tank 10 is introduced into the evaporative concentration apparatus 9. In the evaporative concentrator 9, the first stage concentrated water is heated, evaporated under reduced pressure, and further concentrated. Further, the concentrated water is introduced into the concentrated water tank 11 and discarded as industrial waste.
Condensed water obtained by condensing water evaporated by the evaporating and concentrating device 9 is conveyed to the aerobic tank 4 by the conveying pipe 12 serving as a condensed water conveying member. Therefore, the heat generated from the evaporating and concentrating device 9 is also supplied to the aerobic tank 4 and the activated sludge in the aerobic tank 4 is activated to improve the processing efficiency and the filtration efficiency.

And the chemical washing process which wash | cleans the filtration membrane of the microfiltration or ultrafiltration membrane separation apparatus of this invention with reference to FIGS.
The chemical washing step is to wash the filtration membrane of the membrane separation unit 53 in a state where the solid-liquid separation with respect to the treated water of the microfiltration or ultrafiltration membrane separation device 5 is stopped. A process, a stationary process, an air diffusion process, a water washing process, a discharge process, an acidic chemical solution injection process, a stationary process, an air diffusion process, a water washing process, and a discharge process are performed.

In the hypochlorite chemical injection step, the hypochlorite chemical is injected into the membrane separation unit 53 of the microfiltration or ultrafiltration membrane separation device 5 to wash the filtration membrane.
That is, as shown in FIG. 2, the pump P1 is operated, the filtrate filtered by the membrane separation unit 53 and stored in the water storage tank 12 is introduced into the membrane separation unit 53, and the pump P2 is operated to perform hypochlorite. The hypochlorite chemical stored in the chemical tank 13 is introduced into the membrane separation unit 53, and the filtrate and the hypochlorite chemical are mixed together at location A and introduced together into the membrane separation unit 53. 53 filtration membranes are washed. The hypochlorite chemical may be made by adding NaClO, Ca (ClO) ₂ , ClKO or the like to industrial water.
At the same time, the operation of the pump P3 is stopped, and the introduction of the acidic chemical solution stored in the acidic chemical solution tank 14 to the membrane separation unit 53 is stopped.
At the same time, the operation of the floor B1 is stopped, and the introduction of the air into the diffuser pipe 41 in the treatment tank 4 and the diffuser pipe 54 and the diffuser pipe 52 in the membrane separation tank 51 is stopped. Therefore, the air diffuser of the air diffuser 41, the air diffuser 54, and the air diffuser 52 is stopped.
At the same time, the operation of the pump P4 is stopped, and the derivation of the filtrate from the membrane separation unit 53 is stopped.

In the standing step, the microfiltration or ultrafiltration membrane separation device 5 enters a state where the aeration operation is stopped in a state where the hypochlorite chemical solution is injected into the membrane separation unit 53.
That is, as shown in FIG. 3, the operations of the pump P1, the pump P2, and the pump P3 are stopped, and the introduction of the filtrate, hypochlorite chemical, and acidic chemical into the membrane separation unit 53 is stopped. At the same time, the operation of the floor B1 is stopped, and the introduction of the air into the diffuser pipe 41 of the treatment tank 4 and the diffuser pipe 54 and the diffuser pipe 52 in the membrane separation tank 51 is stopped. Therefore, the air diffuser of the air diffuser 41, the air diffuser 54, and the air diffuser 52 is stopped. At the same time, the operation of the pump P4 is stopped, and the derivation of the filtrate from the membrane separation unit 53 is stopped.

In the air diffusion step, air is diffused into the microfiltration or ultrafiltration membrane separation device 5.
That is, as shown in FIG. 4, the floor B <b> 1 is operated, and air is introduced into the diffuser pipe 41 in the treatment tank 4 and the diffuser pipe 54 and the diffuser pipe 52 in the membrane separation tank 51. Therefore, the diffuser 41, the diffuser 54, and the diffuser 52 are diffused.
At the same time, the operations of the pump P1, the pump P2, and the pump P3 are stopped, and the introduction of the filtrate, hypochlorite chemical solution, and acidic chemical solution into the membrane separation unit 53 is stopped. At the same time, the operation of the pump P4 is stopped, and the derivation of the filtrate from the membrane separation unit 53 is stopped.

In the water washing step, water is injected into the membrane separation unit 53 of the microfiltration or ultrafiltration membrane separation device 5 to wash the filtration membrane.
That is, as shown in FIG. 5, the pump P1 is operated, the filtrate filtered by the membrane separation unit 53 and stored in the water storage tank 12 is introduced into the membrane separation unit 53, and the filtration membrane is washed with water. The floor B1 is operated, and air is introduced into the diffuser pipe 41 in the treatment tank 4 and the diffuser pipe 54 and the diffuser pipe 52 in the membrane separation tank 51, respectively. Therefore, the diffuser 41, the diffuser 54, and the diffuser 52 are diffused.
At the same time, the operation of the pump P2 and the pump P3 is stopped, and the introduction of the hypochlorite chemical solution and the acidic chemical solution into the membrane separation unit 53 is stopped.
At the same time, the operation of the pump P4 is stopped, and the derivation of the filtrate from the membrane separation unit 53 is stopped.

In the discharging step, the water after washing returns to the aeration pipe 52 and is discharged to the membrane separation tank 51 of the microfiltration or ultrafiltration membrane separation device 5.
That is, as shown in FIG. 6, the pump P <b> 4 is operated and the water after washing is led out from the membrane separation unit 53. The floor B1 is operated, and air is introduced into the diffuser pipe 41 in the treatment tank 4 and the diffuser pipe 54 and the diffuser pipe 52 in the membrane separation tank 51, respectively. Therefore, the diffuser 41, the diffuser 54, and the diffuser 52 are diffused. Moreover, the water and air after the water washing are mixed at the point C, and both are introduced into the diffuser tube 52, and thus the water after the water washing enters the membrane separation tank 51.
At the same time, the operations of the pump P1, the pump P2, and the pump P3 are stopped, and the introduction of the filtrate, hypochlorite chemical solution, and acidic chemical solution into the membrane separation unit 53 is stopped.

In the acidic chemical solution injection step, the acidic chemical solution is injected into the membrane separation unit 53 of the microfiltration or ultrafiltration membrane separation device 5 to wash the filtration membrane.
As shown in FIG. 7, the pump P1 is operated, the filtrate filtered by the membrane separation unit 53 and stored in the water storage tank 12 is introduced into the membrane separation unit 53, and the pump P3 is operated and stored in the acidic chemical liquid tank 14. The acidic chemical solution is introduced into the membrane separation unit 53, the filtrate and the acidic chemical solution are mixed at the B location, and introduced together into the membrane separation unit 53, and the filtration membrane of the membrane separation unit 53 is washed. The acidic chemical solution may be made by adding H ₂ SO ₄ or the like to industrial water.
At the same time, the operation of the pump P2 is stopped and the introduction of the hypochlorite chemical stored in the hypochlorite chemical tank 13 to the membrane separation unit 53 is stopped.
At the same time, the operation of the floor B1 is stopped, and the introduction of the air into the diffuser pipe 41 in the treatment tank 4 and the diffuser pipe 54 and the diffuser pipe 52 in the membrane separation tank 51 is stopped. Therefore, the air diffuser of the air diffuser 41, the air diffuser 54, and the air diffuser 52 is stopped.
At the same time, the operation of the pump P4 is stopped, and the derivation of the filtrate from the membrane separation unit 53 is stopped.
Thereafter, the stationary step, the air diffusion step, the water washing step, and the discharging step are performed once more.

By the chemical washing step, organic substances on the surface of the filtration membrane can be removed, and it is avoided that hypochlorite, acid, etc. are mixed in the filtrate filtered by the filtration membrane separator at a high concentration. It is possible to prevent adverse effects on the osmosis membrane or the nanomembrane separation device.
It is preferable that the organic wastewater treatment apparatus further includes an oil / water separation tank, a flow rate adjustment tank, and a pressurized flotation device.

The raw water is first introduced into the oil / water separation tank. Oil is separated from raw water in an oil-water separation tank.
And the raw | natural water which isolate | separated oil is introduce | transduced into a flow control tank. A flow rate adjustment tank controls the flow rate introduced into the pressurized levitation device of the raw water.
The pressurized levitation device levitates and removes suspended matter containing SiO ₂ and Ca in the raw water. The pressure levitation device includes a reaction tank, a pressure levitation tank, and a neutralization tank.

First, raw water is introduced into a reaction tank, and polyaluminum chloride (PAC) and polyacrylamide (PAM) as flocculants are placed in order in the two reaction tanks, and stirred with a stirrer to obtain polyaluminum chloride (PAC), Polyacrylamide (PAM) is sufficiently solubilized in the raw water, and suspended substances aggregate.
Then, in the pressurized levitation tank, air is injected into the raw water by an air injection device, and a large amount of fine bubbles are generated. Lift using buoyancy. After the suspended matter floats up to the surface of the raw water, the suspended matter is removed from the surface by a scraping device.

In addition, SiO ₂ has a gel shape and a negative charge. When polyaluminum chloride (PAC) is added, SiO ₂ aggregates and floats and is removed from the raw water as described above.
About Ca, it elutes in raw | natural water from the concrete water tank used as a reaction tank. In order to remove Ca, Na ₂ CO ₃ is previously placed in the flow rate adjusting tank, Ca is not dissolved in the raw water, and is agglomerated by the aggregating agent, floated, and removed from the raw water as described above.
Raw water from which suspended solids have been removed is introduced into the neutralization tank. H ₂ SO ₄ is put into the neutralization tank to neutralize the raw water.
Thereafter, the raw water whose pH value is adjusted is put into the aerobic tank 4, and the aerobic treatment step, the solid-liquid separation step, the ion exchange step, the desalting treatment step, the alkali addition step, the evaporation concentration step, and the condensed water conveyance are sequentially performed Perform the process.

  The present invention is further described specifically by way of examples.

The operational status of the organic waste water processing apparatus, the original water treatment is operated at 8~10m ³ / d, a design-time ^16m 3 / d.

Regarding the operating conditions of the pressure levitation device, the amount of raw water for treatment is 1 m ³ / d, the water area load is 24 m ³ / m ² / d, and the residence time is 2.8 h. The injection rate of polyaluminum chloride (PAC) is 500 mg PAC pure fraction / L, and the polyacrylamide (PAM) injection rate is 3 mg PAM pure fraction / L. The pH value of the reaction tank is 8.5, and the pH value of the neutralization tank is 7.5.

Regarding the operating conditions of the microfiltration or ultrafiltration membrane separation device 5, the volumetric load of biochemical oxygen demand (BOD) is 0.045 kg BOD / m ³ / d. The biochemical oxygen demand (BOD) sludge load is 0.015 kg BOD / kg MLSS / d. The membrane area of the filtration membrane is 10 m ² / e × 5e = 50 m ² . The flux of the filtration membrane is 0.18 m ³ / m ² / d.

Regarding the operating conditions of the reverse osmosis membrane or nanomembrane separation device 7, the amount of raw water for treatment is 1 m ³ / h, the amount of treated water is 0.8 m ³ / h, and the recovery rate is 80% or more. . The reverse osmosis membrane or nano membrane separation module 72 in the first stage of the reverse osmosis membrane or nano membrane separation device 7 is a contamination-resistant low-pressure spiral RO membrane element (manufactured by Nitto Denko: LFC3-LD-4040). The film area is 7.43 m ² / line × 9 lines = 67 m ² , and the flux is 0.33 m ³ / m ² / d.
The reverse osmosis membrane or nanomembrane separation module 73 in the second stage of the reverse osmosis membrane or nanomembrane separation device 7 is an ultra-low pressure RO membrane element (Nitto Denko: ESPA2-4040), and the membrane area of the filtration membrane is 7. 9 m ² / line × 6 lines = 47 m ² and the flux is 0.41 m ³ / m ² / d.
Regarding the recovery rate, the first-stage reverse osmosis membrane or nanomembrane separation module 72 is 80%, and the second-stage reverse osmosis membrane or nanomembrane separation module 73 is 88%.

The operating conditions of evaporation apparatus 9, the original water treatment is 1.6~3.2m ³ / d, could be concentrated 8-16 fold, leaving the concentrated water is 0.2 m ³ / d. The evaporating and concentrating device 9 is a vacuum evaporating steam heating type (treatment water amount: 3.2 m ³ / d device structure: open frame type).

  Although the best embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. About a concrete structure, you may change suitably in the range which does not deviate from the meaning of this invention, and you may combine said embodiment arbitrarily.

For example, in the above-described embodiment, the organic wastewater treatment apparatus includes the aerobic tank 4, the microfiltration or ultrafiltration membrane separation device 5, the water softener 6 serving as an ion exchange device, the reverse osmosis membrane or the nano-scale. A membrane separation device 7, an alkali addition device 8, an evaporation concentration device 9, and a condensed water transport member are provided. However, the present invention is not limited to this, and the organic wastewater treatment device is an aerobic tank 4, a microfiltration or ultrafiltration membrane separation device 5, a reverse osmosis membrane or nanomembrane separation device 7, and evaporation concentration. If the apparatus 9 is provided, the main object of the present invention can be realized.
Moreover, the processing apparatus of organic waste_water | drain may also contain any one or more among these apparatuses, the water softener 6, the alkali addition apparatus 8, and a condensed water conveyance member.

  For example, in the above-described embodiment, the chemical washing process includes the hypochlorite chemical injection process, the stationary process, the air diffusion process, the water washing process, the discharge process, the acidic chemical liquid injection process, the static process, and the air diffusion process. A process, a washing process, and a discharge process are provided. However, the present invention is not limited to this, and the chemical washing process may include only a hypochlorite chemical liquid injection process, a stationary process, an air diffusion process, a water washing process, and a discharge process.

According to the above embodiment of the present invention, organic substances can be effectively removed, the processing amount of the evaporative concentration apparatus is reduced, and the pure water recovery rate of the entire system is greatly improved. By the ion exchange device and the process, divalent ion components in the filtrate can be removed, and scaling can be prevented from occurring in the reverse osmosis membrane or nano membrane separation device and the evaporation concentration device. The alkali concentrator and the process can prevent the evaporative concentrator from being corroded by chlorine. By the condensed water transport member and the process, the heat generated from the evaporative concentration device is supplied to the aerobic tank, the activated sludge in the aerobic tank is activated, and the processing efficiency and the filtration efficiency are improved. Reverse osmosis membrane or nano membrane separation device avoids high concentrations of hypochlorite, acid, active surfactant, etc. from being mixed in the filtrate filtered by the filtration membrane separation device by the water washing process and discharge process Can be adversely affected.
Furthermore, in the present invention, the biological reaction tank is heated by the high-temperature condensate generated from the evaporation concentrator, so that stable biological treatment is possible, and the RO / NF recovery rate can be improved and the subsequent evaporator concentrator can be downsized. It becomes.

4 Aerobic tank 5 Microfiltration or ultrafiltration membrane separation device 6 Water softener 7 Reverse osmosis membrane or nano membrane separation device 8 Alkali addition device 9 Evaporation concentration device 10 Concentrated raw water tank 11 Concentrated water tank 12 Conveying pipe

Claims (9)

An aerobic tank for aerobic treatment of organic wastewater under aerobic conditions;
A microfiltration or ultrafiltration membrane separator for solid-liquid separation of treated water in the aerobic tank;
A reverse osmosis membrane or a nano membrane separator for desalting the filtrate of the microfiltration or ultrafiltration membrane separator;
An evaporating and concentrating device for further concentrating the concentrated water of the reverse osmosis membrane or the nano membrane separation device;
An organic wastewater treatment apparatus comprising: a condensed water transport member that transports condensed water obtained by condensing water evaporated from the evaporative concentration apparatus to the aerobic tank .   The organic wastewater treatment according to claim 1, further comprising an ion exchange device for ion exchange of the filtrate before the reverse osmosis membrane or the nano membrane separation device desalinates the filtrate. apparatus. The evaporator before the concentrator further concentrating the concentrated water, the organic waste water processing system according to claim 1 or 2, further comprising an alkali addition device for adding an alkali to the concentrated water. An aerobic treatment process for aerobic treatment of organic wastewater in an aerobic condition by an aerobic tank;
A solid-liquid separation step for solid-liquid separation of the treated water in the aerobic tank by means of a microfiltration or ultrafiltration membrane separation device;
A desalting treatment step of desalting the filtrate of the microfiltration or ultrafiltration membrane separation device by a reverse osmosis membrane or a nanomembrane separation device;
An evaporation concentration step of further concentrating the concentrated solution of the reverse osmosis membrane or the nano membrane separation device by an evaporation concentration device;
And a condensed water transporting step of transporting condensed water obtained by condensing water evaporated from the evaporating and concentrating device to the aerobic tank by a condensed water transporting member . The organic wastewater treatment method according to claim 4 , further comprising an ion exchange step of ion exchange of the filtrate by an ion exchange device before the desalting treatment step. The organic wastewater treatment method according to claim 4 or 5 , further comprising an alkali addition step of adding alkali to the concentrated water by an alkali addition device before the evaporation and concentration step. An aerobic treatment process for aerobic treatment of organic wastewater in an aerobic condition by an aerobic tank;
A solid-liquid separation step for solid-liquid separation of the treated water in the aerobic tank by means of a microfiltration or ultrafiltration membrane separation device;
A desalting treatment step of desalting the filtrate of the microfiltration or ultrafiltration membrane separation device by a reverse osmosis membrane or a nanomembrane separation device;
An evaporation concentration step of further concentrating the concentrated solution of the reverse osmosis membrane or the nano membrane separation device by an evaporation concentration device;
In a state where the solid-liquid separation process is stopped, and a chemical washing step of washing the filtration membrane of the membrane separation unit of the microfiltration or ultrafiltration membrane separation device,
The chemical washing step is a chemical solution injection step of injecting a chemical solution into the membrane separation unit of the microfiltration or ultrafiltration membrane separation device to wash the filtration membrane,
In a situation where a chemical solution is injected into the membrane separation unit, a stationary step where the aeration by the aeration pipe is stopped in the microfiltration or ultrafiltration membrane separation device, and
An air diffusing step of performing the air diffusing on the microfiltration or ultrafiltration membrane separation device;
A water washing step of rinsing the filtration membrane by injecting water into the membrane separation unit of the microfiltration or ultrafiltration membrane separation device;
Process water after washing with water from the membrane separation unit of the organic waste water, characterized in Rukoto to have a, a discharge step of discharging the membrane separation tank of the microfiltration or ultrafiltration membrane separation device through the air diffuser pipe Method. The said chemical | medical solution is a hypochlorite chemical | medical solution, The processing method of the organic waste_water | drain of Claim 7 characterized by the above-mentioned. The method for treating organic waste water according to claim 7 or 8 , wherein the chemical washing step is performed once again, and in the second chemical washing step, the chemical solution is an acidic chemical solution.

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