JPH02268892A - Sewage treating device using hollow-fiber-membrane module - Google Patents

Abstract

PURPOSE:To eliminate the disorder and entanglement of hollow-fiber membrane, to prolong the service life, to easily exchange the membrane and to standardize the capacity, scale, etc., by intermittently sucking the inside of the hollow-fiber- membrane module packed in a solid-liq. separation tank. CONSTITUTION:A hollow-fiber-membrane module 13 is packed in a solid-liq. separation tank 12, and an activated sludge-mixed liq. 8 is introduced into the tank 12 from a bioreactor 3. The inside of the hollow-fiber membrane 13b in a suction chamber 13 is intermittently sucked by a suction device 15, and the liq. mixture 8 is separated into solid and liq. The operating time of the suction device 15 is appropriately set by an intermittent timer 16, and the sucking time and downtime are changed. As a result, the handling is facilitated, and the capacity can be standardized. Furthermore, the entanglement of the membranes is eliminated, and the service life is prolonged.

Description

Detailed Description of the Invention [Industrial Application Field 1] The present invention uses a hollow fiber membrane module for wastewater treatment filled with a bundle of hollow fiber membranes for solid-liquid separation in combination with a bioreactor (biological reaction treatment W). This relates to sewage treatment equipment.

[Conventional technology] Conventionally, solid-liquid separation membranes for this type of wastewater treatment are:
Those using flat membranes or tubular membranes are known.

However, in the conventional solid-liquid separation described above, it is necessary to provide a turbulent flow to the mixed liquid in order to prevent the occurrence of concentration polarization and the adhesion of a del layer of sludge on the membrane surface, which increases the power required. There was a problem.

In addition, ball cleaning was required to remove del debris adhering to the membrane surface, making it difficult to control the permeation flow rate.

In order to solve the above-mentioned conventional problems, the present inventors filled a hollow fiber membrane into an activated sludge mixture that had been subjected to biological reaction treatment, and intermittently sucked the inside of the hollow fiber membrane to remove the sewage. We have developed a wastewater treatment method and device that separates wastewater into a permeated liquid and a concentrated liquid, and also changes the suction/pause time of the intermittent suction described above so that the permeation flow rate is t(Jl).

However, the hollow fiber membranes not only become entangled in the solid-liquid separation tank or bioreactor due to turbulent flow, reducing treatment efficiency, but also have problems such as the short lifespan of the hollow fiber membranes and the difficulty of replacing them. Ah 1.

L Problems to be Solved by the Invention] The present invention has been made to solve the above-mentioned conventional problems, and its purpose is to eliminate disturbance and entanglement of hollow fiber membranes and extend their lifespan. The object of the present invention is to provide a sewage treatment device using a hollow fiber membrane module for sewage treatment, which can not only be modified, but also easily replaced, and can standardize processing capacity, scale, etc.

[Means for Solving the Problems 1] A sewage treatment VC system using the hollow fiber membrane module for sewage treatment of the present invention includes a bioreactor that performs biological reaction treatment on organic sewage, and an activated sludge mixture from the bioreactor. Setting the solid-liquid separation tank to be introduced, the hollow fiber membrane module filled in the solid-liquid separation tank, a means for intermittently suctioning the inside of the hollow fiber membrane, and a suction vf of the intermittent suction means. This system is characterized by comprising a timer for returning the concentrated liquid in the solid-liquid separation tank to the bioreactor.

Another apparatus of the present invention includes a bioreactor for biological reaction treatment of organic wastewater, a hollow fiber membrane module housed in the bioreactor, and a means for intermittently sucking the inside of the hollow fiber membrane. , and a tie 7 for setting the suction time of the intermittent suction means.

The above-mentioned hollow fiber membrane module is characterized by being constructed by housing a bundle of multiple hollow fiber membranes that separate solid-liquid from an activated sludge mixture subjected to biological reaction treatment into a honeycomb tube so that they can freely move. be.

[Embodiment 1] An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 is a sand removal device, and 2 is a screen, which removes solid matter such as earth and sand mixed into the raw solution.

3 is a variable capacity bioreactor (biological reaction treatment tank), into which the above-mentioned stock solution flows in through an inflow pipe 4. In this embodiment, it is designed to flow down naturally, but a pump ( (not shown). If the raw solution is wastewater containing oil, such as kitchen wastewater, it should be introduced into the bioreactor after oil separation.

The inflow amount of the stock solution changes over time, and therefore the water level of the mixed liquid containing biological flocs in the bioreactor 3, that is, the activated sludge mixed liquid 5, fluctuates up and down (HWL, LWL). There is.

An aeration pipe 6 is disposed at the bottom of the bioreactor 3 to diffuse air sent from an aeration blower 7 into the liquid mixture 5.

Reference numeral 8 denotes an outflow pipe for discharging the mixed liquid from the bottom of the bioreactor 3 using a pump 9.

The mixed liquid discharged from the outflow pipe 8 is sent to a solid-liquid separation tank 12 after solids are removed by a screen 10, a sand removal device 11, etc. on the way.

The solid-liquid separation tank 12 is filled with hollow fiber membrane modules 13, as shown in FIG.

As shown in FIGS. 3 and 4, the hollow fiber membrane module 13 is constructed by accommodating a bundle of a large number of hollow fiber membranes 13b in a honeycomb tube 13a.

The hollow fiber membrane 13b is, for example, a filament-like hollow tube made of synthetic 1 (oil) such as polyethylene and having a diameter of about 0.8 m16 and having minute holes of about 0.1 micron.

The hollow fiber m13 is not limited to this, but any hollow fiber membrane that has been used or developed so far may be used.

The upper end of the bundle of hollow fibers [13b] is fixed in a state where it opens into the suction chamber 13c. On the other hand, the lower end portion of the hollow fiber membrane 13b is closed. Note that the hollow fiber membrane 13b may be suspended in a loop shape, and both ends of the hollow fiber membrane 13b may be fixed in the suction chamber 13c. Further, the hollow fiber membrane module 13 may be oriented in any direction, such as horizontally or obliquely.

In FIG. 1, 14 is a return pipe, and the solid-liquid separation tank 1
The concentrated liquid in bioreactor 2 is returned to bioreactor 3.

Reference numeral 15 denotes a suction device, which sucks the inside of the suction chamber 13c, that is, the hollow fiber membrane 13b to create a low pressure state, thereby sucking only the liquid portion of the mixed liquid excluding solids, microorganisms, viruses, etc. Water is allowed to permeate inside the thread membrane 13b to separate solid and liquid.

I6 is an intermittent timer, and the above-mentioned suction! By appropriately setting the operating time of the device 15, the suction time and rest time can be changed.

Next, the operation of the apparatus of the above embodiment will be explained.

First, solids such as sand are separated from the raw organic wastewater using the sand removal device 1 and the screen 2 and introduced into the bioreactor 3 through the inlet pipe 4.

The organic wastewater introduced into the bioreactor 3 becomes an activated sludge mixture 5. The water level of the activated sludge mixture 5 fluctuates up and down in the bioreactor 3 according to changes in the amount of inflow from the inflow pipe 4 and the amount of outflow from the outflow pipe 8.

An aeration pipe 6 is placed at the bottom of the bioreactor 3, and air is supplied from an aeration blower 7, so organic matter in the wastewater that has flowed into the bioreactor 3 is adsorbed by aerobic microbial flocs, and further It is oxidized and decomposed and purified.

The treated water containing activated sludge is sent from the outflow pipe 8 to the solid-liquid separation tank 12 by the pump 9.

The mixed liquid that has flowed into the solid-liquid separation tank 12 is sucked into the suction chamber 13c through the fine holes of the hollow fibers 11i13b in the honeycomb tube 13a, and the permeated liquid is drawn out as treated water through the water pipe 17. It will be done.

The concentrated liquid that is not sucked by the hollow fiber membrane 13b is returned W14.
is returned to the bioreactor 3 through the

The suction device 15 is operated intermittently by an intermittent timer 16 to control the permeation flow rate. The intermittent tie? -17 is preferably controlled by a computer.

In FIG. 5, the hollow fiber membrane module 13 is housed in the bioreactor 3 to make the entire device compact.

Although the above embodiments have all been described with respect to treatment in an aerobic bioreactor, the present invention is not limited thereto, and an anaerobic bioreactor may also be used. In this case, it is necessary to cover the bioreactor, collect the gas, and heat it.

[Effects of the Invention 1 1. Since a large number of hollow fiber membranes are housed in a honeycomb tube to form a module, handling becomes easy and processing capacity can be standardized.

2. The hollow fiber membrane is no longer tangled, and its lifespan is extended.

3. Easy to incorporate into solid-liquid separation tanks and bioreactors.

4. The present invention can be applied to sewage treatment facilities, industrial wastewater treatment facilities, wastewater reuse facilities, and modification of existing treatment facilities.

[Brief explanation of drawings]

Fig. 1 is a 70-view diagram of a sewage treatment system according to an embodiment of the present invention, Fig. 2 is a top view showing a state in which honeycomb-type hollow fiber membrane modules are filled in a solid-liquid separation tank, and Fig. 3 4 is a perspective view of a hollow fiber membrane module, and FIG. 4 is a flow diagram showing another device. 1... Sand removal device, 2... Screen, 3... Bioreactor, 4... Inflow pipe, 5... Activated sludge mixture, 6... Aeration pipe, 7... Aeration blower -18...Outflow pipe, 9...Pump, 10...Screen, 11...
... Sand removal device, 12 ... Solid-liquid separation tank, 13 ... Hollow fiber membrane module, 13a ... Honeycomb tube, 13
b... Hollow fiber membrane, 13c... Suction chamber, 14... Return pipe, 15... Suction device, 16... Intermittent timer, 17... Water pipe.

Claims (1)

[Claims] 1. A bioreactor that performs biological reaction treatment on organic wastewater;
a solid-liquid separation tank into which the activated sludge mixture from the bioreactor is introduced, a hollow fiber membrane module filled in the solid-liquid separation tank, and means for intermittently sucking the inside of the hollow fiber membrane;
A sewage treatment device using a hollow fiber membrane module, comprising a timer for setting the suction time of the intermittent suction means, and means for returning the concentrated liquid in the solid-liquid separation tank to the bioreactor. 2. A bioreactor that performs biological reaction treatment on organic wastewater;
A hollow fiber membrane comprising a hollow fiber membrane module housed in the bioreactor, a means for intermittently sucking the inside of the hollow fiber membrane, and a timer for setting a suction time of the intermittent suction means. Sewage treatment equipment using thread membrane modules. 3. The above-mentioned hollow fiber membrane module is characterized in that a bundle of a large number of hollow fiber membranes for solid-liquid separation of the activated sludge mixture subjected to biological reaction treatment is housed in a honeycomb tube to freely move. A sewage treatment device using the hollow fiber membrane module according to claim 1 or 2.