The double-area gravity-elution membrane bioreactor sewage treatment equipment
Technical field
The invention belongs to and utilize biochemical technology and membrane separation technique to handle the equipment of waste water, particularly a kind of double-area gravity-elution membrane bioreactor sewage treatment equipment.
Background technology
Membrane bioreactor is a kind of water technology that is replaced secondary sedimentation basins and sand filter in traditional biochemical processing by membrane filtration.The appearance of membrane bioreactor has improved mud-water separation efficient, simultaneously because the appearance of special efficacy bacterium (particularly dominant microflora) in the increase of activated sludge concentration and the mud in the aeration tank has improved biochemical reaction rate.Simultaneously, reduce the excess sludge generation, thereby solved the outstanding problem that the traditional biological facture exists substantially by reducing sludge loading.
Early stage separate type membrane bioreactor (see figure 4) all adopts cross-flow membrane module, promptly is filtered fluid and is parallel to filtering surface, flows with filtrate is staggered, and consequent shearing force or turbulent flows are with the thickness of restriction cake layer.In order to keep stable permeability rate, crossflow velocity is generally greater than 2m/s, and this just needs higher quantity of circulating water, causes higher unit to produce water consumption.In order to solve membrane bioreactor energy consumption problem of higher, people have researched and developed the integral type film biological reactor (see figure 5), and in integral type film biological reactor, membrane module is directly inserted in the bio-reactor, suction by vacuum pump or other types pump obtains filtered liquid; The cross-flow on film surface is produced by air agitation, aerator be arranged on membrane module under; Mixed solution upwards flows with air-flow, produces shearing force on the film surface, and under the effect of shearing force, minimizing sludge suspension particle adheres to the film surface, allows water see through.
Sludge concentration is the important parameter of membrane bioreactor system, one of key character of membrane bioreactor is a sludge concentration of utilizing the concentrated property raising bio-reactor of height of membrane sepn, thereby increase the organic matter removal ability of bio-reactor, but higher sludge concentration produces negative influence to membrane flux.Under certain condition, sludge concentration is high more, and membrane flux is lower.
Therefore, there is following shortcoming in existing integral type film biological reactor: (1) higher sludge concentration is bigger to the membrane flux influence of membrane bioreactor, has caused the processing waste water ability of membrane bioreactor to reduce; (2) higher sludge concentration is easily made film forming pollution, in order to reduce the pollution of film, needs higher aeration rate, and therefore the aeration power consumption of the unit's of processing water yield is higher; (3) membrane module is positioned at the inside of bio-reactor, not easy cleaning and maintenance.
Summary of the invention
The objective of the invention is to overcome the defective that above-mentioned integral type film biological reactor exists, provide a kind of easy and simple to handle and energy consumption is low, utilize the double-area gravity-elution membrane bioreactor sewage treatment equipment of the gravity head water outlet on membrane module top.
Equipment of the present invention is made up of upflow-type reactor and the container that is installed on the upflow-type reactor.
Described upflow-type reactor is a biochemical reaction zone, and a pipe core is installed in upflow-type reactor, between pipe core and the reactor wall space is arranged, and has water-in in the upper portion side wall of reactor.Water in the pipe core is upward flow, and to stream, mixed solution circulates inside and outside pipe core the water outside the pipe for down.
Described container is a solid-liquid displacement zone, and membrane module is installed in container, and the bottom of membrane module is laid with aeration tube; Upper portion side wall at container has inlet mouth and water outlet, and the bottom has the mixed solution admission port, and the bottom of upflow-type reactor communicates with container; Pass the sidewall of upflow-type reactor, the communicating pipe that container is communicated with the pipe core of upflow-type reactor is installed.Solid-liquid displacement zone is on the outer side wall of biochemical reaction zone bottom.
The bottom of membrane module is laid with aeration tube, and in order to wash away the film surface, the film water outlet drives continuous effluent by the gravity head of membrane module top, saves the control unit of water outlet suction pump with the water outlet at intermittence of conventional film bio-reactor.The isolating solid of tunicle under the carrying of gas by entering the pipe core of bio-reaction zone communicating pipe.
Described communicating pipe is installed in the top of container.
Between the outer wall of described membrane module and upflow-type reactor dividing plate is arranged.
Described inlet mouth is below water outlet.
Solid-liquid displacement zone of the present invention is in a container, solid-liquid separation can occur in the space below the membrane module in container, make with mixed solution that film contacts in sludge concentration reduce, alleviate the influence of sludge concentration to membrane flux.Solid-liquid displacement zone can have following two kinds of structure formations: structure one, no iris type solid-liquid displacement zone; Structure two has the iris type solid-liquid displacement zone.
The working method of double-area gravity-elution membrane bioreactor of the present invention is: city domestic sewage or trade effluent at first enter the biochemical reaction zone top that microbial population (active sludge) is housed by water-in, under the disturbance of gas with the microbial population thorough mixing; Then, mixed solution flows downward in the pipe core outside, when arriving reactor bottom, under the castering action of gas, enters pipe core, and upwards flows: at biochemical reaction zone, pollutent can be decomposed and remove.
Partially mixed liquid enters from the mixed solution admission port of solid-liquid displacement zone bottom and carries out the solid-liquid initial gross separation the solid-liquid displacement zone, reducing the solids concn of the liquid that contacts with film, thereby reduces resistance, the work period of prolongation film.
Aeration tube is laid in the bottom of membrane module, and air constantly washes away and the vibration membrane surface, and mud can not be adhered on it.
With the liquid of water inlet equivalent under the gravity head above the membrane module drives, through the membrane filtration continuous effluent, separated mud then under the rolling action of gas, by entering the pipe core of biochemical reaction zone communicating pipe, so moves in circles, waste water is purified.
Equipment of the present invention has following advantage:
1. system saves the traditional water outlet suction pump and the control unit of water outlet intermittently, and compact construction, structure is succinct, floor space is little, operation with safeguard simply, manual request is few, easily is automated control.
2. membrane module is positioned at solid-liquid displacement zone, reduces the sludge concentration of membrane separation zone and the pollution of film, improves the processing power of film.
3. solid-liquid displacement zone is communicated with the pipe core of biochemical reaction zone, realizes washing away the efficient utilization of membrane module tolerance, has improved the utilization ratio of oxygen, the required aeration rate of the normal operation of reduction system, thereby the operation energy consumption of reduction system.
4. membrane module is installed in the side of solid-liquid displacement zone, is easy to install, dismantle, and helps the maintenance and the cleaning of film.
Description of drawings
Fig. 1. the synoptic diagram of present device;
Fig. 2. the present invention is not with the solid-liquid displacement zone synoptic diagram of dividing plate;
Fig. 3. the solid-liquid displacement zone synoptic diagram of band dividing plate of the present invention;
Fig. 4. existing separate type membrane bioreactor synoptic diagram;
Fig. 5. existing integral type film biological reactor.
Reference numeral
1 water-in, 2 biochemical reaction zones, 3 pipe cores, 4 inlet mouths, 5 water outlets
6 membrane modules, 7 communicating pipe 8 mixed solution admission port
9 solid-liquid displacement zone, 10 dividing plates, 11 pumps
12 returned sluges, 13 containers, 14 upflow-type reactors
Embodiment
Embodiment 1:
One two-region gravity-elution membrane bioreactor sewage treatment equipment is made up of upflow-type reactor 14 and container 13.
Described upflow-type reactor is a biochemical reaction zone 2, and a pipe core 3 is installed in upflow-type reactor, has water-in 1 in the upper portion side wall of reactor.
Described container is a solid-liquid displacement zone 9, and membrane module 6 is installed in container 13, and the bottom of membrane module 6 is laid with aeration tube, and dividing plate 10 is arranged between the outer wall of membrane module and upflow-type reactor; Upper portion side wall at container has inlet mouth 4, on the top of inlet mouth water outlet 5 is arranged, and has mixed solution admission port 8 in the bottom of container, and the bottom of upflow-type reactor communicates with container; At the top of container, pass the sidewall of upflow-type reactor, the communicating pipe 7 that container is communicated with the pipe core of upflow-type reactor is installed, the top of solid-liquid displacement zone is communicated with pipe core in the bio-reaction zone.
Biochemical reaction zone 2 is divided into inside and outside two portions by pipe core 3 with reactor, be upward flow in the pipe core, pipe outer under to stream, mixed solution circulates inside and outside pipe core, when mixed solution flowed to the bottom of bio-reaction zone, a part entered pipe core and circulates; Another part enters solid-liquid displacement zone 9, and mixed solution obtains solid-liquid separation to a certain degree in this zone, reduces the sludge concentration that contacts with film greatly; Membrane module is installed in the mud disengaging zone, aeration tube is established in the bottom of membrane module, and the film water outlet drives continuous effluent by the gravity head of membrane module top, and separated mud enters bio-reaction zone 2 under the carrying of gas, realize that aeration rate efficiently utilizes, can reduce operation energy consumption.
To contain COD is 160-250mg/l, and SS is 40-100mg/l, and colourity 50-120 dyeing waste water doubly enters double-area gravity-elution membrane bioreactor by water-in, spoil disposal not in the whole service process, sludge concentration is 500-3000mg/l, and water temperature is 10-30 ℃, and pH is 6-9.
Wash away membrane module tolerance and enter pipe core, mud mixed liquid is mixed in biochemical reaction zone fully, and the mixed solution of whole bio-reactor all has been oxygen condition, and organism is degraded fully.Partially mixed liquid enters solid-liquid displacement zone from the inlet of solid-liquid displacement zone, and mixed solution obtains precipitate and separate preferably in the solid-liquid district, and precipitating sludge is back to the pipe core of biochemical reaction zone under the rolling action of gas.
COD is 18-48mg/l in the water outlet, and SS is not for detecting, and colourity is lower than 30 times, reaches national miscellaneous domestic water quality standard.