A kind of active sludge filtration unit
Affiliated technical field:
The utility model relates to active sludge filtration unit in a kind of sewage disposal, and this device is used for substituting traditional second pond and carries out the active sludge mud-water separation;
Background technology:
Traditional sewage water treatment method adopts activated sludge process more, sewage is after handle the active sludge aeration tank, enter second pond (the SBR pond is that mud-water separation is carried out in the aeration tank) and carry out mud-water separation, restriction owing to hydraulic load that can bear by second pond and sewage sludge solid load, sludge concentration in the aeration tank is difficult to improve, sludge concentration in traditional activated sludge process aeration tank generally is lower than about 4g/l, cause the surface-area of aeration tank volume increase and second pond bigger, thereby increased sewage work's construction investment and floor space; In addition, because the mud flco is lighter, in water factory's operational process, sludge bulking taking place easily, can cause mud to run off from second pond, brings bigger difficulty for sewage work's operational management.
Occur adopting ultrafiltration or microfiltration membrane to replace second pond in recent years, because ultra-filtration membrane or microfiltration membrane unit surface water flux are relatively low, thereby the film device surface-area of handling the unit sewage quantity is big, resistance is bigger during the film operation, resistance reaches as high as 5-8m during the film operation, cause the operation energy consumption height, need regular matting just the efficient recovery water flux can be arranged.The membrane module expense is higher; cause the membrane treatment appts construction investment obviously to increase than conventional process technology; thereby the application of membrane Bio-reactor Technology is restricted; substitute traditional second pond as simple and effective way how; to increase the sludge concentration of aeration tank, help reducing the volume and the floor space of aeration tank, improve sewage treating efficiency; reduce energy consumption, the protection environment has vital role.
Summary of the invention:
Low for overcoming in the active sludge treatment process second pond load, mud runs off easily, the big shortcoming of floor space, the utility model provides a kind of active sludge filtration unit, this device is used for substituting traditional second pond and carries out mud-water separation, can prevent effectively that active sludge runs off, thereby sludge concentration in the raising aeration tank overcomes the some shortcomings that have second pond now;
The technical scheme that its technical problem that solves the utility model adopts is: filtration unit comprises one or more filtering units, filtering unit is by filtering net, permeable supporting layer, perforation header support, collection pipe, air releasing tube is formed, flushing air perforations pipe is set between filtering unit, filter screen back flushing water pipe is set simultaneously, it is characterized in that: each filtering unit is a tabular, outside stainless steel or the filter cloth filter screen parcel of adopting, the filtering net aperture is 10~200 μ m, adopt permeable supporting layer between filter screen, support adopts the perforation header all around, forming the activated sludge biological film filtering layer on screen surface filters, water filters the back through filtering layer and enters header all around again by permeable supporting layer, header is collected to collection pipe and is discharged by filter outlet pipe, on filtering unit top air releasing tube is set, strainer adopts periodic duty, strainer is after operation for some time, the accumulation of screen surface mud, the filtering layer resistance increases and water flux reduces, this moment need be to the strainer back flushing, back-flushing method is that utilization back flushing air of perforated pipe between filtering unit is cleaned screen surface, by the reverse water of header filter screen is washed simultaneously, to recover the filtering function of strainer.
The beneficial effects of the utility model are, by the active sludge strainer mud is trapped in the aeration tank, sludge concentration improves greatly than sludge concentration in the conventional activated sludge method aeration tank in the aeration tank thereby make, can significantly reduce pool volume and floor space, save construction costs, there are not sludge bulking and second pond sludge loss problem in the traditional active sludge treatment plant operational process, because the strainer screen aperture is bigger, the resistance of strainer is below 0.5m, and unit screen area water flux can reach 1001/h.m
2More than, be applicable to that high-concentration activated sludge filters, this strainer is big except that water flux, filtration resistance low owing to adopt stainless steel or filter cloth strainer filtering, the expense of filtration unit reduces greatly, effectively saves construction investment and reduces working cost.
Description of drawings
Below in conjunction with drawings and Examples the utility model is further specified.
Fig. 1 is first embodiment orthographic plan of the present utility model.
Fig. 2 is first embodiment A-A sectional view.
Fig. 3 is another embodiment sectional view of the utility model
Permeable supporting layers 4 perforation of 1 filtering unit, 2 filtering nets 3 support that catchments among the figure
5 collection pipes, 6 rising pipes, 7 back flushing water pipes, 8 air releasing tubes
9 perforated pipes, 10 strainer pond bodies, 11 filtering unit supports, 12 mixed solutions enter pipe
13 mud return lines, 14 aeration tanks, 15 aeration tubes, 16 excess sludge discharge pipes
17 excess sludge discharge pipes
Embodiment
Fig. 1, in 2, active sludge enters pipe (12) by mixed solution and enters strainer pond body (10) in the aeration tank, strainer pond body (10) is interior according to the filtering unit (1) of handling the flow set some amount, filtering unit (1) adopts support (11) to support, filtering unit (1) outside is stainless steel or filter cloth filter screen (2), the filter screen mean pore size is 10~200 μ m, filtering unit (1) is a tabular, be provided with permeable supporting layer (3) and the perforation support (4) that catchments in the filtering net (2), between filtering unit (1), be provided with air perforations pipe (9), each filtering unit bottom is connected to collection pipe (5), and collection pipe (5) is connected with backwash water pipe (7) with rising pipe (6).
Under normal operation, form microbial film on filter screen (2) surface, sewage under action of gravity after filter screen (2) filters, water is catchmented by permeable supporting layer (3) to perforation in the support (4), finally compile after rising pipe (6) discharging by collection pipe (5), active sludge is trapped within the body of pond, be back to the aeration tank by mud return line (13), excess sludge discharges by excess sludge discharge pipe (14), the air that gathers in the filtering unit is discharged by air releasing tube (8), strainer adopts periodic duty, strainer is after operation for some time, filtration resistance increases and water flux reduces, this moment need be to filtering net (2) back flushing, back-flushing method is that utilization back flushing air of perforated pipe (9) between filtering unit is cleaned screen surface, by the reverse water of back flushing water pipe (7) filtering net (2) is washed simultaneously, to recover the filtering function of strainer.
In another example shown in Figure 3, filtering unit (1) is placed directly in water inlet mud-water separation in the active sludge aeration tank (14), active sludge is trapped in the aeration tank (14), aeration tube in the aeration tank (15) oxygen supply, excess sludge is discharged by shore pipe (16), handles the back water outlet by rising pipe (6) discharging;