Anaerobic aerobic flocculation precipitation sewage treatment process
Technical field
The present invention relates to technical field of sewage, particularly a kind of anaerobic aerobic flocculation precipitation sewage treatment process.
Background technology
In existing sewage treatment technology, special anaerobic film bed is a kind of anerobic sowage treatment technology efficiently, and it has startup soon, and mud is difficult for running off, and can select the advantages such as filler of unlike material for use, but also have long reaction time, the shortcoming that pool volume is big; BAF also is a kind of aerobic sewage treatment technology efficiently, and the BAF biggest advantage is to integrate bio-oxidation and hold back the suspended solids function, has saved second pond; In addition, this treatment process has also that volumetric loading is big, hydraulic load is big, and floor space is little, initial cost is few, the oxygen transfer rate height, characteristics such as effluent quality is good, but it also exists the concentration of suspension SS to water inlet to have relatively high expectations, head loss is bigger, needs regular back flushing; Flocculation sediment is a kind of very sophisticated sewage purification treatment technology, and easy realization simple to operate can be selected different coprecipitation modes, can select the most effective flocculation agent according to water quality.A kind of " artesian sewage treating process " disclosed in number of patent application is 00110777.1 application for a patent for invention, comprise eddy flow desanding, anaerobic biological treatment, aerobe processing, sedimentation water outlet etc., it is characterized in that sewage passes through anaerobic digester, lower clapboard on the staggered multiple tracks is set in anaerobic digester, the degradation biological film is set, covering and heat insulating layer on the pond in the pond simultaneously; High scale software microbial film is set in aerobic digestion tank, carries out active sludge and separate under aeration condition, the settled sludge in this pond all is back in the anaerobic digester, mixes with anaerobic sludge; The advantage of this technology is based on anaerobic degradation, is auxilliary with aerobic degradation, and muddy water is close-coupled processing, reduces facility investment and working cost; But also there is following shortcoming in it: technology is not too reasonable, and the anaerobic digestion effect is bad, and rate of load condensate is low, and initial cost is big, and the Aerobic Pond sludge output is big, and is unrealistic on recycling sludge at present.
Summary of the invention
The objective of the invention is to special anaerobic film bed anaerobic biological treatment, the processing of BAF aerobe and three kinds of sewage treatment process of flocculation dephosphorization precipitation technology are combined, a kind of anaerobic aerobic flocculation precipitation sewage treatment process reasonable, that processing efficiency is high, energy consumption is low, sludge quantity is few, working cost is low that makes up is provided.
In order to achieve the above object, the present invention realizes by following scheme: this anaerobic aerobic flocculation precipitation sewage treatment process may further comprise the steps: sewage is earlier through grid, drive by water pump behind the pump well and carry out anaerobic biological treatment to special anaerobic film bed after entering cyclone-type sand precipitating pool, sewage after anaerobic treatment flows into BAF again and carries out the aerobe processing, can remove most organic pollutants through the Two-Stage Biochemical processing, be back to special anaerobic film bed by the BAF water part, make special anaerobic film bed not need other supplementary carbon source to carry out denitrogenation to sewage, form good denitrification process, outputted aerobic water is again through the flocculation reaction deposition dephosphorization.In whole technological process, denitrogenation is relative with dephosphorization simple independent, has realized highly effective dephosphorizing denitrification.
Described sewage is 2~8 hours in the residence time that special anaerobic film bed carries out anaerobic biological treatment, and the volumetric loading of special anaerobic film bed is 1.2~3.6kgCOD/m
3.d; The residence time that sewage carries out the aerobe processing in BAF is 1~4 hour, and the volumetric loading of BAF is 2.4~7.2kgCOD/m
3.d, gas-water ratio is (1.5~5): 1; The flocculation reaction time is 10~30 minutes, and sedimentation time is 1~3 hour, surface load 1~2m
3/ m
2.h.
This technology also comprises regularly carries out back flushing to BAF, and backwashing water enters special anaerobic film bed with raw waste water after flowing out from BAF after cyclone-type sand precipitating pool mixes.
Described special anaerobic film bed inside is provided with the anaerobism filler, and the anaerobism filler can adopt materials such as asbestos waved plate, elasticity of plastics 3-D filler, combined stuffing; BAF inside is provided with aerobic filler, and aerobic filler can adopt materials such as Biohaydite filter material, volcanics, coke, quartz sand, gac, expansion silico-aluminate, polystyrene.
The flocculation agent that described flocculation reaction is adopted can be aluminium system, ferric flocculant and compound coagulant.
The action principle of this anaerobic aerobic flocculation precipitation sewage treatment process is: adopt the combination of special anaerobic film bed and BAF that sewage is carried out degradation of organic substances and denitrogenation processing; Handle last qualified discharge again through the flocculation sediment dephosphorization.Wherein, general two stages of experience of the working process of special anaerobic film bed biological treatment, be acidication stage (fs) and product methane phase (subordinate phase), by the acidication bacterium solvability larger molecular organics in the waste water is resolved into higher lipid acid, glycerine, amino acid, monose, alcohols, carbonic acid gas, ammonia, hydrogen etc. the treatment stage of acidication, simultaneously insoluble organism is resolved into the solubility small organic molecule; Produce methane phase promptly by methanogen with simple substrate, be converted into methane as acetate, methyl alcohol and carbonic acid gas and hydrogen, this shows that special anaerobic film bed has improved the biodegradability of sewage when disposing of sewage, handle for follow-up aerobe and created favourable condition.
BAF aerobe treating processes is: the less particulate filter of a certain amount of particle diameter of filling in the filter tank, the filter material surface microbial film of growing, the inner aeration in filter tank, when effluent stream through the time, utilize on the filtrate the strong oxidative degradation ability of high-concentration biological film amount that sewage is carried out fast purification, this is the oxidation degradation process; Simultaneously, because of effluent stream through the time filtrate be compaction state, utilize particle diameter of filter medium features of smaller and biomembranous biological flocculation can hold back a large amount of suspended substances in the sewage, and guarantee that the microbial film that comes off can not drift out with water, this is to hold back process; Behind the operation certain hour, because of the increase of head loss, need to carry out back flushing to the filter tank, the suspended substance of holding back with release also upgrades microbial film, and this is a backwash process; In general, BAF has following feature: (1) uses particulate filler as bio-carrier, as haydite, coke, quartz sand, gac etc.; (2) be different from general biological filter and biological filtering tower combined working, when removing BOD, ammonia nitrogen, need carry out aeration; (3) high hydraulic load, high volumetric loading and high biomembrane activity; (4) have oxidation degradation and the dual-use function of holding back suspended substance, do not need to establish again secondary sedimentation basins after the biological processing unit; (5) need regularly carry out back flushing; Clean the suspended substance of holding back in the filter tank, upgrade microbial film simultaneously.
This anaerobic aerobic flocculation precipitation sewage treatment process will be carried out a biological disposal upon and materialization treatment process organic assembling is got up effectively handles sewage; Biochemical treatment employing special anaerobic film bed and aerobic aeration biological filter can remove the most of pollutent (chemical oxygen demand COD in the sewage
Cr, biological oxygen demand BOD
5, ss suspended solid) and ammonia nitrogen (NH
4 +-N); The materialization processing section is to utilize flocculation agent that sewage is carried out precipitating the purpose that can reach dephosphorization behind the enhanced coagulation; If no dephosphorization particular requirement treatment stage of then saving materialization, can form a kind of simple and practical technology that only keeps the anaerobic-aerobic processing section.
The present invention compared with prior art has following advantage:
(1) this anaerobic aerobic flocculation precipitation sewage treatment process is auxilliary based on special anaerobic film bed, BAF with flocculation sediment, compares with traditional waste water treatment process, and dephosphorization denitrogenation independently carries out, and it is little to influence each other, and can reach the ideal dephosphorization removing nitric efficiency.
(2) main part of this anaerobic aerobic flocculation precipitation sewage treatment process is special anaerobic film bed and BAF technology, starts soon, and stable, hydraulic detention time is short, and sludge age is long, the nitric efficiency height; Be precipitated as with the flocculation dephosphorization auxilliary, dephosphorization effectively, whole process flow is simple, operation is implemented more convenient.
(3) this anaerobic aerobic flocculation precipitation sewage treatment process adapts to the sewage of different pollution loads (as pollution level is COD
Cr=100~800mg/L, BOD
5=50~500mg, NH
4 +-N<45mg/l, among T-P<7mg/L, the sanitary sewage of lower concentration) treating processes, the processing efficiency height, the water quality of its treat effluent can reach national sewage comprehensive discharge primary standard (GB 8978-1996), chemical oxygen demand COD in the concrete effluent quality index
Cr<70mg/l, biological oxygen demand BOD
5<20mg/l, ammonia nitrogen NH
4 +-N<15mg/l, T-P<0.5mg/L chemical oxygen demand COD
Cr, biological oxygen demand BOD
5All can reach more than 85% ammonia nitrogen NH with the ss suspended solid clearance
4 --N clearance can reach more than 75%, and the clearance of total phosphorus is greater than 80%.
Description of drawings
Fig. 1 is the process flow sheet of anaerobic aerobic flocculation precipitation sewage treatment process of the present invention.
Fig. 2 is another process flow sheet of anaerobic aerobic flocculation precipitation sewage treatment process of the present invention.
Embodiment
Below in conjunction with accompanying drawing the present invention is done further concrete description, but embodiments of the present invention are not limited thereto.
Embodiment 1
Anaerobic aerobic flocculation precipitation sewage treatment process embodiment sewage disposal main part of the present invention is square concrete structure, mainly includes cyclone-type sand precipitating pool, special anaerobic film bed, BAF, flocculation reaction district, vertical sedimentation basin, sludge thickener; Cyclone-type sand precipitating pool is the whirlwind-type structure, works part particulate matter, the effect of regulating pondage water quality of removing; The special anaerobic film bed bottom is provided with sewage water distributor and filler support, and places the anaerobism filler; The BAF bottom is provided with backwash tube (being rising pipe), filter plate, aeration tube and places biofilter material, and water inlet pipe and back flushing rising pipe are arranged at top; The flocculation reaction district adopts hipped plate construction; Vertical sedimentation basin has effluent weir, guide shell, water inlet pipe, plays precipitating action, and sludge thickener plays the thickened sludge effect.Sewage treatment systems also comprises pump well, clean water basin, sludge treating system etc.
The detailed process of the anaerobic aerobic flocculation sewage treatment process of being realized by said structure is as shown in Figure 1: sewage enters cyclone-type sand precipitating pool and removes the part suspended substance through driving by water pump behind grid, the pump well earlier, and sewage enters special anaerobic film bed by water distributor and carries out anaerobic biological treatment and remove part pollutent (COD then
Cr, BOD
5), sewage is 2~8 hours in the residence time of special anaerobic film bed, the volumetric loading of special anaerobic film bed is 1.2~3.6kgCOD/m
3.d; Enter BAF from the effusive water of special anaerobic film bed and carry out the aerobe processing, further remove pollutent (COD
Cr, BOD
5), sewage is 1~4 hour in the residence time of BAF, the volumetric loading of BAF is 2.4~7.2kgCOD/m
3.d, gas-water ratio is (1.5~5): 1; Water outlet enters flocculation tank after BAF is handled, precipitate at vertical sedimentation basin then, orthophosphoric acid salt reaction in flocculation agent and the water generates phosphoric acid salt flocs unit precipitation, improve dephosphorizing rate, and can further remove suspended substance in the water, the flocculation reaction time is 10~30 minutes, and sedimentation time is 1~3 hour, and flocculation agent can adopt aluminium system, ferric flocculant and compound coagulant; The water that comes out from vertical sedimentation basin is qualified water, and the mud of vertical sedimentation basin is discharged to sludge thickener, and after the mud after concentrating was handled with the sludge treating system plate-and-frame filter press again, the dewatered sludge outward transport was further disposed.
The BAF water part is back to special anaerobic film bed, and reflux type is: the BAF water outlet is mixed into special anaerobic film bed with pump and raw waste water, and recirculation water makes special anaerobic film bed not need under the supplementary carbon source sewage to be carried out denitrogenation, improves nitrogen-removing rate.
The backwashing water of BAF flows into cyclone-type sand precipitating pool again after the filter back washing rising pipe comes out, and handle after raw waste water mixes again.
The influent concentration of this anaerobic aerobic flocculation precipitation sewage treatment process (water inlet is after cyclone-type sand precipitating pool is handled): chemical oxygen demand COD
Cr<400mg/L, biological oxygen demand BOD
5<100mg/L, ss suspended solid<200mg/L, ammonia nitrogen NH
3-N<30mg/L, total phosphorus T-P<4mg/L.
Water outlet monitoring result: chemical oxygen demand COD
CrRemain essentially in below the 80mg/L, its clearance reaches more than 90~95%; Biological oxygen demand is at BOD
5Below 20mg/L, its clearance reaches more than 95~97%; Ss suspended solid is less than 60mg/L; Ammonia nitrogen NH
3-N is below 15mg/L, and its clearance reaches more than 80%, total phosphorus T-P<0.5mg/L, and its clearance reaches more than 85%.It is 1000m that the day of this anaerobic aerobic flocculation precipitation sewage treatment structure is handled the water yield
3/ d.
Embodiment 2
Fig. 2 shows another technical process of anaerobic aerobic flocculation precipitation sewage treatment process of the present invention, this technical process is applicable to the sewage disposal that phosphorus content is lower, detailed process is: sewage is handled the back through oil removal and is driven by water pump after earlier through grid, pump well and enter cyclone-type sand precipitating pool and remove the part suspended substance, and sewage enters special anaerobic film bed by water distributor and carries out anaerobic biological treatment removal part pollutent (COD then
Cr, BOD
5), sewage is 2~8 hours in the residence time of special anaerobic film bed, the volumetric loading of special anaerobic film bed is 1.2~3.6kgCOD/m
3.d; Enter BAF from the effusive water of special anaerobic film bed and carry out the aerobe processing, further remove pollutent (COD
Cr, BOD
5), sewage is 1~4 hour in the residence time of BAF, the volumetric loading of BAF is 2.4~7.2kgCOD/m
3.d, gas-water ratio is (1.5~5): 1; Water outlet after BAF is handled is qualified water.
The influent concentration of this anaerobic aerobic flocculation precipitation sewage treatment process (water inlet is after oil removal is handled): chemical oxygen demand COD
Cr<800mg/L, biological oxygen demand BOD
5<500mg/L, ss suspended solid<300mg/L, ammonia nitrogen NH
3-N is more than 80mg/L, and a day processing water yield is 100m
3/ d.
Water outlet monitoring result: chemical oxygen demand COD
CrRemain essentially in below the 80mg/L, its clearance reaches more than 90~95%; Biological oxygen demand is at BOD
5Below 20mg/L, its clearance reaches more than 95~97%; Ss suspended solid is less than 60mg/L; Ammonia nitrogen NH
3-N is below 15mg/L, and its clearance reaches more than 80%.