EcoSanRes: Practical experiences with ABR (anaerobic baffled reactor) in cold climate?
detlefwatsan
Dear Colleagues,
In textbooks I found that under European condition no practical ABR-experiences are made and known. Is this information still valid?
I am in the middle of a project constructing a DEWATS from A to Z for an isolated Care-taking Facility, by using for sewage pre-treatment, modified off-the-shelf circular (concrete) and rectangular (PE) septic tanks (total 24 m3)to build an ABR, The secondary treatment will be a vertical CW's for 30 PE.
I hope I will be ready with all the set-up by Friday this week.
For configuration purpose of ABR only, I used the guide of the BORDA-handbook by Mr. Sasse and literature from EAWAG. But the guides are all based on tropical condition only.
To be on the save side with our colder climate in the mountains, I used very conservative assumptions, e.g.: Q = 6 m3/d, COD on ABR-inlet: 800 mg/l = 160 g/PE*d and expected effectiveness only 50%, not 70-90 as in warm climate.
Pre-treatment by ABR:
- 1 h HRT, Hydraulic Retention Time in pre-settling Aerobic tank (6 m3)
- 7 baffled cambers
- 3 days (72h) HRT in ABR (18 m3)
- 0.65 -0.41 m/h up-velocity vABR in ABR
- ABR-outlet: COD 80 g/PE*d expected if ABR-effectiveness is only 50%
Effluent Pre-filter by ZABEL, USA ("Party-Filter"):
with slot size 0.4 mm, to reduce total suspended solids (TSS),to protect CW against possible clogging in many years to come.
Secondary treatment with 120 m2 vertical CW:
- 20 g/m2*d COD-reduction
- CW-outlet with COD ca. 70 mg/l expected, (<150 mg/l COD is the maximum allowed COD-level by German authorities)
To start-up the anaerobic section I will use in ABR sludge from a centralises sewage treatment and additional to speed up biological process, I purchased Effective Micro-organism (EM's) ready made, from the shelf (Internet).
Additional, 1/4 - 1/2 of the treated water (oxygen rich) will pass aerobic settling, ABR and CW, controlled by a small pump device again.
To test expected performances the COD's of In- and Out-Lets of ABR and CW will be measured every months.
Any constructive comments and discussions on that made configurations are highly welcome. Maybe useful for Mongolian condition to.
If suitable, your cold climate recommendations, will be quickly included in further hands-on modifications.
Best Regards,
Detlef SCHWAGER
MSc. Tropen-Wasserwirtschaft
AquaVerde SA
Karl Liebknecht Str. 13
D-06317 Röblingen am See
Tel.: 034774 70672
FAX: 0321210 70672
aqua-v...@email.de
