1. High Rate Anaerobic Wastewater Treatment
Dr. Jim A. Field and Dr. Reyes Sierra, University of Arizona

2. What is Anaerobic Biodegradation?

3. Marsh Gas

4. COD Balance Aerobic Biodegradation

5. COD Balance Anaerobic Biodegradation

6. Overview Anaerobic Biodegradation
Polymers
(proteins, polysaccharides) h
Monomers
(sugars, amino acids, peptides) 1
Methanogenic Consortium
propionate
butyrate 2
H2 + CO2
acetate 3 4
CH4 + CO2
Hydrolytic enzymes
Homoacetogenic bacteria
Fermentative bacteria
Methanogens
Syntrophic acetogenic bacteria

7. Methanogenic Reactions

8. Kinetic Parameters Anaerobes

9. CSTR Dilution Rate (1/HRT) Time < Growth Rate
Methanosaete (td =7 d), growth rate = ln(2)/td = 0.1 d-1
so minimum HRT = 10 days

10. Recycle of Active Biomass
Dilution Rate (1/HRT) Time > Growth Rate
sludge retention time uncoupled from hydraulic retention time
Contact
Process

11. Immobilization of Active Biomass
Dilution Rate (1/HRT) Time > Growth Rate
sludge retention time uncoupled from hydraulic retention time
biogas
Anaerobic
Filter
effluent
biofilm
Support (pumice)
influent

12. Immobilization of Active Biomass
UASB

13. History Anaerobic Treatment Technology
Originally: Slurry Digestion
Manures, Sludges
60 to 80’s: Agroindustrial Effluents
Brewery, Distillery, Food Processing
80 to 90’s: Pulp/Paper Effluents
Condensates, (C)TMP, Bleachery
90’s: Chemical/Petrochem. Effluents
Terephthalate, phenols
90 to 00’s: Anaerobic Bioremediation
PCE, BTEX

14. Upward-flow Anaerobic Sludge Blanket
biogas
effluent
weir
3 phase
separator
settler
gas
cap
baffles
gas bubble
sludge granule
sludge
influent
bed

16. Expanded Granular Sludge Bed
Influent
Effluent
Recycle
Sludge
Bed
settler
gas
cap
biogas
bubble
sludge
granule
Expanded Granular Sludge Bed

17. Anaerobic Sludge Granules
Physical:
dense compact biofilms
high settleability
(30-80 m/h)
high mechanical strength
Microbial:
balanced microbial community
syntrophic partners closely associated
high methanogenic activity
(0.5 to 2.0 g COD/g VSS.d)
protection from toxic shock

18. Anaerobic Sludge Granules (close up)

19. Anaerobic Sludge Granules (SEM)
Acetate as Substrate (Methanosaeta)
Sucrose as Substrate (mixed culture)

20. Anaerobic Sludge Granules (settling)
granular
flocculent
dispersed

21. Surveyed High Rate Anaerobic Plants
Number Full Scale High-Rate Anaerobic Bioreactors
Cumulative number of high rate anaerobic treatment plants for industrial applications

22. Market-Share Granular Sludge Reactors
hybrid
anaer. filt.
fluid. bed
EGSB+UASB = 72%

23. Who Discovered the UASB?
Gatze Lettinga

24. Design Loads Full Scale
UASB & EGSB
reactor n
average design load
UASB
682
10 kg COD/m3.d
EGSB
198
20 kg COD/m3.d
Removal Efficiency of Biodegradable COD 85 to >90%

25. Most Important Markets for High Rate Anaerobic Treatment
Breweries and beverage industry
Distilleries and fermentation industry
Food Industry
Pulp and paper
These four wastewater types account for 87% market

26. New and Emerging Markets for High Rate Anaerobic Treatment
Chemical and Petrochemical
Textile Industry Effluents
Landfill Leachates
Sulfate reduction coupled to sulfur removal
Sulfate reduction coupled metal recovery

27. UASB Technology for Removal and Recovery of Metals

28. Municipal Sludge Digesters
Photo Gallery
Municipal Sludge Digesters

29. Municipal Sludge Digesters
Switzerland

30. Centralized Biogas Plant
Lintrup Biogas plant (Denmark)
animal manures

31. Anaerobic Lagoon
Food/Beverage Processing - Washington

32. Contact Process
Food-Processing, Virginia

33. UASB
The Netherlands

34. UASB - Internal Circulation
Brewery (Switzerland), 20 m height

35. UASB - Internal Circulation
Kraft Paper Mill Foul Condensates, Alabama

36. EGSB
Gist Brocades (yeast, pharmaceuticals) The Netherlands

37. Modular Design UASB Reactors