BIOLOGICAL WASTEWATER
TREATMENT TECHNOLOGIES
Course material week 9
Biological Process Technology
Environmental Engineering Dept.
Institut Teknologi Bandung
2013
Conventional Wastewater Treatment Process
Pretreatment involves:
Screening
Grit Removal
Oil separation
Flow equalization
Chemical Treatment is
used in conjunction with
the physical and chemical
processes:
Chemical precipitation
Adsorption
Disinfection can use:
Chlorine compounds
Bromine Chloride
Ozone
UV Radiation
Sludge Treatment and
Disposal involves:
grinding, degritting, blending,
thickening, stabilization,
conditioning, disinfection,
dewatering, heat drying,
thermal reduction, ultimate
disposal
General overview of plant components
Raw Wastewater Influent
PRELIMINARY
A
Preliminary Residuals
PRIMARY
(i.e., grit, rags, etc.)
Clarifier
SECONDARY
Usually to Landfill
B Primary Sludge
Biological
Treatment
System
Wastewater
Treatment
Residuals
Clarifier
Clarifier
C Secondary Sludge
Biosolids
Processing
and Disposal
(e.g., attached-grwoth
Suspended-Growth,
Constructed Wetland, etc.)
DISINFECTION
Clean Wastewater Effluent
Discharge to Receiving Waters
Biological Treatment

In the case of domestic wastewater treatment, the
objective of biological treatment is:
◦ To stabilize the organic content
◦ To remove nutrients such as nitrogen and phosphorus
Types:
Aerobic Processes
Anoxic Processes
Anaerobic Processes
Combined Aerobic-AnoxicAnaerobic Processes
Pond Processes
Attached Growth
Suspended Growth
Combined Systems
Aerobic
Maturation
Facultative
Anaerobic
Major Aerobic Biological Processes
Type of
Growth
Common Name
Use
Suspended
Growth
Activated Sludge (AS)
Carbonaceous BOD removal (nitrification)
Aerated Lagoons
Carbonaceous BOD removal (nitrification)
Attached
Growth
Trickling Filters
Carbonaceous BOD removal. nitrification
Roughing Filters (trickling
filters with high hydraulic
loading rates)
Carbonaceous BOD removal
Rotating Biological
Contactors
Carbonaceous BOD removal (nitrification)
Packed-bed reactors
Carbonaceous BOD removal (nitrification)
Combined
Suspended &
Attached
Growth
Activated Biofilter Process Carbonaceous BOD removal (nitrification)
Trickling filter-solids contact
process
Biofilter-AS process
Series trickling filter-AS
process
Major Anaerobic Biological Processes
Type of
Growth
Common Name
Use
Suspended
Growth
Anaerobic Contact Process
Carbonaceous BOD removal
Upflow Anaerobic SludgeBlanket (UASB)
Carbonaceous BOD removal
Attached
Growth
Anaerobic Filter Process
Carbonaceous BOD removal,
waste stabilization
(denitrification)
Expanded Bed
Carbonaceous BOD removal,
waste stabilization
Major Anoxic and Combined Biological
Processes
Type of
Process
Type of
Growth
Common Name
Use
Anoxic
Suspended
Growth
Suspended Growth
Denitrification
Denitrification
Attached
Growth
Fixed-film Denitrification
Denitrification
Suspended
Growth
Single- or multi-stage
processes, various
proprietary processes
Carbonaceous BOD removal,
nitrification, denitrification,
phosphorus removal
Attached
Growth
Single- or multi-stage
processes
Carbonaceous BOD removal,
nitrification, denitrification,
phosphorus removal
Combined
Aerobic,
Anoxic, and
anaerobic
Processes
REFERENSI
Wastewater Treatment Technology, Prof. George Ayoub, Faculty of
Engineering and Architecture, American University of Beirut
(www.uest.gr/.../Treatment_Technologies.PPT)