2. INNNNTTTTRRRROOOODDDDUUUUCCCCTTTTIIIIOOOONNNN OF ACCCCTTTTIIIIVVVVAAAATTTTEEEEDDDD SLLLLUUUUDDDDGGGGEEEE
Biological Treatment Process:-
Use of Microorganisms to break down the organic matter in
wastewater
Organic Matter O2 CO2 + H2O + Energy + New Biomass
Suspended-Growth mechanisms
mechanisms:-
This process maintain a culture of organisms in suspension of
wastewater liquid, either by vigorously aerating the liquid or
by mechanical mixing.
Aerobic Bacteria grow and form particles that clump together.
These particles (flocs) are allowed to settle to the bottom of the
clarifier, leaving a relatively clear liquid free of organic material
and suspended solids after aeration process.
2
5. BAAAACCCCTTTTEEEERRRRIIIIAAAA
Composition:- C60H87O23N12P
Characteristic:-
Ability to flocculate to form floc and their separation from the
liquid phase for complete stabilization.
Removal of organic matter from wastewater is carried out
through 2 process:-
11.. BBiioollooggiiccaall OOxxiiddaattiioonn // RReessppiirraattiioonn
COHNS + 02 + BACTERIA CO2 + H2O + ENERGY + others
2. Biosynthesis
COHNS + O2 + BACTERIA C5H7NO2 (New Cells)
Examples:-
Zooglea, Bacillius spp. , Pseudomonas, Flavobacterium, Alcaligenes,
Acinetobacter 5
6. GROWTH OF BACTERIA - HHHHIIIIGGGGHHHH LLLLEEEEVVVVEEEELLLL OOOOFFFF FFFFOOOOOOOODDDD
When abundance of food is
available
Bacteria are grow, motile,
extremely active
They are multiply rapidly.
6
Bacteria will not flocculate and
settle as long as they are growing
at a lag phase.
Biosynthesis (new cell);
Respiration (energy)
Activated Sludge with a
poor settling properties
7. GROWTH OF BACTERIA - LLLLOOOOWWWW LLLLEEEEVVVVEEEELLLL OOOOFFFF FFFFOOOOOOOODDDD
When low level of food is available
The bacteria begin to conserve energy become non-motile
form
They begin to form a thick outer slime layer. As
they bump into each other, they stick together.
At first they form small clumps then masses large
enough to settle
Autoagglutination process
Biosynthesis (new cell);
Respiration (energy)
Activated Sludge with a good settling properties
7
8. FIIIILLLLAAAAMMMMEEEENNNNTTTTOOOOUUUUSSSS BAAAACCCCTTTTEEEERRRRIIIIAAAA
Characteristic:-
Filaments do not have the same flocculating characteristics
as the bacteria which do not compact to a readily settleable
mass.
Roles:-
11.. BBOODD//CCOODD rreemmoovvaall
2. Add a backbone for strengthen purpose to the floc structure
Examples of Filaments:-
S. natans,
Nocardia,
Beggiatoa…
8
9. When filaments abundant in
activated sludge:-
Foaming
Predominate over the bacteria when:-
9
1. Low Dissolve Oxygen
2. Low pH
3. Low Nutrients
4. F/M ratio not stable
5. High level of Oil Grease
10. PRRRROOOOTTTTOOOOZZZZOOOOAAAA
Roles:-
Removing digesting free-swimming dispersed bacteria
and other suspended particles. This improves the clarity
of the effluent
Biological Indicator of the activated sludge condition:-
SSttrriicctt AAeerroobbeess
More sensitive to toxic organic compound
Examples:-
1. Ciliates (Opercularia, Carchesium polypinum …)
2. Amoebae (Arcella,Euglypha…)
3. Flagellates (Peranema… )
10
11. PROTOZOA -AMMMMOOOOEEEEBBBBAAAAEEEE
Food:-
They feed on small organic particulates
When abundant present in Activated sludge:-
Plant start-up.
AA sshhoocckk llooaadd ooff BBOODD // llaarrggee aammoouunntt ooff oorrggaanniicc
particulates has entered the treatment system
They move slowly cannot compete with bacteria / protozoa for
food. Sudden increase in food allows them to compete multiply
They required less O2 able to
compete with other protozoa
when the O2 is limited.
11
12. PROTOZOA - STTTTAAAALLLLKKKKEEEEDDDD CCCCIIIILLLLIIIIAAAATTTTEEEE
Food:-
They feed on suspended bacteria, algae smaller protozoa
Stalked Ciliate dominance in the system when:-
Bacterial population and dissolved oxygen concentration of the
treatment process are high
Stalk
A mature floc structure has developed
They indicate a stable wastewater environment a healthy
activated sludge
12
Examples:-
1. Carchesium sp.
2. Suctorian
13. PROTOZOA -CCCCRRRRAAAAWWWWLLLLIIIINNNNGGGG CCCCIIIILLLLIIIIAAAATTTTEEEESSSS
Food:-
They feed on suspended bacteria, algae smaller protozoa
Characteristic:-
They are free forms, inhabit the surface of sludge flocs or
bbiiooffiillmm
They dominance in the system when:-
After most soluble nutrients have been removed which are
reflect a stable wastewater
environment healthy
activated sludge
13
14. METAZOA
They are multicellular organisms include all animals
except the protozoa
Roles:-
Feed on bacteria, bacteria floc, fungi, protozoa
rotifer
EExxaammpplleess::--
Nematode worms (Genus Aelosoma, Rhabditis)
Rotifers
Tartigrades (water bear)
14
15. METAZOA - ROOOOTTTTIIIIFFFFEEEERRRR
Roles:-
Feed on good, stabilized floc; They graze on the floc
structure and increase oxygen penetration
As environmental indicator due to they are usually the first
to be affected by a toxic load.
When abundant present in activated sludge:-
Old sludge age with high MLSS
Low F/M ratio
15