The biology in biological treatment plants
ment. It is thus possible to contract a wastewater-borne disease, even without being
in close contact with the wastewater itself.
The organisms in a biological treatment plant can be divided into the following
groups /1/:
a.
bacteria
b.
fungi
c.
algae
d.
protozoa
e.
metazoa
The two main types of biological treatment plants: biofilters and activated sludge
plants, offer different conditions of living which are reflected in the biology in the
two places. The most varied animal life is found in biofilters. Due to the design and
operation of these filters, they have very different environments where very different animals can flourish. In activated sludge plants the animals are evenly distributed and are not nearly as varied in terms of species.
Bacteria
Fungi
Algae
Protozoa
Metazoa
56
occur in large numbers both in biofilters and in activated sludge
plants. There are relatively more bacteria in activated sludge plants.
The main task of the bacteria is the primary transformation and
degradation of dissolved organic matter. Furthermore they contribute to the degradation of suspended organic matter through the
production of extracellular enzymes (exoenzymes). The content of
bacteria in activated sludge is 10 10 -10 12 per litre /3/.
must compete for food with the bacteria, and this competition
normally turns out to the advantage of the bacteria, and hence many
more bacteria than fungi are found.lf the pH in the plant is low, this
will, however, favour the fungi. Relatively more fungi are present in
biofilters than in activated sludge plants.
are found in the surface of biofilters where the conditions are good
(light and food) and in algae ponds and polishing ponds.
are common in biofilters. In activated sludge plants they occur in
varying numbers depending on the loading of the plant. A low-loaded
plant will have many protozoa in the activated sludge. The protozoa
graze on the bacteria, eat fungi, algae and suspended organic matter
and fulfil an important role for the secondary settling of the wastewater.
are higher animals. They have a distribution pattern corresponding
to that of the protozoa, that is, they occur in biofilters and in
low-loaded activated sludge plants. Many species may occur, such
as Rotifers, Crustaceans, animals and insects.
ment. It is thus possible to contract a wastewater-borne disease, even without being
in close contact with the wastewater itself.
The organisms in a biological treatment plant can be divided into the following
groups /1/:
a.
bacteria
b.
fungi
c.
algae
d.
protozoa
e.
metazoa
The two main types of biological treatment plants: biofilters and activated sludge
plants, offer different conditions of living which are reflected in the biology in the
two places. The most varied animal life is found in biofilters. Due to the design and
operation of these filters, they have very different environments where very different animals can flourish. In activated sludge plants the animals are evenly distributed and are not nearly as varied in terms of species.
Bacteria
Fungi
Algae
Protozoa
Metazoa
56
occur in large numbers both in biofilters and in activated sludge
plants. There are relatively more bacteria in activated sludge plants.
The main task of the bacteria is the primary transformation and
degradation of dissolved organic matter. Furthermore they contribute to the degradation of suspended organic matter through the
production of extracellular enzymes (exoenzymes). The content of
bacteria in activated sludge is 10 10 -10 12 per litre /3/.
must compete for food with the bacteria, and this competition
normally turns out to the advantage of the bacteria, and hence many
more bacteria than fungi are found.lf the pH in the plant is low, this
will, however, favour the fungi. Relatively more fungi are present in
biofilters than in activated sludge plants.
are found in the surface of biofilters where the conditions are good
(light and food) and in algae ponds and polishing ponds.
are common in biofilters. In activated sludge plants they occur in
varying numbers depending on the loading of the plant. A low-loaded
plant will have many protozoa in the activated sludge. The protozoa
graze on the bacteria, eat fungi, algae and suspended organic matter
and fulfil an important role for the secondary settling of the wastewater.
are higher animals. They have a distribution pattern corresponding
to that of the protozoa, that is, they occur in biofilters and in
low-loaded activated sludge plants. Many species may occur, such
as Rotifers, Crustaceans, animals and insects.