19 / 40
⎪
Pump systems, pipes, valves and seals
⎪
Mechanical Technology — March 2016
17
wastewater treatment
aeration basin reaches its limit in terms
of load.
“All wastewater plants have a limited
capacity – and if the plant exceeds its
capacity for wastewater, due to seasonal
demands, for instance, the introduction
of HP oxygen technology can serve to
augment the capacity of the basin in the
short term. This is a highly cost-effective
alternative to expanding an existing
plant’s infrastructure,” notes Kulkarni.
“Moreover,” he adds, “the use of
oxygen-based technology eliminates
wasted energy in terms of separating
oxygen from nitrogen in normal aeration
processes. Using high-pressure (HP)
oxygen also achieves faster oxygen mass
transfer rates into water, as compared
to air aeration transfer rates. Greater
oxygen solubility enhances and assists
the development of microorganisms in
effluent or sludge.”
Oxy-Dep
®
offers treatment plants a
highly efficient oxygen dissolution sys-
tem, which incorporates a side-stream
injector to deliver oxygen in the form
of very fine bubbles to an activated
sludge process, with minimal power
consumption.
“This technology is ideal when space
is too limited for the installation of a
new or additional plant, as it effectively
increases the treatment capacity of the
existing plant. This has important im-
plications in minimising the need for
large capital expenditure,” Kulkarni
emphasises.
Other specialist solutions offered
by Air Products to address specific
wastewater-related problems include
ozone technology, which the company
provides not only for water treatment but
also for cyanide destruction in the mining
industry; and carbon dioxide, which the
company supplies to water-treatment
companies for pH balancing.
Looking beyond wastewater treatment
and purification, Kulkarni notes that
aquaculture, as one of the fastest grow-
ing food-producing sectors, represents
further opportunities for the introduction
of oxygen technology.
Air Products develops and designs its
oxygen-based technologies in line with
changing markets and industry demand
for optimising efficiencies and minimising
environmental impact.
“While oxygen processes for the
biological treatment of wastewater are
not new technology, there is scope for
increased application of these tech-
nologies in the current environment. The
watchwords in industry are ‘reuse’ and
‘recycle’ – especially in the context of
water scarcity in South Africa.
“Although oxy-Dep
®
provides rec-
ognised benefits when compared to
conventional aeration methods, it is not
the final word in wastewater treatment.
Air Products is making ongoing advances
in the field through its research and
development efforts, to gain a deeper
understanding of the role of oxygen in the
biological and water treatment processes.
This will enable us to further assist
our customers in industries with specific
needs and to also address ever-present
environmental demands going forward,”
Kulkarni concludes.
q