Surface World November 2019 Surface World November 2019 | Page 52

WATER & EFFLUENT TREATMENT
pH Neutralisation System
Many industrial processes
produce effluent which
is either too acidic or
too alkaline to be safely
discharged to drain, a piece
of process control plant
which is intercepts this
and corrects the pH to
make it safe to discharge
to drain is called a pH
neutralisation system.
Plant & Factory
Since our foundation in 1982 we’ve supplied
equipment and systems specifically for the pH
neutralisation of waste water from industrial
processes.
Working with a market leading supplier in the
surface finishing sector we were approached
to design, build and commission a pH
neutralisation system. Our customer is one of
the leading providers of surface finishing
solutions into the marine, rail and
architectural sectors. As our customer is a
supplier of numerous services, the waste-
water treatment system will in turn be
neutralising the pH from numerous
processes, which include:-
Galvanising
Chemical pre-treatment
De-ionised water regeneration
Multi-stage coarse & fine rinse water
Principle Of Operation
commissioning visit from one of our service
engineers - our customer went ahead with
this, which included:-
A commissioning visit from our service
engineers to ensure that the pH neutralisation
system is calibrated and working in the
manner specified by the customer.
The waste-water to be pH corrected is
transferred to the correction tank using air
operated double diaphragm pumps. Using a
series of level controllers and sump mounted
low level float switches the control panel calls
for the solenoid valves. These in turn control
the incoming air flow to the pneumatically
operated double diaphragm pumps which
transfer the waste-water to the mixing tank.
The pH electrode mounted inside the mixing
tank works with the pH controller to call for
either the acid dosing pump or alkaline
dosing pump to neutralise the pH in the
waste-water. The addition of the top mounted
high mixer improves the efficiency of the
chemical reagent reducing the required
contact time for neutralisation.
The system has been designed to neutralise
the pH of our customers effluent making it
compliant with the local legislation and
By carefully calculating the contact time
adhering to their consent to discharge
required at the extremes of the incoming pH
agreement. With the waste water from each
scale the volume was calculated to ensure
of the customers industrial
processes, including waste
pH Neutralisation System
water from the rinses, the
regeneration of the de-ionised
water beds and the pre-
treatment baths - all being
collected into an underground
sump.
Our customer specified that
the pH neutralisation system
should be skid mounted to
make sure that it can be easily
moved to the desired location.
All the systems that AWE
supply, including the system for
our customer are supplied:-
Complete with a full suite of
technical drawings to make
mechanical integration as
simple as possible.
Ready, wired and tested to
ensure that the onsite electrical
engineers can quickly and
easily bring the system into
operation.
When purchasing a system
from AWE we offer our
customers an optional
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NOVEMBER 2019
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