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July
2020
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HYDROCARBON
ENGINEERING
T
he rising costs of solids disposal demands greater
performance and efficiency from the solids
dewatering units in wastewater treatment plants.
With 40+% of the operating budget tied up in the
cost of disposing of solids, inexpensive improvements and
mechanical optimisations to the gravity drainage section
(GDS) can result in significant savings by improving the
overall performance of belt filter presses (BFPs) – and this is
with no costs after the installation and implementation of
the upgrades.
Why the belt filter press?
BFPs treat solids containing sludge from processes as varying
as mineral solids frommining sites to biological sludge
generated frommunicipal waste treatment and everything
in between. While BFPs can come in an almost infinite
number of designs and configurations, each press contains
the same three sections: GDS, wedge section, and pressure
section.
Each section plays a vital role in the removal of water
from the treated sludge, but the majority of the time spent
troubleshooting and optimising BFPs revolves around the
pressure section and dewatering aide (polymer)
optimisation. However, the biggest cost advantage is found
in optimising the GDS. With greater than 50% of the total
water removed during the entire process removal occurring
in the GDS, significant improvements in overall
performance are generated with minimal capital and
potentially no other changes to the system operationally.
In two separate wastewater systems, Athlon audited
BFPs in order to improve the produced cake dryness and
reduce the site’s overall spend surrounding the BFP systems.
One system consisted of several rows of plows used to shift
the treated sludge around the GDS and expose more belt
Troy Davis, Athlon, a Halliburton
Service, USA,
presents an overview of
how a belt filter press can be optimised
to reduce the cost of solids disposal.