TANK CLEANING
In 2005 a sludge survey
was carried out at a UK
refinery using the Willacy
Patented Sludge Profiler for
Oil Tanks (SPOT system),
which is based on sonar.
From two entry positions on
the roof of the 73m diameter
floating roof crude oil tank,
the whole of the tank was
surveyed, while full of oil, in
less than one working day.
Almost 3,887m³ of sludge
was located and mapped in
the tank; the height of the
sludge banks was also
accurately indicated. This
allowing for careful planning
of the non-entry sludge
removal programme, says
Willacy.
The customer's technical
directive specified that for
the cleaning of crude oil
tanks “The technology must:-
require entry of cleaning
personnel inside the tank
only during the final phase
for removal of sediments
when the atmosphere no
longer demands the use of
respiratory protective devices
and thus avoiding having a
phase of work performed in
an atmosphere with
hydrocarbons that can be the
source of potential hazards.
For this purpose, automatic
hydrodynamic jetting can be
used. This breaks up the
structure of the sludge and
places the hydrocarbons in
suspension through
circulation ”.
