WATER engineering experts have spared one of Europe’s most important chemical
plants from an expensive overhaul – thanks to an underwater cleaning robot.
Panton McLeod normally offers specialised services to the drinking water industry,
where its robot cleans water tanks without customers seeing taps run dry. Now
it has carried out a its first ever industrial project, a successful clean at
the INEOS ChlorVinyls
site in Runcorn, Cheshire with no down time.
The multi-award winning plant is one of the biggest chlor-alkali producers
in Europe. As well as producing chlorine and caustic soda, its chemicals are
used in water treatment, paper making, the food industry and making soaps and
Production depends on cooling water systems working effectively during chemical
processes and the plant has a series of water cooling towers. The water recirculation
system within the towers has to be cleaned regularly, to ensure efficiency and
to satisfy Health and Safety standards.
Plant managers normally plan months in advance to bypass the cooling towers
at huge expense in terms of materials, equipment and manpower. Now Panton McLeod
has carried out a full clean while the system remained up and running, using
the underwater cleaning robot, a mini sub and a custom-made telescopic suction
Iain Weir, managing director of Panton McLeod, said: “It has been extremely
challenging project and there were a few unforeseen obstacles along the way,
but INEOS ChlorVinyls’ people are delighted with the final results, as
“The plant is a huge concern and runs 24 hours a day, 365 days a year
and the possibility of being able to put equipment into these towers and clean
them to the highest standard without having to shut down production is the dream
Water cooling towers suck in air which is blown across droplets of heated water.
As the heat transfers to the air, it is blown up and out of the top of the tower,
while cooled water drops back down into the collection pools and is pumped back
through the plant as a coolant.
Air sucked in contains dust particles, as well as bigger debris, like leaves
and grit. That settles and forms sludge or is stirred up by turbulence affecting
the efficiency of the entire cooling process.
Panton McLeod has spent 15 years in the drinking water sector, cleaning the
huge underground tanks, called service reservoirs, which are essential to the
public supply. Its VR600 robot allows such tanks to be cleaned without shutting
of supplies to customers and still meeting the incredibly stringent purity demands
of water regulators.
The INEOS ChlorVinyls cooling tower has 14 separate water compartments and
the powerful pumps and constant falling droplets cause major turbulence and
dramatically reduced visibility, problems not encountered in drinking water
So, a mini sub fitted with powerful lights and cameras surveyed all 14 compartments
before the clean. To reach difficult areas and remove some of the larger debris,
Panton McLeod engineers designed and built a “suction boom” - a telescopic
arm with a powerful pump at the end.
They also modified the VR600 by raising its tracks and fitting a more robust
discharge hose. Water pumped out was put through settlement and filtration treatment
and returned to the cooling tower. The waste was disposed of by licensed experts.
Iain added: “The VR600 coped fantastically with the turbulence and in
the suction boom we have designed and developed an entirely new piece of equipment.
This job is a perfect case study for our ability to overcome problems. As far
the VR600 is concerned, nobody else has used this machine in this way –
it is a world first.
“INEOS ChlorVinyls has several other water cooling towers and I suspect
there will be any number of other plants who will be interested in having cooling
towers or recirculation systems cleaned without any down time. This could be
a very important shift in the emphasis of our business.”
Paul Taylor, the INEOS ChlorVinyls Site Utilities Asset Engineer, said the
site is made up of 20 separate, but interlinked production plants, served by
seven cooling towers. He added: “The cooling tower cleaned by Panton McLeod
is one of the main one cooling water to the chlorine production plant. If this
was taken out of operation it would have a dramatic impact on our chlorine production.
“We have carried out other ways to clean the tower without shutting down
production but this is by a very long way the most impressive and effective.
There was absolutely no down time, it required very little manpower from us
and it is definitely cleaned to standards to satisfy the HSE.”
Paul said the Panton McLeod method was assessed as low risk and also brought
important savings by recycling water that is already in the system. He added:
“For our point of view it has been excellent.
“I have already spoken to Panton McLeod about coming in next year to do
another tower for us and have no doubt that this will be of huge interest to
anyone who has cooling towers that cannot readily be taken out of production
without causing major and costly downtime. We are delighted.”