Features: Features: - Tanker Operator

closed gauging
The HERMetic
UTImeter Gtex is a
portable electronic
level gauge for closed
gas tight operation.
The unit is used for custody transfer,
inventory control measurement and
free water detection on marine vessels.
Connected to a HERMetic vapour control
valve, the UTImeter Gtex avoids
any gas release during operation and
enables 3, optionally 4 measurements
in one single operation, Ullage,
Temperature, Oil-water interface level
and Innage.
We help you to protect the operator
and the environment.
TECHNOLOGY - VAPOUR CONTROL
The absorbtion process shown
schematically.
common inert gas pipe and
deposited at the bottom of one
cargo tank. The system can be
installed in a normal drydocking
and has a payback time of about
six months due to the increased
cargo deliveries.
For ships not engaged in
shuttle trades, a portable solution
for the transfer and loaded
voyage has been devised. This is
where Mariflex comes in,
supplying hardware, power packs
and the operational expertise.
Dr Haagensen pointed out that
sulphuric gases in empty tanks
cannot be removed by using any
on board recovery process.
Odour and H2S concentrations
usually beyond 10 ppm force
ships that have discharged sour
crudes to anchor offshore and
purge their tanks before they are
allowed to load. This timeconsuming
purging can only be
avoided if the ship loads at a
port, which has a large-scale
vapour recovery unit with gas
separation. In terms of
hydrocarbon emissions, offshore
purging only removes the peak
local load of ground level ozone
and by no means negates the
detrimental effects of ozone on
plant growth and their CO 2
uptake capacity.
Having said that, the good
news is that during loading, the
release of H2S is reduced by
20%-40% through the use of
backpressure.
Although the cost of large
vapour recovery processes and
their infrastructure may seem
prohibitive, Venturie regards them
as a final and necessary step to
minimise hydrocarbon and H 2 S
emissions in ports and designated
lightering areas. For such
lightering spots, Dr Haagensen
suggested that port authorities
should consider barge mounted
recovery units, similar to those
installed on the decks of North
Sea shuttle tankers.
TO
For more information visit our website
www.tanksystem.com or call +41 26 919 15 00
© 2008 Honeywell International, Inc. All rights reserved
Time-pressure diagram for an STS transfer with vapour return.
Vapour growth may induce gas release, but vapour reabsorption
will reduce the flow. Controlled gas release is important to reduce
vapour surges from the oil.
28
TANKEROperator March 2008