HYDROCARBON
ENGINEERING
38
be carried out promptly so the vessel can move to its
next assignment. If the piping manifold extending to
the dock is down because of a valve or pump failure,
it is a major problem for everyone. An effective
maintenance programme using diagnostic information
from smart field devices, valve controllers and
monitoring sensors helps predict and prevent failures
and ultimately unplanned delays.
Moving product out of the facility includes its own
set of challenges. Customers wanting specific fuels or
chemicals do not make logistical plans for the benefit of
the terminal. Trucks and railcars do not always show up
at the time scheduled or in the order expected, so the
terminal may have to make last minute changes to keep
things moving. Some additional considerations for
operators are outlined below:
n
High accuracy volume measurements: load out is
virtually always a custody transfer, so this last
outbound measurement has to be precise and
unquestioned. Whether by truck, vessel or pipeline,
all parties to the transaction must agree on the
amount changing hands.
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Clear and immediate transfer documentation and
billing: once the product moves, the paperwork,
either printed or electronic, should be complete and
ready on the spot.
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Fast and positive vehicle identification: the ability to
identify a vehicle and its driver is an important
element of internal control mechanisms.
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Batch control for final blending: some products are
blended as they are loaded. The ability to control
this process quickly and accurately ensures
deliveries on time with products meeting
specification. In-line blending also creates
opportunity by freeing up storage that may have
been used for in tank blending.
Effective automation can simplify these processes to
confirm the right blend of product is delivered at the
right time to the right vehicle in every situation. Loading
facility time can be scheduled accurately and efficiently
to avoid time wasting stack-ups. Deliveries satisfy all the
parties to a transaction and all documents, printed and
electronic, are included. The ultimate result is a higher
load out volume, handled quickly and efficiently with a
minimum of labour and confusion.
Automation in action
Say a terminal loading facility could shorten turnaround
times, increase throughput, reduce energy consumption
and essentially stop vapour emissions entirely – all
without adding staff. Is this too good to be true?
A major loading facility at a refinery and chemical
processing facility in northern Europe did all those things
and more, and automation was a major part of the
improvements. A third party, Logistic Services, owns and
operates the terminal for the customer, and works with
Emerson Process Management to provide advanced
automation systems. The customer gave the operator a
free hand in the design process, provided it met a list of
critical requirements related to performance and
environmental considerations. For example:
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Unrecovered hydrocarbon vapour emissions have to
be below the customer's standards.
n
The operator was liable for penalties if a truck cannot
be loaded within a two hour window due to an
operational failure.
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The operator was responsible for maintenance, but it
has no technicians on the site so Emerson performs
most of the actual maintenance and repair work.
So how does this facility operate?
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When a tanker arrives for loading, drivers and plant
operators follow an automated series of safety steps.
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Vapours captured by the recovery system are burned
to generate all the electricity needed for the terminal.
n
Critical scheduling capabilities have reduced the
normal turnaround time for a typical tanker truck
from three hours to two.
Emerson’s SmartProcess TMS (Terminal Management
Solution) interfaces with the customer’s sales order
system and transmits information to the tank farm’s
automation system. Drivers receive transport requests
from the customer's ERP system automatically, providing
a time slot at the gantry. All the ‘paperwork’ is thus
electronically prepared before the truck even arrives.
With tight schedule control and a condition-based
maintenance planning programme, equipment is kept
running and repairs are performed when they will cause
the least disruption. The operator requires Emerson to
maintain a 99.7% availability level for its equipment, which
means over a year there must be fewer than three outages
of four hours each. This availability includes gantry
automation, gantry electrical controls, slot planning, and
communication with the customer's ERP system.
This automation programme has reduced the need for
human resources in an area where finding qualified people
is a serious challenge. The terminal now has a staff of six
operators rather than the 10 on the payroll before the
automation system installation. The benefits have also
been pushed upstream, as the customer says it now
spends about 20% fewer administrative man-hours
processing transactions thanks to the more refined
information it gets from the automated systems.
Conclusion
The overall oil and gas supply chain is hugely complex,
and tank farms and terminals can make or break the
profitability picture for customers and operating
companies alike. Efficient movement of products, by
whatever transport mechanism appropriate, ensures
adequate supplies and stable markets. The processes
necessary to operate terminals efficiently are not
conceptually complex, but they can be difficult to
execute manually day in and day out.
Automation systems can handle these functions
reliably and easily, and the more the various aspects are
integrated, the better the overall performance. Piecemeal
automation solutions can exhibit many of the same
drawbacks of manual approaches, so the greatest benefit,
as the customer realised, is found when using a single
supplier capable of deploying a truly integrated approach
from the enterprise level to loading gantry.
T&T
