Hydrocarbon Processing - January 2022 - 20

Sustainability
FIG. 6. Coriolis technology is usually the best choice for true mass flow
readings used for mass balance calculations.
temperature, and calculate the mass flowrate. This works only
when there is a temperature reading at the flowmeter, which
can be part of the flowmeter or captured nearby.
For facilities and production units where there is a large installed
base of dP flowmeters, there is likely a mix of reliable
vs. problematic installations. Most dP installations can be improved
by verifying some basic operational and maintenance
considerations, including:
* How old is the transmitter? Today's dP transmitters
have capabilities that were not necessarily available just
a few years ago. This inexpensive upgrade can add new
multivariable functions to an existing installation.
* Are the impulse lines easy to maintain? Poorly designed
impulse lines can leak or clog, interfering with accurate
measurements. Where sediment is a problem, they can
be configured for easy clean-out.
* What is the orifice plate condition? Users should verify
that the orifice edges are still sharp, the orifice is centered
and it has not gotten larger due to wear. A micrometer
check can be made to verify that it has not lost surface
area, which would change the beta ratio.
* Does the installation have sufficient straight piping?
To achieve full accuracy, dP flowmeters need straight pipe
sections upstream and downstream from the orifice plate.
Verify that all installations include the required length.
* When was the transmitter last calibrated? Perform
whatever calibration actions are called for and check
that the ranging is still appropriate for the application.
Benefits realized from mass balance efforts. Efforts
designed to improve mass balance following the methods discussed
can deliver major improvements to refineries. The following
are three brief examples:
* With its existing measurement system, one refinery
was unable to meet the ±2% target in its crude
distillation/vacuum distillation unit. It was using dP
flowmeters and one ultrasonic insertion flowmeter.
It replaced 10 of the dP installations with Coriolis
flowmeters, and it was then able to bring the unit
20 JANUARY 2022 | HydrocarbonProcessing.com
FIG. 7. A master plan ties together all elements of an efficiency project
to maximize total benefits.
quickly and consistently within a ±1% target.
* A refinery in eastern Europe could not exceed 96%
mass balance closure using dP flowmeters, even though
they had been very fastidious about maintenance and
calibration. They replaced nine of the most critical
positions with Coriolis flowmeters. Not only did they
reduce time spent on maintenance, but they were also
able to improve mass balance to 99.4%.
* Another refinery had trouble stabilizing its hydrocracker
due to feedstock variability. Using conventional dP
flowmeters, operators were unable to accurately
compensate for composition changes. By placing a
Coriolis flowmeter on the main feedstock line, operators
were able to recognize feedstock changes, allowing
them to reach their production targets and monitor
catalyst deactivation. A 2% increase in throughput
was worth $1 MM in the first year.
Tying everything together. An effective sustainabilitythrough-efficiency
project has many aspects; therefore, it requires
coordination to achieve the desired goals. Each element
can deliver gains on an individual basis, but when linked together
through a common master plan (FIG. 7), truly synergistic effects
can compound the benefits. Management should consider
this type of plan as a key to long-term improvements capable
of improving profits, reducing carbon footprint and making operations
more sustainable.
LITERATURE CITED
1
U.S. EIA, " EIA projects nearly 50% increase in world energy use by 2050, led by
growth in renewables, " October 7, 2021, online: https://www.eia.gov/todayinenergy/detail.php?id=49876
MARCELO
CARUGO works with upstream and downstream manufacturers
globally to create a clear and actionable path to operational excellence and
digital transformation through applications of automation technologies.
He joined Emerson in 1998 and has more than 30 yr of experience in the chemical
and refining process control industries, both domestically and internationally.
Mr. Carugo received an electronic engineering degree from the University of
Buenos Aires, Argentina; a post graduate diploma in electronic engineering
from PIITS in the Netherlands; and a Master of electronic engineering with
honors from NUFFIC in the Netherlands.

https://www.eia.gov/todayinenergy/detail.php?id=49876 https://www.eia.gov/todayinenergy/detail.php?id=49876 http://www.HydrocarbonProcessing.com

Hydrocarbon Processing - January 2022

Table of Contents for the Digital Edition of Hydrocarbon Processing - January 2022