Page 79 - Industrial plants

thermodynamic behavior of CO mixtures and in
2
particular the decompression curves in case of pipeline
ruptures (for those cases not fully covered by the
current state of art). The work done on
CO was focused mostly on predictive
2 Saipem is part of
models for CO with impurities with the
2 EPRG (European
objective to guarantee operating flexibility Pipeline Research
and safety. In fact impurities may cause Group) where the
side reactions, modify the extension of Hydrogen
the two phase region and have an effect Topic group is
Picture 8 – Saipem Pipe Laying Vessel Castorone increasing the saturation pressure which working at an
is the driving force in the running shear important test
guideline but also performing an important test fracture of a pipeline transporting liquid / campaign in H2
campaign in hydrogen environment to support the supercritical CO .
2 environment
guideline contents. The R&D gap analysis on the running
In parallel Saipem is conducting, in RINA-CSM ductile fracture for subsea lines
laboratories in Rome and Cosenza, an experimental transporting CO mixtures has led to the
2
test campaign to qualify a typical material for long and development of an internal guideline to design new or
high-pressure pipelines and the girth welds performed to verify repurposed lines and to identify that it would be
onboard Saipem Vessels. New tests are also planned in desirable to reinforce some assumptions with
2023 for coating and field joint coatings applied to experimental burst tests for medium diameters subsea
offshore pipelines. lines possibly in a new JIP on this specific subject.
Saipem is part of EPRG (European Pipeline Research
Group) where the Hydrogen Topic group is working at
an important test campaign in H environment. Safety Aspects and Loss
2
ASME B31.12, currently the main reference code on Prevention
Hydrogen piping and pipelines, could be complemented
and modified with additional considerations on material Safety aspects of Hydrogen, H /NG and CO pipelines
2 2
and welding properties in gaseous hydrogen are of paramount importance. The Major Accidental
environment and for offshore pipeline design. In this Hazards associated to H /NG and CO offshore pipeline
2 2
regard, Saipem is represented in ASME Europe systems are related to loss of containment events.
International Working Group B31.12 and will work In case of a subsea release from an offshore CO
2
together with the other members to complement the pipeline system, an underwater plume is produced
code as required by the new energy transport scenarios. which can impact the local flora and fauna due to pH
changing close to plume. If the plume reaches the sea
surface, it produces a bubble zone which can affect
CO Pipelines Offshore passing ships impacting on their buoyancy. Through
2
the bubble zone, the CO gas disperses in atmosphere
2
For submarine pipelines, the effort by Saipem is producing a cloud of asphyxiant/ toxic gas: pure CO is
2
focused on the understanding of the thermodynamic an asphyxiant gas and the content of impurities from
behavior of CO streams with impurities, the related CCS process, such as H S, CO , can increase its
2 2 2
flow assurance issues (phase control), the running toxicity. The cloud of asphyxiant/toxic gas can affect
ductile fracture phenomena, the readiness of in-line people on board of passing ships, or in the offshore
equipment and the safety aspects relevant to the installations or at shore causing injury from minor to
development of a risk assessment methodology for severe and potentially loss of life depending on toxic
CO Leakages. substances concentration and exposure time.
2
The DNV-RP-F104 for CO pipelines is already aligned In case of a subsea release from a hydrogen or H /NG
2 2
with the failure modes approach and advanced in terms pipeline, an underwater plume is produced as well. The
of specific requirements such as dealing with impurities. impact for underwater environment is less severe than
It has also a tested approach for specific failures mode CO case while the atmospheric dispersion can
2
such as the running ductile fracture in the 2021 edition produce an environmental impact from moderate to
with the contribution of the CO2SafeArrest Joint high or very high depending on the inventory released.
industry project. In addition, since Hydrogen is a flammable gas, easy to
The effort by Saipem is focused on the areas relevant ignite, the likelihood of a flash fire or explosion is higher
to offshore application still requiring further advancement than for natural gas case. The thermal effects of a flash
such as the validation of tools for calculating the fire due to hydrogen ignition as well as overpressure

IndustrIal Plants - May 2023
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