Oil and gas production handbook - Process Control and ...
Oil and gas production handbook - Process Control and ...
Oil and gas production handbook - Process Control and ...
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Large rotating equipment <strong>and</strong> the generators are driven by <strong>gas</strong> turbines or large<br />
drives. Gas turbines for oil <strong>and</strong> <strong>gas</strong> duty are generally modified aviation turbines in<br />
the 10-25 MW range. These require quite extensive maintenance <strong>and</strong> have a<br />
relatively low overall<br />
efficiency (20-27% depending<br />
on application). Also, while<br />
the turbine is relatively small<br />
<strong>and</strong> light, it will usually<br />
require large <strong>and</strong> heavy<br />
support equipment such as<br />
large gears, air coolers/filters,<br />
exhaust units, sound damping<br />
<strong>and</strong> lubrication units.<br />
Therefore use of large variable<br />
speed drives is becoming more<br />
common. For pumps on<br />
Subsea facilities this is the only option. For use on remote facilities, High Voltage<br />
DC transmission <strong>and</strong> HV motors can be used, from a main facility or power from<br />
shore. This will also avoid local power generation at each facility <strong>and</strong> contribute to<br />
low manning or remote operation.<br />
5.3 Flare <strong>and</strong> Atmospheric Ventilation<br />
The flare subsystem include Flare,<br />
atmospheric ventilation <strong>and</strong> blow down. The<br />
purpose of the Flare <strong>and</strong> Vent Systems is to<br />
provide safe discharge <strong>and</strong> disposal of <strong>gas</strong>es<br />
<strong>and</strong> liquids resulting from:<br />
• Spill-off flaring from the product<br />
stabilisation system. (<strong>Oil</strong>, Condensate<br />
etc.).<br />
• Production testing<br />
• Relief of excess pressure caused by<br />
process upset conditions <strong>and</strong> thermal<br />
expansion.<br />
• Depressurisation either in response to<br />
an emergency situation or as part of a<br />
normal procedure.<br />
• Planned depressurisation of subsea <strong>production</strong> flowlines <strong>and</strong> export<br />
pipelines.<br />
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