June
2016
27
HYDROCARBON
ENGINEERING
T
he flare system is the ‘last line of defence’ that
prevents hydrocarbon pollutants from entering
the atmosphere; therefore, it is one of the most
important systems in a refinery or chemical plant,
as it needs to be running in parallel with the facility while it
is in operation. If the flare was unavailable or under
maintenance, the entire plant would be shut down, leading
to significant revenue losses for the owners of the facility.
An improperly designed flare system could lead to serious
accidents, resulting in significant plant damage, loss of
human life and damage to the environment. Therefore, the
proper design and operation of a flare
system is of the utmost importance. Some of the factors
that need to be reviewed when designing a reliable flare
system are described in this article.
Selecting an appropriate flare header
configuration
The simplest flare system configuration has a single flare
header connected to a single flare knockout drum, which is
routed to an elevated flare stack. The flare header(s) needs
to be sized with consideration to the maximum permissible
Mach number and back pressure criteria permitted by the
flare design regulations being followed. There are
Gardens of Versailles, France.
