Brochure

Inlet Feed Gas Control Valve
The inlet receiving facilities serve a number of functions that
are critical to the smooth operation of the entire facility. The
receiving facilities knock out any liquids present in the feed
gas, reduce the pressure from the gas pipeline, and throttle
the ow of gas into the downstream processing units. Stable
and reliable operation of the receiving facilities lays the
foundation for the protable operation of the entire facility.
The location of the inlet feed gas valves will depend on the
extent of gas treatment located onsite. If the facility includes a
gas treatment unit and receives raw feed gas from production,
the inlet valve is located upstream of the acid gas removal
unit. If the liquefaction plant receives sales-quality gas from
the local grid, which requires minimal treatment, the valve will
be located upstream of the liquefaction trains.
At some facilities, a single large valve is used in this
application. At others, a number of smaller valves in parallel
will be used to control the ow of the feed gas. Reliability is the
foremost requirement for the inlet feed valves. Unexpected
maintenance or surprise failures have the potential to bring
down LNG production, which can incur signicant contractual
penalties. In addition, these valves must also be able to
provide precise, stable control through a wide range of gas
ow rates from startup and commissioning through full rated
output of the plant. These valves must operate with minimal
variability to ensure stable and predictable performance of
all process units downstream. Depending on the operating
pressure of the pipeline, these valves can also experience a
signicant pressure drop. This can cause the potential for
damaging noise and vibration if not addressed properly.
The operator of a multi-train
liquefaction facility in Australia
needed absolute assurance that
their critical feed gas inlet valves
would provide the proper rate of
flow into the facility. Too much
flow could overwhelm the plant’s
pressure relief capacity, requiring
expensive modifications. Too little flow could restrict the overall
capacity of the entire multi-billion dollar facility.
Emerson engineers developed custom Fisher Whisper Trim
designs for these NPS 12 ANSI 1500 valves tailored specifically to
the noise and capacity requirements of this critical application.
To provide the ultimate assurance that these custom valves
would meet the exacting application requirements, the
valves were flow tested at the Emerson Innovation Center to
demonstrate the maximum capacity.
Flow testing confirmed the actual capacity of the valves to be
within 3% of the design values, well within the plant operator’s
specification.
A Case-In-Point
8 | Fisher
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LNG Liquefaction Solutions