Conceptual Design of a Natural Gas Processing Plant in Western Niger Delta Area

Abstract

Nigeria has approximately 200.4 trillion cubic feet (Tcf) of proved
natural gas reserves by the end of 2019, not much has been done to
increase its economic value. Nigeria has an abundant source of energy
in natural gas, which can drive and sustain development for a very
long period if these assets are effectively processed into the various
useful components. Availability of electrical power is a key component
in the development of a nation, Nigeria’s transformation from a
developing nation to a developed nation has largely been stalled by
epileptic power supply. This challenge can be resolved by providing
infrastructures to process and transform natural gas energy into
electrical energy. An indigenous E & P company wishes to undertake
the development of a 30MMscf/d natural gas processing plant. This
study was therefore initiated to design the gas plant that will process
the produced natural gas to meet the specification of a nearby electric
power generating plant which will utilized the processed natural gas
for electric power generation. A process simulator (ASPEN HYSIS)
was used to model the natural gas flow from the feed receiving section
down to the sales point to determine natural gas processing plant
requirements. Fluid samples were acquired and detailed PVT analysis
was carried out to determine the gas composition. Results of the
process simulation shows that, to process the 30MMScf/d flow of
natural gas, the natural gas plant will require five coolers, three
separators (One three phase separator, one two phase separator and
a stock tank), four compressors, a pump and a TEG dehydrating unit.
The outlet gas has a pressure of 690 psia, water content of 0.257 lbm
of H2O/ MMscf of gas, and gross heating value of 1219.72 btu/scf
which meets the customer’s requirement.