Page 284 - Hydrocarbon Exploration and Production Second Edition
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Surface Facilities 271
Feasibility Is it viable?
Definition How should it look?
Preliminary How can it be built?
Design What will it cost?
Detailed Prepare the assembly Increasing Costs
Design instructions
Procurement Get the bits
Construction Build it
Commissioning Make sure it works
Post Project Could we have
Review done it better?
Figure 11.4 Project phasing.
11.1.1.5. Describing hydrocarbon composition
Before oil and gas processing are described in detail in the following sections, it is
useful to consider how oil and gas volumes and compositions are reported.
A container full of hydrocarbons can be described in a number of ways, from a
simple measurement of the dimensions of the container to a detailed compositional
analysis. The most appropriate method is usually determined by what you want to
do with the hydrocarbons. If, for example, hydrocarbon products are stored in a
warehouse prior to sale, the dimensions of the container are very important, and the
hydrocarbon quality may be completely irrelevant for the store keeper. However, a
process engineer calculating yields of oil and gas from a reservoir oil sample will
require a detailed breakdown of hydrocarbon composition, that is what components
are present and in what quantities.
Compositional data are expressed in two main ways: components are shown as a
volume fraction or as weight fraction of the total (Figure 11.5).
The volume fraction would typically be used to represent the make up of a gas at
a particular stage in a process and describes gas composition, for example 70%
methane and 30% ethane (also known as mol fractions) at a particular temperature
