الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 117 |  |  |
| | | from | 117 | | |
Abstract
Nowadays, gas processing for NGLs (natural gas liquids) and LPG (liquefied
petroleum gas) recovery is becoming of great interest due to the increase in market
demand as well as the higher sale prices of these products. However, many of the
present NGL and LPG recovery units in operation don’t give the desired revenue.
This study focuses on the retrofitting of El-Wastani petroleum company (WASCO)
which is one of the most important NGL/LPG recovery units constructed in Egypt.
WASCO applied two cryogenic techniques to can recover LPG; process gas can
primary cooled to recover pentane plus (C5+) by mechanical refrigeration unit which
is based on pure propane as a refrigerant, finally the process gas is further cooled to
can recover LPG by expanding the gas.
The objective of this work is to retrofit El-Wastani LPG plant for improving NGL
recovery, hence a comparison had been hold between the most applicable cryogenic
techniques -in which WASCO plant could be retrofitted to- which can achieve the
same targeted cooling and recovery in terms of power consumption and required
additional capital cost to detect the best techniques to be applied to recover NGL
liquid. The most applicable cryogenic techniques were upgrading mechanical
refrigeration package, Upgrading Turbo Expansion (TE) package and replacing
propane refrigerant by mixed refrigerant.
Retrofit the existing plant by upgrading mechanical refrigeration unit will require the
highest capital investment among the provided approaches for NGL recovery.
Retrofit the existing plant by upgrading Turbo-expansion unit will require the highest
operating cost among the provided approaches for NGL recovery.
Replacing the pure propane refrigerant by the mixed refrigerant type was selected as
the best techniques which can applied to improve NGL recovery, due to its proper
physical and thermodynamic properties that lower exergy losses and raise the
exchanger effectiveness.
Another comparison had been hold to detect which degree of recovery (butane or
propane) will be selected to retrofit El-Wastani plant to it based on the highest ROI.
And found that retrofitting the existing plant to recover up to 95% of butane can
achieve the highest ROI (400 %) and lowest Pay-Back period (3 months), meanwhile
retrofitting the existing plant to recover up to 93% of propane can raise productivity
and profitability more than LPG recovery mode but with lower ROI (128.15 %) and
higher Pay-Back period (9.36 months).
The created simulation models could be used to model other LPG or NGL plants and
they could be used in monitoring and evaluating the performance and
productivity of the existing LPG plant and the new retrofitted plant. Also the study
can be used in conceptual engineering and in contractor/ licensor evaluations.
Hence, we recommend getting advantage of this work for further study to
increase the productivity and profitability of the existing LPG plant or any other
units recover NGL, to enhance the feed stock to the petrochemical industries.