Advances in Chemical Engineering and Science, 2020, 10, 297-321
https://www.scirp.org/journal/aces
ISSN Online: 2160-0406
ISSN Print: 2160-0392
DOI: 10.4236/aces.2020.104019 Sep. 4, 2020 297 Advances in Chemical Engineering and Science
Gas Flare Design Debottlenecking
Using Pinch Analysis
Lawrence Leelabari Pemii, Kenneth Kekpugile Dagde, ThankGod Oweifa Goodhead
Department of Chemical/Petrochemical Engineering, Rivers State University, Nkpolu-Oroworukwo, Nigeria
Abstract
Gas flaring is concerned with the combustion of lighter ends of hydrocarbon
mostly produced in association with crude oil. Flare networks are designed to
handle the gas volume required to be flared. Most times, this flare networks
are in close proximity but still have independent flare stacks, increasing risk
to environment and cost on infrastructures. There is a need to integrate the
flare networks in facilities within same area and through the application of
Pinch Analysis concept, the resultant flare network can be optimized to give a
system having optimal tail and header pipe sizes that will reduce cost and
impact on environment. In the light of the foregoing, the concept of pinch
analysis was used in debottlenecking integrated gas flare networks from a flow
station and a refinery in close proximity. Both flare networks were integrated
and the resultant gas flare network was optimized to obtain the optimum pipe
header and tail pipe sizes with the capacity to withstand the inventory from
both facilities and satisfy the set constraints such as Mach number, noise,
RhoV
2
and backpressure. Mach number was set at 0.7 for tail pipes and 0.5
for header pipes, noise limit was not to exceed 80 dB upstream and 115 dB
downstream the sources, RhoV
2
was limited to 6000 kg/m/s
2
and the back
pressure requirement was source dependent respectively. The fire case scenario
was considered, as it is the worst-case scenario in the studies. When pinch
analysis was applied in debottlenecking the combined gas flare network, it
gave smaller tail and header pipe sizes which is more economical. A 20%
decrease in pipe sizes was recorded at the end of the study.
Keywords
Gas Flaring, Pinch Analysis, Debottlenecking, Aspen FlareNet, Optimization,
Header Pipe, Tail Pipe
1. Introduction
Gas flaring has to do with the combustion of associated, unwanted or excess
How to cite this paper: Pemii, L.L., Dagde,
K.K. and Goodhead, T.O. (2020) Gas Flare
Design Debottlenecking Using Pinch Analy-
sis. Advances in Chemical Engineering and
Science, 10, 297-321.
https://doi.org/10.4236/aces.2020.104019
Received: May 30, 2020
Accepted: September 1, 2020
Published: September 4, 2020
Copyright © 2020 by author(s) and
Scientific Research Publishing Inc.
This work is licensed under the Creative
Commons Attribution International
License (CC BY 4.0).
http://creativecommons.org/licenses/by/4.0/
Open Access