Hydrocarbon Processing - October 2021 - 42
Plant Safety and Environment
preheat system required the following modifications and
cross-checking:
* New burners suitable for forced-draft conditions
* New air preheater with ductwork-adequate plot
space is required for such heat recovery systems
* New forced-draft fans and induceddraft
fan must be installed
* Dampers and other blinding provisions required
* New control philosophy and complex
control loop of the air preheat circuit.
Mission accomplished: Summarizing the study. With a
primary focus on reducing carbon emissions from the furnace,
the operating parameters and hardware change strategies were
put to work. Results presented a strong sense of optimism with
CO2
50
100
150
200
250
300
Baseline-
original
condition
Step 1:
Excess air
optimization
Step 2:
Adding
APH
FIG. 1. Stepwise reduction in carbon footprint.
Step 3:
Converting
to fuel gas
Step 4:
Finetuning
the parameters
Environmental pledge. Our planet has seen radical changes
since the industrial revolution. Fossil fuels have dramatically improved
the global quality of life; however, the positives are accompanied
by an associated battery of negatives, the worst being
industry's effects on the environment. With significant releases
of GHGs, the planet's natural cycles have been altered (e.g.,
the depletion of polar permafrost, rising sea levels and increasingly
frequent coastal storms, tornados, forest fires, floods and
droughts). An organized, concerted effort is imperative throughout
the entire value chain to reduce GHG emissions.
As detailed in this article, well-established solutions-efficiency
improvements, waste heat integration, fuel substitution
and H2
-rich fuel firing-were applied on a common refinery
fired heater or furnace. The results are encouraging: significant
carbon emissions can be reduced by existing, proven techniques
that will pave the way for further advanced technologies.
LITERATURE CITED
1 Ferguson, S. and M. Stockle, " Carbon capture options for refiners, " PTQ, 2Q 2012.
2 Creek, T., " Role of carbon capture in CO2
management, " PTQ, 2Q 2004.
3
Listen to
Hydrocarbon Processing's
podcast for the latest
technologies in the
downstream industry.
4
Mukherjee, R. and S. Singh, " Evaluating hydrogen-rich fuel gas firing, " PTQ,
1Q 2021.
Mukherjee, R. and S. Singh, " Savings through subtle operational adjustments, "
Hydrocarbon Engineering, April 2021.
SHILPA SINGH is General Manager in Engineers India Ltd.'s Heat
Transfer department, where she leads a team of chemical
engineers involved in grassroot designs, revamp studies, and
capacity and efficiency improvement projects for fired heater
systems. She holds a B.Tech degree in chemical engineering from
I.I.T. Delhi and has more than 24 yr of experience in this field.
The author can be reached at shilpa@eil.co.in.
SUBSCRIBE NOW!
HydrocarbonProcessing.com/Podcasts
RUPAM MUKHERJEE is Senior Manager in Engineers India
Ltd.'s Heat Transfer department. He has more than 13 yr of
experience in the design, engineering and troubleshooting of
fired heater systems. He holds a B.Tech degree in chemical
engineering from N.I.T. Durgapur and an M.Tech degree in
energy and environmental management from I.I.T. Delhi.
Author can be reached at rupam.mukherjee@eil.co.in
42 OCTOBER 2021 | HydrocarbonProcessing.com
242
234
204
144
140
emissions in tpd
carbon emissions being reduced from 242 metric tpd to 140
metric tpd, which is a reduction of almost 43%. Refer to FIG. 1 for
the stepwise reduction in carbon footprint of the furnace.
Another positive and promising result is visible in the appreciable
reduction in fuel consumption. Fossil fuels are depleting
quickly and are costly sources of energy. A savings of the
magnitude realized in this case study will result in significant
monetary savings.
The examination of the case study furnace establishes, once
again, the cardinal rule of carbon emissions reduction: enhancing
operating efficiency. Although all furnace geometries are
unique, some commonalities are applicable.
The study executed here also upholds that strategic decisions
aimed at reducing the carbon footprint of a 23-MMKcal/hr furnace
can curb CO2
levels by approximately 100 metric tpd. Considering
an average of 333 operating d/yr accounts for a carbon
footprint reduction of 33,300 metric tpy. Considering carbon
pricing-a common and well-debated buzzword-and assuming
an average carbon price of $20/t of CO2
, the revenue equivalent
of more than $6 MM/yr is generated. This alone outweighs
the cost of an air preheat system, even in cases where the applicability
of the air preheat system is not commercially justifiable by
fuel savings, such as for small-duty furnaces.
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Hydrocarbon Processing - October 2021
Table of Contents for the Digital Edition of Hydrocarbon Processing - October 2021
Contents
Hydrocarbon Processing - October 2021 - Cover1
Hydrocarbon Processing - October 2021 - Cover2
Hydrocarbon Processing - October 2021 - Contents
Hydrocarbon Processing - October 2021 - 4
Hydrocarbon Processing - October 2021 - 5
Hydrocarbon Processing - October 2021 - 6
Hydrocarbon Processing - October 2021 - 7
Hydrocarbon Processing - October 2021 - 8
Hydrocarbon Processing - October 2021 - 9
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Hydrocarbon Processing - October 2021 - Cover3
Hydrocarbon Processing - October 2021 - Cover4
Hydrocarbon Processing - October 2021 - GP-1
Hydrocarbon Processing - October 2021 - GP-2
Hydrocarbon Processing - October 2021 - GP-3
Hydrocarbon Processing - October 2021 - GP-4
Hydrocarbon Processing - October 2021 - GP-5
Hydrocarbon Processing - October 2021 - GP-6
Hydrocarbon Processing - October 2021 - GP-7
Hydrocarbon Processing - October 2021 - GP-8
Hydrocarbon Processing - October 2021 - GP-9
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Hydrocarbon Processing - October 2021 - GP-23
Hydrocarbon Processing - October 2021 - GP-24
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Hydrocarbon Processing - October 2021 - GP-36
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Hydrocarbon Processing - October 2021 - GP-39
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Hydrocarbon Processing - October 2021 - GP-41
Hydrocarbon Processing - October 2021 - GP-42
Hydrocarbon Processing - October 2021 - GP-43
Hydrocarbon Processing - October 2021 - GP-44
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