Hydrocarbon Processing - June 2022 - 71

Carbon Capture/
CO2
Mitigation
J. BUEHLER, Petrogenium, Buehler Consulting,
Houston, Texas
Overview of decarbonization pathways for the
oil and gas and petrochemical industries-Part 2
This article is the continuation of an
article detailing the seven pathways to
decarbonizing the oil and gas and petrochemical
industries. Part 1, published
in the May issue of Hydrocarbon Processing,
covered sustainability and reviewed
the following three pathways: green and
blue hydrogen (H2
); biofuels, renewable
fuels and e-fuels; and the circular carbon
cycle. This article will discuss the first
four pathways to decarbonizing the oil
and gas and petrochemical industries:
1. Energy efficiency/
stopping methane leakage
2. New technologies
3. Electrification
4. Carbon capture, utilization and
storage (CCUS) technology.
Additionally, as detailed in Part 1, renewable
power is also key to generating green
H2
by electrolysis.
Pathway 1: Energy efficiency/stopping
methane leakage. Improving
energy efficiency and stopping methane
leaks is the cheapest way to reduce
CO2
e emissions and CO2
plants do not burn or leak the fuel to atmosphere,
CO2
capture, after cone
is not produced and the
organization saves on the cost of the fuel
(i.e., a win-win situation).
Some energy projects will have a
negative cost of CO2
sidering the capital expenditure cost,
and the variable and operational costs.
Capital energy projects can have less
than a 2 yr-3 yr payback, while maintenance
projects can achieve payback in
just 2 mos-3 mos.
Conduct an energy and greenhouse
gas (GHG) study at your plant. Operators
should use their internal company
specialists, or an outside energy process
consultant, to obtain an independent
review of the facility for a fresh look toward
identifying any possible overlooked
energy/GHG reduction opportunities.
This study should be structured using
process unit-specific checklists, and
should identify opportunities, conduct
a high-level estimate of potential energy/GHG
savings, estimate the cost of
projects, and develop a prioritized list of
energy/GHG improvement opportunities.
Quick-win projects, along with projects
that could be accomplished during
the next turnaround, should be flagged
for early implementation. Savings from
quick-payback projects can be used to
fund additional energy projects.
An energy and GHG reduction study
should focus on the following items:
process optimization, equipment performance
and utility system optimization.
Process optimization. Process ope
intensity. If
timization includes the following focal
points:
* Distillation: Optimize
pumparounds, avoid over
refluxing, utilize advanced process
control to meet specifications
and minimize product giveaway,
and optimize column pressure
and feed temperature.
* Reactions: Optimize H2:oil
ratios and yield vs. energy vs. run
length, and catalyst selection.
* Heat recovery: Use pinch analysis
to identify opportunities to recover
process heat lost to air or cooling
water. Use a heat pump to upgrade
low-temperature waste heat to a
useable heat source-this process
can recover 2-3 times the energy
required by the heat pump.
Use an organic Rankine cycle
to convert waste heat to electricity.
* Stop methane leakage by
conducting surveys and fixing
leaks. The use of drones can
help with inspection work.
* Use online, real-time monitoring of
energy key performance indicators
(KPIs) available to operators.
Monetize the financial gap between
the current operation and the
previously demonstrated best
performance. Operators should
use advanced process control,
optimizers and digital twins.
* Stop continuous flaring, and revise
procedures to minimize flaring
during startups and shutdowns.
Equipment performance. The following
steps can be taken to enhance
equipment performance:
* Improve fired heater efficiency
by monitoring stack temperatures
and excess air, adjusting burners,
cleaning the convection section
and repairing air preheaters. A
2% oxygen reduction in stack
flue gas equals a 1% efficiency
improvement. A 20°C reduction
in stack temperature (with
reasonable excess air) equates to
a 1% efficiency improvement.
* Monitor vacuum improvements
on condensing turbines. An
improvement of 1.2 in. Hg (0.6 psia)
equates to a 5% improvement. On
a large 250,000-lb/hr condensing
turbine, a 5% improvement saves
more than $850,000/yr in fuel
cost (natural gas at $6/MMBtu,
boiler efficiency of 85%).
Hydrocarbon Processing | JUNE 2022 71

Hydrocarbon Processing - June 2022

Table of Contents for the Digital Edition of Hydrocarbon Processing - June 2022

Contents
Hydrocarbon Processing - June 2022 - Cover1
Hydrocarbon Processing - June 2022 - Cover2
Hydrocarbon Processing - June 2022 - Contents
Hydrocarbon Processing - June 2022 - 4
Hydrocarbon Processing - June 2022 - 5
Hydrocarbon Processing - June 2022 - 6
Hydrocarbon Processing - June 2022 - 7
Hydrocarbon Processing - June 2022 - 8
Hydrocarbon Processing - June 2022 - 9
Hydrocarbon Processing - June 2022 - 10
Hydrocarbon Processing - June 2022 - 11
Hydrocarbon Processing - June 2022 - 11A
Hydrocarbon Processing - June 2022 - 11B
Hydrocarbon Processing - June 2022 - 12
Hydrocarbon Processing - June 2022 - 13
Hydrocarbon Processing - June 2022 - 14
Hydrocarbon Processing - June 2022 - 15
Hydrocarbon Processing - June 2022 - 16
Hydrocarbon Processing - June 2022 - 17
Hydrocarbon Processing - June 2022 - 18
Hydrocarbon Processing - June 2022 - 19
Hydrocarbon Processing - June 2022 - 20
Hydrocarbon Processing - June 2022 - 21
Hydrocarbon Processing - June 2022 - 22
Hydrocarbon Processing - June 2022 - 23
Hydrocarbon Processing - June 2022 - 24
Hydrocarbon Processing - June 2022 - 25
Hydrocarbon Processing - June 2022 - 26
Hydrocarbon Processing - June 2022 - 27
Hydrocarbon Processing - June 2022 - 28
Hydrocarbon Processing - June 2022 - 29
Hydrocarbon Processing - June 2022 - 30
Hydrocarbon Processing - June 2022 - 31
Hydrocarbon Processing - June 2022 - 32
Hydrocarbon Processing - June 2022 - 33
Hydrocarbon Processing - June 2022 - 34
Hydrocarbon Processing - June 2022 - 35
Hydrocarbon Processing - June 2022 - 36
Hydrocarbon Processing - June 2022 - 37
Hydrocarbon Processing - June 2022 - 38
Hydrocarbon Processing - June 2022 - 39
Hydrocarbon Processing - June 2022 - 40
Hydrocarbon Processing - June 2022 - 41
Hydrocarbon Processing - June 2022 - 42
Hydrocarbon Processing - June 2022 - 43
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Hydrocarbon Processing - June 2022 - 50
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Hydrocarbon Processing - June 2022 - 62
Hydrocarbon Processing - June 2022 - 63
Hydrocarbon Processing - June 2022 - 64
Hydrocarbon Processing - June 2022 - 65
Hydrocarbon Processing - June 2022 - 66
Hydrocarbon Processing - June 2022 - 67
Hydrocarbon Processing - June 2022 - 68
Hydrocarbon Processing - June 2022 - 69
Hydrocarbon Processing - June 2022 - 70
Hydrocarbon Processing - June 2022 - 71
Hydrocarbon Processing - June 2022 - 72
Hydrocarbon Processing - June 2022 - 73
Hydrocarbon Processing - June 2022 - 74
Hydrocarbon Processing - June 2022 - 75
Hydrocarbon Processing - June 2022 - 76
Hydrocarbon Processing - June 2022 - 77
Hydrocarbon Processing - June 2022 - 78
Hydrocarbon Processing - June 2022 - 79
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Hydrocarbon Processing - June 2022 - 83
Hydrocarbon Processing - June 2022 - 84
Hydrocarbon Processing - June 2022 - 85
Hydrocarbon Processing - June 2022 - 86
Hydrocarbon Processing - June 2022 - 87
Hydrocarbon Processing - June 2022 - 88
Hydrocarbon Processing - June 2022 - 89
Hydrocarbon Processing - June 2022 - 90
Hydrocarbon Processing - June 2022 - Cover3
Hydrocarbon Processing - June 2022 - Cover4
Hydrocarbon Processing - June 2022 - GP-1
Hydrocarbon Processing - June 2022 - GP-2
Hydrocarbon Processing - June 2022 - GP-3
Hydrocarbon Processing - June 2022 - GP-4
Hydrocarbon Processing - June 2022 - GP-5
Hydrocarbon Processing - June 2022 - GP-6
Hydrocarbon Processing - June 2022 - GP-7
Hydrocarbon Processing - June 2022 - GP-8
Hydrocarbon Processing - June 2022 - GP-9
Hydrocarbon Processing - June 2022 - GP-10
Hydrocarbon Processing - June 2022 - GP-11
Hydrocarbon Processing - June 2022 - GP-12
Hydrocarbon Processing - June 2022 - GP-13
Hydrocarbon Processing - June 2022 - GP-14
Hydrocarbon Processing - June 2022 - GP-15
Hydrocarbon Processing - June 2022 - GP-16
Hydrocarbon Processing - June 2022 - GP-17
Hydrocarbon Processing - June 2022 - GP-18
Hydrocarbon Processing - June 2022 - GP-19
Hydrocarbon Processing - June 2022 - GP-20
Hydrocarbon Processing - June 2022 - GP-21
Hydrocarbon Processing - June 2022 - GP-22
Hydrocarbon Processing - June 2022 - GP-23
Hydrocarbon Processing - June 2022 - GP-24
Hydrocarbon Processing - June 2022 - GP-25
Hydrocarbon Processing - June 2022 - GP-26
Hydrocarbon Processing - June 2022 - GP-27
Hydrocarbon Processing - June 2022 - GP-28
Hydrocarbon Processing - June 2022 - GP-29
Hydrocarbon Processing - June 2022 - GP-30
Hydrocarbon Processing - June 2022 - GP-31
Hydrocarbon Processing - June 2022 - GP-32
Hydrocarbon Processing - June 2022 - GP-33
Hydrocarbon Processing - June 2022 - GP-34
Hydrocarbon Processing - June 2022 - GP-35
Hydrocarbon Processing - June 2022 - GP-36
Hydrocarbon Processing - June 2022 - GP-37
Hydrocarbon Processing - June 2022 - GP-38
Hydrocarbon Processing - June 2022 - GP-39
Hydrocarbon Processing - June 2022 - GP-40
Hydrocarbon Processing - June 2022 - GP-41
Hydrocarbon Processing - June 2022 - GP-42
Hydrocarbon Processing - June 2022 - GP-43
Hydrocarbon Processing - June 2022 - GP-44
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https://www.nxtbook.com/nxtbooks/gulfpub/petrochemical_2018_v2
https://www.nxtbook.com/nxtbooks/gulfpub/petrochemical_2018
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201812
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