H2Tech - Q4 2021 - 29

GREEN HYDROGEN PRODUCTION
The challenges of delivering
a large-scale green H2
With a global energy transition underway,
interest in H2
as an essential
vector in a future energy system is skyrocketing.
Presently, 96% of global H2
production is gray or brown H2
produced
via reforming and/or gasification
of natural gas, oil and coal1
(FIG. 1), with
concomitant carbon emissions. For H2
to be part of the decarbonization drive,
carbon emissions from gray and brown
H2
produce blue H2
must be captured and sequestered to
. Alternatively, green H2
generation via water electrolysis using
renewable energy must be rapidly scaled
up and deployed.
In Q1 2021, Petrofac delivered a
front-end engineering design (FEED)
for the Arrowsmith Hydrogen Plant
(AHP), a staged development by Infinite
Blue Energy (IBE) Group, located
in Western Australia, that uses wind and
solar energy to produce green H2
1 of the project, a 25-metric-tpd H2
. Stage
production
facility, is designed with a roadmap
to scale up green H2
a capacity of 300 metric tpd by Stage 3.
Several challenges were encountered
that are not typically faced in the design
of gas processing facilities. With H2
on
the ascendency, and similar projects expected
to proliferate over the next few
years, this article will highlight these
design challenges and provide recommendations
for successfully dealing with
them. Some of the recommendations
apply to both blue and green H2
tion. Also, the deployment of green H2
producis
explored
to identify the critical factors
that will promote or hinder the proliferation
of this technology.
The challenges described here were
addressed in the initial design of Stage 1
of the H2
production facility. The design
offtake requirements.
has since evolved with regard to power
generation and H2
FIG. 2. Block flow diagram of H2
production process.
H2Tech | Q4 2021 29
FIG. 1. Global demand and sources of H2 production.1
production to
project-Part 1
C. BILIYOK, M. CZARNECKI and A. DAR, Petrofac, Woking, UK;
and S. J. GAULD, Infinity Blue Energy, Perth, Australia
Process description. AHP Stage 1 is designed
to produce 25 metric tpd of green
H2
from bore water using electrolysis and
renewable energy sourced from onsite renewable
power generation (FIG. 2).
Bore water is sourced from a local
aquifer and stored in a day tank. From the
tank, the water is pumped to a water treatment
package (WTP) to remove minerals
and salts to meet the demineralized
(DM) water specification for the electrolyzers.
About half of the flowrate of the
water into the WTP is discarded as reject
water. The demineralized water is routed
to a DM water tank with sufficient buffer
volume to feed the electrolyzers should
the WTP be temporarily unavailable.
The DM water is then pumped to the
electrolyzer unit to generate H2
and oxygen.
Several electrolyzers from different
vendors were considered at the concept
stage of this project, and the electrolyzer
selection narrowed to either an alkaline
electrolyzer or a polymer electrolyte
membrane (PEM) electrolyzer.
H2
gas produced from the electrolyzer
is first compressed to an appropriate pressure,
then conditioned to eliminate any
impurities, such as water vapor and oxygen
(depending on the type of electro
H2Tech - Q4 2021

Table of Contents for the Digital Edition of H2Tech - Q4 2021
