Chemical Engineering April 2021 - 5

Chementator
Thermal-energy storage system
can decarbonize industrial heat
A
closed-loop, long-duration energystorage
system (diagram) developed
by Malta, Inc. (Cambridge,
Mass.; www.maltainc.com) could
provide a carbon-neutral path to industrial
heating. " One of the exciting facets of this
technology is that it generates a lot of discharge
heat. When we charge our system
with renewable energy, the heat we're discharging
is, in effect, decarbonized, usable
heat, " says Ty Jagerson, vice president of
commercialization at Malta. Take, for example,
Malta's 100-MW M100 system, which is
designed for 10 h of charging and discharging
per day. " During the discharge cycle, the
system is generating 100 MW of electricity,
while also generating 70 MW of 100°C
heat - over 10 h, that's 700 MWh of usable
industrial heat, " notes Jagerson. Industrial
drying applications - for instance, drying
biosolids in wastewater-treatment applications
or residues from agricultural or pulpand-paper
processing - are particularly
well-suited to efficiently
utilize the
generated heat.
" In that 100°C
range, there's a
massive amount
of heat demand
that we could take
care of basically by
using leftover wind
and solar power, "
he adds.
Malta's thermal
storage system incorporates
a novel
Charge Mode
(heat pump)
Heat fl ow
Hot molten
salt tank
Charge
compressor
Heat exchanger
Motor (electricity in)
Heat exchanger
Heat fl ow
Warm molten
salt tank
Charge
turbine
Warm molten
salt tank
Discharge
compressor
Coolant
ambient tank
heat-exchanger design co-developed by
Alfa Laval AB (Lund, Sweden), one of Malta's
major investors. In charging (heat pump)
operation, renewable energy runs a charging
turbine, which sends hot air through a
compressor into a heat exchanger, transferring
the air's thermal energy to molten salt,
which is subsequently stored in a hot tank,
while the cooled media flows between a pair
of coolant tanks. When the energy stored in
the molten salt needs to be discharged, the
temperature difference between the system's
tanks is converted to thermal energy, and hot
air runs through a second turbine, sending
electricity back to the grid. " The system is
based on a closed-loop Brayton cycle. When
we're charging the system, the air flows in
one direction, and then we change the direction
of airflow when we are discharging, "
explains Jagerson. Current designs are focused
on 10-12 h of storage, but Malta is
seeing increased interest in storage durations
as high as 5-7 days.
Discharge Mode
(heat engine)
Heat fl ow
Heat exchanger
Motor (electricity out)
Heat exchanger
Heat fl ow
Hot molten
salt tank
Discharge
turbine
Edited by:
Gerald Ondrey
L-ALANINE
DMC Biotechnologies,
Inc. (DMC; Boulder,
Colo.; www.dmcbio.com)
has successfully demonstrated
full commercial
scale (85 m3) fermentation
for its first product, the
amino acid L-alanine. The
scaleup results identically
tracked the performance
at bench and pilot scales,
further validating the predictability
and scalability
of DMC's Dynamic Metabolic
Control technology,
the company says. Commercial
performance metrics
were demonstrated,
meaning that no further
strain improvements are
required to achieve the
target selling price.
This demonstration of
Coolant cold
tank
Coolant cold
tank
Coolant
Malta
Recycling electrolyte from vanadium RFBs
U
.S. Vanadium LLC (Hot Springs,
Ark.; www.usvanadium.com) has
successfully demonstrated the
ability to recycle the liquid electrolyte
used in vanadium redox-flow batteries
(VRFB), a rapidly growing commercial technology
that promises to enable intermittent
renewable energy technologies, such
as solar and wind, to provide power on a
continuous basis (see Redox Flow Batteries
Charge Forward, Chem. Eng. September
2016, pp. 14-20).
Against
a
background of
increasingly
prevalent waste-disposal issues faced by
lithium-ion batteries, VRFBs have the important
benefit of its liquid electrolyte being
nearly 100% recyclable. Vanadium electrolyte,
and its ability to be recycled for continuing
use, is considered to be a key advantage
for the technology that is expected to lead to
increased worldwide adoption of VRFBs as
an alternative to Li-ion batteries.
U.S. Vanadium recently demonstrated the
technical and economic feasibility of recycling
VRFB electrolyte provided by Invinity
Energy Systems plc (Vancouver, B.C., Canada;
). The VRFB electrolyte recycling initiative
at U.S. Vanadium, where a vanadium
recovery rate of 97% was achieved, was
led by Mike Woolery, vanadium technologist
for U.S. Vanadium. A description of the recycling
process and other recycling options
can be found at the company's website in a
March 8th blog post.
CHEMICAL ENGINEERING WWW.CHEMENGONLINE.COM
APRIL 2021
ambient tank
process robustness and
predictability across scale
of production - from
high-throughput screening
to full commercial
scale - has never been
demonstrated in the field
and represents a major advancement
for DMC. This
core technology enablement
will also be beneficial
for DMC's pipeline of products
that will be scaled and
commercialized next.
The scale-up process was
conducted at the Leuna
facility of EW Biotech
GmbH (Leuna, Germany;
www.ew-biotech.com).
UF MEMBRANE
Toray Industries,
Inc.
(Tokyo, Japan; www.
toray.com) has developed
a new polyvinylidene fluoride
(PVDF) ultrafiltration
(UF) membrane that has
an " exceptional "
virus
removal rate, as well as
a high water permeability,
making it suitable for
water purification.
The
company is accelerating
application testing, with
the aim to commercialize
the technology.
Toray improved its PVDF
(Continues on p. 6)
5
http://www.maltainc.com http://www.dmcbio.com http://www.ew-biotech.com http://www.usvanadium.com http://www.toray.com http://WWW.CHEMENGONLINE.COM
Chemical Engineering April 2021

Table of Contents for the Digital Edition of Chemical Engineering April 2021
