Resource constraints and the need for new economic paradigms

Energy Evolution Journal: Musings About an Ecologically Sane Human Society

My books about energy and economics

Contact: rogerkb at energyevolutionjournal dot com

Article_6

Capturing CO2 from lime production as solid sodium carbonate

10/12/2024

Calcium oxide, CaO and calcium hydroxide
[Ca(OH2)] are very useful compounds     
known respectively as quick lime and    
slaked lime. Slaked lime can be formed  
by reacting CaO with water. The calcium 
for these compounds comes from the      
abundant mineral limestone which has the
chemical formula CaCO3. When CaCO3 is   
heated to high temperature in a lime    
kiln carbon dioxide gas is driven off   
and CaO is left behind.                 
Various forms of lime are used in       
agricultural, environmental,            
metallurgical, construction,            
chemical/industrial applications, and   
more. According the National Lime       
Association[1] the single largest use   
lime is as a flux for purifying steel.  
Even if the energy for lime production  
came from carbon free sources the       
release of carbon from from limestone is
unavoidable. Therefore zero carbon lime 
production from limestone will require  
carbon capture and storage (CCS) for as 
long as humanity continues to utilize   
CaCO3 as a source material for this     
product. Capturing CO2 from traditional 
lime kilns is economically difficult so 
that various new methods of producing   
lime are a subject of research and      
development efforts[2].                 
One of these proposed new methods       
captures CO2 as part of the stable solid
compounds sodium carbonate (Na2CO3) and 
its hydrate Na2CO3.H2O. Sodium carbonate
and its hydrates are also known as      
washing soda.                           
The chemical reaction which produces    
slaked lime and sodium carbonate from   
calcium carbonate (limestone) and sodium
hydroxide (NaOH) is:                    

CaCO3 + NaOH + xH2O ==> Ca(OH)2 + Na2CO3.xH2O, x=(0,1)

This reaction is fast process which     
requires very little mixing energy. It  
avoids the need for high temperatures   
and therefore the need for fuel burning.
Since sodium carbonate is a stable solid
compound there is no need for pumping   
CO2 into underground reservoirs.        
However new energy and product disposal 
issues are introduced by the need to    
produce NaOH. This compound is typically
produced by the chlor-alkali process    
which produces NaOH and chlorine gas    
from salt (NaCl):                       

2NaCl + 2H2O ==> Cl2 + H2 + 2NaOH

This is an electrolytic process which   
requires a large input energy in the    
form of electrical current. Conceivably 
the electricity could come from carbon  
free renewable resources, but the cost  
of the electrolyzers and of the         
renewable electricity becomes part of   
the economic equation.                  
For each mole of NaOH produced 1/2 mole 
of Cl2 is produced. Since chlorine gas  
can not simply be released into the     
environment some use must be found for  
it. So the question arises of how much  
extra chlorine production would result  
from converting global lime production  
to this new method.                     
global lime 2024: 475MMT[3]             
global chlorine: 90MMT[4]               
CaO molecular weight is 56.1. Therefore 
the MMT moles of Cl2 produced would be: 
0.5*475/56.1 = 4.24                     
Cl2 molecular weight is 70.9. Therefore 
the MMT moles of Cl2 currently produced 
is 90/70.9 = 1.27                       
Therefore producing lime by the new     
method would require increasing the     
global production of Cl2 by a factor    
4.3. Since chlorine gas cannot simply be
released into the environment this      
excess production represents a          
significant barrier to using this method
of lime CCS at a large scale.           

[1] https://www.lime.org/

[2] https://www.sciencedirect.com/science/article/pii/S1364032122006505#bbib45

[3] https://www.expertmarketresearch.com/reports/lime-market

[4] https://www.researchandmarkets.com/reports/5305192/global-chlorine-industry-outlook-to-2025

Article_5 

Limitation of storing CO2 as baking soda

08/26/2024 
A paper on carbon capture in the    
form of bicarbonate ions (HCO3-)     
published 2023 prompted a flurry of 
headlines about storing captured    
carbon in the oceans as baking soda 
as the following to examples show.  
From newscientist.com:              
We can suck CO2 from the air and    
store it in the ocean as baking     
soda[2]                             
From theweek.com:                   
New carbon capture technology can   
turn carbon into baking soda[3]     
The idea is that hydroxide compounds
(a combination of positive ions with
negative OH- ions) in an aqueous    
solution can interact with CO2 to   
form to form bicarbonate compounds. 
For example:                        

Ca(OH)2 + 2CO2 ==> Ca(HCO3)2

The HCO3- ion is the carbonate ion  
and the combination of Ca2+ with    
this ion is calcium bicarbonate     
Ca(HC03)2.                          
Bicarbonate compounds are a source  
of alkalinity which can be released 
into the ocean which thus become a  
store of carbon without the         
acidification which comes from      
dissolved CO2.                      
In the paper referenced above they  
do not use Ca or any other common   
metal ion for carbon capture.       
Instead they use an engineered      
chemical complex called             
polyamine-Cu(II) complex,           
Polyam-N-Cu2+. Explaining the       
nature of this chemical complex     
is above my pay grade as a chemist  
so I will just refer to it at the   
mystery complex M2+. This complex   
can absorb CO2 just like Ca:        

M(OH)2 + 2CO2 ==> M(HCO3)2

This chemical reaction is reversible
so that applying heat will liberate 
the CO2 and restore the M(OH)2. The 
total energy and the temperature    
required to liberate the CO2 are    
much less than for capture systems  
which store carbon in the form of   
carbonates (e.g. CaCO3). Therefore  
this system could be used for       
traditional carbon capture and      
storage (CCS). That is you could    
blow air by your vats or trays of   
aqueous M(OH)2 until the solution   
was relatively saturated with CO2.  
After which the solution could be   
heated (possibly using waste heat)  
and a relatively dense stream of    
CO2 would be given off which could  
be captured and injected            
underground.                        
The authors however present another 
possibility for transforming        
M(HCO3)2 back into M(OH)2. They     
propose running a stream of sea     
water contain NaCl (ordinary table  
salt) through the carbon capture    
solution and using a water          
electrolyzer to split H2O. These    
actions result in the following net 
reaction:                           

M(HCO3)2 = 2NaCl + 2H2O ==> M(OH)2 + 2Na(HCO3) +2HCl

The M(OH)2 has been restored and in 
addition for each mole of M(OH2)2   
2 moles of sodium bicarbonate       
(baking soda) plus 2 moles of HCl   
(hydrochloric acid) have been       
produced. The sodium bicarbonate can
be released into the ocean as a     
beneficial source of alkalinity.    
However, dumping the hydrochloric   
acid into the ocean is not a cool   
thing to do, so the proposal is to  
sell HCl which is in demand for     
various industrial purposes. The    
money obtained from these sales     
helps to offset the cost operating  
the electrolyzers that are required 
for this method of CO2 storage. How 
extensively this method of carbon   
storage could be used would depend  
on how much demand there is for HCl.

[1]bicarbonate ions for the storage of captured carbon

[2]New Scientist on bicarbonate carbon storage

[3]The Week on bicarbonate carbon storage

Article_4

The continued use of lime obtained from limestone requires carbon capture and storage to acheive net zero cabon emissions

06/10/2024

Quick lime or calcium oxide (CaO)
is used for a variety of
industrial purposes. Typically it
is hydrated (CaO + H2O ==>
Ca(OH)2) prior to use. Among the
uses of this compound are:

1. Construction: lime is a key
ingredient cement, plaster, and
mortar

2. Steel Industry: lime is used
in the extraction of iron from
its ore and in removing
impurities from steel

3. Glass industry: lime is added
to soda-lime glass which is the
most common type (90% of
production).

4. Agriculture: lime is added to
acidic soil to correct its pH.

5. Water treatment: lime is added
to waste water to neutralize its
acidity

6. Chemical Synthesis: Calcium
Oxide serves as a cheap and
durable base for the synthesis of
numerous organic compounds.

The cheapest way to obtain CaO is
to heat limestone (CaCO3)
resulting in thermal
decomposition:

CaO3 + heat ==> CaO + CO2.

The heat could be provided by
carbon free renewable energy
sources, but the only way get to
net zero emissions for the carbon
released from the limestone is
via carbon capture and storage
(CCS).

For a number of manufacturing
processes (e.g. glass and steel)
the carbon emissions caused by
production of lime are a
relatively small fraction of the
total emissions. If you are into
the "more sustainable" meme you
might choose not to worry about
these emissions. After all if you
eliminate over 90% of CO2
emissions who but a killjoy would
spend a lot of time agonizing
over the remainder?

The British glass industry has
published a roadmap for reducing
carbon emissions[1], and to their
credit their goal is not to make
their industry "more
sustainable". Their goal is to
achieve net zero carbon emissions
by 2050. They are counting on CCS
to achieve 7% of emissions
reductions.

This use of CCS must continue for
perpetuity. As long as humanity
is using limestone as a source of
CaO we must continue to practice
CCS if we want net zero carbon
emissions.

The earth is very big place and
there may be lots of suitable
geologic sites for CCS. On the
other hand the earth's atmosphere
and oceans are very large
reservoirs of matter and for a
long time we assumed that human
emissions into these reservoirs
would have insignificant effects.
I hope we do not get surprised in
the matter of CCS. Lower total
resource demand through lower per
capita standards of consumption,
emphasis on long lived products,
and a high degree of recycling
would seem to be in order if we
are hoping for a long run of
human civilization on this
planet.

British Glass Net Zero Roadmap

Article_3

Falling particle reciever for concentrated solar power plants could potentially provide higher temperature and lower storage costs

05/17/2024

Recently (Jan 2024) a group of
Italian reasearcher published an
open access paper called "A
falling particle receiver thermal
model for system-level analysis
of solar tower plants". The
following three paragraphs are
taken from the introduction of
this paper:

"In the "Gen3 Roadmap" published
in 2017 by Sandia National
Laboratories (SNL), Mehos et al.
introduced the three most
interesting Solar Tower (ST)
technology pathways on which the
research effort should be focused
on (i.e., molten salts, falling
particle, gas phase). Following
an extensive analysis of those
three technologies carried out in
the frame of the Generation 3 CSP
Systems funding program, the U.S.
Department of Energy announced in
2021 that the most promising
pathway to achieve higher
temperatures in CSP plants and to
meet 2030 cost targets is the
one based on Particle Receiver
(PR).

In detail, the concept is to
adopt particles as a heat
transfer medium (HTM) instead of
liquid fluids; this leads to some
advantages including: i) the
possibility of HTM direct heating
that allows achievement of high
temperatures, and ii) the
possibility of cheaper Thermal
Energy Storage (TES) because heat
can be stored in a relatively
inexpensive medium (e.g. sand).

More precisely, the adoption of
direct heating allows avoiding
the exposure of metallic tubes to
the direct solar radiation
allowing achievement of high
temperatures and this leads in
turn to the possibility of
adopting power cycles with higher
efficiencies than the ones
adopted for conventional molten
salts receivers."

The high temperature power cycle
which I have seen mention most
often in connection concentrated
solar energy is a closed loop
Brayton cycle with carbon dioxide
as the working fluid. The typical
maximum temperature cited for a
practical implementation is in
the range of 700°C to
800°C. In the paper reference
above the particle outlet
temperature of the modeled solar
field is 750°C which sits in
the middle of the range targeted
by the Brayton cycle researchers.
The max temperature of existing
molten salt receivers is
600°C.

Article_2

Rheinmetall receives new orders for heat pumps for large commercial EVs

05/06/2024

Green Car Congress recently
posted an article[1] about some
large commercal orders for
Rheinmetall's heat pump module
designed to work in large
commercial electrified vehicles

From Rheinmetall's web site[2]:

"These two new orders mark the
next milestone in the Group's
marketing and positioning
strategy following the market
launch of the heat pump module,
which was specifically designed
for the electrification of drive
systems in commercial vehicles,
construction machinery, and
boats. The intelligent cooling
and heating management of the
heat pump pre-filled with R1234yf
not only increases the range of
vehicles and battery service life
but also makes driving more
comfortable. "


These heat pumps are an
interesting development since
climate control for
passengers/operators is a
significant issue in determining
the battery life in EVs.
Rheinmetall is clearly focused on
larger commercial vehicles and
not smaller sized passenger cars.
Some premium passenger cars are
already fitted with heat
pumps[3]. As an option they cost
about $1,300.

[1] Rheinmetall on Green Car Congress

[2] Rheinmetall news release

[3]Heat pumps for EVs explained

Article_1

AI's Appetite for Electrical Energy

03/25/2024

Steve Hanely recently published
and article[1] on
cleantechnical.com entitled: "AI
Has A Voracious Appetite For
Electricity, And That’s A
Problem". The whole article is
interesting. The concluding
paragraphs are:

"And yet, trying to limit the use
of AI to endeavors that are
socially beneficial is like
trying to get people to only
drive their cars when absolutely
necessary. Not gonna happen. In
order to maximize the limits of
computer technology, we will need
to vastly increase our
electricity generating
capabilities. We don’t have
enough renewable energy as it is.
How much of it should be diverted
to power AI, or mine Bitcoin, or
support online sports betting?

Those are the sorts of messy
questions that few people want to
answer and so they prefer not to
ask them in the first place. And
so we careen blissfully into the
future using more and more
resources to amuse ourselves. If
we continue to do what we always
have, we will continue to get
what we have always gotten — a
profligate waste of resources to
keep us entertained. Yes,
friends, we are that shallow."

My reponse to the paragraphs was:

I do not think the problem is so
much that we are shallow as that
we are committed to the
predominance of a specific social
institution: private credit
markets. The Mexican poet
Ocatavio Paz had this to say
about this institution:

"The market (by which he meant
private credit markets) is
efficient but it has no purpose.
Its only goal is to produce more
in order to consume more."

As long as the rate at which
money is being converted into
more money (which is to say the
rate at which consumption rights
are being converted into a larger
amount of consumption rights in
the future) is a central and
universal measurement of social
welfare it seems unlikely that
the fight against climate change
will gain serious traction. One
step forward will be followed by
one (or even two) steps
backwards.

I think that we need to create
community credit markets whose
goal is not to turn money into
more money but rather to create
and maintain infrastructure which
will serve the long term welfare
of humanity and of the biosphere
which supports us. If it is
impossible that we can create
such an institution because of
some aspect of the human psyche
which only allows short term
acquisitive greed to make
efficient decisions about credit,
then it seems likely that homo
economicus is an evolutionary
dead end that is unfit to survive
in the long term.

[1]AI Electricity Consumption