One day they're gone.

You know like we're.

Over one

hundred more

and more

about that later.

OK thanks.

Well thank you Chris.

For the invitation and

opportunity to tell you a little bit
about C O two capture technology.

What I want to do today.

I understand you've had a series of
lectures that talk about the role of C O

two in climate change and why we're
interested in doing something about it.

What I want to do today is give you some
ideas of what the possibilities that

we can do about SEO to capture and
what that might cost and

what the options available are so many
of you have probably already seen this.

This is a graph that shows how the
atmosphere a concentration of C O two has

been increasing over
the last several decades.

These oscillations are due to
seasonal differences in winter and

summer and the slope here is roughly
two parts per million per year.

This correlates pretty well
with the annual emissions

of C O two worldwide were roughly emitting
thirty three Giga tons of C O two and

there's roughly thirty five
hundred tons of C O two in the.

Atmosphere already so
adding another thirty gigatons per year

gives you about one to three
parts per million per year and

we can expect that's going to continue for
some time the scientific community as

a whole has in this report here
from the I.P.C.C. I.P.C.C. panel.

Agreed that climate change is probably
due to global C O two emissions and

we need to significantly
reduce these emissions.

If we want to avoid or

stabilize atmospheric C O two
concentrations in the future

this work shared the Nobel Peace Prize
in two thousand and seven with Al Gore.

So what I want to start out with this.

Where's the C O two coming from and
what are the issues with

reducing C O two levels and what
are the possibilities for capturing it.

So in this picture here.

I show a coal plant that's
pretty close to where I'm where

I'm from over here is a big coal yard
These are barges that have coal in them.

These barges probably are about
half a day worth of power for

so lots of coal comes in this river right
here is where the coal is burned and

these are water cooling towers.

About five miles away.

Is this blue lake here.

This is a real color seen from Google Maps
this blue color is due to the alkalinity

of the water that's come from a flight
from fly ash from this coal plant.

Now this coal plant produces about let's
say close to twenty five hundred megawatts

of power is the generation capacity and to
do that it burns seven million tonnes of

coal every year and the power production
from this is roughly forty one percent.

So that's like the car no cycle efficiency
of how much potential energy goes into

coal and how much electricity comes out.

The consequence of burning this is
the generation of about seventeen eighteen

million tonnes of C O two per year or

this almost fifty thousand
tonnes a day and that

C O two is coming out of the coal plant
at only fifteen percent concentration.

So we're taking coal which
is practically carb.

In burning it in air and
what comes out is a large amount of food

gas that's mostly nitrogen
eighty five percent nitrogen and

about fifteen percent C O two plus or
minus a few percent.

So this is a huge amount of
gas volume that we have to

treat in order to do
anything about the C O two.

We can't burn less coal.

Because then we would be
cutting down the power.

And so we're really stuck in a way
of producing this much C O two

per day that we have to deal with.

Now this amount of fluid gas would fit at
Sea Quest ration pressures which I'll talk

about in later in the talk of about one
hundred forty atmospheres in a cube that

was four hundred meters by four hundred
meters by four hundred meters that doesn't

seem like a large volume but this is only
the yearly output of one coal plant.

And the real issue is that the U.S.
has almost fifteen hundred coal plants.

And produces something like three hundred
thirty six thousand megawatts of power

producing close to to get tons of C O two.

So two times ten to the nine tons of
C O two emissions that are roughly

a fifteen percent concentration
in the volume in the flue gas.

So this amounts to about one third
of the total C O two emissions

of the US About one third
is from power generation

one third is from transportation
one third from industrial sources.

So the breakdown looks
something like this globally.

We're up here in around two thousand and

you're thirty gigatons most of it's
coming from solids this burgundy line.

This is coal burning the liquids
combinations of transportation fuel

natural natural gas is in here and
oil oil burning for

power generation and breaking it
down by country you can see the U.S.

has really been leading
C O two emissions for

quite some time several countries
countries in particular.

China is catching up.

But all of these show a trend upwards with
the exception of the Russian Federation

which showed a dramatic
decrease in C O two emissions.

In the late ninety's.

Probably we don't want to miss.

Their strategy of economic crash
to reduce our C O two emissions.

So we have to come up with
some alternative strategies.

For doing this.

So I think there are several ways to
look at what is this going to cost

the bottom line is that capturing and
Seaquest ration is a separation.

It takes work and it takes energy and
that's going to cost us some money.

So there's several ways to look at it but

let's take a simple view that doesn't
consider how we're going to do it but

just looks at consequences
of what it might cost.

So several estimates around in
the literature estimate that

maybe thirty dollars a ton is
a probable cost of capturing and

sequestering C O two that doesn't seem
like very good tons we have to deal with

and based on the amount of electricity the
three hundred thirty six thousand megawatt

generation capacity that I described
before at ten cents a kilowatt hour.

We have something on the order of
three hundred billion dollars a year

of revenue from electricity generation.

For the amount of C O two generated
from this two gigatons if we can do

that at thirty dollars a tonne that's
sixty billion dollars a year in the U.S.

something like twenty percent of what.

Companies are making selling electricity
will have to be used to compensate for

the cost associated with so
C.C.'s globally

that's going to be a trillion dollars
a year to deal with thirty gigatons.

And that's assuming the thirty that
we can do this at thirty times or

thirty dollars a ton.

Now it may not be necessary to deal with
all thirty gigatons maybe we can get by

with fifty percent capture.

Maybe we can get by with some other
methods that reduce the amount of

emissions.

But the point is a trillion dollars or
half a trillion dollars

doesn't really matter at this scale
it's still something trillion dollars.

Now if we thought about replacing the
power capacity so maybe we think you can

stop burning coal completely and switch to
nuclear or switch to totally renewables.

This is also very expensive so.

Generating new capacity is expensive
capturing C O two is expensive and

one of the points I want to make today
is no matter what we do in the future.

Regarding this problem.

It's going to be expensive.

The challenge is figuring out
what is the cheapest expensive

alternative in order to
make progress in climate.

Managing the C O two emissions.

So let's let's talk again about
scales here a trillion dollars sounds

like a lot but
how much money do we actually have so

one way you can estimate money is
by your gross domestic product

this is the value of all the final goods
and services produced within a nation.

Globally our G.D.P. is something like
forty five trillion dollars per year.

So one trillion dollars off of that
is maybe one to two percent of G.D.P.

worldwide is that too expensive
too to manage for this.

That's a good question.

This is again it's going
to be a decision if we have

to spend one trillion
dollars on something.

How do we spend it.

What do we spend it on that's
not a technical solution

that's something we have
to decide as people and

as societies that will be determined by
what's technically feasible in the U.S.

has something like twelve trillion dollars
G.D.P. and the annual budget for the U.S.

government was close to a trillion
dollars in two thousand and eight.

So a trillion dollars is a lot but
we have a lot of money to do things with

we spent almost half of that on defense
and maybe ten percent of it on education.

So again.

We have a lot of money we
spend it different ways and

we have to choose what we're going
to do with it in the future.

We're also pretty good at
spending lots of money.

So historically if you think about
how we spend large sums of money.

Mostly we spend it on wars World War
two is one that stands out that cost

close to two trillion
dollars in place in adjusted.

And inflation adjusted dollars.

Iraq over here we're probably over half
a trillion dollars since I made this.

Graffy year ago.

Other large things if we want to
build a new fossil energy plant.

So this is what I brought up before if you
want to replace capacity a new plant is on

the order of one to two billion dollars
And there were one hundred fifty one of

these planned at a total cost of one
hundred fifty billion in the past year.

Nuclear plants if we wanted to avoid C O
two emissions by changing to nuclear

we have to spend almost twice as much
on nuclear plants now in addition

to finding out sites where you can get
licenses and permits to build them.

So the main point I want to make
in this is if C O two capture.

If reducing C O two emissions
becomes a priority.

It is something that can be done if
there is technology that's feasible

policy that requires it and
public support for

it all three of these things have
to be in place in order for.

Any of this to move forward.

So now I want to focus more on what is the
technology for carbon management options.

We have on the left side here.

Reducing carbon intensity.

So that means getting energy from
sources that don't emit as much C O two.

These include renewables like wind and
solar nuclear power switching

fuels from coal to natural gas natural
gas has a higher energy density and

produces less C O two per energy on
the demand side that's you and me

we can improve efficiency and conservation
measures so that we use less energy.

Or we can imagine sequestering
carbon where we capture it and

store it permanently store
it because of the volumes.

And in order to reduce
the emissions of C O two.

So all of these three
things are going to occur

in different amounts over
the next few decades.

The how the the fraction of
it that occur will depend on

how affordable renewable
is compared to capture and

sequestration it will depend on
whether the government is sub.

Dies in renewable development
in order to make it happen or

whether they subsidise Seaquest rationing
capture in order to make that happen.

So I'm going to focus the rest of
the talk now on capture possibilities

of what can we do to capture.

C O two.

So looking at the base case scenario
of what kind of energy costs we're

talking about separation and
concentration.

That's what we mean by capture
separating it from the nitrogen flue gas

concentrating it so that it can be pumped
into some Seaquest ration reservoir

all of these cost some energy.

And the best that we can do in terms
of this energy is a thermodynamic limit

of reversible processes with
efficient second law efficiencies.

So in a simple way we can think about
the dilute C O two mixed in with nitrogen

this is what comes out of the power plant.

We have to separate that to go
from fifteen percent C O two to

C O two at one atmosphere.

This has to be compressed into a pressure
of about one hundred forty atmospheres

this is a typical pressure associated
with Seaquest ration that would go into

a pipeline and then you have to pump
it underground and the act of pumping

it underground displaces some water and
there's some energy associated with that.

So here is an ideal mixing
kind of separation.

This is roughly nine kilojoules permanent.

All of this is coming from this
paper here just to work out

a simple thermodynamic analysis of
a minimum cost of energy separation.

So nine kilojoules promote C O two is
roughly five percent of the output of

a power plant.

The compression here.

Is about thirteen killed Joules
per mile roughly seven percent

of the power plant output and this to kill
Jews promote this approximately one or

two percent of a typical power plant so

adding these up gives you know something
in the order of eleven to thirteen percent

of the output of a power plant is
going to be used for capturing.

Compressing and sequestering C O two.

That's the minimum amount
we can hope to spend

if we could do everything
thermodynamically reversible.

The reality is we can't do everything
thermodynamically reversible.

Because you can't do it at
rates that are feasible and

you can't do it if the rates aren't
feasible then the capital costs are very

large because you do everything
slowly in order to do it reversible.

So there's two ways to
look at this penalty.

It's either the fraction of fuel that's
going to be used to provide that energy

in which case new capacity has
to be developed to make up for

the loss of capacity.

Or it's an additional fuel that has to be
burned in order to keep a constant output.

This means additional operating costs.

So you can think of it as we need extra
capital cost or extra operating costs.

Either way these two are related.

So with these perfect
second law fission seas and

really good waste heat integration.

In what I showed you before the
thermodynamic limit of parasitic fuel cost

is about eleven percent.

That's the the very best
that we can hope for

that we have to give up eleven percent.

Estimates of today's efficiencies
with what we know how to do today

that account for irreversibility S.

and the fact that we cannot approach
the thermodynamic limit and have

practical rates suggest cost estimates
of forty percent her acidic fuel cost.

So that's what we could do
today we could lose forty

percent of our capacity in order
to do capture and sequestration.

And realistically a target
of probably thirty percent

on existing technologies is that what
we can probably achieve in the future.

So we either lose thirty percent
of our capacity to do capture or

we have to increase by thirty percent.

In a carbon neutral way in
order to achieve capture and

sequestration with today's
technology in burning coal with air.

But that's not the only way to do it.

There are other methods for.

Separations and the C O two
capture is a separation challenge.

What I've described already is what's
called post combustion separation

you take your fossil fuels plus air and
you burn it.

You get the mixture of nitrogen and
C O two.

This goes into some separation module that
will separate the nitrogen in C O two and

then C O two goes down here to
a Seaquest ration reservoir.

It's called post combustion because
you separate after the combustion.

In pre-convention separation.

We have a different approach to doing
power generation we start with air and

we do a nitrogen oxygen separation.

This could could be cryogenic distillation
it could be other types of oxygen

separation but the point is we get pure
oxygen and we burn the fossil fuels with

pure oxygen and by doing that you get
concentrated C O two and water and

the water is easy to
separate by condensation.

And you have concentrated C O two that
goes to a sequenced ration reservoir.

The third possibility is I call
it alternative combustion.

Some people call this
also pretty combustion.

And then as we combine gasification
where we convert fossil fuels and

steam into send gas in the city
gases then separated so

that C O two goes this way and
hydrogen goes into a combustion down here.

We're all that's coming out as water.

So these are the integrated
gasification combined cycle ideas or

solid oxide fuel cell ideas
that combine separation and

combustion in a process that
allows you to capture C O two.

So I'm going to give a couple of ideas
on what this technology looks like

a little bit of this technology and
a little of this technology.

In the rest of the talk.

So let's talk about post
combustion capture conditions.

The process for
power generation here is you have coal.

It's burned with air the heat from.

That is used to make steam in
the steam goes through turbans.

The flue gas that comes out and has to go
through a sulfur scrubbing unit to get rid

of sulfur so that we don't have acid rain
problems and what comes out is roughly

thirteen to sixteen percent C O
two forty five percent oxygen.

There's always residual oxygen
because otherwise you have

lean combustion conditions
that causes coat formation.

They're saturated in water because
the the sulfur scrubbing unit

has a lot of water in it and
there's minor impurities like mercury and.

Arsenic and
other other things that exist in coal and

the rest is nitrogen there's some
variation in this just because different

coals have different carbon contents and
result in different levels of C O two.

Temperature is typically
sixty to eighty degrees C.

and it's slightly above
atmospheric pressure.

And just to remind you what the scale of
this problem is we make a lot of C O two.

Much more C O two and much more fluid
gas than typical cryogenic air plants

are able to handle the typical
The biggest cryogenic their plants

in the world maybe do one tenth
of the volume of gas in a day.

So it's really a challenge to devise
engineering structures that can handle

this amount and the capture goal is
about one hundred forty atmospheres or

this many P.S.-I and it needs to be dry.

If it's going into a pipeline.

So that establishes the conditions and
the goal to get from

moist local concentration C O
two to dry concentrated C O two.

And it needs to be dry because wet C O
two and high pressure is very corrosive.

So if you have a pipeline
with C O two in it.

You will make lots of carbonic acid
that will corrode the pipeline.

So the three three basic ways to
approach the separation challenge

you can have liquid absorbance where C O
two is selectively dissolved into a liquid

liquids or to.

Bickley liquid means where there's an acid
base reaction between the meat and

C O two.

Chilled methanol or glycolysis where
you rely on high solubility of C O two

in these materials were
children Monia which is

a little bit of both you can have basic
ammonia reacting with acid fuel to.

Another approach is selective sore passion
where C O two selectively adds orbs on

a surface.

So you have some surface that C O
two selectively sticks to and

nitrogen does not and so

you can achieve a separation by cycling
between adsorption Indy's the option.

These can be supported to means or
they can be in organic materials as well.

And finally membranes are is
an approach where C O two

selectively permeates a membrane.

So you have a barrier that C O two
selectively goes across another other

molecules don't.

These are going again be made of
supported it means around a quick wit.

There is and sematic membranes
electro chemical membranes.

And probably other types
of membranes as well.

So let's talk about the means first this
is the most common way of separating C O

two right now there are several types
of A means we have primary means here.

This is a secondary Ameena has one
hydrogen and two are groups of tertiary I

mean and this is an Amity in structure
all of these are basic molecules that can

react with the acid gas of C O two or
any other acid gas in in their.

There's several issues associated
with these They're usually

only about thirty percent
in concentration in water.

And that's for a couple of reasons one.

They're so basic that they're corrosive
and you have to put them in water

also to manage to discuss the of these so
it's easy to move them around.

They're usually quite toxic and
volatile and

these are means are prone to oxidation
where they can make nitric oxide.

And then they're no longer useful.

In.

The I'll show you in a moment.

Why these are so
energetically expensive to regenerate.

But they're very strong basis so
they sort of C O two very well.

On the other hand they do work and
there are lots of industrial processes for

using things like methanol mean or
die off and

all I mean in order to capture C O two
when efficiency is not a great concern.

Hazards of switching computers.

These are back and forth of equilibriums.

So the chemistry here is important the
chemistry is important to understand where

the energy of regeneration is coming from
as well as what the story is going to be.

So the two kinds of C O two mean

chemistry is that are described
most often in literature.

Are these carbon is what are on structures
where two means can react with C O

two to form this carbon Amyt structure or
C O two and one of Mean can react.

With water there should be a water
in here to form a body carbonate

under flue gas conditions there's
always lots of water around and

so these reactions are much more
likely to be relevant under.

Flu gas conditions where you
form these by carbonate salts.

This is essentially a base and then C O
two can react with water to form carbonic

acid and so you have a carbonic acid base
reaction forming these salts on the right.

And these salts or what have to be
regenerated when you do the stripping to

regenerate the sorbent are solvent and
give off the C O two.

Part of the reason why there's a large
amount of energy to regenerate these

is these the means are only
thirty percent in water.

So in this schematic here this
shows how these systems work over

here is the sorting column where.

You have the solvent flue gas
comes in the bottom C O two

reacts with the a means as it bubbles up
and so clean flue gas comes out the top.

At the bottom here this is rich in C O
two it comes over to a strip in column

where this column is now heated up say to
one hundred fifteen hundred twenty five

degrees C.
in order to reverse the reaction and

shift the equilibrium back over
to C O two in the gaseous.

But in order to heat this up you have to
heat up to seventy percent of the water

that's carrying the amine during
the regeneration and that water

that heat to heat up the water is
essentially lost because it doesn't help.

Water is just a carrier that
gives you the concentration and

properties of the mean that you want.

So the inefficiency in this process comes
because you have to heat up all the water

to drive the regeneration
at some reasonable rate.

After you regenerate it then it
comes out the bottom lean and

comes over here where
it continues to cycle.

So this is the basic process for
liquid solvents for

capturing C O two the capital costs
are pretty big because you need

these these kinds of columns the energy
costs regeneration are very high

because you have to heat up the water and
you have to heat up the amine

C O two complex high enough to make
it fall apart and give off C O two.

There are several other
solvent approaches.

Ones that go by names you may have heard
of is Rectus on this is chilled methanol

so chilled Methanol has a very
high solubility of C O two and

it's fairly selective but
only at minus eighty degrees Fahrenheit.

The good news is regeneration is that
minus thirty degrees Fahrenheit.

So you just have to expose
it to room temperature and

it warms up to minus thirty.

But you now have to cool or refrigerate
which is very very expensive and

the levels of flue gas
that we're looking at.

So let's all as a similar approaches
dimethyl ether is of polyethylene glycol

So this also is relying on physical
solubility of C O two in the solvent and

also works at fairly low temperatures.

Chilled ammonia is another popular.

Approach being looked at now children
Monia reacts to form ammonium by carbonate

and ammonium by carbonate is very easy to
decompose that reasonable temperatures.

The downside of this is that you have
to operate at very low temperatures.

In order to keep the ammonia volatility
down and that leads to higher refrigerator

in energy costs one of the plus
sides is sulphur tolerance.

So if there are socks and
knocks in the stream.

Here you make ammonium sulphate which is
actually valuable as a fertilizer product.

So you can reuse ammonium
sulfate in that sense.

Nobody wants to because it's
not high quality fertilizer.

But it could be some other work here.

Charles Acard and his coworkers are
looking at reversible on a quick woods.

So this isn't a new concept in using

something other than water to
form the bicarbonate salt.

Maybe another alcohol to form an alkie or
carbonic acid that can react with the base

and has different thermodynamics
associated with regeneration and

the interesting properties
are with respect to volatility

because they are in the quick
wins are not volatile.

And finally there's a quick
spaces that are work.

That can work.

So potassium hydroxide is very
effective at capturing C O two.

But the regeneration is very expensive so
swinging between K O H and

potassium carbonate or potassium
carbonate potassium by carbonate.

Takes a lot of energy to do that swing.

But those are essentially the solvents
that are being used today.

So I think so

far I've just told you that they're very
expensive and inefficient to use by.

The principle is very is a good one.

What needs to happen is in
the future we need more work in

understanding the molecular origins
of the C O two and mean interactions

right now we know that it means
the standard means will capture C O two.

But it captures it much too strongly so
on top of the water heat needs.

There's too strong of a C O two
a mean Bond to be efficient

What we need is to understand how do
molecular properties of the means.

Can we functionalized the amine so
that they grab C O two less strongly and

are easier to regenerate and
how do we understand the kinetics

of regeneration and
particularly the role of moisture.

So can we devise organic solvents with
lower he capacities or devise a means that

are less corrosive to the system so that
you can minimize the role of moisture.

In there.

We need new concepts and

destabilizing these so right now
the problem is this complex is too stable.

It takes too much energy to
give it up to regenerate it and

actually the formation is so

exothermic that you have to deal with the
heat that's evolved during the capture.

A major advance or breakthrough is
needed in novel regeneration schemes.

So far we use heat you heat it up
until it regenerates if you can

devise photochemical or electro chemical
or even novel chemical cycles that can

do the regeneration we can fundamentally
change what the efficiencies.

In these processes are compared
to what we can do with heat.

And this contactor and heat exchanger and

systems integration is something else
that is desperately needed in this field.

So the efficiency of heating
of getting heat in and

getting heat out is a major contributor
to the high cost of these systems and

whether we design new power plants
with integrated capture systems or

retrofit old plants is something that
has yet to be really determined.

We have an awful lot of plans.

Fifteen hundred.

That could be retrofitted that may
be a better solution than trying to

build one thousand new plants
that have integrated capture.

So let's talk a little bit
now about solid sorbent So

this is moving away from a liquid that
absorbs either chemically absorbs or

physically absorbs to solid materials
depicted here that have poor structures

and these little green
stars here represent.

Functional groups on the surface
that can interact with C O two.

These can be a means.

That's what they usually are they can
be poly America polyethylene Amine or

Dundrum or.

We're doing work on D.B.U. in our group.

Chris Jones here is working on
grafted to means that look like this

where they start with them is European and
grow Apollo America mean

from the surface that has a large
number of functional groups in it.

The biggest advantage of solids is that
the supports have much lower He capacity

than water.

So you have much lower heat
load to heat up the sorbent and

then it's easier to cool back down.

And we have better mass transfer
because these particles are porous and

you can design the transport
properties in me as a porous materials.

So what I want to talk about
with sorbent is a simple

idea about what is what do we
mean by optimal sorbent So

we have this simple Langmuir absorption
model let's imagine that your sorbent has

a fixed number of sites each site
can absorb one C O two and let's use

the Langmuir model that we have a gas or
bait site in equilibrium with the C O two.

We can express that gives free energy
of absorption in a form that looks like

an intrinsic Delta G. of absorption and
standard state a correction for

Delta G. at any temperature that's
not the reference temperature and

a correction for any pressure
that's not the reference pressure.

And from this expression here we can do.

Find an equilibrium constant and
then in the laying there isothermal

this equilibrium constant tells us what
the fractional coverage of a means and

C O two are.

So if we can define or calculate what
Delta Jeus we know what the equilibrium

constant is if we know what
the equilibrium constant is we know what

the fractional coverage is for any set
of conditions pressure and temperature.

So over here if we look at this blue line.

This shows what the isothermal for
capture looks like.

So given a delta G..

We can see that for a delta G.
of less than this value.

We will have completely covered
the surface every I mean will have one

C O two on it if you switch
to Delta Geo over here.

There will be node C O two
is on the surface at all.

So we can look at now the coverage
as a function of the delta G..

And the temperature in the pressure.

So here we have capturing at three hundred
thirty K. and point two atmospheres.

This is what the coverage would look
like as a function of Delta G. not.

What does that mean.

This would be in the mean
that binds very strongly.

This would be in a mean that
binds intermediate This isn't to

mean that binds very weakly.

So I mean that binds very weakly
at a pressure of point two and

three hundred thirty K.
would not have any C O two on it at all.

We can now look at what the curve would
look like for a higher temperature and

lower pressure.

So if this is a capture condition.

This is a regeneration condition.

So at three hundred seventy three K.
you find that this I mean here

has high coverage but
this is mean over here has a low coverage.

So for
any given to mean each point on the X.

axis in essence corresponds to one to
mean with one binding energy of C O two.

And these different curves correspond
to the adsorption conditions and

the regeneration conditions.

It's the difference
between these two points

they give you the capacity of the amine.

Four capture.

So it's the capacity at the capture
minus the capacity at regeneration and

that's what I show in this red
line here is the difference.

So this red line now is that what
we call the Delta loading or

the working capacity of a C O two sorbent.

And for a set of conditions three
hundred thirty K. point to atmosphere

capture three hundred seventy three K.
point zero one regeneration.

There is one to mean with
an optimal Delta loading.

And it has a delta G. of roughly
minus twenty three take L's per mile.

If I hadn't a mean that
binds any stronger.

I have a very low capacity
because if it is.

If the delta G. is much more stable
then we will not be able to get anything

off the surface by heating it up in
the other hand if you go to this side

then the Ameena so we can never get
anything on the surface to even deserve.

So for every set of conditions that you
can imagine different coal plants might

have different temperatures of capture
different temperatures of regeneration

that might vary throughout
the year seasonally

in the summer versus the winter.

These are not big temperature changes but

you see there's an optimal amount optimal
Delta G. and anything left or right.

Gives you suboptimal.

So that means if we had high temperatures

that were capturing out we might
want to use a high delta gene.

If we had low temperature if
you want to use a load L.T.G.

in order to get maximal capacity and
maximum efficiency in this process.

So I'm going to start speeding up a little
bit on covering each topic because some

things get a little redundant in
future needs of solid sorbent we have

really a need for very low heat capacity
supports the heat capacity of the support

directly goes into Lost efficiency
from heating up to support

we need high chemical stability
in the support and the Sorgen.

So these.
Or things that you want to cycle many many

times in food gas environment and
we need supports that

will not fall apart after hundreds
of cycles in high temperature steam.

And we need optimized
absorption properties for

particular conditions so different coal
plants may need different sorbent and

there is a real need for being able to
change the absorption properties of them.

In order to get high.

Delta loading zone or capture conditions
and high selective and toward C O two.

It turns out more secure is a store
key metric part of this reaction.

But you need to be running right
on the story you metric limit.

So we don't want to absorb five miles of
water per mile of C O two that will be

an additional parasitic power loss because
you have to do the water in order to get

the C O two off.

Finally we have to get a better
understanding about the kinetics of

absorption and what I described on the
previous slide is a simple thermodynamic

argument if you're kinetically
limited in the way you run your system

your Delta loading will be actually
lower than the thermodynamic limit and

the last point here is how do we
integrate a sorbent into a power system.

There's major issues with heat
management in solid beds and

there's major issues with solids
handling if you go to a fluid ised bed.

So how we can efficiently
in Agree sorbent into

power systems the still
a question to be determined.

All right let's talk a little

bit about pre-convention approaches this
is an approach where instead of doing

a C O two nitrogen separation we
focus on nitrogen oxygen separation.

The idea being you have pure oxygen
running into burning fuel and

what comes out would be C O two and water.

There's almost always a recycle because
pure oxygen burns fuel at something like

five thousand degrees.

So we recycle C O two to dilute this down
to roughly twenty five percent oxygen.

So.

Little bit higher than air because
C O two has different heat transfer

properties the nitrogen and so you need a
little bit higher concentration of oxygen.

But what comes out here a C O two and
water water is easy to condense out

in the ideas that you have
concentrated C O two coming out.

This.
This is a particular challenge and

I'm just picking one technology here
to talk about oxygen separation

cryogenic distillation is not an efficient
way of doing air separation for oxy fuel.

One we don't need that much liquid
nitrogen that's being produced for

the amount of oxygen.

We need and to the cryogenic aspects
make it difficult to be as efficient.

So one of the leading approaches now is
using materials that are similar to solid

oxide fuel cells.

These are ceramic materials
that conduct oxygen ions.

So you can make a oxygen ceramic oxygen
membrane that runs that eight or

nine hundred degrees C.
similar to a fuel cell.

Yes ofc and by putting a high pressure air

selectively drive oxygen across
you can either use high pressure.

This is ten or twenty atmospheres.

Or you can apply an electric
potential to drive oxygen across.

These membranes our group is working
on an approach similar to this but

using low temperature aqueous based
electrolytes where we can drive

hydroxide ions across this interface and
separate oxygen by that mechanism.

The other approach that people talk about
an integrated gasification combined cycle.

This is a really complicated
system that combines

chemicals electricity and carbon capture.

So why chemicals and electricity.

The main idea is you have
an air separation unit

down here that's providing pure oxygen.

You have a fuel preparation train
here that goes into a gas a fire.

So fuel plus oxygen in
a gasifier leads to send gas and

send gas can be used to make
a variety of chemicals.

You can.

Make methane all fish or
tropes Catullus us to make hydrocarbons

you can do quite a bit with syn gas.

So one option in this is
is to make chemicals.

Why would you make chemicals because
people or people want to buy them.

So this is a way to have a revenue stream
in a power plant whether it makes sense.

Depends on how valuable the electricity
is so you can run an optimisation

that says how many chemical should we make
how much electricity should we sell and

you might learn that you do one or
the other but the possibility is here.

So now we have seven gas the part that
doesn't go to chemicals goes through

a variety of gas cleaning water
scrubbers This gets rid of cyanides and

C.E.O.'s and eventually comes over
here to a water gas shift reactor.

So water gas shifts takes H two N C O and
makes more H two N C O two with water.

So now you have here
a hydrogen C O two separation.

Problem you separate out the C O two that
can be done with membranes it can be done

with you can separate out the hydrogen
instead through Palladium membranes or

other kinds of hydrogen
separation technologies.

But now over here is where the magic
of combined cycle of curves you have

hot gas coming through here.

That's expanded to retore been so
hot hydrogen goes through a turban and

generates power then
the hydrogen is burned to make

steam that goes through a second turban.

So this is the idea of a combined cycle.

You do two things with the same fuel and
the combined cycle of gas.

Plus steam turbines gives overall
efficiency limits that are better than

a single stage car no engine and you can
get up to maybe sixty percent efficiency.

Now there are only two of these in
existence in the US that I know of.

There were plans for
several But Future Gen got.

Reallocated let's say.

And there may be another
one in the future.

But the bottom line is these
plants are very expensive and

you can see why they're very complicated.

You have air separation units gas of fires
shift reactors all these kinds of turbans

this is like three kinds of conventional
power plants slam together in one.

It's complicated and it's expensive but
there's only a handful of these and

I would say these are at the same stage
that nuclear was thirty years ago.

So thirty years ago nuclear plants
every single one was unique

had its own set of plans
it took ten years to get.

All of the permits approved four of them
were sort of in the same situation here.

The two that exist are unique.

There is no company selling a plan for
an eye G.C.C.

plant yet several are working on it.

Companies like Siemens are developing
plans for I D C C plants.

And if there is an order it's it's only
it's a stated interest in maybe buying it.

One day.

OK so solid oxide fuel

cells are still another approach to
the separation reaction problem so

far we've talked about combustion in one
chamber separation in another chamber.

In the solid oxide fuel so we combine both
concepts into separation and combustion.

We have a solid oxide fuel
cell membrane that's a.

An electrolyte stabilizer
Konya on one side you have in

Occident usually it's air going across
here and the air the oxygen in the air

selectively goes across this membrane in
the form of two ions zero to minus ions

on the other side you have a fuel in the
fuel can be send gas it can be it can be

a lot of things gasoline hydrocarbons
can be hydrogen and the oxygen

at this interface reacts with the fuel
in order to produce electricity so

fuel is oxidized on this side electrons go
across here and reduce oxygen on the side.

So the solid oxide fuel
cell combines the so.

Operation and
combustion into a single device so

that ideally what's coming out here.

If you have complete conversion
is C O two and water again and

only depleted oxygen or
depleted air on the side there so

if seas run at very high temperatures
eight hundred to a thousand degrees C.

So they're often combined with a turban
right afterwards because the gases

that come out of here are very hot and
can be expanded through a turban.

So the combined S.U.S.E.

turban systems can approach
efficiencies of like sixty percent.

Which is what this these
hybrid systems are so

these are these are subjects of
very active research right now.

There is a solid energy
conversion Alliance Program

at the National Energy Technology Lab
that funds a lot of work

trying to get industry and
academia together to solve

problems like material problems stability
to impurities is a big problem.

These ceramic membranes are are somewhat
fragile and getting seals that operate at

seven to eight hundred degrees C. is also
challenging startup is challenging because

you go from room temperature to high
temperature very quickly and stability

to impurities is remains a problem across
the board when you talk about coal.

So I'm going to finish up in
another slide or two here.

I'm going to assume that we can
solve the point source problem.

Everything I talked about
applies to point sources.

Those are power plants that aren't moving.

You know where the C O two is coming
out you know how fast it's coming.

But those are only about one
third of the emissions of C O two

approximately another third
come from transportation and

this is very challenging because
transportation is distributed

the C O two emissions come from cars
all over the place all times of day.

And there's a wide range of
ways to think about doing it.

So one way we can think
about transportation fuel.

Is carbon neutral fuels.

If we're not going to take the bottom
route where we go completely electric

and drive.

Everybody drives with batteries
some of us will some of us

will have to drive too much trucks big
vehicles will never run on batteries

a way to do it is through synthetic
fuel so bio fuel is one approach to

this we have plants that grow they
capture C O two from the atmosphere.

They take solar energy and
in a passive way they use that to create

carbohydrates and then we do chemistry and
Catullus us on biomass to create biofuels

an alternative approach to that would
be to capture C O two ourselves.

Combine that with sorbent regeneration and
hydrogen production.

This could be a variety of techniques but

probably it will be something
like water electrolysis.

The oxygen from that would be used in an
oxy fueled fire fossil plant to make C O

two that maybe will be used for enhanced
oil recovery or sequester ration were will

feed up into here and will have
maybe biomass or industrial C O two

inputs into here and the hydrogen in C O
two will be used to make synthetic fuels.

The synthetic fuels then will be fed
directly into our transportation

which will close the cycle like this.

So this this is a very
very high in the sky

kind of approach to thinking
about synthetic fuel.

But the point I want to make in here is.

I made a good case for
the fact that we're going to need a lot of

extra energy a lot of extra
power generation in order to do.

C O two capture this is where
the majority of it may come.

So instead of trying to build additional
fossil energy plants we could

build renewable energy at a level
that would support C O two

capture in a transitional
period away from fossil energy.

The advantage of doing that is that
capacity exists we still have to learn how

to do this more cost effectively and
we can't do.

More cost effectively
without doing it in some way.

So this would be a way to
address transportation emissions

in addition to dealing with hybridizing
renewable energy with fossil energy.

So let me summarize here that C O two
capture is a very big challenge but

in my mind a very necessary step.

If you're going to do sequester
ation there are many approaches

to thinking about it.

They're all expensive and technologically
challenging and none of them

are clear winners at this point
different approaches will be needed for

different applications and lots of
work needs to be done in many areas.

So I don't want you to come out of this
thinking that C.C.'s is the only way

we will look at other options and but

they're all equally if maybe not
equally they're all expensive.

They all will require major
changes to enforce infrastructure

major changes to our way of life.

And the solution will not just
be technical in nature but

will require public support and policy.

But the bottom line here is
we have to do something and

it's going to be expensive so.

Let me acknowledge a few people at
the National Energy Technology Lab who I

collaborate with Anthony
could Jeanie Geo Henry.

Penn line are people that I work with Evan
David Mack or some of my collaborators.

These are some of the students that have
helped me with with some of the work we do

in this area and
with that I'll take some questions.

Thank you.

OK So you know I'm sure we're.

Yeah that

sounds very reasonable.

Whether that's you know it's a point.

It's a foot philosophical point
of how much growth is necessary.

In G.D.P. and it's probably disingenuous
of me to say that we should hold

growth because I had in a particularly
comfortable stage of life

where growth isn't really
going to affect me.

But it will affect others.

Which is where growth
is occurring right now.

And I was like

yeah yeah that's really
a partial pressure.

So if you were running steam at one bar.

That's Well you know

I was so close

so sure.

So the idea there was you have this
is just taking a packed bed reactor

you run in C O two through
it until it saturated and

that gives you the capacity of capture and
then if you flush it with steam.

If you flush with until it's gone.

You know all.

Comes out then the pressure is quite low.

That's the basis of that analysis.

I guess.

That's a good question.

I'm not sure because presumably
the liquids have much higher density of

of sites than than the sorbent
that's a good question.

I don't know or

so

there are people that go to
to make polymers the issue

is how much we make we don't make we don't
need anything at the scale of C O two.

We make except the fuel that made it so

in that sense you know the chemical
industry is a drop in the bucket in

scale compared to the amount of C O
you were making so you could satisfy

all of the C O two needs and still have
way more than we know what to do with

your

life

man.

Fair enough.

Yeah it could be.

Yeah.

So the the commercial you can
buy commercially available

seas now that are in their
kilowatt stack size.

Maybe up to two hundred kilowatts I
think that's the they tend to come in

in small units like that and that's how
they scale it is that what you mean

there are scale in the sense that I.

Think the way they view it is you
take two hundred fifty kilowatts and

multiply it by until you
get the scale you want.

That's how they're going to that's
how they're going to scale them

very very

had a nice discussion with Andre FEDOROFF
own on this concept earlier

it's not exactly that but
it's pretty similar.

He would have compressed C O two that
would that was liquid on the car

until I had that conversation with him
I would have argued that the cost in

the weight of sorbent that would go
on a car would just be too high and

for that's probably true.

If you can compress it in
liquefied it might be more true or

might be more possible

that you know.

Or are really.

OK.

Yeah but

in principle any kind of base would work
a means or the most common organic basis

hydroxide or another type of base
which I briefly talked about they go.

It goes hydroxide carbonate by carbonate
as in organic materials in organic

materials fourth guys applications just
binds you to much too strongly and

in terms of other types of organic basis.

There are some phosphorous based
functional groups that are used as organic

basis but I don't think anybody really
thought about them for C O two capture.

Yeah that's a good question.

So there's there are several
aspects to that question one is

what happens if it doesn't work
the other is what happened.

How long will it work.

So there are several ways to look at it.

We have for many decades pumped C O two
into the ground for enhanced oil recovery.

And are starting to pump C O
two in the ground at scales.

Approaching relevance to sequester ration.

So in the past there have been
thousand tonne injections

over the next few years there will
be a million tonne injections.

And it's an open question of
Where does the C O two go and

how long does it stay underground.

If it stays underground for

ten thousand years that may be good enough
that stays underground for one year.

That's probably not good enough.

So that's an open question.

It's unclear some recent papers in science
suggest that most of the C O two is going

to dissolve in water and
there are now lots of questions of

if there's lots of C O two dissolved
in water is all of the wellhead cement

that's keeping these sites
sealed going to dissolve or

is it going to dissolve other rocks
that you know release other things.

So this is a big question.

And part of the reason why
we need a balance of C.C.S.

research with renewable research and
other energy option research to be done.

So I can answer that question
of is it going to work.

People are trying to
understand if it work.

And if we determine that it won't will
shift our resources to other forms of

research in renewable energy.

If it doesn't work we'll do more of

an injury lawyers.

Right right.

Sure.

One of the sequester ration
partnerships that is getting funded for

injecting a million tons is getting
the million tons from age your

geological reservoir are going to.

Because otherwise you have to
pay one hundred dollars a tonne

you know

which one is lagging there.

It's there it's like
a triangular chicken and egg.

We won't pass policies until there
are technologies that are feasible

politicians won't know technologies
are feasible until we develop them and

show them that they're feasible in a way
they understand that they're feasible and

the public will have to

have to make some decisions to make
life more expensive in a way right.

So it's hard it's easy for
me to see the policy technology link.

It's I'm totally unprepared to talk
about the you know public link

of what what is the public
willing to spend money on and

willing to accept legislation on
because policymakers won't make policy.

If the public is not behind them as
it will only last one election cycle.

Yeah OK.