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[no dialogue]
>> male speaker: The computer will
tell the floor on the truck to move material in,
and then once it gets in the material will be moved.
>> male speaker: So it's more or less
kind of a holding area.
>> male speaker: Yep.
In winter if we were to have this all full of our densified
material, we'd probably have two or three days of storage
depending on how fast we...
>> male speaker: Okay.
And this is providing energy, or is it heating and cooling?
>> male speaker: This provides heating
and cooling for, heating needs anyway, 80% of peak demand.
So in the middle of January when it's just bitterly cold here,
we'll have to rely on some of our natural gas systems.
But probably as your campus is, this has got a redundant system
so that if one goes down we have other backup systems.
Yeah, initially though we did just try putting bails on here,
and there were some bars at the end that we hoped would break
them up but it just didn't work.
So then we went to grinding material and putting it on here,
and that didn't work.
This is our main gas fire here, and you can see it's got that
stuff in the bunker that's moving its direction and
dropping down into the hydrolic ram.
And then the ram is pushing it into that gas fire so.
I think before I show you [unclear dialogue] these are
student gasifier, so we teach with these.
With the last two years we've taught classes and we have
students do projects with them.
In fact, I've got an intern who is finishing up his project
right now and these use all of the same principles as the
gassifier but a little more manageable for students.
>> male speaker: Yeah, and I think
this is what we're trying to get going,
I don't know if they're homemade here or if.
>> male speaker: They can be homemade
but we get these from Allpower Labs from Sacremento.
And they're about 2500 a piece.
When this thing jammed, you can kind of see through this window
there's a little stuff in the one that's jammed, we literally
sent a bunch of people to hand it out
because it was tight in there.
But we replaced the cylinder a couple of times, upsizing it
each time, and it just didn't do it.
And so now we've changed the fuel and that seems to work.
Really fairly straightforward, it's just how much biomass, how
much air, and then how the two meet and interact.
So if you're getting a lot of air into your
particles, they react faster.
If there's more surface where air can
contact they react pretty fast.
That's why fluffy material is actually a problem for us
because this stuff reacts so fast it causes problems.
And we're also pumping air from underneath so it'll go up and it
will act more like some of your pulverized coal boiler systems
because the reactions are taking place so fast.
[unclear dialogue] So yeah, the way that we control the air is
by the variable speed fan, that one there.
And we've actually got one that pumps food gas back in because
if you use a food gas it doesn't have any oxygen so it's kind of
a filler air with no oxygen and it'll give you the right
blend of oxygen in there.
So you've got some different fuel products here.
We've got some chopped up material here which is our test.
>> male speaker: And that's the stuff
you said that's probably going to, that's the 50% grass.
>> male speaker: Well this is actually all
corn stover which is what we tried first, and then we went
to the 50% grass and that seems to work better.
So we've tried a lot of different things with it.
Here's an example of what happens when it gets too hot.
That's slag.
And that actually went all the way across, probably five feet
across the inside and five or six feet down the grate.
And they had to chop it, well they chopped it while it was
still hot so it broke up fairly easily, but that's a lot of work
to get those out.
And then as it's gassifying, the gas is going up and into the
boiler and the ash is dropping out and it comes through these
shoots here out and back to a wagon out there and we're hoping
that we can get that back out on the field.
[unclear dialogue] You won't see it on this side as much but
since it is a research project we do have a bunch of
temperature sensors on the other side, you see there's the one up
there, and on the other side there's about six more of them.
So we test pressure and temperature there.
And the whole system is really regulated by air flow and
pressure, air pressure in there.
In the gas chamber itself we keep a
slightly negative environment.
The one time we didn't do that we had little puffs of smoke
coming out all over the place.
But it's just about a third of an inch of negative pressure.
Then once we get the gas off it, starting up at this fan here
that will add more oxygen.
Once you add the secondary oxygen in there it starts the
combustion process.
So they call closed couple system because right after
[unclear dialogue], there are a lot of gassifiers that do have
quite a bit of distance between where they release the gas and
where they produce it.
Now one of the things in here, you notice the space here, it
was also the space out there, and that was designed for
research and teaching.
And already we've put in our first advancement in the project
or our phase two and that's a back pressure steam turbine.
That turbine will take our boiler steam and generate
electricity with it.
What we have here is, we have a boiler that will generate 280
pounds per square inch and then it goes out to campus at 15
pounds, and we use that difference in energy to generate
about 320 kilowatts in electricity.
So whenever the biomass plant's producing we can be using that.
>> male speaker: And that's energy
for campus?
Right away or does it just go?
>> male speaker: Honestly it goes mostly
back into the heating plant here offsetting fans and using it.
One of the other things that we learned in this whole process is
that we took samples of corn stover in Illinois to a
gassifier to test out and right away they told us there was a
lot of chlorine in it.
And that chlorine goes up the stack and that's kind of a big
problem because it joins with hydrogen, finds free hydrogen or
gets hydrogen and then forms hydrochloric acid.
And so one of the things that we didn't count on that our
consulting engineers didn't tell us right away, is to mitigate
that issue, we were going to have to have a large tank of 50%
sodium hydroxide here and so that's what this tank is and we
have to get deliveries a couple times a year, 50% is like syrup.
That's the grate and it goes back and forth slowly pushing
the material down.
That's another thing that we didn't really think about, the
shape determines how fast it slides down, so bigger chunky
material that prone to roll, will probably roll down here,
whereas small chips and things tend not to roll as much and so
we had to think about that now that we know more about the fuel
we're kind of having to consider things like that.
Speeding up or slowing down those grates in there to
accomadate whatever fuel is in there.
So in addition to the turbine downstairs, we put in an
absorption chiller unit in here as part of the phase two and
what we did we used an energy services contract
to do some of this work.
So we had an outside company put this in at their expense put
with the energy savings every year they get
a chunk of that money.
So we pay them off over time and after a while
the system is totally ours.
So you can see the combustion air from the gassifier is coming
in here, it's got air on the other side of the wall
combusting and coming through and
moving through to the boiler.
And the boiler system is a conventional boiler, the only
difference is it has a much bigger opening because it needs
that volume of throughput to get the energy to make the steam.
Natural gas just needs a small jet in there.
Now once you go through the boiler we have a set of tubes.
There's a duct out there that ducts the exhaust out and we
have a set of sample tubes that brings samples into this box.
This is part of our USDA grant was to put this in, and this
monitors our emissions.
So by law, we're not required to have this, but for research
purposes we thought it would be good to put this in, so we can
monitor our nitrious oxide, dioxide, co2, and then are
particular matter.
And one of the things we hope to be able to do is use our
facility for companies that want to test materials, or if we want
to do tests on materials we can do it in
our small system versus a big one.
So that's what this allows us to do.
This is also meant to be hooked up to the web so that other
people can see the data, so if we are teaching a class or we
have some researchers who are doing a project here, they can
remotely access the information.
And that goes along with the cameras and some
of the other data.
So I talked about putting sodium hydroxide, we have a wet
scrubber unit.
So the fuel gas is coming through and there's a mist
that's sprayed into it, and that mist will attract particles and
it'll attract the chlorine that's going through, and so
what we do is we put in a small amount of sodium hydroxide,
we've got a pH meter that regulates that and then the
water is sprayed in there and we produce salt basically, what the
end product is.
And then we also have a recirculating filter and so we
can send, every once in a while purge's itself, and
send the material down the main.
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