Ken,
Feel free to use it and any photos from my site.
Thanks,
Brian
----- Original Message -----
From: Gabriel Orgrease <[log in to unmask]>
Date: Tuesday, February 27, 2007 9:31 am
Subject: Re: [BP] Oyster Shell Lime Burn Issues
To: [log in to unmask]
> Brian,
>
> I am working on the PTN print newsletter. Would you mind if I used
> this
> with slight editing to include in the PTN print newsletter?
> I pretty much like it just the way it is tho I might remove the 1st
> line.
> Thanks,
> ][<en
>
> Robinson wrote:
>
> >Jeffrey and fellow BPers, ,
> >
> >We gave burning a rick a try and here is the story.
> >
> >First, it was difficult in Savannah to get the proper mix of
> materials Jeffery
> >specified. Firewood is expensive ($225 per cord) and, of course,
> everything is
> >cut, split, and very dry. Also all you can get commercially is oak
> since most
> >folks don't want to burn pine due to the build up of pitch in
> their chimneys and
> >the subsequent possibility of chimney fire. As a result our rick
> was too small
> >(about 5'-6' in diameter and 5' high) and burned too fast (totally
> ash in about
> >6 hours). On the bright side, the circular design with the hole in
> the middle
> >worked great. The rick was never in danger of collapse, the shells
> continued to
> >drop into the middle as the rick burned down, and the burn was
> from the inside
> >of the rick to the outside. Packing the rick very tight in a spoke
> fashion kept
> >the free flow of oxygen from getting to the fire. One big problem
> we had was
> >that it was a windy day (5-10mph gusts all day) and this caused
> the rick to get
> >super hot and burn faster than it would have on a calm day.
> >
> >We tried to slake the shells anyway and got nada.
> >
> >Proposed for next rick burn:
> >
> >Get a better assortment of wet and dry wood and build the kiln
> larger and closer
> >to Jeffrey's specifications. This will take more time to assemble
> and since we
> >are doing this burn in the middle of Savannah in a big field
> logistics of
> >delivery of material creates a big headache.
> >
> >Questions:
> >
> >How long and how hot is the rick supposed to burn? We have been
> working under
> >the assumption that we need to achieve 1000 degrees F for 10-12
> hours. How hot
> >does a wood fire this size burn? Is there any problem caused by
> overburning the
> >shells? Should we get an infra red thermometer to measure the
> heat? Shooting a
> >thermometer directly at the fire seems pointless since the reading
> will be way
> >high. Do slaked shells react in a manner just like slaked
> limestone based
> >quicklime? I have never seen burned shells slaked so I don't know
> what to expect
> >as far as the reaction? I plan on taking some shells over to our
> pottery>department and burning them in a pottery kiln under
> controlled conditions to see
> >what results. I am looking at burning them at 1000 degrees for 10
> hours. Does
> >this seem right?
> >
> >We also built a small kiln based on Gerard Lynch's plans for a
> small kiln for
> >comparison. Here is this story...
> >
> >Our kiln was about 3' wide, 4' long and 4' high. We used modern
> hollow bricks
> >and lime mortar filling in everything as we went up. Unlike
> Gerard, we used wood
> >instead of coal to fire the kiln. It took a while (about 5 hours)
> to get the
> >kiln super hot. Reasons for this were that we were using oak and
> it took a while
> >to establish a good bed of coals and the kiln was very green so
> there was a lot
> >of moisture inside the walls that had to evaporate. The kiln
> developed a number
> >of small cracks due to the heat (we expected this) but the cracks
> did not hinder
> >performance. Looking inside the kiln we could see that the shells
> in the rear
> >were getting really hot (they were essentially translucent red)
> while those in
> >the front were cooler. On our next attempt we will try to do a
> better job of
> >evenly distributing the coals once the kiln really starts cooking.
> We had to
> >knock off at 8 pm so the kiln burned from 9am - 2pm in a warming
> phase and
> >really burned well from 2pm until 8pm. We will try to slake some
> of the shells
> >tomorrow (they were left in the kiln to cool). We don't expect
> much since we
> >were only able to burn them at a nice rate for 6 hours.
> >
> >Questions:
> >
> >Once again, we need to get better info on how long and how hot to
> burn the
> >shells. The fun thing about the kiln is that we can easily
> regulate the
> >temperature. Does the size of the shell impact the parameters for
> burning time
> >and temperatures?
> >
> >Overall, we learned a lot and we think we can easily work the
> kinks out of our
> >systems. I have seen several "interpretive" rick burns over the
> years but they
> >never actually produced anything usable. We hope to perfect our
> process so that
> >we can do a better job of informing the public as to how quicklime
> was actually
> >made on the colonial coast. Although I know it is possible, I have
> never seen an
> >oyster shell converted to quicklime. Any suggestions would be
> appreciated.>
> >Photos and video of our rick and kiln effort can be seen at
> >http://www.myspace.com/professor_robinson . Keep in mind that the
> first videos
> >of a rick burn on my site are from a NPS "display" we saw in October.
> >
> >Thanks,
> >
> >Brian
> >
> >Brian Scott Robinson, MHP
> >Professor
> >Savannah College of Art and Design
> >School of Building Arts
> >Historic Preservation Department
> >P.O. Box 3146
> >Savannah, GA 31402
> >
> >912 525 6940 office (Tues/Thurs)
> >912 262 2650 home (students emergency only)
> >[log in to unmask]
> >
> >
> >Brian Scott Robinson, MHP
> >Professor
> >Savannah College of Art and Design
> >School of Building Arts
> >Historic Preservation Department
> >P.O. Box 3146
> >Savannah, GA 31402
> >
> >912 525 6940 office (Tues/Thurs)
> >912 262 2650 home (students emergency only)
> >[log in to unmask]
> >
> >--
> >To terminate puerile preservation prattling among pals and the
> >uncoffee-ed, or to change your settings, go to:
> ><http://listserv.icors.org/archives/bullamanka-pinheads.html>
> >
> >
> >
> >
>
> --
> To terminate puerile preservation prattling among pals and the
> uncoffee-ed, or to change your settings, go to:
> <http://listserv.icors.org/archives/bullamanka-pinheads.html>
>
Brian Scott Robinson, MHP
Professor
Savannah College of Art and Design
School of Building Arts
Historic Preservation Department
P.O. Box 3146
Savannah, GA 31402
912 525 6940 office (Tues/Thurs)
912 262 2650 home (students emergency only)
[log in to unmask]
--
To terminate puerile preservation prattling among pals and the
uncoffee-ed, or to change your settings, go to:
<http://listserv.icors.org/archives/bullamanka-pinheads.html>
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