kiln drying trivia

Frank Fusco

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This was found on the Hogan's Hardwoods website. It is interesting but raises some questions for me. e.g. how can wood have a 120% moisture content? Would that mean more water than wood? :huh: And: kiln dried in 24 hours seems like asking for the wood to curl. But, wadda I know? :dunno:

Kiln Drying Trivia

When drying a 107,500 board foot kiln charge of Southern Yellow Pine from 120 percent to 15 percent moisture content, 317,125 pounds of water is removed. This is the equivalent of 692 55-gallion drums or 38,060 gallons of water. It will release enough water from the lumber to provide 15-gallon shower for 2,538 people and still leave 5,4240 gallons of water in the lumber. This is in a high temperature dry kiln, and the drying operation is completed within 24 hours.
 
Wow, That seems way to quick. My lumber guy dries the wood in this order. One month of air dry, then about one month per inch of thickness, but this also depends on the type of would. I can not imagin haveing 120% moister in the wood and trying to remove it in one day. Maybe the meant 24 days.:dunno: :huh:
 
I have read that you can get 120% as it goes by weight not volume. I had a hard time with 120% to.
Bob
Yeppers...moisture content is calculated by dividing the weight of the dry material by the weight of the water (and then bumping the decimal point over a couple notches). So if the water weighed more than the wood, you could have moisture percentages higher than 100.
 
Wow, That seems way to quick. My lumber guy dries the wood in this order. One month of air dry, then about one month per inch of thickness, but this also depends on the type of would. I can not imagin haveing 120% moister in the wood and trying to remove it in one day. Maybe the meant 24 days.:dunno: :huh:

Does your guy typically load up 107,500 of framing lumber?
 
120% means you are putting 100lbs of wood (dry weight) and 120lbs of water into the kiln... Then you get 115lbs of 15% wood out.

With pine and a really good kiln it can be dry in 24 hours.. dont try this with hardwood :eek:

Cheers

Ian
 
Those numbers don't seem right. Either I am stupid or I skipped class the day they talked of wood and water and such but I think I would ask for a correction or explainition.

120% water is the slurry mix for wood pulp to make paper. Perhaps a decimal point is misplaced or I am out os touch with reality.
 
Nope... green wood can contain more water than actual wood, depends on the species, but generally green wood ( ie still in the tree) may be 50-150% water. Thats compared to oven dry weight.

Some woods will actually drip water from the endgrain as you are sawing it.

Cheers

Ian
 
Nope... green wood can contain more water than actual wood, depends on the species, but generally green wood ( ie still in the tree) may be 50-150% water. Thats compared to oven dry weight.

Some woods will actually drip water from the endgrain as you are sawing it.

Cheers

Ian

I'm not going to argue with a guy that has a chain saw in his hands. :eek:
 
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