Mark,
Try to find some used tractor trailer fuel tanks. They generally
hold about 2-300 gals per side and probaby have the right holes at
the right places, are designed to hold fuel oil and are not likely
to rot out. Or should a smaller version be desired there is always
used refer
They make good wash tanks for really large processors. AT the Berkeley
Biodiesel Coop we also used two of them to store several batches
before washing- we'd make several batches and put them into the first
IBC, let them settle for a couple of weeks while we filled the second
IBC (settling
Problem with those
http://www.joslebel.com/indiv_product_info.php?id=53catid=3
is that they are not completely air tight and the configuration might
cause uneven heat distribution which is why most processors are slim
rather than wide, as in the 90 liter one at journeytoforever
