iandol on thu 25 jan 01
I suggest you contact the Museum of Industrial Arts at Newcastle upon =
Tyne, Northumberland, England.
They have remarkable archives and Curators who are willing to assist by =
supplying information about obsolete processes. There were several =
Hoffman kilns in the Tyneside and North Durham region, mostly under the =
management of the then National Coal Board.
Sump oil has a high viscosity and may be contain zinc and/or lithium =
stearate soaps which are incorporated to sequester carbon residues. =
These additive materials can cause flash glazing. It may also be =
necessary to provide some sort of heating, an immersion heater or hot =
water coil, to help with the flow. Sump oil also needs to be filtered =
before it reaches the burners and unless you can provide a high head =
from the storage tank, you will need a pump.=20
Wishing you success with this enterprise.