Hi Marja,

if you keep the temperature in the combustion column around 840 C, the 
filters won't melt and you still get reasonably well combustion. We ran 
thousands of filters that way without major problems.

Bjoern

-- 
Bjoern Wissel, PhD
EQAL Manager, Faculty of Science 
Adjunct Professor, Department of Biology
265.2 Lab Building
University of Regina
Regina, SK S4S 0A2 Canada
phone   306 585-4890
fax     306 337-2410
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