Organic Residues That Can Be Cleaned; Organics Which Should Not Be Processed; Automatic Cleaning Cycle - ATS Pyro-Clean Instruction Manual

Organic Residues That Can Be Cleaned

Virtually any contaminant which is organic in nature can be removed at the normal operating temperature of the
cleaning oven, 950 degrees F. In recent years, new high temperature polymers have been developed which are very
resistant to heat and are not easily removed thermally. However, the numbers of these polymers are limited.

Organics Which Should Not be Processed

Plastics or polymers which contain large amounts of halogens such as chlorine, bromine, or Florine would not be
processed in the oven as they will react with the catalyst contained inside the oven trays and deactivate it. The
most common example of this plastic is PVC (polyvinyl chloride). The oven Oxidizer is designed to handle organic
residues which contain predominantly only carbon, hydrogen, and oxygen. Do not process any parts which may
emit vapors of toxic metals such as lead or mercury. Do not process any material which decomposes violently upon
heating. Nitrocellulose or other explosive materials are in this category.
Never clean any hollow, sealed glass or metal parts which might build up dangerous, internal pressures during the
heating cycle. Make sure all parts have vent holes or openings to allow pyrolysis gases or steam to escape as they
are formed. Any pumps, pipes, or vessels must have openings to allow pyrolysis gases to escape, otherwise they
could rupture in an explosion.
WARNING: NEVER PLACE GLASSWARE OR OTHER PARTS IN THE OVEN WHICH
CONTAINS RESIDUES OF VOLATILE, FLAMMABLE SOLVENTS SUCH AS ACTONE,
TOLUENE, MINERAL SPIRITS, MEK, ETC., AS THEY WILL FORM AN EXPLOSIVE MIXTURE
INSIDE THE OVEN CHAMBER.
SPECIAL NOTE REGARDING SILICONES: Silicone oil is commonly used in many
laboratories as a heating medium for carrying out reactions in glass vessels. Glassware which
contains silicone oil residues from the heating medium should be wiped off with a cloth or paper
towels or rinsed with acetone. Experience has shown that when silicone polymers are removed
in the oven, they leave a "cloudy" residue which etches the glassware and affects it appearance.
A round bottomed flask coated on the outside with silicone heating oil will be cloudy if cleaned in
the oven without removing the silicone. Glass stopcocks lubricated with silicone grease should
likewise be wiped free of silicone before cleaning the glassware in the oven.
Silicones are poisons for the catalysts used both in the oven chamber and the catalyst used in
the afterburner and should not be removed in the oven.

Automatic Cleaning Cycle

The Pyrolytic Oven is equipped with an Automatic Cycle Time Feature which adjusts itself to the load placed in the
oven. The cleaning time is limited by the processing speed of the oxidizer. The more organic residues or polymers
on the parts, the more smoke that will be evolved off the parts during the thermal cleaning process. The oxidizer
is equipped with a temperature sensor and controller which monitors the amount of smoke evolved off the parts
and controls the heatup rate of the oven to prevent the oxidizer from being overwhelmed by too much smoke. The
oxidizer control system will cut off the oven heaters if too much smoke is being produced. The oven temperature
seeks whatever temperature is necessary to produce the maximum amount of smoke the oxidizer can process.
Thus the oxidizer actually controls the heatup rate. When all the organic residue is pyrolyzed/vaporized off the parts
, smoke evolution will fall off, allowing the oven temperature to climb to the normal processing temperature of 950
degrees to finish the pyrolysis stage of the cleaning process.
MAN - Pyrolytic Oven - REV: Original | C. System Overview 9