Energy efficient perlite expansion process

Patent · Tue Aug 31 00:00:00 EDT 1982

OSTI ID:6465740

Jenkins, K L

A thermally efficient process for the expansion of perlite ore is described. The inlet port and burner of a perlite expansion chamber (Preferably a vertical expander) are enclosed such that no ambient air can enter the chamber. Air and fuel are metered to the burner with the amount of air being controlled such that the fuel/air premix contains at least enough air to start and maintain minimum combustion, but not enough to provide stoichiometric combustion. At a point immediately above the burner, additional air is metered into an insulated enclosure surrounding the expansion chamber where it is preheated by the heat passing through the chamber walls. This preheated additional air is then circulated back to the burner where it provides the remainder of the air needed for combustion, normally full combustion. Flow of the burner fuel/air premix and the preheated additional air is controlled so as to maintain a long luminous flame throughout a substantial portion of the expansion chamber and also to form a moving laminar layer of air on the inner surface of the expansion chamber. Preferably the burner is a delayed mixing gas burner which materially aids in the generation of the long luminous flame. The long luminous flame and the laminar layer of air at the chamber wall eliminate hot spots in the expansion chamber, result in relatively low and uniform temperature gradients across the chamber, significantly reduce the amount of fuel consumed per unit of perlite expanded, increase the yield of expanded perlite and prevent the formation of a layer of perlite sinter on the walls of the chamber.

• Assignee: Manville Service Corp
• Patent Number(s): US 4347155
• OSTI ID: 6465740
• Resource Relation: Patent File Date: Filed date 19 Mar 1981; Other Information: PAT-APPL-245421
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
PERLITE
EXPANSION
ORE PROCESSING
BURNERS
COMBUSTION
EFFICIENCY
ENERGY CONSERVATION
FUEL-AIR RATIO
MINERALS
RHYOLITES
WASTE HEAT UTILIZATION
CHEMICAL REACTIONS
IGNEOUS ROCKS
OXIDATION
PROCESSING
ROCKS
THERMOCHEMICAL PROCESSES
VOLCANIC ROCKS
WASTE PRODUCT UTILIZATION
320304* - Energy Conservation
Consumption
& Utilization- Industrial & Agricultural Processes- Waste Heat Recovery & Utilization