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A typical application for surface heating is Hoppers.
Reliable and effective hopper heating systems play
an important role in the removal of flyash from
precipitators and baghouse hoppers. The hopper
heater must be designed for preheating the hopper
to prevent moisture condensation from collecting in
the hopper during startup conditions in addition to
maintaining the hopper (and flyash) above the flue gas
acid dewpoint during normal operating conditions.
During the last decade many designs and operating
procedures have been tried to minimize or eliminate
hopper pluggage caused by compaction, agglomeration
and solidification. Many of the earlier designs were
based on solving the compaction problem only by
means of poke tubes and mechanical vibrators.
Fluidizing systems on the other hand tend to require
significant maintenance.Hopper heating was recognized
as the most practical method to prevent agglomeration
and solidification. Earlier designs using strip heaters,
MI cable and tubular heaters proved to be unreliable
because their constructions were prone to vibration
failure modes. In 1975 the first modular hopper heaters
became available. The heater was specifically designed
to provide a reliable source of hopper heating.
For this special application Thermon has developed
very rugged modular heaters. Instead of resistance
wire they contain a heating element stamped from a
high temperature alloy, Inconel 600, providing multiple
paths, eliminating series wire burnout which is so
typical for conventional systems. The Thermon Hopper
Heaters Type HT have been designed to withstand
harsh environments over 20 plus years of operating
life of the system.
Typical applications are:
• Parallel Circuit Heating Elements
• Reliable Connection Design
• Low Watt Density
• Vibration and Shock Resistance
• Rugged Construction
• Ease of Installation