Hot Air Generators

A hot air generator heats a moving air stream for drying, curing, seasoning and preheating duty — processes that need hot gas passing through or over a product rather than a heated surface in contact with it.

The specification decision that matters is direct versus indirect firing, and it is determined by the product, not by efficiency. Direct firing mixes combustion products into the process air. It is thermally efficient and simple, and it is entirely appropriate for aggregate drying, non-food materials and many industrial processes. Indirect firing passes combustion gas through a heat exchanger so that only clean, uncontaminated air reaches the product — which is what food, pharmaceutical, and fine chemical duty requires, and what any process sensitive to moisture or combustion by-products in the air stream requires.

Getting that choice wrong is expensive in both directions: an indirect unit where direct would serve adds capital cost and a heat exchanger to maintain, while a direct unit on a product that cannot tolerate flue gas contact is not correctable after installation.

Typical applications include spray and tray drying, timber and veneer seasoning, powder coating and paint curing, tea and spice drying, agricultural and food dehydration, and combustion air preheating. We supply both configurations with the fans, ducting, filtration and temperature controls that complete the system.