Indirect Air Heater Overview

For original blog, visit: http://www.stelterbrinck.com/blog/indirect-air-heater/

Indirect air heaters are used as the hot air source to dry chemically sensitive products. In order to

effectively heat the end product and avoid contamination by the products of combustion, indirect fired

air heaters use a heat medium, such as a heat exchanger, to transfer heat to the end product. By using

heat exchangers, indirect fired air heaters can provide relatively high thermal efficiencies. Stelter &

Brinck’s Indirect Air Heaters are 72-90% thermally efficient, depending upon the application.

These process heaters are mainly used in food, chemicals, pharmaceuticals, and other product

manufacturing where the taste, look or feel of the end product may be altered by combustion flue gases

or particulates. For example, in cigarette manufacturing, the paper must be flavored using tobacco

extracts or else the taste will be inferior. However, before being applied to cigarette paper, the extracts

must first be spray dried to a powder form. In order to create the “smooth” smoke taste that tobacco is

known for, the spray driers use indirect fired process air heaters as their heat source. Because indirect

fired air heaters do not contaminate the airstream with the by-products of combustion the tobacco

flavor remains “pure”.