Oil and Gas Air Heaters

Abstract

Most conventional air heaters adopt indirect heat transfer, which uses combustion gases to indirectly heat fresh air by heating surfaces to generate hot air used for material drying and dehumidification. We call them indirect air heaters. However, they have a higher manufacturing cost and lower thermal efficiency, especially when high temperature air is needed. For this reason, a direct air heater applicable for or feed and industrial raw products is put forward, which has advantages such as less production cost, smaller dimensions and higher thermal efficiency. Their design, working principles, characteristics, structure and applications are presented in this article, and brief comparisons are made between the indirect and direct air heater. Finally, the relation of hot-air temperature, oil or gas consumption and fresh airflow is determined based on energy equilibrium.