A. Introduction

Catalytic heating devices or, generally, catalytic heaters, are radiant heating devices that use the catalytic combustion of hydrocarbons as heat source. Air and fuel are fed to a catalytic bed inside the heater, typically in countercurrent flow (counter-diffusive reactors), where they react and release heat and reaction products (hot fumes, mainly carbon dioxide and water). The heat produced by the catalytic combustion is transferred to the heated surface by directed (or redirected) radiation. Heat transfer by convection is typically considered negligible in the radiant section of the heater. However, some designs include convective sections that act as economizers to extract part of the sensible heat in the hot fumes [e.g., invention in Kulikov et al. (2014)]. The catalytic combustion (Trimm, 1983) is flameless, takes place at much lower temperatures than conventional combustion, and is more efficient. As a result, catalytic heaters are presented as reliable, efficient, and safe pieces of equipment for industrial and domestic applications.

This chapter is organized as follows. First, a summary of the main advantages, disadvantages, and applications of catalytic heaters is provided in Section B. A description of the components typically present in catalytic heaters is presented in Section C. Finally, several types/configurations of industrial catalytic heaters are described in Section D. A future extension of this chapter will deal with the basic design and sizing of catalytic heaters.

B. Advantages, Disadvantages, and Applications

Catalytic heating can be categorized as radiant heating. Conventional radiant heaters produce heat from electricity or conventional (uncontrolled) combustion. Catalytic heating presents several advantages with respect to conventional heating methods (Kulikov et al., 2014; Porsin et al., 2015; Ismagilov and Kerzhentsev, 1990; Lukyanov et al., 2003; Bruest Catalytic Heaters, 2015):