Infrared heating system

Infrared heating systems are used for crosslinking during the application of surface finishes to profiles, such as flock finishes. Silicone profiles are also produced using high temperature infrared systems. 

Infrared heating systems are classified as open type, tunnel type, and closed type. The open type is the simplest system to complement, but its energy loss is the largest. The tunnel type installs infrared sources in tunnel dryers and is operated continuously. The closed type is operated in a closed room, and usually has the highest energy efficiency, as listed in Table 35.2, because the materials are not only heated by direct irradiation of radiative energy from infrared sources but also by the convective heating of air heated by the sources. 

It is well known that y or X photons have energies suitable for excitation of inner electrons. We can use ultraviolet and visible radiation to initiate chemical reactions (photochemistry). Infrared radiation excites bond vibrations only whereas hyperfrequencies excite molecular rotation. In Tab. 1.1 the energies associated with chemical bonds and Brownian motion are compared with the microwave photon corresponding to the frequency used in microwave heating systems such as domestic and industrial ovens (2.45 GHz, 12.22 cm). 

In the process, the TDU heats contaminant molecules above their boiling points to desorb the contaminants into the vapor phase in an oxygen-deficient environment, thus preventing oxidization of the contaminants. The volatilized contaminants and the moisture from the soil are condensed and collected within the system. The process is then controlled by using infrared heating and an alloy belt feed system within the TDU. 

Another style of furnace system, provided by Ulvac/Sinku-Rico Inc. [11], is an infrared heating furnace (Figure 2.9). This... 

Thermal treatment processes use energy to destroy or decontaminate waste. These technologies include low or high energy thermal processes. Several types of thermal processes include flame combustion, fluidized bed combustion, infrared incineration, pyrolysis and plasma heat systems. 

A compound of tellurium, cadmium, and mercury is also used in infrared detection systems. Infrared radiation is heat. It can be made visible with special glass. Some satellites orbiting Earth study forests, crops, and other plant life by measuring the infrared radiation they give off... 

The transition metal ion-containing films were prepared carefully by ion-exchange as described elsewhere (10-16). These films were mounted in appropriate stainless steel or pyrex glass reactors/spectroscopic cells. Both reactors, described in detail elsewhere, had infrared (KBr) or uv-vis (quartz) transmitting windows for spectroscopic studies. They were equipped with vacuum valves for evacuation and gas admission, a heating system and a temperature monitor. 

Fig. 4.3 Automatic system for the determination of humidity in solid samples (Mettler IR LP 16 desiccator. (1) Pair of dual infrared heating bars (2) two thermal probes (3) rising humidity (4) infrared radiation (5) air-cut (6) sample scale (7) air gates (8) outside air (9) input keyboard (10) high-precision balance. (Courtesy of Mettler).

The Active Photothermal Camera (APC) analyses propagation of heat produced by a laser aimed at the surface of the part being inspected. The analysis is performed by an infrared detection system that can pinpoint a disturbance in the heat transfer field such as that caused by a defect, whether emerging or subsurface. 

Variable-temperature cells, which are controlled to 0.1°C in the range —180 to 250°C, may be used in infrared spectrometers. An electrical heating system is used for temperatures above ambient, and liquid nitrogen with a heater for low temperamres. These cells can be used to study phase transitions and the kinetics of reactions. As well as transmission temperature cells, variable-temperature ATR cells and temperamre cells for microsampling are available. 

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