Indirect temperatures measurement in the UCG process

The technology of the underground coal gasification (UCG) is still under development and provides alternative for conventional underground mining. UCG is the process, which can be attractive from environmental and economic aspect and is able to have a wide utilization in the future. This technology is less expensive than conventional mining. For research and good analyze of this process there was created the physical model of the gasifier, that simulate the conditions of the real coal-bed in geometric similarity. On created physical model was performed a several experiments represent a various underground conditions. In the gasification process the input is the coal (coal-bed) and oxidizer (mixture of the air and oxygen), which suitable combination provides the best conditions for gasification. One of the expected outputs from the coal gasification process is the high temperature in the coal-bed, which enable running of the chemical reaction needed for the syngas generation. The control of this temperature in the single places of the coal-bed would enable to control behavior of the chemical reactions so the burning queue proceeds. The measurement of the temperatures inside the coal-bed is still complicated because there is the high thermocouples mortality in aggressively hot environment. For this reason is needed to use mathematic - physical apparatus for indirect measurement of these temperatures. In this contribution is presented proposal of the indirect temperature measurement structure in the coal-bed that was verified in the laboratory conditions on the experimental gasifier.