Fuel gas determination using a MEMS gas analyser

Gas condition is of importance for operating industrial firing processes. Changing gas conditions, caused by a diversification of the natural gas purchase, affect combustion processes, the warmth brought into and subsequent production processes. Especially at sensitive thermal processing units a consequent adjustment of the burn attitudes is, with change of the natural gas condition, obligatory. The direct measurement of the gas condition ensures adjusting effects of variable gas conditions very fast and precisely. Thus consequent improvement advance the process and product quality. Currently available devices are mostly huge and expensive. Some inexpensive devices, which came to the market in the last years, measure only individual variables and are thereby not able to determine atypical gas compositions correctly. An answer to this problem enables the direct acquisition of clearly more gas constituents by using a MEMS analyser. Since large individual component determination of the natural gas components, disadvantages of existing systems will be avoid and the determination of a precise fuel value will be enabled. Core component of the system is a NIR-MEMS-spectrometer, which has been optimized for this purpose. The connection to the process is realized with a specific gas measuring cell. The realization of a practicable system require an exact adoption of the optical system according to efficient sample connection a high wavelength stability, which represents the condition for exact chemometric evaluation. Other challenges are MEMS design and packaging optimization regarding to vibration stability and thermal stress. The paper describes functional principle and characteristics of a novel MHMS-based gas analyser. Experimental results will demonstrate the sv stem performance.