A case-study of microsensors for landfill air-pollution monitoring applications

• Portable sensor-system with commercial MOX gas sensors for air quality measurements.
• Different measurement environments: landfill, laboratory.
• Sensor-array response to odour monitoring assessed in landfill.
• Sensor-array response to landfill gas was discussed.
• Sensor-array response to CH4 and NMHC emitted by landfill versus referenced analyzer.

The purpose of this paper is to present a research study on application of low-cost solid-state gas microsensors for odour control and air-pollution monitoring in a landfill. The method introduces microsensors based on commercial devices of n-type metal oxides for cost-effective and real-time monitoring. This research provides a comparative study and assessment of the sensor response for odour detection and potential continuous monitoring of methane (CH4) and Non-Methanic Hydro-Carbons (NMHC) in a landfill. This leads to an insight into low-cost gas sensing capability for practical applications. The environmental measurements have been performed by a sensor-array with multiple sensing elements for high sensitivity and broad selectivity detection. This sensor technology may be useful for the development of a portable, compact, wireless and cost-effective system for gas monitoring applications and industrial process control. The results are discussed as the outcome of an experimental work carried in field at a landfill and demonstrate the efficiency of the low-cost chemo-resistors array for odour sensing and environmental monitoring. Additional long-term investigations need to address some drawbacks on sensors stability and cross-sensitivity.