CH4 Sensor Research Articles

MICROCONTROLLER BASED HYDROGEN SULFIDE (H2S) MONITORING IN BIOGAS SYSTEM

Energy issue, particularly related to fossil fuel, is one the main issues today. Biogas is a new and renewable energy issued in National Research Agenda (ARN) 2010-2014 to overcome the energy crisis problem. A so called purification process is used to remove contaminants in biogas, including H2S in order to improve the standard requirement of biogas application. In this research, H2S concentration in biogas system is measured and monitored by H2S monitoring system.The hardware system comprises of piping and microcontroller AVR 8535 systems while the software system comprises of codes written in Delphi 7.0 and Code Vision AVR Eval. The result of the system is displayed on LCD or computer to enable the monitoring process by operator. The monitoring of H2S sensor responses will be carried out for recycled BFA size of 60+100 mesh and -200 mesh.Experiment has been conducted for sensor warming up time and response time for H2S and CH4 sensor, calibration process for H2S sensor and filter column. Based on sensor calibration experiment, transfer function of TGS825 sensor from calibration is y = 0.0203x + 27.153. The best adsorption model which represents BFA adsorption of biogas from tofu waste in the research is Thomas model.

Development of CH4 Sensor Using MEMS Technology for Battery Operated Town Gas Leak Detector

Development of CH₄ Sensor Using MEMS Technology for Battery Operated Town Gas Leak Detector

Methane gas-sensing and catalytic oxidation activity of SnO2–In2O3 nanocomposites incorporating TiO2

The InO1.5–SnO2 nanocomposites incorporating TiO2 were synthesized by a controlled co-precipitation method as sensing materials of a novel semiconductor CH4 sensor. Through manipulating the total salt concentration, cation ratio, precipitation pH, aging time and calcination temperature, the nanocrystalline composites were successfully derived with chemical homogeneity and superior thermal stability compared to tin oxide. The gas-sensing and catalytic activity for methane oxidation were examined in a micro fixed bed reaction system. The experimental results showed that the nanocomposites exhibited high gas-sensing and catalytic activity, and these performances depended on composition of composites, calcination temperature of precursors and sensor operating temperature. It was found that the sensing behavior was straightforwardly related to the catalytic activity. The sensing and catalytic activity was greatly enhanced by the introduction of metal elements or oxide surface coatings. To guide for the search of better sensor materials or suitable additives, it is necessary to understand the sensing mechanism of the semiconductor oxide gas sensors by temperature-programmed desorption (TPD) study and X-ray photoelectron spectroscopic (XPS) analysis.