Abstract
Methane is a major greenhouse gas and a precursor of tropospheric ozone, and most of its sources are linked to anthropogenic activities. The sources of methane are well known and its monitoring generally involves the use of expensive gas analyzers with high operating costs. Many studies have investigated the use of low-cost gas sensors as an alternative for measuring methane concentrations; however, it is still an area that needs further development to ensure reliable measurements. In this work a low-cost platform for measuring methane within a low concentration range was developed and used in two distinct environments to continuously assess and improve its performance. The methane sensor was the Figaro TGS2600, a metal oxide semiconductor (MOS) based on tin dioxide (SnO2). In a first stage, the monitoring platform was applied in a small ruminant barn after undergoing a multi-point calibration. In a second stage, the system was used in a wastewater treatment plant together with a multi-gas analyzer (Gasera One Pulse). The calibration of low-cost sensor was based on the relation of the readings of the two devices. Temperature and relative humidity were also measured to perform corrections to minimize the effects of these variables on the sensor signal and an active ventilation system was used to improve the performance of the sensor. The system proved to be able to measure low methane concentrations following reliable spatial and temporal patterns in both places. A very similar behavior between both measuring systems was also well noticeable at WWTP. In general, the low-cost system presented good performance under several environmental conditions, showing itself to be a good alternative, at least as a screening monitoring system.
Highlights
Over the last two hundred years, the rapid increase in Earth’s average surface temperature has been caused mainly by human activities, due to the rise in atmospheric concentrations of the so-called greenhouse gases, of which carbon dioxide (CO2 ), water vapor (H2 O), methane (CH4 ) and nitrous oxide (N2 O) are the most impactful [1]
Between the years 1750 and 2011, the average global concentration of methane increased by a factor of 2.5, raising from 722 ± 25 ppb to 1803 ± 4 ppb, mainly due to anthropogenic activities related to cattle raising; the expansion of rice crops; gaseous emissions from landfills; and the extraction, production, and use of fossil fuels
This curve stablishes the relationship between RS /R0 values and the methane concentrations generated by the calibration system
Summary
Over the last two hundred years, the rapid increase in Earth’s average surface temperature has been caused mainly by human activities, due to the rise in atmospheric concentrations of the so-called greenhouse gases, of which carbon dioxide (CO2 ), water vapor (H2 O), methane (CH4 ) and nitrous oxide (N2 O) are the most impactful [1]. The excess of these gases increases the infrared radiation retained in the atmosphere, amplifying the greenhouse effect and raising the Earth’s surface average temperature [1,2]. Tools for monitoring methane are essential for emissions control, air quality assessment and health protection
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call