Centro de Investigação de Montanha (CIMO), ESA, Instituto Politécnico de Bragança, 5300-253 Bragança, Portugal.
Department of Biological and Environmental Sciences, Federal Technological University of Paraná, Medianeira 85884-000, Brazil.
Sensors (Basel). 2021 Nov 10;21(22):7456. doi: 10.3390/s21227456.
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 (SnO). 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.
甲烷是一种主要的温室气体和对流层臭氧的前体，其大部分来源都与人为活动有关。甲烷的来源众所周知，其监测通常涉及使用昂贵且运营成本高的气体分析仪。许多研究都探讨了使用低成本气体传感器来替代测量甲烷浓度；然而，这仍然是一个需要进一步发展的领域，以确保可靠的测量。在这项工作中，开发了一种用于测量低浓度范围内甲烷的低成本平台，并在两个不同的环境中使用，以连续评估和改进其性能。甲烷传感器是 Figaro TGS2600，一种基于二氧化锡（SnO）的金属氧化物半导体（MOS）。在第一阶段，监测平台在经过多点校准后，应用于一个小型反刍动物畜舍。在第二阶段，该系统与多气体分析仪（Gasera One Pulse）一起用于污水处理厂。低成本传感器的校准基于两个设备读数之间的关系。还测量了温度和相对湿度，以进行校正，以最大程度地减少这些变量对传感器信号的影响，并使用主动通风系统来改善传感器的性能。该系统被证明能够在两个地方以可靠的时空模式测量低浓度的甲烷。在 WWTP 中，两个测量系统之间也可以明显看出非常相似的行为。总的来说，低成本系统在多种环境条件下表现良好，至少作为一种筛选监测系统，它是一个很好的替代方案。
