Limits...
Automatic carbon dioxide-methane gas sensor based on the solubility of gases in water.

Cadena-Pereda RO, Rivera-Muñoz EM, Herrera-Ruiz G, Gomez-Melendez DJ, Anaya-Rivera EK - Sensors (Basel) (2012)

Bottom Line: Biogas methane content is a relevant variable in anaerobic digestion processing where knowledge of process kinetics or an early indicator of digester failure is needed.The device described in this work was used for determining the composition of binary mixtures, such as carbon dioxide-methane, in the range of 0-100%.The design and implementation of a digital signal processor and control system into a low-cost Field Programmable Gate Array (FPGA) platform has permitted the successful application of data acquisition, data distribution and digital data processing, making the construction of a standalone carbon dioxide-methane gas sensor possible.

View Article: PubMed Central - PubMed

Affiliation: Laboratorio de Biotrónica, Departamento de Investigación y Posgrado, Facultad de Ingeniería, Universidad Autónoma de Querétaro, Centro Universitario Cerro de las Campanas S/N, Querétaro 76010, Mexico. omar.cadena@upq.edu.mx

ABSTRACT
Biogas methane content is a relevant variable in anaerobic digestion processing where knowledge of process kinetics or an early indicator of digester failure is needed. The contribution of this work is the development of a novel, simple and low cost automatic carbon dioxide-methane gas sensor based on the solubility of gases in water as the precursor of a sensor for biogas quality monitoring. The device described in this work was used for determining the composition of binary mixtures, such as carbon dioxide-methane, in the range of 0-100%. The design and implementation of a digital signal processor and control system into a low-cost Field Programmable Gate Array (FPGA) platform has permitted the successful application of data acquisition, data distribution and digital data processing, making the construction of a standalone carbon dioxide-methane gas sensor possible.

Show MeSH

Related in: MedlinePlus

Schematic of the carbon dioxide-methane gas sensor. 1—container; 2—heat transfer fluid; 3—absorption liquid; 4 and 5—recirculation pump; 6—fan; 7—heat sink; 8—thermoelectric cell; 9—heat exchanger; 10—measurement cell; 11—flexible PVC reservoir; S1, S2 and S3—2-way solenoid valve; C—mini-compressor; PA—absolute pressure sensor; PG—gauge pressure sensor; T—temperature sensor.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3472854&req=5

f2-sensors-12-10742: Schematic of the carbon dioxide-methane gas sensor. 1—container; 2—heat transfer fluid; 3—absorption liquid; 4 and 5—recirculation pump; 6—fan; 7—heat sink; 8—thermoelectric cell; 9—heat exchanger; 10—measurement cell; 11—flexible PVC reservoir; S1, S2 and S3—2-way solenoid valve; C—mini-compressor; PA—absolute pressure sensor; PG—gauge pressure sensor; T—temperature sensor.

Mentions: To quantitatively determine the binary gas mixture, the carbon dioxide-methane gas sensor has to perform a three-stage cycle: sampling, adsorption and regeneration. In the sampling stage, the device takes in a predefined volume of gas in the measuring cell and calculates the number of moles of the binary gas mixture inside the measurement cell. In the next stage (absorption), the gas sensor removes the CO2 from the gaseous sample by movement-enhanced contact with a fixed quantity of absorption liquid. At the end of the absorption stage, the digital system calculates the remaining number of moles and displays the methane content percentage in the sample. In the third and last stage (regeneration), the gas sensor regenerates the CO2 saturated absorption liquid by movement-enhanced contact with air, releasing absorbed CO2 to the atmosphere. Figure 2 depicts the carbon dioxide-methane gas sensor, the constituent parts of which are a container (1), heat transfer fluid; (2), absorption liquid; (3), an absorption liquid recirculation pump; (4), a heat transfer fluid recirculation pump; (5), a fan; (6), a heat sink; (7), a thermoelectric module; (8), a heat exchanger; (9), a flexible measurement cell; (10), a flexible PVC reservoir; (11), an air intake 2-way solenoid valve (S1), a gaseous binary mixture sample intake 2-way solenoid valve (S2), a gas exhaust 2-way solenoid valve (S3), two mini compressors (C), an absolute pressure sensor (PA), a gauge pressure sensor (PG) used as level sensor, a temperature sensor (T) and electronics for control, data acquisition, data processing, data distribution, displaying and computer communication.


Automatic carbon dioxide-methane gas sensor based on the solubility of gases in water.

Cadena-Pereda RO, Rivera-Muñoz EM, Herrera-Ruiz G, Gomez-Melendez DJ, Anaya-Rivera EK - Sensors (Basel) (2012)

Schematic of the carbon dioxide-methane gas sensor. 1—container; 2—heat transfer fluid; 3—absorption liquid; 4 and 5—recirculation pump; 6—fan; 7—heat sink; 8—thermoelectric cell; 9—heat exchanger; 10—measurement cell; 11—flexible PVC reservoir; S1, S2 and S3—2-way solenoid valve; C—mini-compressor; PA—absolute pressure sensor; PG—gauge pressure sensor; T—temperature sensor.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3472854&req=5

f2-sensors-12-10742: Schematic of the carbon dioxide-methane gas sensor. 1—container; 2—heat transfer fluid; 3—absorption liquid; 4 and 5—recirculation pump; 6—fan; 7—heat sink; 8—thermoelectric cell; 9—heat exchanger; 10—measurement cell; 11—flexible PVC reservoir; S1, S2 and S3—2-way solenoid valve; C—mini-compressor; PA—absolute pressure sensor; PG—gauge pressure sensor; T—temperature sensor.
Mentions: To quantitatively determine the binary gas mixture, the carbon dioxide-methane gas sensor has to perform a three-stage cycle: sampling, adsorption and regeneration. In the sampling stage, the device takes in a predefined volume of gas in the measuring cell and calculates the number of moles of the binary gas mixture inside the measurement cell. In the next stage (absorption), the gas sensor removes the CO2 from the gaseous sample by movement-enhanced contact with a fixed quantity of absorption liquid. At the end of the absorption stage, the digital system calculates the remaining number of moles and displays the methane content percentage in the sample. In the third and last stage (regeneration), the gas sensor regenerates the CO2 saturated absorption liquid by movement-enhanced contact with air, releasing absorbed CO2 to the atmosphere. Figure 2 depicts the carbon dioxide-methane gas sensor, the constituent parts of which are a container (1), heat transfer fluid; (2), absorption liquid; (3), an absorption liquid recirculation pump; (4), a heat transfer fluid recirculation pump; (5), a fan; (6), a heat sink; (7), a thermoelectric module; (8), a heat exchanger; (9), a flexible measurement cell; (10), a flexible PVC reservoir; (11), an air intake 2-way solenoid valve (S1), a gaseous binary mixture sample intake 2-way solenoid valve (S2), a gas exhaust 2-way solenoid valve (S3), two mini compressors (C), an absolute pressure sensor (PA), a gauge pressure sensor (PG) used as level sensor, a temperature sensor (T) and electronics for control, data acquisition, data processing, data distribution, displaying and computer communication.

Bottom Line: Biogas methane content is a relevant variable in anaerobic digestion processing where knowledge of process kinetics or an early indicator of digester failure is needed.The device described in this work was used for determining the composition of binary mixtures, such as carbon dioxide-methane, in the range of 0-100%.The design and implementation of a digital signal processor and control system into a low-cost Field Programmable Gate Array (FPGA) platform has permitted the successful application of data acquisition, data distribution and digital data processing, making the construction of a standalone carbon dioxide-methane gas sensor possible.

View Article: PubMed Central - PubMed

Affiliation: Laboratorio de Biotrónica, Departamento de Investigación y Posgrado, Facultad de Ingeniería, Universidad Autónoma de Querétaro, Centro Universitario Cerro de las Campanas S/N, Querétaro 76010, Mexico. omar.cadena@upq.edu.mx

ABSTRACT
Biogas methane content is a relevant variable in anaerobic digestion processing where knowledge of process kinetics or an early indicator of digester failure is needed. The contribution of this work is the development of a novel, simple and low cost automatic carbon dioxide-methane gas sensor based on the solubility of gases in water as the precursor of a sensor for biogas quality monitoring. The device described in this work was used for determining the composition of binary mixtures, such as carbon dioxide-methane, in the range of 0-100%. The design and implementation of a digital signal processor and control system into a low-cost Field Programmable Gate Array (FPGA) platform has permitted the successful application of data acquisition, data distribution and digital data processing, making the construction of a standalone carbon dioxide-methane gas sensor possible.

Show MeSH
Related in: MedlinePlus