This compact and rugged binary gas analyzer is a non-negotiable tool for monitoring process gases

Process quality and safety are two common reasons for measuring the concentration of one gas in another. Designed with the demands of the chemical process industry and the hydrogen economy in mind, Panametrics’ newest gas analyzer, the XMTCpro is now available for measuring binary gas mixtures in concentrations from 0.1% to 100%. These binary mixtures include hydrogen, helium, methane, carbon dioxide and many other gases important for safety, quality and efficiency.

The XMTCpro builds on over three decades of experience and thousands of its predecessors (XMTC and TMO2-TC) installed and operating globally.

XMTCpro gas analyzer performance

XMTCpro bases its measurements on a gas’ thermal conductivity difference from the other gas in the mixture. Thermal conductivity measurements have several distinct advantages. In addition to their response to small process anomalies, there are no moving parts, and the sensor itself is wear-free, meaning nothing is consumed. This makes them ideal for long-term measurements, especially in environments where operating conditions place great demands – like temperature fluctuations, vibrations and other environmental stresses – on the material.

Using thermal conductivity as the differentiator allows for a continuous measurement with instantaneous and dynamic response. With an accuracy of +/- 2% of the total span, the XMTCpro provides the confidence needed to make process decisions. The sensor requires little maintenance and infrequent calibration.

Figure 1. The XMTCpro performs gas composition measurements continuously and accurately. Source: Panametrics

The XMTCpro provides the concentration information via one or more 4-20 mA analog outputs, or over Modbus RS232/RS485 digital protocol. This transmitter is available with or without a display. With features including the analog and digital outputs and alarm contact closures, as well as application-specific firmware features, the XMTCpro is a true analyzer.

It is available in an explosion-proof package, meeting the installation requirements of the chemical process and refining industries. The analyzer can also be chosen with the SIL 2 option for implementation in critical safety applications. The standard XMTCpro shares the same sensor and electronics as the SIL 2 version, ensuring the highest level of confidence and quality.

XMTCpro in the field

There are numerous applications in which binary gas measurements are made. The purity of process gases must be monitored to verify separation processes, limit side reactions and enhance process safety.

Hydrogen economy and energy transmission

Electrolyzers split water into oxygen and hydrogen. Both are high value gases and have their own uses, with the hydrogen having the higher value today as a clean fuel source. However, under certain circumstances, the oxygen and hydrogen can cross-over at the membrane and mix. This is both a contamination issue and also a major safety hazard, as the presence of one in the other forms an explosive mixture. The analyzer quickly and reliably detects the increased presence of the hydrogen in the oxygen stream, allowing the operator to take appropriate action.

Power generation and hydrogen cooling

For large gas turbines, hydrogen is used to remove heat from the rotating equipment. Hydrogen is preferred over other gases due to its high thermal conductivity and its low density. This allows heat to be removed at a quicker rate, all while providing less resistance for the turbine to spin through. However, hydrogen is flammable and is still a safety concern. Air can leak into the system. Further, during start-up and shut-down, carbon dioxide flushes out the gas turbine so that air and hydrogen never mix. Three-range firmware is available to allow the operator to see the air-carbon dioxide mix, carbon dioxide-hydrogen mix, and hydrogen-air mix concentrations, giving this operator three binary gas analyzers in one transmitter.

Chemical processing and refining

Chemical and refining operations have many gas applications that must be tightly controlled for safety and quality reasons. These include hydrogen in ammonia manufacturing; hydrogen concentration in hydrogen-recycle streams on a continuous catalytic reformer; and hydrogen-methane mixtures in various process. These are just a few applications where a binary gas analyzer shines.

Biogas and landfill gas upgrading to biomethane

Gone are the days where natural waste gases are vented or flared to the atmosphere. Animal and plant waste decompose and form natural gas and carbon dioxide. The same is true for waste in landfills. These gases are separated using membrane technology and the water vapor is removed. The natural gas can be used locally or lifted into the grid. The carbon dioxide can also be sold or can be transported and sequestered. The XMTCpro uses the differences in these gases’ thermal conductivity to provide continuous measurements on either side of the membrane, a distinct advantage over far more expensive gas chromatographs.

Heat treatment in metals processing

There are many metal heat-treating processes including brazing, annealing, sintering and nitriding. In many of these processes, disassociated ammonia with or without the addition of hydrogen or nitrogen is fed into a typically high-temperature environment where the metal or parts are treated. The significant difference in thermal conductivity allows the XMTCpro to monitor the gas mixture for excursions, ensuring process quality.

Figure 2. XMTCpro used in a sample conditioning system. Source: Panametrics

The Panametrics advantage

Continuous and reliable gas analysis is essential in process applications, ensuring the quality of the final product in a safe environment. Panametrics' next generation gas analyzer, the XMTCpro, provides the necessary measurements that these industries have come to expect.