Portable, low power soil gas analyzer

There is a need for soil gas analyzers to characterize subsurface biogeochemical processes by measuring simultaneously multiple gases that are signatures for specific processes. Instruments should be significantly more portable and require less power than what is currently available. The analyzers need to be suitable for field work and laboratory studies. How This Problem is Being Addressed: Rugged, compact, low power, and reasonably priced instruments will be developed for simultaneous measurements of at least six key gases (carbon dioxide, methane, water vapor, oxygen, nitrogen, and nitrous oxide). Commercial instruments will be fully automated and operate without requiring consumable supplies. What is to be done in Phase II? A prototype multiple gas analyzer will be developed and field tested in Phase II. Field tests will be performed at DOE’s East River site. Evaluations will emphasize long term stability. Carbon dioxide, methane, water vapor, oxygen, and nitrogen will be measured simultaneously using one optical method. Nitrous oxide and carbon monoxide will be measured using a different optical technique. Commercial Applications: Direct measurement of multiple soil gases including nitrogen now requires multiple analyzers. Commercial gas analyzers will be suitable for field studies including long-term continuous monitoring of nitrogen-cycle and carbon-cycle processes. Specific end user applications include characterizing biologic respiration, CH4 oxidation, dissolution of CO2, reaction with soil carbonate, and atmospheric mixing. Instruments will be easily transported for field work, fully automated, self-calibrating, and will operate at low power.