MiniTOCA Facilitates Automated Water Analysis
Instrumentation
MiniTOCA Facilitates Automated Water Analysis (MSC-TOPS-142)
Provides real-time remote total organic carbon analysis of water samples
Overview
Seizing upon the success of the Total Organic Carbon Analyzer (TOCA) operating aboard the ISS, innovators working for NASA Johnson Space Center (JSC) have revamped a potable water monitoring technology for long-duration crewed space missions into a smaller, lighter package called “MiniTOCA”. Total Organic Carbon (TOC) concentration can indicate the presence of organic compounds in a water sample such as that from decaying plants and bacteria along with hazardous chemicals.
Currently, commercial TOC analyzers fail to meet the requirements set for deep space exploration typically due to gravity dependence, hazardous acid needed for inorganic carbon determination, and hazardous chemical or combustion reactor usage needed for oxidation. Ideally, exploration spacecraft instrumentation, including water monitoring technology, would not need resupply chemicals, would possess a low mass/volume archi-tecture, and would enable reliable online sensors to furnish real-time water quality data.
The MiniTOCA reflects success in achieving these goals along with providing additional tunability to fit specific mission requirements including mass, volume, crew time, and resupply needs. The MiniTOCA is at a technology readiness level (TRL) 7 (System prototype demon-stration in an operational environment) and is now available for patent licensing. Please note that NASA does not manufacture products itself for commercial sale.
The Technology
Environmental Control and Life Support Systems (ECLSS) used for extended space missions must recover and process wastewater to provide potable water for crew consumption and oxygen generation. Exploration mission spacecraft will have a smaller crew than the ISS, meaning demands would typically be less than what full-featured commercial TOC analyzers are designed to provide. Current analyzer technology also has limitations and uncertainties for spaceflight integration, such as part traceability, reliability, material properties for flammability or off-gassing, software and interface that are inconsis-tent with spaceflight needs, human factors, and structural reliability.
The MiniTOCA provides a compact solution to the performance demands of onboard water quality analysis for crewed exploration missions through a unique core technology process that facilitates the detection of trace organic compounds in a water sample. It utilizes an ultra-violet oxidation method to activate the dissolved oxygen in the water which results in oxidation of the organic chemicals into carbon dioxide. The carbon dioxide is then measured by a Miniature Tunable Laser Spectrometer (MTLS) by sweeping the carbon dioxide out of the water in a gas / liquid separator using nitrogen gas.
This novel process allows for small system sample volumes, small overall size/mass, zero consumables, low average power con-sumption (less than 60W), projected long-life (~10 years), and reliable analytical performance – all addressing critical performance gaps within the current TOC analyzer industry. Lab and environmental testing demonstrated that the MiniTOCA’s architecture is both feasible and is excellent in performance.
Potential commercial applications for the MiniTOCA include, but are not limited to, ultra-pure water (UPW) systems; remote, mobile, and distributed environmental water quality monitoring; and specialized industrial process control. Technologies comprising the device lend themselves to miniaturization and are forward leaning in exploration applications. The MiniTOCA is scheduled to be flown and imple-mented aboard the ISS in late 2025.
Benefits
- Provides real-time automated analysis of total organic carbon in water samples
- Furnishes data through incorporation of online remote sensing
- Provides oxidation without hazardous chemicals
- Performs at low TOC concentrations due to instrument sensitivity
- Fits into small form factors
- Operates with zero consumables
- Consumes low amounts of power (
- Extended lifespan (estimated lifespan is 10-years with maintenance needs potentially at less than 1 hour per year of crew time including calibration)
- Utilizes small sample volumes
Applications
- Ultra-Pure Water (UPW) Systems such as those used in semiconductor manufacturing, pharmaceutical and biotech, and power generation
- Remote, Mobile, and Distributed Environmental Water Quality Monitoring such as autonomous water monitoring platforms, distributed industrial wastewater monitoring, field deployment, and emergency response situations
- Specialized Industrial Process Control such as closed-loop process water recycling, food and beverage processing, bioreactor and fermentation monitoring
Technology Details
Instrumentation
MSC-TOPS-142
MSC-27904-1
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