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international conference on evolvable systems | 2004

The Development of the Vapor Phase Catalytic Ammonia Removal (VPCAR) Engineering Development Unit

Michael Flynn; John W. Fisher; Mark Kliss; Badawi W. Tleimat; Maher Tleimat; Gregory Quinn; James H. Fort; Tim Nalette; Gale Baker; Joseph Genovese

This paper presents the results of a program to develop the next generation Vapor Phase Catalytic Ammonia Removal (VPCAR) system. VPCAR is a spacecraft water recycling system designed by NASA and constructed by Water Reuse Technology Inc. The technology has been identified by NASA to be the next generation water recycling system [1]. It is designed specifically for a Mars transit vehicle mission. This paper provides a description of the process and an evaluation of the performance of the new system. The equivalent system mass (ESM) is calculated and compared to the existing state-of-the art. A description of the contracting mechanism used to construct the new system is also provided.


international conference on evolvable systems | 2007

Development Status of the Carbon Dioxide and Moisture Removal Amine Swing-Bed System (CAMRAS)

William Papale; Tim Nalette; Jeffrey J. Sweterlitsch

Under a cooperative agreement with NASA, Hamilton Sundstrand has successfully designed, fabricated, tested and delivered three, state-of-the-art, solid amine prototype systems capable of continuous CO2 and humidity removal from a closed, habitable atmosphere. Two prototype systems (CAMRAS #1 and #2) incorporated a linear spool valve design for process flow control through the sorbent beds, with the third system (CAMRAS #3) employing a rotary valve assembly that improves system fluid interfaces and regeneration capabilities. The operational performance of CAMRAS #1 and #2 has been validated in a relevant environment, through both simulated human metabolic loads in a closed chamber and through human subject testing in a closed environment. Performance testing at Hamilton Sundstrand on CAMRAS #3, which incorporates a new valve and modified canister design, showed similar CO2 and humidity removal performance as CAMRAS #1 and #2, demonstrating that the system form can be modified within certain bounds with little to no effect in system function or performance. Demonstration of solid amine based CO2 and humidity control is an important milestone in developing this technology for human spaceflight. The systems have low power requirements; with power for air flow and periodic valve actuation and indication the sole requirements. Each system occupies the same space as roughly four shuttle non-regenerative LiOH canisters, but have essentially indefinite CO2 removal endurance provided a regeneration pathway is available. Using the solid amine based systems to control cabin humidity also eliminates the latent heat burden on cabin thermal control systems and the need for gas/liquid phase separation in a low gravity environment, resulting in additional simplification of vehicle environmental control and life support system process requirements.


international conference on evolvable systems | 2005

Development of an Amine-based System for Combined Carbon Dioxide, Humidity, and Trace Contaminant Control

Tim Nalette; Julie Reiss; Thomas Filburn; Eric Mahan; Thomas A. P. Seery; Bob Weiss; Fred Smith; Jay L. Perry

A number of amine-based carbon dioxide (C02) removal systems have been developed for atmosphere revitalization in closed loop life support systems. Most recently, Hamilton Sundstrand developed an amine-based sorbent, designated SA9T, possessing approximately 2-fold greater capacity compared to previous formulations. This new formulation has demonstrated applicability for controlling C02 levels within vehicles and habitats as well as during extravehicular activity (EVA). System volume is competitive with existing technologies. Further enhancements in system performance can be realized by incorporating humidity and trace contaminant control functions within an amine-based atmosphere revitalization system. A 3-year effort to develop prototype hardware capable of removing C02, H20, and trace contaminants from a cabin atmosphere has been initiated. Progress pertaining to defining system requirements and identifying alternative amine formulations and substrates is presented.


international conference on evolvable systems | 2007

Testing of an Amine-Based Pressure-Swing System for Carbon Dioxide and Humidity Control

Amy Lin; Frederick Smith; Jeffrey J. Sweterlitsch; John Graf; Tim Nalette; William Papale; Melissa Campbell; Sao-Dung Lu

In a crewed spacecraft environment, atmospheric carbon dioxide (CO2) and moisture control are crucial. Hamilton Sundstrand has developed a stable and efficient amine-based CO2 and water vapor sorbent, SA9T, that is well suited for use in a spacecraft environment. The sorbent is efficiently packaged in pressure-swing regenerable beds that are thermally linked to improve removal efficiency and minimize vehicle thermal loads. Flows are all controlled with a single spool valve. This technology has been baselined for the new Orion spacecraft. However, more data was needed on the operational characteristics of the package in a simulated spacecraft environment. A unit was therefore tested with simulated metabolic loads in a closed chamber at Johnson Space Center during the last third of 2006. Those test results were reported in a 2007 ICES paper. A second test article was incorporated for a third phase of testing, and that test article was modified to allow pressurized gas purge regeneration on the launch pad in addition to the standard vacuum regeneration in space. Metabolic rates and chamber volumes were also adjusted to reflect current programmatic standards. The third phase of tests was performed during the spring and summer of 2007. Tests were run with a range of operating conditions, varying: cycle time, vacuum pressure (or purge gas flow rate), air flow rate, and crew activity levels. Results of this testing are presented and potential flight operational strategies discussed.


international conference on evolvable systems | 2005

Performance Testing of the Vapor Phase Catalytic Ammonia Removal Engineering Development Unit

Michael Flynn; Maher Tleimat; Tim Nalette; Gregory Quinn

This paper describes the results of acceptance testing of the Vapor Phase Catalytic Ammonia Removal (VPCAR) technology. The VPCAR technology is currently being developed by NASA as a Mars transit vehicle water recycling system. NASA has recently completed a grant to develop a next generation VPCAR system. This grant was peer reviewed and funded through the Advanced Life Support (ALS) National Research Announcement (NRA). The grant funded a contract with Water Reuse Technology Inc. to construct an engineering development unit. This contract concluded with the shipment of the final deliverable to NASA on 8/31/03. The objective of the acceptance testing was to characterize the performance of this new system. This paper presents the results of mass power, and volume measurements for the delivered system. In addition, product water purity analysis for a Mars transit mission and a planetary base wastewater ersatz are provided. Acoustic noise levels, interface specifications and system reliability results are also discussed. An assessment of the readiness of the technology for human testing and recommendations for future improvements are provided.


international conference on evolvable systems | 2005

Results of VPCAR Pilot Scale and System Level Tests for the Selective Oxidation of Ammonia to Nitrogen and Water

David T. Wickham; Jeffrey R. Engel; Jianhan Yu; Tim Nalette; Catherine Thibaud-Erkey; Gregory Quinn

The cost of delivering the payloads to space increases dramatically with distance and therefore missions to deep space place a strong emphasis on reducing launch weight and eliminating resupply requirements. The Vapor Phase Catalytic Ammonia Removal (VPCAR) system, which is being developed for water purification, is an example of this focus because it has no resupply requirements. A key step in the VPCAR system is the catalytic oxidation of ammonia and volatile hydrocarbons to benign compounds such as carbon dioxide, water, and nitrogen. Currently, platinum-based commercial oxidation catalysts are being used for these reactions. However, conventional platinum catalysts can convert ammonia (NH3) to NO and NO2 (collectively referred to as NOX), which are more hazardous than ammonia.


40th International Conference on Environmental Systems | 2010

Advanced Catalysts for the Ambient Temperature Oxidation of Carbon Monoxide and Formaldehyde

Tim Nalette; Christopher Eldridge; Ping Yu; Gokhan Alptekin; John Graf

The primary applications for ambient temperature carbon monoxide (CO) oxidation catalysts include emergency breathing masks and confined volume life support systems, such as those employed on the Shuttle. While Hopcalite is typically used in emergency breathing masks for terrestrial applications, in the 1970s, NASA selected a 2% platinum (Pt) on carbon for use on the Shuttle since it is more active and also more tolerant to water vapor. In the last 10-15 years there have been significant advances in ambient temperature CO oxidation catalysts. Langley Research Center developed a monolithic catalyst for ambient temperature CO oxidation operating under stoichiometric conditions for closed loop carbon dioxide (CO2) laser applications which is also advertised as having the potential to oxidize formaldehyde (HCHO) at ambient temperatures. In the last decade it has been discovered that appropriate sized nano-particles of gold are highly active for CO oxidation, even at sub-ambient temperatures, and as a result there has been a wealth of data reported in the literature relating to ambient/low temperature CO oxidation. In the shorter term missions where CO concentrations are typically controlled via ambient temperature oxidation catalysts, formaldehyde is also a contaminant of concern, and requires specially treated carbons such as Calgon Formasorb as untreated activated carbon has effectively no HCHO capacity. This paper examines the activity of some of the newer ambient temperature CO and formaldehyde (HCHO) oxidation catalysts, and measures the performance of the catalysts relative to the NASA baseline Ambient Temperature Catalytic Oxidizer (ATCO) catalyst at conditions of interest for closed loop trace contaminant control systems.


43rd International Conference on Environmental Systems | 2013

Investigation of the Potential Impact of Trace Contaminants on the Performance of the Sabatier Catalyst

Tim Nalette; Ping Yu; Jay L. Perry; Morgan B. Abney

The Carbon Dioxide Reduction Assembly (CRA) on the International Space Station (ISS) has been operational since 2010. The CRA uses a Sabatier reactor to produce water and methane by reaction of the metabolic carbon dioxide scrubbed from the cabin air and the hydrogen byproduct from the water electrolysis system used for metabolic oxygen generation. Incorporating the CRA into the overall atmosphere revitalization system has facilitated further life support system loop closure on the ISS reducing resupply logistics and thereby enhancing longer term missions. The CRA utilizes carbon dioxide which has been adsorbed in a 5A molecular sieve within the Carbon Dioxide Removal Assembly (CDRA). While the CDRA had a requirement to provide carbon dioxide at a purity of 98% with the balance being predominantly oxygen and nitrogen, there is a potential of compounds with molecular dimensions similar to, or less than CO2 to also be adsorbed – less than approximately 5 angstroms. In this fashion trace contaminants may be concentrated within the CDRA and subsequently desorbed with the carbon dioxide and passed to the CRA during operation. Currently, there is no provision to remove contaminants prior to entering the Sabatier catalyst bed. The risk associated with this is potential catalyst degradation due to trace organic contaminants in the CRA carbon dioxide feed acting as catalyst poisons. To better understand this risk, United Technologies Aerospace System (UTAS) has teamed with Marshall Space Flight Center (MSFC) to investigate the impact of various trace contaminants on the CRA catalyst performance at relative ISS cabin air concentrations and at about 200 to 400 times of ISS concentrations, representative of the potential concentrating effect of the CDRA molecular sieve and operation over a period of time. This paper summarizes the assessment of the initial results.


41st International Conference on Environmental Systems | 2011

CO Oxidation for Post-Fire Cleanup

Christopher Eldridge; Tim Nalette; John Graf; Gokhan Alptekin

Environmental control and life support systems require an approach to remove poisonous gases from the cabin in the event of a fire. As carbon monoxide is a major product of combustion, its immediate removal is required to protect the health of the crew. Advanced carbon monoxide catalysts have been evaluated and compared to the NASA baseline ATCO, developed in the late 1970’s, for post-fire cleanup in closed-volume habitats. The evaluation investigated the effect of space velocity and relative humidity on the performance of four advanced noble metal-based catalysts and ATCO at 1000 ppm carbon monoxide in air. The space velocity investigation concluded that Hamilton Sundstrand’s platinum-based catalyst maintained 100% conversion at the highest space velocity. Additional relative humidity testing is required to determine the relative activity of the Hamilton Sundstrand catalyst and a 3M gold catalyst as both maintained 100% conversion at the greatest space velocity evaluated.


international conference on evolvable systems | 2007

The ISS Water Processor Catalytic Reactor as a Post Processor for Advanced Water Reclamation Systems

Tim Nalette; Doug Snowdon; Karen D. Pickering; Michael R. Callahan

Advanced water processors being developed for NASA’s Exploration Initiative rely on phase change technologies and/or biological processes as the primary means of water reclamation. As a result of the phase change, volatile compounds will also be transported into the distillate product stream. The catalytic reactor assembly used in the International Space Station (ISS) water processor assembly, referred to as Volatile Removal Assembly (VRA), has demonstrated high efficiency oxidation of many of these volatile contaminants, such as low molecular weight alcohols and acetic acid, and is considered a viable post treatment system for all advanced water processors. To support this investigation, two ersatz solutions were defined to be used for further evaluation of the VRA. The first solution was developed as part of an internal research and development project at Hamilton Sundstrand (HS) and is based primarily on ISS experience related to the development of the VRA. The second ersatz solution was defined by NASA in support of a study contract to Hamilton Sundstrand to evaluate the VRA as a potential post processor for the Cascade Distillation system being developed by Honeywell. This second ersatz solution contains several low molecular weight alcohols, organic acids, and several inorganic species. A range of residence times, oxygen concentrations and operating temperatures have been studied with both ersatz solutions to provide addition performance capability of the VRA catalyst. Introduction The ISS Water Processor Assembly (WPA) was designed to produce potable water from various waste streams including humidity condensate, waste hygiene and urine distillate. The initial chemical treatment process is carbon adsorption and ion exchange to remove organic and ionic containments in the waste stream. Low molecular weight organic compounds which are highly soluble in water, such as alcohols, are not effectively adsorbed and are oxidized to organic acids and carbon dioxide by the a catalytic reactor referred to as the WPA catalytic reactor or Volatile Removal Assembly (VRA). Advanced water processors being developed for NASA’s Exploration Initiative rely on phase change and/or biological processes as the primary means of water treatment. The phase change technologies include air evaporation, rotary vacuum distillation processes such as vapor compression distillation (VCD), wiped film rotating disc (WFRD) and cascade rotary distillation (CRD). Depending on the operating conditions of these

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Jay L. Perry

Marshall Space Flight Center

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