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Hollow fiber membranes aerate wastewater without bubble formation by separating the liquid and gases phases with a semi-permeable membrane. These membranes have shown to successfully create aerobic conditions within a biological reactor. This research investigated the effect of long term usage and biofilm growth on membrane's ability to transfer oxygen to solution. Results show that oxygen transfer across the membrane decreased significantly compared to unused membranes in areas of high biofilm growth while low biofilm growth showed only slight decreases.

Microbial control in closed environmental systems, such as those of spacecraft or proposed base missions is typically limited to disinfection in the potable water system by a strong chemical agent such as iodine or chlorine. However, biofilm growth in the environmental system tubing threatens both the sterility of the potable water distribution as well as operational problems with wastewater systems. In terrestrial systems, biofilm has been recognized for its difficulty to control and eliminate as well as resulting operational problems. In order to maintain a potable water source for crew members as well as preventing operational problems in non-sterile systems, biofilm needs to be considered during system design. While biofilm controls can limit biofilm buildup, they are typically disruptive and cannot completely eliminate biofilm. Selenium coatings have shown to prevent initial biofilm attachment as well as limit attached growth on a variety of materials.

Long-duration space travel will require improvements in exercise countermeasures so that astronauts are able to maintain cardiovascular fitness, bone mass and the ability to perform coordinated movements in a terrestrial environment following extended periods of “near weightlessness” encountered during transit to and/or obit of the Moon, Mars, and Earth. In such gravitational transitions feedback and feedforward postural control strategies must be recalibrated to ensure optimal locomotion performance. Current data suggests that specific, short duration musculoskeletal loading, following running in simulated Martian gravity using a vertical suspension type simulator, reduces the time required for re-adapting to steady-state performance of the postural control system during a novel, treadmill based precision stepping task. Possible enhancements to the current exercise countermeasures program are suggested.

The objective of this study was to evaluate the treatment efficiency and reliability of a small-scale (1/20th) replica of the JSC biological treatment system over an extended period of time (18 months of operation). The two biological reactor components were an anaerobic packed bed for denitrification and an aerobic tubular reactor for nitrification. A recycle line (20X) linked the two biological reactors. Effectiveness of the biological system to treat a waste stream (1 L/day) containing water, urine, and soap (Igepon T42) was quantified by monitoring total nitrogen and organic carbon. Distribution of nitrogen in the effluent was measured and consisted of ammonium, nitrite, and nitrate. Daily concentrations of total nitrogen in the influent varied greatly. The system achieved 50% removal of total nitrogen and 80% removal of the influent organic carbon. The results indicate improved treatment effectiveness and resiliency with time.

This research compared the nutrient content of the Biological Water Processor (BWP) effluent at JSC with acceptable nutrient ranges for general hydroponic NFT-solutions. Evaluated nutrient-components were NO3-N, P, K, Ca, Mg, Fe, Mn, Zn, B, Cu and Mo. Compared to Cooper's and Molyneaux's solution (Jones, 1997) BWP-nutrient concentrations were low for Ca, Mg, Fe and B. Compared to the NFT-solution used at KSC (Wheeler et al., 1997), the BWP-effluent showed higher contents of P, K, Zn, Cu and Mo and lower contents of N, Ca, Mg, Fe and B. This indicates that the BWP-effluent could support NFT-plant production.

The Advanced Integration Matrix (AIM) project at the Johnson Space Center (JSC) was chartered to study and solve systems-level integration issues for exploration missions. One of the first issues identified was an inability to conduct trade studies on control system architectures due to the absence of mature evaluation criteria. Such architectures are necessary to enable integration of regenerative life support systems. A team was formed to address issues concerning software and hardware architectures and system controls.. The team has investigated what is required to integrate controls for the types of non-linear dynamic systems encountered in advanced life support. To this end, a water processing bioreactor testbed is being developed which will enable prototyping and testing of integration strategies and technologies.

This research is based on the hypothesis that recycling biofilm can provide the required carbon to increase biological denitrification of the carbon limited early planetary base wastewater. Recycling biofilm may offer significant advantages including a reduction in solid waste from biological wastewater processors, increased N2 return to cabin air, a reduction in TDS loading to the RO system, and increased alkalinity to drive further nitrification. The results of the study indicate that denitrification rate did increase due to the addition of lysed biofilm derived from the nitrification reactor. However, there was a simultaneous large release of additional ammonium. Further work will be required to understand the magnitude of the ammonium release and overall benefits of the process.

NASA's mission statement includes the protection of the home planet and a goal to inspire the next generation of explorers. NASA's current vision also includes human exploration of the Moon and Mars. Typically, residents of low-income communities are not directly involved in the space exploration process. Parents of children in low-income communities are inclined to be more interested in the educational components of NASA's activities rather than the technological accomplishments. This paper describes the approach taken to start and support a space and science club in a colonia near the U.S. - Mexico border in South Texas. The club provided a new organizational structure for linking NASA's goals with a low-income community. The structure of the club evolved over the course of three years to reflect the interests and resources of the youth that lived in the colonia.

The concept that plants and humans in a living system are mutually beneficial was communicated to 2nd - 12th grade students in science educational and outreach programs at Texas Tech University's Center for Space Science. Students traveled to the TTU horticulture greenhouse for a live program, which focused on research in the Engineering Development Unit. The research is funded by NASA's Advanced Life Support. During the program students were presented with the science of growing plants, how plants benefit humans in space, and baseline science vocabulary. A survey instrument was developed to assess student level of understanding of sciences, and their comprehension of living cycles, which work together to support manned space missions. The survey consisted of multiple-choice questions covering topics presented during the program. Likert questions were used to assess student's desire to travel in space, be an astronaut or a scientist, and their enjoyment of science and growing plants.

From 1997 to 2001, the third author worked with a team of engineers at JSC to develop the requirements and basic design for the Bioregenerative Planetary Life Support Systems Test Complex, or BIO-Plex. Under the Advanced Integration Matrix (AIM) Project, this earlier effort is extended to an investigation of methods and approaches for Advanced Systems Integration and Control. The intent is to understand and validate the use of software as an integrating function for complex heterogeneous systems, particularly for Advanced Life Support (ALS), in the context of support of mission operations. Preliminary investigations undertaken in the summer of 2004 indicate that integration of controls for the type of dynamic, non-linear, closed-loop biological systems under investigation for ALS systems require a different systems engineering approach than that required for traditional avionics systems.

Texas colonias are unincorporated subdivisions characterized by inadequate water and wastewater infrastructure, inadequate drainage and road infrastructure, substandard housing, and poverty. Since 1989 the Texas Legislature has implemented policies to halt further development of colonias and to address water and wastewater infrastructure needs in existing and new colonias along the border with Mexico. Government programs and non-government and private organization projects aim to address these infrastructure needs. Texas Tech University's Water Resources Center demonstrated the use of alternative on-site wastewater treatment in the Green Valley Farms colonia, San Benito, Texas. The work in Green Valley Farms was a component of a NASA-funded project entitled “Evaluation of NASA's Advanced Life Support Integrated Water Recovery System for Non-Optimal Conditions and Terrestrial Applications.” Two households within the colonia were demonstration sites for the constructed wetlands.

The objective of this study was to investigate the potential of membrane-aerated bioreactors as long term microgravity compatible nitrifying biological water processors (BWP). A small-scale (1/20th) replica of the water recovery system (WRS) at JSC has been operated and extensively analyzed at Texas Tech University (TTU) for the last 3 years. The current nitrifying tubular reactor at JSC and TTU has experienced difficulty in maintaining efficiency and low maintenance. In an attempt to increase the efficiency of the biological portion of the WRS, a membrane-aerated bioreactor (MABR) was constructed and operated using the same parameters as the TTU-WRS in August 2003. The MABR is downstream of an anaerobic packed bed and is designed to promote nitrification (NH4 → NOx). The MABR achieved a percent nitrification of 61% and 55% for recycle ratios of 10 and 20, respectively.

Simulated wastewater, known as early surface mission wastewater, treated in previous experiments at JSC and TTU included urinal flush water, shower water, humidity condensate, oral hygiene water, and hand wash water. In reality, there is a difference between the early surface mission wastewater and the International Space Station wastewater. The ISS does not have a shower or hand wash, which contributes approximately 59 percent of the make-up water treated. The average influent ammonia concentration in the simulated wastewater treated by the TTU water reclamation system frequently exceeds 500 mg/L. Removal of the shower make-up water in simulated wastewater will result in a significant increase in the ammonia concentration, resulting in higher influent pH values and ammonia concentrations that may be inhibitory. Biological treatment technologies have suitably treated the diluted waste stream but a more concentrated waste stream may present a greater challenge.