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Waste management is a vital function of spacecraft life support systems as it is necessary to meet crew health and safety and quality of life requirements. Depending on the specific mission requirements, waste management operations can include waste collection, segregation, containment, processing, storage and disposal. For the Crew Exploration Vehicle (CEV), addressing volume and mass constraints is paramount. Reducing the volume of trash prior to storage is a viable means to recover habitable volume, and is therefore a particularly desirable waste management function to implement in the CEV, and potentially in other spacecraft as well. Research is currently being performed at NASA Ames Research Center to develop waste compaction systems that can provide both volume and mass savings for the CEV and other missions.

Distant and/or long-term missions, particularly Mars and lunar bases, will require a high degree of regenerative systems utilization. Bio-regenerative systems inherently lend themselves to integrative application, and can serve multiple processing functions in Advanced Life Support (ALS) systems. Striving for maximal use of bio-regenerative systems can reveal possibilities and relationships difficult to conceptualize within the context of a “unit process” methodology common to physico-chemical (P/C) systems. The required regenerative functions of biomass production and solid, liquid, and air processing are discussed, and a potential integrated ALS system scenario including “soil'based” plant production is developed to illustrate potential ramifications of biological (and P/C) system integration.

The use of biofilters for the control of air contaminants in Advanced Life Support (ALS) systems is currently being investigated by the Waste Processing and Resource Recovery research team of the New Jersey - NSCORT (NASA Specialized Center of Research and Training). Ammonia (NH3) was selected as a test air contaminant as it presents special challenges to the sustained operation of a biofilter. Ammonia loading to the ALS atmosphere will likely be from waste treatment (biological treatment of human, plant and food wastes) and food processing operations. This NH3 has the potential of causing adverse effects on plant growth and humans.

A Microwave Enhanced Freeze Drying Solid Waste (MEFDSW) processor was delivered to NASA-Ames Research Center by Umpqua Company having been funded through a Small Business Innovative Research Phase II program. The prototype hardware was tested for its performance characteristics and for its functionality with the primary focus being the removal of water from solid wastes. Water removal from wastes enables safe storage of wastes, prevents microbes from growing and propagating using the waste as a substrate and has potential for recovery and reuse of the water. Other objectives included measurements of the power usage and a preliminary estimate of the Equivalent System Mass (ESM) value. These values will be used for comparison with other candidate water removal technologies currently in development.

A microwave powered solid waste stabilization and water recovery prototype was delivered to Ames Research Center through an SBIR Phase II contract awarded to Umpqua Research Company. The system uses a container capable of holding 5.7 dm3 volume of waste. The microwave power can be varied to operate either at full power (130 W) or in a variable mode from 0% and 100%. Experiments were conducted with different types of wastes (wet cloth, simulated feces/diarrheal wastes, wet trash and brine) at different levels of moisture content and dried under varying microwave power supply. This paper presents the experimental data. The results provide valuable insight into the different operation modes under which the prototype can be used to recover water from the wastes in a space environment. Further investigations and testing of the prototype are recommended.

Water is of critical importance to space missions due to crew needs and the cost of supply. To control mission costs, it is essential to recycle water from all available wastes - both solids and liquids. Water recovery from liquid water wastes has already been accomplished on space missions. For instance, a Water Recycling System (WRS) is currently operational on the International Space Station (ISS). It recovers water from urine and humidity condensate and processes it to potable water specifications. However, there is more recoverable water in solid wastes such as uneaten food, wet trash, feces, paper and packaging material, and brine. Previous studies have established the feasibility of obtaining a considerable amount of water and oxygen from these wastes (Pisharody et al, 2002; Fisher et al, 2008; Wignarajah et al, 2008).

The On-line Project Information System (OPIS) is the Exploration Life Support (ELS) mechanism for task data sharing and annual reporting. Fiscal year 2008 (FY08) was the first year in which ELS Principal Investigators (PI's) were required to complete an OPIS annual report. The reporting process consists of downloading a template that is customized to the task deliverable type(s), completing the report, and uploading the document to OPIS for review and approval. In addition to providing a general status and overview of OPIS features, this paper describes the user critiques and resulting system modifications of the first year of OPIS reporting efforts. Specifically, this paper discusses process communication and logistics issues, user interface ambiguity, report completion challenges, and the resultant or pending system improvements designed to circumvent such issues for the fiscal year 2009 reporting effort.

To decrease consumable usage by current physico-chemical (P/C) air Trace Contaminant Control Systems (TCCS), there is an increased focus on developing regenerative TCCS technologies for long duration missions. This potentially includes reducing the need for disposable activated charcoal canisters (which pre-treat air prior to thermal catalytic treatment) as well as decreasing catalyst regeneration/replacement from eventual (and predictable) poisoning. Biofiltration is a low-energy, bio-regenerative air treatment technology capable of removing a variety of air contaminants and may substantially reduce loading to subsequent P/C TCCS components, thereby decreasing consumable usage. The design, operation and integration of biofilters are tightly coupled with waste stream characteristics. In particular, the inlet gas carbon to nitrogen ratio (C:N) will directly affect whether the system eventually becomes limited through nitrogen depletion or excess.

Advanced Life Support (ALS) systems designed for long-duration manned space missions, particularly permanent bases on the Moon or Mars, are likely to employ extensive use of regenerative closed loop systems, including the production of higher plants for food. Such systems will produce substantial amounts of inedible plant material in addition to other standard mission wastes. Composting is one of the several methods currently under investigation for waste processing and resource recovery in ALS systems. While composting is a robust microbiological process that can be utilized to treat a variety of organic materials under a wide range of environmental conditions, both feedstock preparation and process control require optimization. For instance, initial waste feedstock composition, carbon to nitrogen ratio (C:N), particle size, and moisture content are critical factors for ensuring optimal processing conditions and maximal rates of degradation.

BIO-Plex is a ground-based test bed currently under development by NASA for testing technologies and practices that may be utilized in future long-term life support missions. All aspects of such an Advanced Life Support (ALS) System must be considered to confidently construct a reliable system, which will not only allow the crew to survive in harsh environments, but allow the crew time to perform meaningful research. Effective handling of solid wastes is a critical aspect of the system, especially when recovery of resources contained in the waste is required. This is particularly important for ALS Systems configurations that include a Biomass Production Chamber. In these cases, significant amounts of inedible biomass waste may be produced, which can ultimately serve as a repository of necessary resources for sustaining life, notably carbon, water, and plant nutrients. Numerous biological and physicochemical solid waste processing options have been considered.

Composting is a biological solid waste treatment technology with potential use in the management of organic solid wastes generated within advanced life support (ALS) systems, such as planetary bases with extensive plant production. Composting can serve to decrease mass, volume and water content, as well as stabilize and sanitize waste materials. Composting may also serve as a pre-treatment system prior to aqueous extraction (for nutrient recovery) or incineration. Additionally, the compost produced may serve as a nutrient-rich plant growth substrate. Each of these treatment objectives exerts different compost quality requirements. It is necessary to accurately determine the processing time required for the specified treatment objectives prior to system design and analysis. For example, waste stabilization will require less processing time than production of composts suitable for plant growth.

Solid Waste Management (SWM) systems of current and previous space flight missions have employed relatively uncomplicated methods of waste collection, storage and return to Earth. NASA's long-term objectives, however, will likely include human-rated missions that are longer in both duration and distance, with little to no opportunity for re-supply. Such missions will likely exert increased demands upon all sub-systems, particularly the SWM system. In order to provide guidance to SWM Research and Technology Development (R&TD) efforts and overall system development, the establishment of appropriate SWM system requirements is necessary. Because future long duration missions are not yet fully defined, thorough mission-specific requirements have not yet been drafted.

Long duration missions pose substantial new challenges for solid waste management in Advanced Life Support (ALS) systems. These possibly include storing large volumes of waste material in a safe manner, rendering wastes stable or sterilized for extended periods of time, and/or processing wastes for recovery of vital resources. This is further complicated because future missions remain ill-defined with respect to waste stream quantity, composition and generation schedule. Without definitive knowledge of this information, development of mission requirements is hampered. Additionally, even if waste streams were well characterized, other operational and processing needs require clarification (e.g. resource recovery requirements and planetary protection constraints). Therefore, the development of solid waste management (SWM) subsystem requirements for long duration space missions is an inherently uncertain, complex and iterative process.

The On-line Project Information System (OPIS) is a LAMP-based (Linux, Apache, MySQL, PHP) system being developed at NASA Ames Research Center to improve Agency information transfer and data availability, largely for improvement of system analysis and engineering. The tool will enable users to investigate NASA technology development efforts, connect with experts, and access technology development data. OPIS is currently being developed for NASA's Exploration Life Support (ELS) Project. Within OPIS, NASA ELS Managers assign projects to Principal Investigators (PI), track responsible individuals and institutions, and designate reporting assignments. Each PI populates a “Project Page” with a project overview, team member information, files, citations, and images. PI's may also delegate on-line report viewing and editing privileges to specific team members. Users can browse or search for project and member information.

A workshop entitled the “Life Support & Habitation and Planetary Protection Workshop” was held in Houston, TX in April, 2005. The main objective of the workshop was to initiate communication, understanding, and a working relationship between the Life Support and Habitation1 (LSH) and Planetary Protection (PP) communities regarding the effect of the implementation of Mars human exploration PP policies on the Advanced Life Support2 (ALS), Advanced Extravehicular Activity (AEVA), and Advanced Environmental Monitoring and Control (AEMC) programs. This paper presents an overall summary of the workshop that includes workshop organization, objectives, starting assumptions, findings and recommendations. Specific result topics include the identification of knowledge and technology gaps, research and technology development (R&TD) needs, potential forward and back contaminants and pathways, mitigation alternatives, and PP requirements definition needs.

Newly outlined missions in the Vision for U.S. Space Exploration include extended human habitation on Mars. During these missions, large amounts of waste materials will be generated in solid, liquid and gaseous form. Returning these wastes to Earth will be extremely costly, and increase the opportunity for back contamination. Therefore, it is advantageous to investigate the potential for wastes to remain on Mars after mission completion. Untreated, these wastes are a reservoir of live/dead organisms and molecules considered “biomarkers” (i.e., indicators of life). If released to the planetary surface, these materials can potentially interfere with exobiology studies, disrupt any existent martian ecology and pose human safety concerns. Waste Management (WM) systems must therefore be specifically designed to control release of problematic materials both during the active phase of the mission, and for any specified post-mission duration.

The Advanced Life Support (ALS) Project has accelerated an effort to develop an On-line Project Information System (OPIS) for research and technology development (R&TD) data centralization and sharing. This paper presents the OPIS development strategy and status. OPIS is being built as an application framework consisting of an underlying Linux/Apache/MySQL/PHP (LAMP) stack and supporting class libraries, which provide database abstraction and automatic code generation. This approach simplifies the development and maintenance process. The approach also allows for quick adaptation to serve multiple Programs/Projects, although initial deployment is for an ALS module. Data will be located on a secure server at NASA Ames Research Center (ARC). Initial functionality of OPIS will involve a Web-based solicitation of project and technology data, directly from ALS Principal Investigators (PIs) through data collection forms.

An ongoing effort is underway at NASA Ames Research Center (ARC) to develop an On-line Project Information System (OPIS) for the Advanced Life Support (ALS) Program. The objective of this three-year project is to develop, test, revise and deploy OPIS to enhance the quality of decision-making metrics and attainment of Program goals through improved knowledge sharing. OPIS will centrally locate detailed project information solicited from investigators on an annual basis and make it readily accessible by the ALS Community via a Web-accessible interface. The data will be stored in an object-oriented relational database (created in MySQL®) located on a secure server at NASA ARC. OPIS will simultaneously serve several functions, including being an research and technology development (R&TD) status information hub that can potentially serve as the primary annual reporting mechanism for ALS-funded projects.

Accurate, flexible, and dynamic mathematical computer modeling tools are required for the development and parametric evaluation of the various possible Advanced Life Support Systems (ALSS) configurations. Such models are expected to take a top-level approach to maximize modularity, flexibility in development, and user/developer friendliness. Two approaches are taken for modeling the WPRR component of an ALSS: an object oriented approach coded in Java and a SIMULINK model. Each model exhibits distinct properties for the interchange of technologies, startup requirements, and hardware/software requirements, but are anticipated to provide successful ALSS models.

The growth of Swiss chard in compost, Mars regolith simulant, and mixtures thereof, was studied for application in Advanced Life Support (ALS) systems, particularly Mars/lunar based operations. The purpose was to begin characterizing a sustainable biomass production method based on compost derived from inedible biomass. Compost would serve both as a means of recycling plant nutrients while improving the physical qualities of regolith as a plant growth medium. An outpost’s cropping area could be expanded by blending a minimal amount of compost (scarce, initially imported resource) and a maximal amount of regolith (plentiful local resource), consistent with adequate crop yields. Swiss chard was selected for the study as it is an ALS crop candidate for which there are little data.