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Gregory S Pace

Publications and source records attributed to Gregory S Pace.

The Trash Compaction Processing Systems (TCPS) Ground Unit Control Sample Testing

The Trash Compaction Processing System (TCPS) is being developed by NASA and Sierra Space to process crew trash for long-duration missions. The system compacts and thermally processes mixed spacecraft waste to reduce volume and stabilize the material while managing gas and liquid effluents. A Ground Unit (GU) located at Sierra Space in Madison, Wisconsin was used to run a series of tests using standardized control samples representing different trash conditions, including nominal, high liquid, high cloth, benign, and foam. Gas grab samples were collected during processing and analyzed to identify the compounds present in the effluent stream and compare the concentrations to the NASA spacecraft maximum allowable concentrations (SMACs). Additional testing included odor testing at White Sands Test Facility, aerosol measurements, microbiology, and tile characterization. Overall, the compounds detected in the gas samples were well below the SMAC limits for all trash models tested. The results from this testing are being used to help guide the verification approach and test planning for the TCPS Flight Unit that is planned for on-orbit testing on the International Space Station.

Control Samples↗

Development of an Adsorption System for the Trash Compaction Processing System designed for operation in the International Space Station Express Rack

A water recovery system that utilizes adsorption to work with the Trash Compaction Processing System, formerly known as the Heat Melt Compactor, is being designed at NASA Ames Research Center as an option to current state of the art micro-gravity water management systems and contaminant control systems used in space. The adsorption system will be used in conjunction with the International Space Station Vacuum Exhaust system to avoid both the complexities of gas liquid phase separation in micro-gravity and venting of Trash Compaction Processing System effluents to the spacecraft cabin. The adsorption system will allow the water and gaseous effluents generated during the Trash Compaction System operation to be removed in a matter that meets the Vacuum Exhaust System venting rate requirements. The Trash Compaction Processing System is planned to fly as a Technology Demonstration on the International Space Station in the space station EXPRESS Rack facility. This paper describes the trade space that the adsorption system must operate in using the EXPRESS Rack facilities resources including the use of the Space Station Vacuum Exhaust System. Also described in this paper are design solutions to allow the adsorption system to function within the Express Rack and Vacuum Exhaust System Parameters.

Heat Melt Compactor↗

Gas Effluent Analysis of the Heat Melt Compactor

The Heat Melt Compactor (HMC) reduces volume, heat sterilizes, stabilizes, and manages gas and water effluent of the International Space Station (ISS) trash. Processing the trash at high temperatures produces volatile gas compounds that need to be treated before venting to cabin and/or the Vacuum Exhaust System (VES) in the ISS. The release of gases may not meet the Spacecraft Maximum Allowable Concentrations (SMAC) requirement, if vented directly into cabin, and/or gases are incompatible for venting to the VES. In order to assess the HMC gas release and venting parameters, effluent gas analysis is conducted to determine contaminant load. This paper will analyze different collection and analytical methods of the effluent gas, and report corresponding data, such that these results can be used for process design and effluent management.

Heat Melt Compactor↗

Reduction of Equivalent System Mass of a Trash Compaction Processing System with an Emphasis on Improved Thermal Efficiency

A device known as the Trash Compaction Processing System or TCPS has been under development at NASA as part of the Advanced Life Support and Logistics Reduction Program Waste Management element. The TCPS processes trash that includes a variety of components such as plastic pouches that contain wet food and drinks, used cloth towels and t-shirts, adhesive tapes, deodorant, and many other items. The TCPS uses heat and pressure to compact the waste composite into a sturdy and well-defined shape designed to fit in a storage area on a spacecraft. The TCPS removes water from the trash and renders it safe against microbial activity. The focus of this paper is on methods for reducing the Equivalent System Mass of a TCPS with an emphasis on increasing the thermal efficiency of the system.

Trash Compaction Processing System↗

Source Contaminant Control System Design, Operation, and Testing for the Trash Compaction and Processing System

The Trash Compaction and Processing System (TCPS) aims to reduce volume, biologically safen, physically stabilize, manage effluents, and recover resources from astronaut trash in the International Space Station (ISS). This process involves heating the trash to high temperatures, which in turn releases gaseous contaminants. Effluent management scenarios involve releasing these gases back to the ISS cabin after processing and/or directly venting these gases out to space via the Vacuum Exhaust System (VES). Concerns for recovering the gases back to cabin are crew health, safety, and spacecraft environmental impact. The Heat Melt Compactor (HMC) at NASA Ames Research Center (ARC) serves as a test system that supports TCPS development by conducting risk reduction activities associated with an ISS flight demonstration. Previous gas effluent studies were conducted on the HMC. The results consisted of contaminants from the trash exhaust to exceed Spacecraft Maximum Allowable Concentrations (SMAC), which are selected airborne contaminants that can elicit toxicity symptoms to crewmembers via exposure. The Source Contaminant Control System (SCCS) aims to reduce that risk by converting the contaminants into carbon dioxide (CO2) and water (H2O) vapor. The SCCS is composed of a carbon adsorbent bed, to avoid catalyst poisoning, and a catalytic oxidizer (CatOx), which promotes oxidation of the contaminants to CO2and H2O. In turn, the gases coming out of the SCCS should be compatible to the ISS cabin and systems such as the Trace Contaminant Control System (TCCS). Preparation for SCCS testing alongside the HMC Gen 3 are currently underway at ARC. The main objectives are to evaluate CatOx efficiency by CO2conversion and characterize effectiveness of removal by comparing contaminant results before and after CatOx. This paper will report on the SCCS design, operation, and testing with results.

TCPS↗

Waste Container Filtration To Minimize Microbial Escape During Long-Term Storage On Mars

In the search for life on Mars, keeping its surface pristine and free of microbes due to human presence is of utmost importance. Astronauts will use emptied logistics containers during their Martian stay to store waste. These containers will be left on the planet’s surface and are a potential source of microbial contamination. It is desired for these containers to be free from leaks for a minimum of 50 years. If leaks do occur a likely location will be at the port. At this location the mating surfaces will be sealed using a flexible gasket material like a thin metal or a polymer. Eventually these seals will fail. To mitigate these effects, a particulate filter can be employed to equilibrate the pressure between the Martin environment and inside the container. To meet planetary protection requirements, the filter can only allow particulates smaller than 0.2 um diameter to pass. This paper discusses why a particulate filter may be needed and how such a filter would be tested to survive and operate in the harsh Martian environment.

Planetary Protection Waste Containment↗

The Trash Compaction Processing System (TCPS) Technology Demonstration and Risk Reduction Updates FY23-FY24

The Next STEP Phase BTrash Compaction Processing System (TCPS) is being developed for a technology demonstration on the International Space Station(ISS) to process common spacecraft consumables trash such as food packaging and clothing to reduce trash storage volume, recover water, safen(e.g. reduce biological activity), and shape the trash for storage, jettison, reuse (e.g.,radiation shielding) and/or recycling. Sierra Space is developing the flight demonstration hardware and National Aeronautics and Space Administration(NASA) continues to conduct risk reduction activities to exploreoperational scenarios, setting the stage for successful on-orbit tests. After the flight demonstration on ISS, the TCPS becomes available to be infused into NASA short-and long-term missions.This paper will discuss the rationale for the updated requirement definitions outlined in the 2023 International Conference on Environmental System TCPS paper and the ongoing risk reduction activities. In addition, drawing from lessons learned in the development of the TCPS, a discussion of other compression technologies will be introduced for various mission types.

Trash Compaction Processing System↗

Reduction of the Equivalent System Mass of a Trash Compaction Processing System Designed for Human Spaceflight Waste Management by Improving its Thermal Efficiency

A spacecraft life support system has been under development at NASA called the Trash Compaction Processing System that manages trash generated on human spaceflight missions. The trash composite typically includes components such as plastic pouches that contain wet food and drinks, used cotton clothing such as underwear and T-shirts, exercise clothing, used washcloths, expended deodorant containers, adhesive tapes, plastic bubble wrap, and other sundry items. The system uses compaction in combination with heat to turn the waste composite into a sturdy and well-defined shape, typically called a tile, which maintains structural integrity and makes the most efficient use of storage space. In addition to reducing the volume of the trash, the Trash Compaction Processing System removes water from the trash. The heating and removal of water from the trash renders it safe against microbial activity. This paper primarily focuses on work aimed at reducing the Equivalent System Mass of a Trash Compaction Processing System via a focus on improving the system’s thermal efficiency.

TCPS↗

The Trash Compaction Processing System (TCPS) Technology Demonstrations and Risk Reduction Activities 2023-2024

The Trash Compactor Processing System (TCPS) employs heat and pressure to safely compress spacecraft trash. The Next STEP Phase B Appendix 2 contract was awarded to Sierra Space for the development of ground and flight demonstration hardware, slated for testing on the International Space Station in 2026. Meanwhile, Ames Research Center is actively engaged in risk reduction activities related to in-house hardware, fine-tuning science objectives and test procedures.This paper will discuss the updated TCPS requirements and present the results of the risk reduction activities, which include moisture analysis, component offgas, and aerosol analysis.

Justine Tra-my Richardson↗

Updated Analysis of the Source Contaminant Control System (SCCS) for the Trash Compaction and Processing System (TCPS)

The Trash Compaction and Processing System (TCPS) aims to reduce volume, biologically safen, physically stabilize, manage effluents, and recover resources from astronaut trash in the International Space Station (ISS). This process involves heating the trash to high temperatures, which in turn releases gaseous contaminants. A Source Contaminant Control System (SCCS) is planned to be implemented within the TCPS to convert these contaminants into carbon dioxide (CO 2 ) and water (H 2 O) vapor. The SCCS is composed of a carbon adsorbent bed, to avoid catalyst poisoning, and a catalytic oxidizer (CatOx), which promotes oxidation of the contaminants to CO 2 and H 2 O. In turn, the gases coming out of the SCCS should be compatible to the ISS cabin and systems such as the Trace Contaminant Control System (TCCS). This paper will individually evaluate the carbon bed and CatOx to understand what components the carbon bed removes and what contaminants are converted in the CatOx. Overall, this is an updated analysis of the SCCS design, operation, testing with results, and lessons learned.

Janine Criselda Young↗

Water Collection, Recovery, and Bag Containment Analysis of Trash Models of the Trash Compaction and Processing System (TCPS)

The Trash Compaction and Processing System (TCPS) aims to reduce volume, biologically safen, physically stabilize, manage effluents, and recover resources from astronaut trash in the International Space Station (ISS). The Heat Melt Compactor (HMC) at NASA Ames Research Center (ARC) serves as a test system that supports TCPS development by conducting risk reduction activities associated with an ISS flight demonstration. One of the resources desired to be recovered is water from the trash. The HMC Gen 3 has undergone several tests of different trash models and cases in which a containment bag is used or not. This paper will analyze the water collected and recovered from these tests and analyze the effect of specific trash containment bags.

Janine Criselda Young↗

Zotek® F30 Foam Processing in the Trash Compaction and Processing System (TCPS)

The Trash Compaction and Processing System (TCPS) aims to reduce volume, biologically safen, physically stabilize, manage effluents, and recover resources from astronaut trash in the International Space Station (ISS). The Heat Melt Compactor (HMC) at NASA Ames Research Center (ARC) serves as a test system that supports TCPS development by conducting risk reduction activities associated with an ISS flight demonstration. One of the risk reduction activities is to test processing for other types of trash models. A foam model was added to reduce the volume of foam that takes up space in the ISS. This paper will discuss Zotek® F30 foam processing in the HMC unit and testing verification in correlation to defined TCPS requirements.

Janine Criselda Young↗

Zotek® F30 Foam Processing in the Trash Compaction and Processing System

The Trash Compaction and Processing System (TCPS) aims to reduce volume, biologically safen, physically stabilize, manage effluents, and recover resources from astronaut trash in the International Space Station (ISS). The Heat Melt Compactor (HMC) at NASA Ames Research Center (ARC) serves as a test system that supports TCPS development by conducting risk reduction activities associated with an ISS flight demonstration. One of the risk reduction activities is to test processing for other types of trash models. A foam model was added to reduce the volume of foam that takes up space in the ISS. This paper will discuss Zotek® F30 foam processing in the HMC unit and testing verification in correlation to defined TCPS requirements.

Janine Young↗

Reduction of Equivalent System Mass of a Trash Compaction Processing System with an Emphasis on Improved Thermal Efficiency

A spacecraft life support system has been under development at NASA called the Trash Compaction Processing System that manages trash generated on human spaceflight missions. The trash composite typically includes components such as plastic pouches that contain wet food and drinks, used cotton clothing such as underwear and T-shirts, exercise clothing, used washcloths, expended deodorant containers, adhesive tapes, plastic bubble wrap, and other sundry items. The system uses compaction in combination with heat to turn the waste composite into a sturdy and well-defined shape, typically called a tile, which maintains structural integrity and makes the most efficient use of storage space. In addition to reducing the volume of the trash, the Trash Compaction Processing System removes water from the trash. The heating and removal of water from the trash renders it safe against microbial activity. This paper primarily focuses on work aimed at reducing the Equivalent System Mass of a Trash Compaction Processing System via a focus on improving the system’s thermal efficiency.

Trash Compaction Processor↗

The Trash Compaction Processing System (TCPS) Technology Demonstration and Risk Reduction Updates FY23-FY24 Presentation

The Next STEP Phase BTrash Compaction Processing System (TCPS) is being developed for a technology demonstration on the International Space Station(ISS) to process common spacecraft consumables trash such as food packaging and clothing to reduce trash storage volume, recover water, safen(e.g. reduce biological activity), and shape the trash for storage, jettison, reuse (e.g.,radiation shielding) and/or recycling. Sierra Space is developing the flight demonstration hardware and National Aeronautics and Space Administration(NASA) continues to conduct risk reduction activities to exploreoperational scenarios, setting the stage for successful on-orbit tests. After the flight demonstration on ISS, the TCPS becomes available to be infused into NASA short-and long-term missions.This paper will discuss the rationale for the updated requirement definitions outlined in the 2023 International Conference on Environmental System TCPS paper and the ongoing risk reduction activities. In addition, drawing from lessons learned in the development of the TCPS, a discussion of other compression technologies will be introduced for various mission types.

Trash Compaction Processing System↗

Development of a Mechanical Trash Compactor (Mpactor) for Exploration Missions

NASA is developing a mechanical trash compactor (Mpactor), a pneumatically driven trash compaction system, for human space exploration missions to manage trash items such as food packaging, sanitary wipes, clothing, tape, and other types of waste. The compaction system that is under development does not involve heating, water removal, or water recovery which eliminates the need for complex ancillary hardware required to manage gaseous effluents, as well as condense the water vapor. A system called the Crew Exploration Vehicle (CEV) Compactor, intended for use in the micro-gravity environment, was developed at NASA Ames Research Center for the Constellation Program 2007. This CEV Compactor is being further developed and renamed the Mpactor (short for mechanical trash compactor). The Mpactor is being used to gather engineering data that will allow engineers and planners to scale a future design for different mission scenarios and to evaluate different bag materials and designs that help retain compaction.

transit vehicle↗

Characterization of the Mechanical Trash Compactor Bag Removal Force

Managing trash accumulation is a critical challenge in human space explorations since the trash volume and mass can significantly influence launch cost and operational efficiency. This study aids the development of a Mechanical Trash Compactor (Mpactor) by testing the removal force required to remove a “trash bag” from the Mpactor. To do this, a Pneumatic Pressure Mandrel System was designed to simulate the normal force trash would exerts on the trash bag and subsequently the sidewalls of the Mpactor. For various levels of sidewall normal force, the removal force required to remove the simulated trash bag from the Mpactor compaction chamber was measured. This testing is used to identify optimal bag materials. Additionally, testing was done on both the native stainless steel walls of the compaction chamber as well as the walls after being Teflon lined. Split-plot ANOVA, simple main effects analysis, Holm’s post hoc comparisons for interaction, and sensitivity analyses were conducted to assess the influence of trash bag and sidewall materials on the required removal force. It was found that Teflon reduced the force required to remove the trash bag as well as reduced material-dependent variation in removal force. Testing showed that Teflon reduced the required removal force with a Polyvinylidene Fluoride , an unidentified Ethylene acrylate - Low Density Polyethylene copolymer, and a Polyvinyl Chloride all requiring significantly less removal force than the other materials tested.

pressure mandrel↗