Contaminated Water Treatment

environment
Contaminated Water Treatment (TOP2-106)
A portable and low-cost method for recycling contaminated liquid
Overview
Scientists at NASA Ames have developed a method and system that offers a novel way of processing and recycling of liquids to remove contaminants. Space exploration requires a life-support system that sustains astronauts on journeys lasting from a few days to several weeks or longer. The life-support system must be designed to reduce the mass required to keep humans alive in space. Water accounts for about 80 percent of a humans daily mass intake. As a result, recycling water, including urine, offers a high return on investment for space exploration missions as well as increasing mission safety. It provides an emergency supply of drinking water, when other sources are exhausted or contaminated.

The Technology
This invention is a system and associated method that is a two step process. It provides a contaminant treatment pouch, referred to as a urine cell or contaminant cell that converts urine or another liquid containing contaminants into a fortified drink, engineered to meet human hydration, electrolyte and caloric requirements. It uses a variant of forward osmosis (FO) to draw water from a urine container into the concentrated fortified drink as part of a recycling stage. An activated carbon pretreatment removes most organic molecules. Salinity of the initial liquid mix (urine plus other) is synergistically used to enhance the precipitation of organic molecules so that activated carbon can remove most of the organics. A functional osmotic bag is then used to remove inorganic contaminants. If a contaminant is processed for which the saline content is different than optimal for precipitating organic molecules, the saline content of the liquid should be adjusted toward the optimal value for that contaminant.
The NASA developed technology could be used to produced recycled drinking water.
Benefits
  • Reduces the mass of potable water at launch
  • Renews/ recycles drinking water
  • Provides a temporary source of additional nutrients for use by a spacecraft occupant
  • Reduces the volume of biological waste stored aboard a spacecraft
  • Is biologically safe
  • Eliminates the need for urine dumping during space voyage
  • Is portable + low cost

Applications
  • Space missions
  • Army missions
  • Water source for developing world
  • Extreme environments like hiking/camping, yachting, and mountaineering
  • Antarctic exploration missions, etc.
Technology Details

environment
TOP2-106
ARC-15890-1
7,655,145
Progress in the Development of DirectOsmotic Concentration Wastewater Recovery Process for Advanced Life Support Systems, 2005, SAE Technical Paper 2005-01-3031, doi:10.4271/2005-01-3031.
Similar Results
Modular System for Waste Treatment, Water Recycling, and Resource Recovery
Because resupply of commodities for long duration space missions would be prohibitively expensive and could take an extensive length of time to reach habitats in orbit around or on other planetary bodies, it is critical that astronauts have the ability to recycle and reuse local waste streams to provide resources such as clean water, fuel, and nutrients for growing plants. Scientists at Kennedy Space Center and the University of South Florida have developed a technology that addresses this critical mission need. The modular system design incorporates all wastewater streams and some food waste including urine water, hygiene water, humidity condensate, Sabatier water, fecal waste, laundry water, and organic food waste. These sources are fed simultaneously into the system, and a function-driven, sequential purification process occurs. The primary processes include carbon conversion, phase separation (solid/liquid/gas), disinfection, nutrient/salts management, and salts balancing to generate a clean water stream. The heart of the closed-loop bio-regenerative system is an anaerobic membrane bioreactor (AnMBR), which takes raw wastewater streams and utilizes an anaerobic microbial consortium to carry out the breakdown of the organic matter. An ultrafiltration membrane captures and destroys pathogenic bacteria and viruses. The AnMBR system generates a clean water stream containing fertilizer constituents which can be used to cultivate either microalgae (for food, pharma/nutraceuticals, fuel or bioplastics) in photobioreactors or crops in hydroponic systems. The system also generates methane and hydrogen gas which can be used for fuel (or conversion to bioplastics), and CO2 which can be used to support plant growth.
Glass of purified water
Pre-Treatment Solution for Water Recovery
The pre-treatment solution increases the solubility of calcium in urine brines by reducing the concentration of sulfates. When the solution is properly dosed, it enables biological, physical, and chemical stabilization of flushed urine for storage and distillation up to a steady 87% water recovery, as realized aboard the U.S. segment of the ISS, without precipitation of minerals such as gypsum. Turning wastewater or seawater into potable water requires three important steps shared by the UPA and Water Recovery System (WRS) aboard the ISS: 1) pre-treatment, 2) distillation or membrane filtration, and 3) transport and storage of potable water and brine. Added during the first step, the pre-treatment solution improves the efficiency of the UPA by reducing the formation of solid precipitates caused by urinary calcium, sulfate ions, and sulfuric acid. This reduction in-turn creates less acidic brines which means more water can be recovered along with less surface scaling and clogging, further increasing recovery. As an added benefit, the solution contains a biocide that prevents the growth of bacteria and fungus, thereby increasing storage time of the treated urine. Although the pre-treatment solution was developed for the ISSs UPA , the technology can potentially be used on Earth to pretreat contaminated water from organic-laden, high-salinity wastewaters. Adding the solution is a simple process that can be scaled to fit demand. It has the potential to improve water recovery in many applications such as: desalination plants, brackish water treatment, mining water treatment, hydraulic fracturing operations, and more. The pre-treatment solution may also lend itself for use in the transport and storage of wastewater due to the solution's ability to prevent microbial growth.
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Air Revitalization for Vacuum Environments
The NASA life support system uses a regenerable vacuum swing adsorption process, known as Sorbent-Based Air Revitalization (SBAR), to separate water and carbon dioxide for disposal. The SBAR system is an adsorbent-based swing bed system that has been optimized to provide both humidity and carbon dioxide control for a spacecraft cabin atmosphere. The system comprises composite silica gel and zeolite-packed beds for adsorption and a bypass system for flow control. Under normal operating conditions, the disposal system would require a high-quality vacuum environment to operate. Improvements to the SBAR system include an enhanced inherent capacitance that extends the operation time within a non-vacuum environment for up to 4.5 hours. Flight time can be further expanded with multiple SBAR systems to allow for system regeneration. By scheduling periodic thermal regenerations&#151nominally during sleep periods&#151the SBAR technology may be suitable for missions of unlimited duration.
Wastewater Treatment and Remediation
NASA's system was developed for smaller-scale, space-based applications. However, the technology is scalable for larger industrial and municipal water treatment applications. Implementation of the Ammonia Recovery System could significantly reduce nitrogen content from water treatment processes, meaningfully improving the quality of water. This system offers a novel way to reduce nitrogen water pollutants, while allowing for the nitrogen to be collected and reused- reducing environmental and public health risks and providing an environmentally friendly fertilizer option. NASAs environmental solutions work to sustain life on earth through space based technology The adaptable nature of this system gives it potentially broad applications in a wide variety of industries; it is particularly ideal for on-site remediation of wastewater in places like condo complexes, hotels and water parks. Current methods of ammonia recovery could not meet NASAs mission requirements, so a new process was devised to optimize for high ammonia selectivity, simplicity, low volume , low power usage and zero contaminants in the effluent. To do this, NASA designed a novel regenerable struvite-formation system for the capture of ammonia. This system has three primary functions: 1) Removal of ammonia from wastewater using a media that is highly selective for ammonia 2) Capture of the ammonia for later use (e.g., as a fertilizer) 3) Regeneration of the capture media for reuse in the system
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Habitat Water Wall for Water, Solids, and Atmosphere Recycle and Reuse
This approach allows water recycling, air treatment, thermal control, and solids residuals treatment and recycle to be removed from the usable habitat volume and placed in the walls of a radiation-shielding water wall. It also provides a mechanism to recover and reuse water treatment (solids) residuals to strengthen the habitat shell. Water-wall treatment elements are a much-enlarged version of the commercially available X-Pack hydration bag. Some water bags have pervaporation membranes facing inward that provide the capability to remove H0, C0, and trace organics from the atmosphere. Ideally the water wall is composed of a series of membrane bags packed as dry elements integrated into an inflatable habitat structure wall. After launch and deployment, it is filled with water and maintained as both a freshwater supply and radiation shield. As the initial water supply is consumed, the depleted treatment bags are filled with waste water and take on a dual role of active forward osmosis (FO) water treatment and water-wall radiation shielding.
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