Browse Topic: Water pollution

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Pre-Treatment Solution for Water RecoveryTBMG-3959508/01/2021
The Pre-Treatment Solution for Water Recovery was developed by NASA Johnson to increase the amount of potable water recovered from the International Space Station’s urine processor assembly system. Turning wastewater, urine, or seawater into potable water requires three important steps: 1) pre-treatment, 2) distillation or membrane filtration, and 3) transport and storage of potable water and brine. This solution is added during the first step, consequently improving the next steps in the process primarily by reducing the formation of solid precipitates.
Wireless Aquatic Robot Cleans WaterTBMG-3738908/01/2020
Researchers have developed a tiny plastic robot, made of responsive polymers, that moves under the influence of light and magnetism. In the future, this wireless aquatic polyp should be able to attract and capture contaminant particles from the surrounding liquid or pick up and transport cells for analysis in diagnostic devices.
Bacteria-Based Hydrogel Beads Clean Up Contaminated GroundwaterTBMG-3745108/01/2020
Hydrogel beads with the consistency of gummy candy are made with an ingredient used in processed foods to clean up groundwater contaminated with dangerous and widely used volatile organic compounds (VOCs). Among the contaminants addressed by the method are 1,1,1-trichloroethane, cis-1,2-dichloroethene, and 1,4-dioxane — degreasers commonly used by industry and the military. The chemicals can infiltrate groundwater through leaky underground storage tanks or runoff, or by simply being dumped on the ground.
Use of Mass-Flux Measurement and Vapor-Phase Tomography to Quantify Vadose-Zone Source Strength and Distribution20AERP08_1008/01/2020
Use of advanced technologies could improve evaluation of vadose zone source impacts on groundwater and vapor intrusion, leading to improved remediation decisions. Environmental Security Technology Certification Program, Alexandria, Virginia The goal of this project was to demonstrate that the multistage vapor-phase contaminant mass discharge (MS-CMD) test and vapor-phase tomography (VPT) can effectively characterize persistent volatile organic compound (VOC) sources in the vadose zone and measure their associated mass discharge. It is anticipated that these technologies will improve evaluation of vadose zone source impacts on groundwater and vapor intrusion. The U.S. Department of Defense (DoD) has focused significant effort on characterizing and treating chlorinated solvent sources in groundwater. There are two primary concerns associated with sites that contain vadose zone volatile organic compound (VOC) sources. First, discharge of contaminant vapor from the vadose zone source may
Smart Sponge for Environmental RemediationTBMG-3744108/01/2020
Oil spill cleanup is an expensive and complicated process that often harms marine life and further damages the environment. Currently used solutions include burning the oil, using chemical dispersants to breakdown oil into very small droplets, skimming oil floating on top of water, and/or absorbing it with expensive, unrecyclable sorbents. Burning increases carbon emissions and dispersants are harmful for marine wildlife. Skimmers don’t work in rough waters or with thin layers of oil. Sorbents are not only expensive but generate a huge amount of physical waste.
Portable Tool Analyzes Microbes in the EnvironmentTBMG-3745508/01/2020
Researchers have developed a device that swiftly analyzes microbes in oceans and other aquatic environments, revealing the health of these organisms — too tiny to be seen by the naked eye —and their response to threats to their ecosystems. The portable device could be used to assess microbes, screen for antibiotic-resistant bacteria, and analyze algae that live in coral reefs.
Use of Mass-Flux Measurement and Vapor-Phase Tomography to Quantify Vadose-Zone Source Strength and DistributionTBMG-3737408/01/2020
The goal of this project was to demonstrate that the multistage vapor-phase contaminant mass discharge (MS-CMD) test and vapor-phase tomography (VPT) can effectively characterize persistent volatile organic compound (VOC) sources in the vadose zone and measure their associated mass discharge. It is anticipated that these technologies will improve evaluation of vadose zone source impacts on groundwater and vapor intrusion.
Process Turns Sand and Plant Materials into a Water Filtration ToolTBMG-3581901/01/2020
According to the United Nations, 2.1 billion people lack access to safely managed drinking water services and the majority live in developing nations. A process was developed that uses sand and plant materials readily available in many developing nations to create a cheap and effective water filtration medium called “f-sand.” F-sand uses proteins from the Moringa oleifera plant, a tree native to India that grows well in tropical and subtropical climates. The tree is cultivated for food and natural oils, and the seeds are already used for a type of rudimentary water purification; however, this traditional means of purification leaves behind high amounts of dissolved organic carbon (DOC) from the seeds, allowing bacteria to regrow after just 24 hours. This leaves only a short window in which the water is drinkable.
Smartphone Test Spots Poisoned Water RiskTBMG-3473107/01/2019
Researchers have developed a biosensor that attaches to a smartphone and uses bacteria to detect unsafe arsenic levels. The device generates easy-to-interpret patterns similar to volume-bars that display the level of contamination.
Researchers Create Smartphone System to Test for Lead in WaterTBMG-3442105/01/2019
Researchers at the University of Houston have created an inexpensive system that can detect lead in tap water at levels commonly accepted as dangerous, using a lens made with an inkjet printer and a smartphone.
5 Ws of the Lead-Detection Smartphone SystemTBMG-3358601/01/2019
Individuals needing or wanting to examine lead content in their drinking water on-demand and in virtually any environmental setting.
Paper-Based Electrochemical Test Strip Detects Harmful BacteriaTBMG-2721807/01/2017
Borrowing concepts from medical diagnostic devices, researchers have created a simple, inexpensive set of handheld tests that can detect the presence of many water- or food-borne pathogens. If applied in the field, such tests could greatly reduce the number of expensive follow-up tests needed to keep the food supply safe from fecal contamination.
Filtering Molecules with Nanotube TechnologyTBMG-2636002/01/2017
Innovators at NASA's Johnson Space Center have developed a filtration device to eliminate contaminants from water supplies. Originally developed to purify waste-water for reuse aboard the International Space Station, the innovation is applicable to numerous situations on Earth where there is a need to collect potable, medical-grade water from a contaminated water supply. The unique aspect of the technology is its use of acoustics, rather than pressure, to drive water through small-diameter carbon nanotubes. The invention requires less power than conventional filtration systems, and is well-suited to a variety of water processing needs.
Vibration Reduction of Single Cylinder Diesel Engine used for Agricultural Water Pumping2015-01-229106/15/2015
There are many environmental issues in India. Air pollution, water pollution, garbage, vibration, noise pollution and pollution of the natural environment are all challenges for India. India has a long way to go to reach environmental quality similar to those enjoyed in developed economies. Pollution remains a major challenge and opportunity for India. The review of trends in farm practices and machinery development suggests that vibration & noise problems are still prevalent in agricultural situations, even though there has been a steady increase in the availability of materials and equipment for vibration & noise control over recent years. Diesel engine is the main source of power for agricultural equipments, such as water pump set, compressor, electric generator and tractor. Even it is one of the sources of vibration & noise in agricultural field. There is reluctance of the agricultural sector to use of vibration & noise control methods. It is difficult to estimate the number of
Jadhav, Pandurang Maruti, Dunung, Sandesh A, Nitnaware, Pravin T
Microwave-Steam Based Road Deicing Vehicle Focused on Thin Ice Layers2015-01-050204/14/2015
For the thin ice on the road in winter, the traditional road deicing vehicle relies on mechanical and chemical methods for melting ice, which is inclined to damage the pavement and has insidious influence on environment. The thermal deicing vehicle has been adopted in recent years. Although the deicing method is available, the deicing efficiency is unacceptable while the energy consumption is huge. The study adopts the new idea of “bottom-to-top” for melting the intersection area between the road surface and the bottom ice layer by the microwave heating firstly and then cleaning them out using high pres. vapor cutting so as to save the cost of energy and enhance the traffic safety. First of all, the mathematical model of the melting process of the intersection of the pavement and the ice layer was established according to the microwave heating characteristics. Then the mechanism about the compatibility between the steam temperature, saturation and the upper surface of the ice was
Xu, Zhicheng, Tan, Gangfeng, Sun, Xingzhi, Ge, Yongqiang, Hua, Min, Xu, Haobo
Study of Singlemode Expanded-Beam Terminus for Enhanced Optical Performance2014-01-212909/16/2014
Fiber optic physical contact connection technology has been used with multimode fiber in civilian aircraft for over 30 years with very good proven reliable performance. The extensive use of singlemode fiber (SMF) in FTTx Telecom market rollouts speeds up the development of passive optical components which significantly decreases the cost, expands capability and increases the reliability level of singlemode components. SMF transmission seems mandatory for future applications even in mil-aero and other harsh environment applications due to increased data rate requirements and new sensors applications. In harsh environment applications, is it realistic to use SMF with cores that are 30 times smaller in area compared to multimode fiber (MMF) when highly exposed to contamination? The present paper presents a technology of beam expansion interconnection that mixes a physical contact (PC) with an expanded optical surface. The optical connector brings together benefits of both technologies
Metzger, Vincent, Parker, Douglas, Philippe, Alain, Claudot, Sebastien
The Development of Novel Fuel Dehydrating Icing Inhibitors2013-01-216909/17/2013
Dissolved water is a normal component of jet fuel which is vapourised during combustion; however, free water is a contaminant that can starve engines, freeze to form ice crystals capable of blocking fuel feeds, support microbial growth, and contribute towards corrosion. Jet fuel may be protected from the potentially hazardous effects of free-water using biocides and icing/corrosion inhibitors. This investigation seeks to identify novel chemical approaches to the dual management of both water contamination and ice formation in jet fuel. The strategy of using organic molecules as dehydrating agents remains a relatively neglected approach perhaps because of the complexity of the physical organic chemistry involved in developing and refining these systems. However, organic molecules with well characterised dehydrating properties - such as ortho esters, acetals, hemiacetals, ketals, and hemiketals - present themselves as an excellent starting-point for the development and optimisation of
Repetto, Sonia L., Costello, James F., De Lacy Costello, Benjamin, Ratcliffe, Norman M., Lam, Joseph K.-W.
Sheet Membrane Spacesuit Water Membrane EvaporatorTBMG-1549701/01/2013
A document describes a sheet membrane spacesuit water membrane evaporator (SWME), which allows for the use of one common water tank that can supply cooling water to the astronaut and to the evaporator. Test data showed that heat rejection performance dropped only 6 percent after being subjected to highly contaminated water. It also exhibited robustness with respect to freezing and Martian atmospheric simulation testing. Water was allowed to freeze in the water channels during testing that simulated a water loop failure and vapor backpressure valve failure. Upon closing the backpressure valve and energizing the pump, the ice eventually thawed and water began to flow with no apparent damage to the sheet membrane.
Mathematical Model of Water Contamination in Aircraft Fuel Tanks2011-01-254010/18/2011
Water is a contaminant that can lead to fuel system icing, microbial contamination, corrosion and fuel quantity gauging problems and therefore an efficient water management system is required in order to maximise the performance of an aircraft's fuel system. This paper describes a time-transient aircraft fuel tank model with water contamination, due to the principal mechanisms of dissolution, suspension, condensation and transportation. The tank model presented is a component of the NEPTUNE fuel system model which was developed for Airbus using the A380 as an example aircraft. A description of the physics of water contaminated fuel is given and of how this has been incorporated into a mathematical model of an aircraft fuel tank. A modular approach is demonstrated which enables interconnecting fuel tanks to be configured in larger systems in a flexible and easily understood manner.
Tomlinson, Stephen, Barker, Matt, Venn, Darran, Hickson, Luke, Lam, Joseph Kah-Wah
Effect of Contamination on Acoustic Performance of Microperforated Panels2011-01-162705/17/2011
Microperforated panel (MPP) absorbers are rugged, non-combustible, and do not deteriorate over time. That being the case, they are especially suitable for long term use in harsh environments. However, the acoustic performance is modified when contaminated by dust, dirt, or fluids (i.e. oil, water). This paper examines that effect experimentally and correlates the absorption performance with Maa's theory for micro-perforated panels. Transfer impedance and absorption coefficient are measured for different levels of aluminum oxide and carbon dust accumulation. The amount of dust contamination is quantified by measuring the luminance difference between clean and dirty panels with a light meter. The porosity and hole diameter in Maa's equation are modified to account for dust obstruction. The effect of coating the MPP with oil, water, and other appropriate viscous fluids was also measured. This effect was simulated by modifying the viscous factor in Maa's equation.
Liu, J., Herrin, D. W.
NASA Water Purification Improves Dental CareTBMG-931803/01/2011
Going to the dentist is always a less-than-welcome experience. However, a water purification technology developed for NASA could lead to a more satisfying end result and cleaner teeth.
Enhancing the Removal of Chlorocarbons From GroundwaterTBMG-TB-00742402/11/2010
Sonication apparently removes corrosion products that inhibit dechlorination. Experiments have shown that ultrasound could be an effective means of enhancing the removal of chlorinated hydrocarbon contaminants from groundwater by the zero-valent-metal treatment process. This process, which has been a subject of research in recent years, is attractive because it does not involve above-ground treatment or the use of pumps, and because the materials needed to effect treatment are safe and relatively inexpensive.
Hybrid Regenerative Water-Recycling SystemTBMG-TB-00709301/25/2010
A wastewater-recycling system contains biological and physicochemical water-treatment units. The system is suitable for use in environments in which clean water supplies are limited. Waste streams containing urine and washwater are purified into potable water with a recovery rate of 99 percent. The system includes a two-stage trickling-filter bioreactor, a reverse-osmosis unit, and a photocatalytic post-treatment subsystem. The first stage of the bioreactor reduces the concentrations of organic (carbon-based) compounds, while the second stage removes nitrogen compounds. The effluent from the reactor is sent to the reverse-osmosis unit, which passes 85 percent of the water and diverts the other 15 percent into a concentrated brine. Water is recovered from the brine by evaporation. Finally, the water is treated by ultraviolet light and titanium oxide for disinfection and for oxidation of any organic residue. The system can treat small amounts of very concentrated wastewater, without use
In-Line Filtration Improves Hygiene and Reduces ExpenseTBMG-651011/01/2009
Water is highly prized in the unforgiving realm of space travel and habitation. Ample water reserves for drinking, food preparation, and bathing would take up an inordinate amount of storage space and infrastructure, which is always at a premium on a vessel or station. Water rationing and recycling are thus an essential part of daily life and operations on the space shuttles and International Space Station (ISS). The Environmental Control and Life Support System (ECLSS), under continuing development at Marshall Space Flight Center in Alabama, helps astronauts use and reuse their supplies of water.
Filtering Water by Use of Ultrasonically Vibrated NanotubesTBMG-560909/01/2009
Devices that could be characterized as acoustically driven molecular sieves have been proposed for filtering water to remove all biological contaminants and all molecules larger than water molecules. Originally intended for purifying wastewater for reuse aboard spacecraft, these devices could also be attractive for use on Earth in numerous settings in which there are requirements to obtain potable, medical-grade, or otherwise pure water from contaminated water supplies. These devices could also serve as efficient means of removing some or all water from chemical products — for example, they might be useful as adjuncts or substitutes for stills in the removal of water from alcohols and alcoholic beverages. These devices may be constructed using various materials, such as ceramics, metallics, or polymers, depending on end-use requirements.
Ersatz Formulas for Lunar Outpost Wastewater and Brine2009-01-240207/12/2009
Early development of wastewater and brine processing equipment must rely upon ersatz formulations because authentic urine and hygiene water are variable in composition, difficult to acquire in quantity, and have limited storage life. Previous wastewater ersatz formulations (e.g. Verostko et al, 2004) were designed for chemical fidelity, to match the elemental ratios and VOC profile of defined blends of wastewater components. This paper presents an alternative spreadsheet approach to brine and wastewater ersatz formulation by combining “building block” recipes in user-selected ratios and accounting for compositional shifts upon evaporation.
Hunter, Jean B., Arquiza, JMR Apollo, Sahbaz, Jasmin
Benchtop Antigen Detection Technique Using Nanofiltration and Fluorescent DyesTBMG-523205/01/2009
The designed benchtop technique is primed to detect bacteria and viruses from antigenic surface marker proteins in solutions, initially water. This inclusive bio-immunoassay uniquely combines nanofiltration and near infrared (NIR) dyes conjugated to antibodies to isolate and distinguish microbial antigens, using laser excitation and spectrometric analysis. The project goals include detecting microorganisms aboard the International Space Station, space shuttle, Crew Exploration Vehicle (CEV), and human habitats on future Moon and Mars missions, ensuring astronaut safety. The technique is intended to improve and advance water contamination testing both commercially and environmentally as well. Lastly, this streamlined technique poses to greatly simplify and expedite testing of pathogens in complex matrices, such as blood, in hospital and laboratory clinics.
International Space Station USOS Potable Development Water Dispenser2008-01-201006/29/2008
The International Space Station (ISS) Russian Segment currently provides potable water dispensing capability for crewmember food and beverage rehydration. All ISS crewmembers rehydrate Russian and U.S. style food packages from this location. A new United States On-orbit Segment (USOS) Potable Water Dispenser (PWD) is under development. This unit will provide additional potable water dispensing capability to support an on-orbit crew of six. The PWD is designed to provide incremental quantities of hot and ambient temperature potable water to U.S. style food packages. It will receive iodinated water from the Fuel Cell Water Bus in the U.S. Laboratory element. The unit will provide potable-quality water, including active removal of biocidal iodine prior to dispensing. A heater assembly contained within the unit will be able to supply up to 2.0 liters of hot water (65 to 93°C) every thirty minutes. This quantity will allow three to four crewmembers to rehydrate their food and beverages from
Shaw, Laura A., Barreda, Jose L.
Two Devices for Removing Sludge From Bioreactor WastewaterTBMG-242711/01/2007
Two devices — a magnetic separator and a special filter denoted a self-regenerating separator (SRS) — have been developed for separating sludge from the stream of wastewater from a bioreactor. These devices were originally intended for use in microgravity, but have also been demonstrated to function in normal Earth gravity.
Two Devices for Removing Sludge From Bioreactor WastewaterTBMG-TB-00242711/01/2007
These devices can operate continuously and are self-cleaning. Two devices — a magnetic separator and a special filter denoted a self-regenerating separator (SRS) — have been developed for separating sludge from the stream of wastewater from a bioreactor. These devices were originally intended for use in microgravity, but have also been demonstrated to function in normal Earth gravity.
NASA Advanced Life Support Systems Group Uses Water Reclamation PrototypeTBMG-228310/01/2007
DynaJets® and DynaSwirl® cavitating jet technologies DynaFlow Jessup, MD 301-604-3688 www.dynaflow-inc.com
Utilization of Aminosilane Antimicrobial Coatings in Spacecraft Potable and Technical Water Systems2007-01-314107/09/2007
Microbial control in spacecraft is currently achieved by environmental control of humidity, forced air filtration, and the use of antimicrobials for surface application (i.e., isopropyl alcohol) and biocidal agents for treatment of potable and technical water supplies (e.g., iodine and iodide or ionic and colloidal silver). Continuous monitoring is required to ensure water quality for shuttle and ISS missions. Water distribution systems for exploration missions on the Crew Exploration Vehicle (CEV) may benefit from a single-application surface-bound antimicrobial coating that limits microbial surface attachment. Consequently, we investigated the use of 3-(trimethoxysilyl) propyldimethyloctadecyl ammonium chloride, a commercially available quaternary aminosilane that bonds permanently to surfaces and inhibits microbial growth. To assess its suitability in spacecraft applications, we previously employed a test method to assess the effectiveness of aminosilane coatings on textiles. This
Hodges, Michael P., Woodard, Daniel, Roberts, Michael S.
Solid-State Viscosity Sensors For Military and Aerospace ApplicationsTBMG-459206/01/2007
Embedded OEM application markets such as the military and aerospace industries are experiencing a growing demand for sensors that provide instantaneous and continuous process control and machine health information. For a large segment of these industries, fluid viscosity is the key physical parameter that can assist in final process control and machine diagnostics. To that end, it is imperative that a solid-state chip be cost-effective and provide the functionality and scalability that is demanded.
Development of Vapor-Phase Catalytic Ammonia Removal SystemTBMG-179405/01/2007
A report describes recent accomplishments of a continuing effort to develop the vapor-phase catalytic ammonia removal (VPCAR) process for recycling wastewater for consumption by humans aboard a spacecraft in transit to Mars. The VPCAR process is implemented by a system of highly integrated design in which some power consumption is accepted as a cost of minimizing the volume and mass of a wastewater-processing system and eliminating the need to resupply water. The core of the system is a wiped-film rotating-disk (WFRD) evaporator, which removes inorganic salts and nonvolatile organic compounds from the wastewater stream and concentrates these contaminants into a recycle-and-bleed stream. The WFRD evaporator is also part of a subsystem that distills water from the wastewater stream. This subsystem operates in a vacuum-vapor/compression distillation configuration in the temperature range from 20 to 65 °C. Volatile organic compounds and ammonia, distilled along with water, are oxidized to
Electrochemical, H2O2-Boosted Catalytic Oxidation SystemTBMG-TB-00080501/03/2007
This system offers several advantages over O2-boosted systems. An improved water-sterilizing aqueous-phase catalytic oxidation system (APCOS) is based partly on the electrochemical generation of hydrogen peroxide (H2O2). This H2O2-boosted system offers significant improvements over prior dissolved-oxygen water-sterilizing systems in the way in which it increases oxidation capabilities, supplies H2O2 when needed, reduces the total organic carbon (TOC) content of treated water to a low level, consumes less energy than prior systems do, reduces the risk of contamination, and costs less to operate. This system was developed as a variant of part of an improved waste-management subsystem of the life-support system of a spacecraft. Going beyond its original intended purpose, it offers the advantage of being able to produce H2O2 on demand for surface sterilization and/or decontamination: this is a major advantage inasmuch as the benign byproducts of this H2O2 system, unlike those of systems
Electroporation System for Sterilizing WaterTBMG-27110/01/2005
A prototype of an electroporation system for sterilizing wastewater or drinking water has been developed. In electroporation, applied electric fields cause transient and/or permanent changes in the porosities of living cells. Electroporation at lower field strengths can be exploited to increase the efficiency of chemical disinfection (as in chlorination). Electroporation at higher field strengths is capable of inactivating and even killing bacteria and other pathogens, without use of chemicals. Hence, electroporation is at least a partial alternative to chlorination.
Removing Pathogens Using Nano-Ceramic-Fiber FiltersTBMG-26505/01/2005
Filters remove greater than 99.9999 percent of viruses and bacteria from wastewater.
Rotating Reverse-Osmosis for Water PurificationTBMG-182706/01/2004
A new design for a water-filtering device combines rotating filtration with reverse osmosis to create a rotating reverse- osmosis system. Rotating filtration has been used for separating plasma from whole blood, while reverse osmosis has been used in purification of water and in some chemical processes. Reverse-osmosis membranes are vulnerable to concentration polarization — a type of fouling in which the chemicals meant not to pass through the reverse-osmosis membranes accumulate very near the surfaces of the membranes. The combination of rotating filtration and reverse osmosis is intended to prevent concentration polarization and thereby increase the desired flux of filtered water while decreasing the likelihood of passage of undesired chemical species through the filter. Devices based on this concept could be useful in a variety of commercial applications, including purification and desalination of drinking water, purification of pharmaceutical process water, treatment of household
Electrochemical, H2O2-Boosted Catalytic Oxidation SystemTBMG-80502/01/2004
An improved water-sterilizing aqueous-phase catalytic oxidation system (APCOS) is based partly on the electrochemical generation of hydrogen peroxide (H2O2). This H2O2-boosted system offers significant improvements over prior dissolved-oxygen water-sterilizing systems in the way in which it increases oxidation capabilities, supplies H2O2 when needed, reduces the total organic carbon (TOC) content of treated water to a low level, consumes less energy than prior systems do, reduces the risk of contamination, and costs less to operate. This system was developed as a variant of part of an improved waste-management subsystem of the life-support system of a spacecraft. Going beyond its original intended purpose, it offers the advantage of being able to produce H2O2 on demand for surface sterilization and/or decontamination: this is a major advantage inasmuch as the benign byproducts of this H2O2 system, unlike those of systems that utilize other chemical sterilants, place no additional
Treatment To Destroy Chloro-hydrocarbon Liquids in the GroundTBMG-119106/01/2003
A relatively simple chemical treatment that involves the use of emulsified iron has been found to be effective in remediating groundwater contaminated with trichloroethylene and other dense chlorohydrocarbon liquids. These liquids are members of the class of dense, non-aqueous phase liquids (DNAPLs), which are commonly recognized to be particularly troublesome as environmental contaminants. The treatment converts these liquids into less-harmful products.
Space Mission Wastewater Recovery System Using Rotating Reverse Osmosis: Process Simulation2002-01-252807/15/2002
Reverse Osmosis (RO) is a compact process for the removal of ionic and organic pollutants from space mission wastewater. However, flux decline and rejection deterioration due to concentration polarization and membrane fouling hinders the application of RO technology. In this study, a rotating cylindrical RO membrane system is investigated as a novel method to reduce concentration polarization for space mission wastewater recovery. The model developed for rotating RO [1] allows the prediction of flux and pollutant rejection over a wide range of design and operation parameters. The model matches the experimental results from a lab-scale rotating RO very well. Operating parameters such as rotational speed and transmembrane pressure play an important role in determining the flux and rejection in rotating RO. A rotational speed sufficient to generate Taylor vortices in the annulus is essential to maintain high flux as well as high rejection. The theoretical energy consumption by rotating RO
Lee, Sangho, Lueptow, Richard M.
Lubricants, Industrial Oils and Related Products -- Type X (Greases) -- SpecificationMS1011_200201 (Historical)01/04/2002
The greases have been classified according to the operating conditions under which they are used, because the versatile nature of greases makes it impractical to classify them according to end use. It will therefore be necessary to consult the supplier to be certain that the grease can be used in, for example, rolling bearings or pumped supply systems, and also concerning the compatibility of products (see Remarks in Table 1). NOTE--In this classification, a grease cannot have more than one symbol. This symbol should correspond to the most severe conditions of temperature, water contamination and load in which the grease can be used.
Fuel and Lubricants TC2 Industrial Lubricants
Enhancing the Removal of Chlorocarbons From GroundwaterTBMG-742409/01/2001
Experiments have shown that ultrasound could be an effective means of enhancing the removal of chlorinated hydrocarbon contaminants from groundwater by the zero-valent-metal treatment process. This process, which has been a subject of research in recent years, is attractive because it does not involve above-ground treatment or the use of pumps, and because the materials needed to effect treatment are safe and relatively inexpensive.
Hybrid Regenerative Water-Recycling SystemTBMG-709302/01/2001
A wastewater-recycling system contains biological and physicochemical water-treatment units. The system is suitable for use in environments in which clean water supplies are limited. Waste streams containing urine and washwater are purified into potable water with a recovery rate of 99 percent. The system includes a two-stage trickling-filter bioreactor, a reverse-osmosis unit, and a photocatalytic post-treatment subsystem. The first stage of the bioreactor reduces the concentrations of organic (carbon-based) compounds, while the second stage removes nitrogen compounds. The effluent from the reactor is sent to the reverse-osmosis unit, which passes 85 percent of the water and diverts the other 15 percent into a concentrated brine. Water is recovered from the brine by evaporation. Finally, the water is treated by ultraviolet light and titanium oxide for disinfection and for oxidation of any organic residue. The system can treat small amounts of very concentrated wastewater, without use
Technique for Controlling Gas Generation in a BioreactorTBMG-699511/01/2000
A pressure-swing technique has been developed for controlling the generation and flow of gas in an anaerobic biological reactor and associated equipment in a system that processes wastewater. The purpose and effect of the technique is to prevent the formation of gas bubbles in the reactor; if allowed to coalesce in the reactor, gas bubbles could impede the flow of the liquid stream, rendering the treatment system less effective. The technique was conceived for application to a wastewater treatment system that would operate in microgravity, but could also be applied to bioreactor systems (e.g., fermentation systems) that operate in Earth-normal gravity.
Water Recovery in Space Development of a Membrane Based Water Treatment Process for Long Range Missions2000-01-238807/10/2000
In the absence of recycling, water represents over 90% of the life-support consumables for a human spacecraft. In addition, over 90% of the waste water generated can be classified as either moderately or slightly contaminated (e.g. shower water, condensate from the air-conditioning system, etc..) The ability to recover potable water from moderately contaminated waste water hence enables significant savings to be made in resupply costs. A development model of such a water-recovery system, based on membrane technology, has been produced and tested using ‘real waste water’ based on used shower water. Results indicate some 95% recovery of potable water meeting European Space Agency (ESA) standards, with total elimination of microbial contaminants such as bacteria, spores and viruses. A second phase focused on improving the functioning of the breadboard and to test it in a long duration test (5-6 months).
Amblard, P., Lasserre, E. C., Lasseur, C., Personne, E. C.
Truck recycling: Environmental-friendly guidelines2000-05-035706/12/2000
Transport is a fundamental aspect of community prosperity and it is closely connected to its development. Transport plays an essential role among the production cycles of a nation, and the commercial vehicle (trucks or buses) makes it possible to become true. From the days when commercial vehicles first appeared, to the early ''80s, main research themes were those intended to increase "productivity" and "profitability." In the ''80s a new and common ecological awareness had induced the industrial sector, and specially motor vehicle manufacturers to try reducing atmosphere and water pollution effects as much as possible. Starting with the ''80s, new needs have appeared in addition to the "usual" ones, entailing entirely new research trends for commercial vehicles. In agreement with Fiat strategies, Iveco made available its know-how, technology and managing capacity, looking for the best and innovative problems created by the birth of vehicles, by their use, and nowadays also by the "end
Montali, Marcello, Fumarola, Massimo
Continuous Electrolytic Generation of Hydrogen PeroxideTBMG-3001511/01/1999
Electrolytic cells for the continuous generation of hydrogen peroxide in streams of water have been developed. Cells of this type could be incorporated into wastewater-treatment systems based on advanced oxidation processes that utilize hydroxyl radicals. In addition to H2O2- generating cells, such a treatment system would include catalysts for the decomposition of H2O2 and the formation of hydroxyl radicals as decomposition products. The hydroxyl radicals would oxidize organic contaminants, thereby removing them from the wastewater.
Electrodialysis To Remove Ammonium Ions From WastewaterTBMG-175909/01/1999
Electrodialysis has been shown to be an effective means for removing ammonium ions from wastewater without use of consumable chemicals and without adding other substances to the treated water. Provided that continuing efforts to develop efficient electrodialysis equipment prove successful, it should be possible to apply this treatment principle to wastewater streams to be recycled in life-support systems for spacecraft and other closed habitats. Effluents from some industrial processes that generate high concentration of ammonium ions may also be treatable by this principle.
Spinach: Nitrate Analysis of an Advanced Life Support (ALS) Crop Cultured Under ALS Candidate Artificial Light Sources1999-01-210707/12/1999
Nitrate concentration in spinach and lettuce is known to be influenced by light quantity. The enzyme nitrate reductase is regulated by phytochrome in some species, and in the presence of light, electrons that reduce nitrite to ammonium come from photosynthetic electron transport. It was hypothesized that light quality as well as light quantity may be used to manipulate nitrate concentration in spinach. To test this, narrow-band wavelength light-emitting diode (LED) sources (670 nm and 735 nm peak emission) were utilized in combination with cool white fluorescent (CWF) lamps. Nitrate concentration was compared in spinach seedlings grown for four weeks under CWF, followed by one of three 5-day pre-harvest light treatments. The three different light quality regimes were 1) CWF, 2) CWF + RED (670 nm) LED, and 3) CWF + FR (735 nm LED). Ion chromatograph analysis of freeze-dried tissue showed a 10-fold increase in nitrate concentration in the CWF+ FR (0.12 mmoles/g dw) treatment over the CWF
Welch, Ross M., Heller, Laurence, Glahn, Raymond P., Johnson, Corinne F., Langhans, Robert W., Albright, Louis D., Combs, Gerald F., Wheeler, Raymond M., Goins, Gregory D.
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