Browse Topic: Water pollution
With the recent rise in electric vehicles and mobile devices, managing spent batteries has become a critical global challenge. By 2040, the number of decommissioned electric vehicles is expected to exceed 40 million, leading to a sharp increase in waste batteries. Developing advanced recycling technologies has thus become an urgent priority, as the metals in batteries pose a significant risk of soil and water contamination.
Inspired by a small and slow snail, scientists have developed a robot prototype that may one day scoop up microplastics from the surfaces of oceans, seas, and lakes. The robot’s design is based on the Hawaiian apple snail (Pomacea canaliculate), a common aquarium snail that uses the undulating motion of its foot to drive water surface flow and suck in floating food particles.
Tracking the spread of COVID-19 through communities provided essential data for public-health officials and individuals to make informed decisions during the pandemic. One method that proved useful was collecting, concentrating, and testing municipal wastewater for the presence of the virus that caused the illness. As this testing ramped up, a technology developed for NASA to identify pathogens inside spacecraft saved time and produced dependable results on Earth.
NASA Kennedy Space Center has developed a water remediation treatment system that utilizes an affordable media that is highly selective for ammonia, allowing large concentrations of ammonia in wastewater to be reduced to levels less than 1 ppm. Following treatment, the media is regenerated for reuse in the system and ammonia is captured as a by-product.
Inspired by a small and slow snail, scientists have developed a robot prototype that may one day scoop up microplastics from the surfaces of oceans, seas, and lakes.
This report describes a preliminary research effort to modify whole effluent toxicity (WET) testing protocols designed for continuous flow discharges for application to episodic and/or ephemeral discharges such as those associated with storm water runoff. The effort was undertaken in response to a Naval Base San Diego industrial stormwater National Pollutant Discharge Elimination System (NPDES) permit (R9-2013-0064) condition that allows the Navy to assess and propose alternative testing parameters. This research (at the time it was conducted) was done for Naval Base San Diego by environmental toxicologists at the Navy’s Space and Naval Warfare Systems Center Pacific (SSC Pacific).
Lubricant additives have a strong influence on the tribological performance of internal combustion engine components, and it is currently one of the leading research driving forces within lubricant companies. However, the anti-friction and anti-wear additives work forming surface tribofilms may have their performance affected by ethanol or water contamination. As both ethanol and water are polar, they may compete on the surface with the additives, avoiding or delaying the additive tribofilm formation. In this work, the effect of ethanol and water on the performance of 4 different fully formulated SAE 0W-20 engine oils, differing only on the friction modifier (FM) additive technology employed, was investigated. In order to emulate fuel dilutions, three tests conditions were carried out for each engine oil: (i) fresh, (ii) in the presence of ethanol, and (iii) in the presence of ethanol and water. Friction and wear of actual piston ring and liner were evaluated in a reciprocating test designed to emulate actual thermomechanical conditions of both urban and highway car use. Amine and ester FM containing engine oils did not show a significant difference in friction in the fresh condition of the hot-running phase. However, with ethanol and water, amine and ester FM oils provided 30% and 20% friction reduction on the contact, respectively. In its fresh condition, molybdenum type FM-containing oil reduced the CoF (71%) drastically, and even worsening its performance with the ethanol and water dilutions, molybdenum-containing oil still kept a high level of CoF reduction when compared with the baseline oil and the other friction modifiers. The wear of the cylinder liner and piston ring was low, not being affected by the oil dilutions. Those results evidence that somehow the friction modifier performance, nowadays of utmost importance to achieve targets of fuel economy, is affected by the presence of ethanol and water in the lubricant, and the level of influence depends upon temperature and the formulation technology applied.
Army-funded research identified a new chemistry approach that could remove micropollutants from the environment. Micropollutants are biological or chemical contaminants that make their way into ground and surface waters in trace quantities.
Among the many avenues that viruses can use to infect humans, drinking water may pose only a tiny risk for spreading certain viruses like the novel coronavirus. But in cases where there is unauthorized wastewater disposal or other events of inadvertent mixing of wastewater with water sources, the possibility of transmission through drinking water remains unknown.
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 Savannah River National Laboratory (SRNL) — located in Aiken, SC — is the applied research and development laboratory at the U.S. Department of Energy's (DOE) Savannah River Site (SRS). The laboratory applies state-of-the-art science to provide practical, high-value, cost-effective solutions to complex technical problems. SRNL technologies are used to detect weapons of mass destruction, clean up contaminated groundwater and soil, develop hydrogen as an energy source, support the need for a viable national defense, and safely manage hazardous materials.
NASA has invented an innovative method to grow algae, clean wastewater, and capture carbon dioxide to ultimately produce biofuel. The invention consists of floating flexible-plastic enclosures and photo-bioreactors with semi-permeable membranes. This new cultivation system is made of lightweight material and is deployed offshore, avoiding the problems of land costs and competition with other land uses. The surrounding waters provide infrastructure, cooling, and some mixing from wave action. Ideally, this cultivation system is filled with nutrient-rich domestic wastewater and a source of CO2 to promote the growth of algae and to remediate pollution.
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 workers (self-employed and employees) in agriculture and forestry who suffer in India. In this project work, the challenge was to predict vibration performance / characteristics of 8 HP, 2100 rpm, single cylinder diesel engine. Also check the effect of up-gradation of same engine to 2600 rpm; which will be done to get more water quantity and at higher level /head. Engine model building was started with 3D CAD modeling using Pro/E software then discritization (Meshing) and Nastran solver deck / model with loads and boundary conditions was developed using Hyper Mesh software. Engine loads was calculated using analytical methods for 2100 rpm & 2600 rpm. Those excitation loads was used to simulate NVH behavior of engine using CAE method. Detailed vibration source identification was carried out by actual vibration measurement using B & K measuring system and NVH CAE simulation methods. Fuel tank and gear cover was potential candidate of vibration. Based on vibration source identification by both methods, design modifications were done and verified using NVHCAE simulation technique for 2100 rpm and 2600 rpm before final recommendation for design changes. Those modifications were showing good amount of vibration reduction for the respective natural frequencies as design changes were strengthening the plane surfaces of sheet metal fuel tank and gear cover. Design modifications were recommended to implement after prototype testing.
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 analyzed. Based on the analysis, the design of the post-process of ice melting was modified. After determining the layout scheme of microwave steam deicing device on vehicles, the analysis energy flow of vehicle was completed in the last. The result shows that the deicing vehicle is viable and its energy consumption is eighty percent as much as the traditional deicing vehicle's for melting the 5mm thin ice layer. There is no water pollution and road surface damage in the whole process.
Effective recovery of potable water from various streams and sources of wastewater, seawater, or contaminated water is a significant task for securing existence of human beings in space, terrestrial, and marine environments. Efficient purification of the wastewater is also a very important task for protection of the global environment. The existing and known methods of recovery of clean water from the wastewater are technically complicated, have low energy efficiency, consume processing material, and are bulky, heavy, and not cost effective.
When not disposed properly, the frying oil from the household or restaurants may cause clogging of waste drainage pipes and sewage systems, water contamination and soil sealing. The production of biodiesel from frying oil and its utilization for energy generation is a potential alternative to disposal, adding value to this waste and using it as an energy source. This article presents a case study of a proposal to produce biodiesel from frying oil for fuel up vehicles used to the employees transport inside Fiat's plant in Betim, Brazil. Besides the technical and economic evaluation, a life cycle assessment (LCA) was performed to examine the environmental viability of producing the biodiesel from cooking oil and its use for fuel up the minibuses replacing conventional diesel B5 for B50.
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 novel Fuel Dehydrating Icing Inhibitors (FDII). This paper describes our systematic approach towards the development of jet fuel additives which are kinetically fast, selective, lipophilic water scavengers that produce, upon hydrolysis, a hydrophilic ice inhibitor. A brief human and environmental toxicological screening of candidates is described. We anticipate that this class of FDII represents a novel approach towards protecting jet fuel against the effects of water contamination.
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 back-pressure valve failure. Upon closing the back-pressure valve and energizing the pump, the ice eventually thawed and water began to flow with no apparent damage to the sheet membrane.
A flex fuel engine is capable of operating efficiently on any combination of gasoline and ethanol. However, an engine combustion strategy must adapt quickly to a change in ethanol concentration after a refueling event in order to achieve optimum engine combustion. Typical control systems rely on an exhaust gas oxygen sensor (lambda) to measure changes in oxygen concentration following combustion. This feedback control approach can take five to ten minutes to detect the fuel change and correct the combustion strategy. This relatively long lag time could result in suboptimal engine performance such as a loss of engine power, engine knocking, poor cold start performance, unburned hydrocarbons, and high pollutant emissions. To counter this shortcoming, an on-board flex fuel sensor (FFS) was developed to enable a feed-forward control strategy. The FFS may be installed inline between the fuel tank and fuel injector and measure the fuel prior to it reaching the injector. The FFS sensor estimates the concentration of ethanol in the fuel in real-time using a correlation based on permittivity, conductivity, and temperature of the fuel flowing through the sensor. The FFS is specifically designed for the Brazilian market and is calibrated to measure the anhydrous ethanol and hydrous ethanol contained in gasohol and alcohol respectively. The sensor can accurately estimate the total ethanol concentration (anhydrous plus hydrous) within +/− five volume percent for any combination of gasohol and alcohol. The sensor can operate with a fuel temperature range of −40°C to 95°C. In addition, the FFS provides diagnostic capability and is able to identify and report water contamination to the engine control module.
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.
In the competitive market of the car industry today, companies need to continuously strive to optimize the performance, price and environmental properties of their products in order to survive. Wet clutches, as parts of transmission components of passenger cars are no exception. An understanding of how the wet clutch system functions and fails is necessary to optimize price and service life. The friction characteristics of the wet clutch system are determined by lubricant-surface interactions in the contact between the friction discs. Wet clutch failure can often be associated with the deterioration of friction characteristics which eventually leads to stick-slip or shudder. Consequently, knowledge of why and of how friction characteristics change over time is of the outermost significance to enable the understanding and prediction of wet clutch performance. As the lubricant is an essential component of the wet clutch system, lubricant ageing is a factor of importance. Oxidation, thermal degradation, shearing, additive degradation and water contamination could all be considered to influence lubricant ageing. The aim of this work was therefore to find suitable ways of measuring the remaining useful life of wet clutch lubricants and to correlate changes in friction characteristics with changes in lubricant properties. Both field trials and measurements in a wet clutch test rig were performed. Viscosity, acid number, additive degradation, water contamination, particle content and metal content were measured for the lubricant as it degraded. Particle content results showed a rapid increase early in the ageing process. However, as ageing progressed particle levels actually decreased and this was probably a result of particles slowly grinded between contacting surfaces. On the other hand, metal content increased as ageing progressed, which could indicate slowly progressing wear. Water levels were found to be higher in field trials than in lubricants used in wet clutch test rigs. It is concluded that this was due to the severe and accelerated operating conditions of the wet clutch test rig.
As a potential source of food for long-duration space missions, space-grown plants could give astronauts an important psychological boost, as fresh vegetables could serve as a welcomed change from reconstituted foods in plastic bags. Even more, these plants could likely aid in the recycling of air and wastewater on spacecraft.
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.
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.
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