Browse Topic: Land pollution

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Methods for Purifying Enzymes for MycoremediationTBMG-268575/1/2017
This process applies to remediation and restoration of soils contaminated by fuel, polychlorinated biphenyl wastes, etc. While there can be a general beneficial effect of microbial communities, individual plant-fungus combinations can vary in their efficacy in removal of pollutants from the environment. Selection of the most effective combination of plants and fungi is very important for achieving the desired benefits. Not all fungi are created equal, as some die off in contaminated soils. Having a set of enzymes from fungi specifically adapted to conditions in contaminated soils and use of native plant/fungal combinations is a huge advantage. Ectomycorrhizal (EM) mediated remediation of phenolic-based contamination through use of specifically adapted soil and enzymes utilizes plant/fungal combinations that are specifically adapted to conditions created by phenolic application to soils, and the abilities of EM fungi to oxidize these compounds. This platform can be adapted to other ecosystems through field assessments of the EM community in each new site.
MMT Effects on Gasoline Vehicles: A Literature Review2016-01-90733/14/2016
Methylcyclopentadienyl manganese tricarbonyl (MMT) is an octane-boosting gasoline additive that has been used for over 50 years. This usage has been controversial; particularly in modern gasoline vehicles equipped with advanced emissions control systems. There is concern that extended use of MMT will lead to build-up of Mn-containing deposits on engine and emissions system components, thereby adversely affecting vehicle emissions performance and durability. This paper provides a comprehensive review of the literature regarding the effects of MMT on gasoline vehicles, with an emphasis on modern, Tier 2 vehicles. Numerous test programs have been conducted - including wide ranges of vehicle model years, technology types, and testing conditions. The reported MMT effects over this body of literature are not consistent. In general, studies by automakers have concluded that under certain test conditions, use of MMT is detrimental; contributing to catalyst plugging, deteriorated performance, and increased emissions. In contrast, most studies by Ethyl/Afton have concluded that under typical operating conditions, use of MMT does not cause harm, and does not contribute to exceedances of vehicle emissions standards. These opposing conclusions can be attributed largely to two factors: (1) differences in test cycles/conditions and (2) the basis for emissions comparisons. To achieve compliance with stringent Tier 2 emissions standards, automakers have adopted more active catalysts having higher cell densities, higher surface areas, and thinner cell walls. Furthermore, these catalysts are mounted in configurations that are close coupled (CC) to the exhaust manifold, promoting more rapid initial heating and higher overall catalyst temperatures. These technology enhancements have increased concerns about the use of MMT. There is credible evidence that under certain in-use operating conditions, MMT has contributed to catalyst plugging in Tier 2 vehicles. Similar concerns are expected to apply to future Tier 3 technology vehicles.
Hoekman, S. Kent, Broch, Amber
Using Iron To Treat Chlorohydrocarbon Contaminated SoilTBMG-67010/1/2004
A method of in situ remediation of soil contaminated with chlorinated hydrocarbon solvents involves injection of nanometer-size iron particles. This method should not be confused with a similar method, involving injection of emulsified iron particles, reported in “Treatment To Destroy Chlorohydrocarbon Liquids in the Ground” (KSC-12246), NASA Tech Briefs, Vol. 27, No. 6 (June 2003), page 56. Like that method, this method is implemented in a process that is safe, yields environmentally benign end products, takes less time and costs less than do traditional pump-and-treat processes, and is both less expensive and less environmentally disruptive than are cleanup processes that involve excavation, trans-port to facilities for incineration or other treatment, and reburial
Electrokinetic In Situ Treatment of Metal-Contaminated SoilTBMG-8041/1/2004
An electrokinetic technique has been developed as a means of in situ remediation of soils, sludges, and sediments that are contaminated with heavy metals. Examples of common metal contaminants that can be removed by this technique include cadmium, chromium, zinc, lead, mercury, and radionuclides. Some organic contaminants can also be removed by this technique.
Trend of Regulation in Korea & Introducing Activities of Renault Samsung Motors for Recycling2003-01-288110/27/2003
The status of recycling in Korea was reviewed, including the status of ELV(End-Life-Vehicle) and activities of the recycling industry. Also the Korean regulation for recycling was explained, focusing the unique system of Korea. Hereby, the unique system means that all the car makers have to summit the report which shows their activity of the design improvement for recycling to the government in annual year. Finally, the development items and contents was introduced, which RSM(Renault-Samsung Motors) are tackling. These items were selected on the basis of Renault-Nissan Alliance's policy which promotes increasing recycle rate and eliminating the hazardous materials.
Kim, Sun-Woong, OONO, Masashi
Electrometer for Triboelectric Evaluation of MaterialsTBMG-26324/1/2002
An electrometer developed for measuring the triboelectric responses of soils on Mars is also potentially useful on Earth for identifying some materials via their triboelectric responses. In operation, an array of triboelectric sensors is rubbed against the material of interest for a predetermined distance, then withdrawn from the material of interest at a predetermined speed. During this operation, the electrometer circuitry measures the time-varying sensor output voltages, which are proportional to the electric charges induced on the sensors by the rubbing. The resulting voltage-vs.-time data constitute the desired triboelectric-response data. If materials that one seeks to identify or to distinguish from each other exhibit unique, known triboelectric responses that have been catalogued, then a sample of unknown material can be identified by seeking a match between its triboelectric response and one of the catalogued responses.
Testing Soil for Electrokinetically Enhanced BioremediationTBMG-30312/1/2002
The term “prefield test” denotes an in situ test of contaminated soil in preparation for in situ treatment of the soil by a method called “electrokinetically enhanced bioremediation” (EEB). A prefield test yields data that are helpful in designing and operating an efficient and cost-effective EEB system.
Engineered Bioremediation of Contaminated SoilTBMG-73877/1/2001
Electrokinetically enhanced bioremediation (EEB) is a method of engineered bioremediation of soil contaminated by such organic compounds as solvents and petroleum products. As depicted schematically in the figure, EEB involves the utilization of controlled flows of liquids and gases into and out of the ground via wells, in conjunction with electrokinetic transport of matter through pores in the soil, to provide reagents and nutrients that enhance the natural degradation of contaminants by indigenous and/or introduced micro-organisms.
Simple Mathematical Models for Estimating the Bio-Contamination Transported from a Lander or a Rover to the Martian Soil2000-01-24227/10/2000
To enable reliable in situ, or sample return, life detection missions, it is critical that Mars missions be free of any biological materials that originated from Earth and could contaminate samples collected for analysis. Therefore, it is important that likely cross-contamination mechanisms be thoroughly studied and understood. Three simple models have been developed to estimate the maximum soil contamination that could originate from a bio-contaminated lander. All three models estimate the ground contamination concentrations at various distances from the lander. The first model estimates the ground concentration if the microorganisms covered the soil 360° around the lander. The second model uses a steady state Gaussian plume to transport the microorganisms from the Lander. The third model determines the ground contamination level from an instantaneous Gaussian puff release, probably at the time of landing. Input to the models includes the total spacecraft (s/c) contamination level, the height of the lander, the size distribution of the particles and their microbial burden, the fraction of the total contamination that is removed, the wind speed, and the diffusivities of the plumes. The results are given for input data available from old studies performed at the Kennedy Space Center. More realistic data are now being obtained at JPL.
Beaudet, Robert A.
LCI/LCA as Part of an Integrated Management System in the Steel Industry1999-01-03543/1/1999
Under the aspect of a sustainable economic production the constantly increasing demands placed on an environmentally-friendly product with regard to quality and price shall be connected with each other. In order to achieve this goal, attempts based on the previous environmental performance of the company have been made to further develop environmental protection in the plant facilities: the core of this development is the integration of the existing management systems as well as the implementation of a comprehensive environmental audit. The recording and evaluation of environmental effects was done in a way which - owing to an expansion of the area under investigation - allows to carry out an LCA of our main products.
Weismayr, Christian, Pammer, Klaus
Particle Size Distribution Downstream Traps of Different Design9503732/1/1995
High levels of particulate emissions from Diesel engines, in tunnel construction sites, force the aftertreatment of exhaust gases with particulate traps. Sub-micron particulates are suspected to be carcinogenic. Hence, the size distribution of particulates was compared for different particulate trap systems. The two extreme types are the ceramic monolith surface filter and the typical deep-bed filter of knitted fiber. These two types have distinctly different properties. The gravimetric evaluation of both systems show comparable efficiencies around 90%. If, instead, the particle count is evaluated: the efficiency of the surface filter drops below 70%, whereas that of the deep-bed filter increases. The spectral analysis of distinct solid particulates shows that the efficiency of the surface filter deteriorates for particles smaller than 100 nm. The toxicological consequences are disquieting.
Burtscher, H., Czerwinski, J., Gehrig, D., Egli, H., Mayer, A.
An Electronic, Environmental Monitoring System for Water-Borne Contaminants with Control for Irrigation Machines9324259/1/1993
A small, field-scale system has been developed to assess the feasibility of controlling irrigation machine applications by use of an in-situ environmental monitoring system. Presently, the system monitors soil moisture in the root zone by use of Watermark sensors. Development is underway for a soil nitrate sensor. The completed system will monitor soil moisture, plant nutrients and pesticides. Remote, solar-powered sensors periodically update data in a central computer program. The program is being designed to track pollutant concentration and movement in a watershed, control spatial application of large irrigation machines or provide remediation monitoring for federal laboratory sites.
Halderson, James L., Goodyear, Jack D.
Lockheed Adopts Media Blast Dry Stripping for the C-1309209494/1/1992
Raffaele, Robert, Pauli, Robert
The Characterization of the Soluble Organic Fraction of Diesel Particulate Matter7904182/1/1979
This paper is concerned with the demonstration of a methodology for chemically characterizing diesel particulate organic matter (POM) emissions. The procedure begins with a Soxhlet extraction of the POM with dichloromethane to obtain a soluble organic fraction (SOF). The acidic and basic portions of the SOF are isolated by liquid-liquid extraction techniques with aqueous base and aqueous acid, respectively. The neutral portion of the extract is separated into paraffin, aromatic, transitional and oxygenated fractions by column chromatography on silica gel. Two additional fractions, the ether insoluble and hexane insoluble fractions, are also separated by the procedure. Quantitative mass data are presented on the extraction and fractionation of twelve particulate samples from the exhaust of a medium-duty diesel engine collected in a dilution tunnel at a volume dilution ratio of 8 to 1. Three fuels with a range of properties and two steady-state engine conditions from the EPA 13 Mode Cycle were used as experimental variables in this study.
Funkenbusch, Eric F., Leddy, David G., Johnson, John H.
Ecologic Ramifications of Air Pollution7206302/1/1972
Pollutants are emitted into the atmosphere by both industrial and natural processes. Natural processes also remove these pollutants from the atmosphere, but when total emissions exceed the capacity of natural sinks, the quality of the air decreases. Air pollution can cause severe damage to plants, animals, and microorganisms. Air pollution can also cause subtle damage to the biosphere, as manifested by growth retardation, acceleration of aging processes, alterations in reproductive potential and genetic constitution, and alterations in host-parasite relations. However, air pollutants may serve some beneficial roles, such as satisfying some nutrient requirements of plants. Field studies, however, indicate that the environment, in general, is adversely affected by atmospheric pollution. Unfortunately, only speculations on ecologic ramifications of air pollution are possible with the present level of knowledge.
Babich, Harvey, Stotzky, Guenther
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