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1.
Commodore Solution Technologies, Inc. has developed an innovative total systems approach to environmental remediation that utilizes a patented chemistry called Solvated Electron Technology (SETTM). Solvated electron solutions are some of the most powerful reducing agents know. Formed by dissolving alkali and alkaline-earth metals in anhydrous liquid ammonia to produce a solution of metal cations and free electrons, solvated electron solutions are capable of providing reductants of great activity and uniqueness. They provide a highly useful mechanism for the reductive destruction of many organic molecules and are extremely effective in the dehalogenation of halogenated organic compounds. Commodore has received a nation-wide EPA operating permit for the nonthermal destruction of PCBs using this process. The SoLVTM process is a total solution approach that incorporates SETTM with pre-and post-treatments, when necessary, for environmental cleanup. It is applicable to a broad range of substrates including liquids, solids, soils, and job materials. This article presents results from several pilot, field, and commercial validation studies utilizing the SoLVTM process.  相似文献   

2.
Ohmsett – the National Oil Spill Response Test Facility, is the world's largest tow/wave tank designed to evaluate the performance of equipment that detects, monitors and clears up oil spills under environmentally safe conditions. Ohmsett is the only facility capable of testing and training with oil, using full-scale response equipment.  相似文献   

3.
Vapor intrusion characterization efforts can be challenging due to complexities associated with background indoor air constituents, preferential subsurface migration pathways, and response time and representativeness limitations associated with conventional low‐frequency monitoring methods. For sites experiencing trichloroethylene (TCE) vapor intrusion, the potential for acute risks poses additional challenges, as the need for rapid response to exposure exceedances becomes critical in order to minimize health risks and associated liabilities. Continuous monitoring platforms have been deployed to monitor indoor and subsurface concentrations of key volatile constituents, atmospheric pressure, and pressure differential conditions that can result in advective transport. These systems can be comprised of multiplexed laboratory‐grade analytical components integrated with telemetry and geographical information systems for automatically generating time‐stamped renderings of observations and time‐weighted averages through a cloud‐based data management platform. Integrated automatic alerting and responses can also be engaged within one minute of risk exceedance detection. The objectives at a site selected for testing included continuous monitoring of vapor concentrations and related surface and subsurface physical parameters to understand exposure risks over space and time and to evaluate potential mechanisms controlling risk dynamics which could then be used to design a long‐term risk reduction strategy. High‐frequency data collection, processing, and automated visualization efforts have resulted in greater understanding of natural processes such as dynamic contaminant vapor intrusion risk conditions potentially influenced by localized barometric pumping induced by temperature changes. For the selected site, temporal correlation was observed between dynamic indoor TCE vapor concentration, barometric pressure, and pressure differential. This correlation was observed with a predictable daily frequency even for very slight diurnal changes in barometric pressure and associated pressure differentials measured between subslab and indoor regimes and suggests that advective vapor transport and intrusion can result in elevated indoor TCE concentrations well above risk levels even with low‐to‐modest pressure differentials. This indicates that vapor intrusion can occur in response to diurnal pressure dynamics in coastal regions and suggests that similar natural phenomenon may control vapor intrusion dynamics in other regions, exhibiting similar pressure, geochemical, hydrogeologic, and climatic conditions. While dynamic indoor TCE concentrations have been observed in this coastal environment, questions remain regarding whether this hydrogeologic and climatic setting represent a special case, and how best to determine when continuous monitoring should be required to most appropriately minimize exposure durations as early as possible. ©2017 Wiley Periodicals, Inc.  相似文献   

4.
Vapor intrusion characterization efforts are challenging due to complexities associated with indoor background sources, preferential subsurface migration pathways, indoor and shallow subsurface concentration dynamics, and representativeness limitations associated with manual monitoring and characterization methods. For sites experiencing trichloroethylene (TCE) vapor intrusion, the potential for acute risks poses additional challenges, as the need for rapid response to acute toxicity threshold exceedances is critical in order to minimize health risks and associated liabilities. Currently accepted discrete time‐integrated vapor intrusion monitoring methods that employ passive diffusion–adsorption and canister samplers often do not result in sufficient temporal or spatial sampling resolution in dynamic settings, have a propensity to yield false negative and false positive results, and are not able to prevent receptors from acute exposure risks, as sample processing times exceed exposure durations of concern. Multiple lines of evidence have been advocated for in an attempt to reduce some of these uncertainties. However, implementation of multiple lines of evidence do not afford rapid response capabilities and typically rely on discrete time‐integrated sample collection methods prone to nonrepresentative results due to concentration dynamics. Recent technology innovations have resulted in the deployment of continuous monitoring platforms composed of multiplexed laboratory grade analytical components integrated with quality control features, telemetry, geographical information systems, and interpolation algorithms for automatically generating geospatial time stamped renderings and time‐weighted averages through a cloud‐based data management platform. Automated alerts and responses can be engaged within 1 minute of a threshold exceedance detection. Superior temporal and spatial resolution also results in optimized remediation design and mitigation system performance confirmation. While continuous monitoring has been acknowledged by the regulatory community as a viable option for providing superior results when addressing spatial and temporal dynamics, until very recently, these approaches have been considered impractical due to cost constraints and instrumentation limitations. Recent instrumentation advancements via automation and multiplexing allow for rapid and continuous assessment and response from multiple locations using a single instrument. These advancements have reduced costs to the point where they are now competitive with discrete time‐integrated methods. In order to gain more regulatory and industry support for these viable options, there is an immediate need to perform a realistic cost comparison between currently approved discrete time‐integrated methods and newly fielded continuous monitoring platforms. Regulatory support for continuous monitoring platforms will result in more effectively protecting the public, provide property owners with information sufficient to more accurately address potential liabilities, reduce unnecessary remediation costs for situations where risks are minimal, lead to more effective and surgical remediation strategies, and allow practitioners to most effectively evaluate remediation system performance. To address this need, a series of common monitoring scenarios and associated assumptions were derived and cost comparisons performed. Scenarios included variables such as number of monitoring locations, duration, costs to meet quality control requirements, and number of analyses performed within a given monitoring campaign. Results from this effort suggest that for relatively larger sites where five or more locations will be monitored (e.g., large buildings, multistructure industrial complexes, educational facilities, or shallow groundwater plumes with significant spatial footprints under residential neighborhoods), procurement of continuous monitoring services is often less expensive than implementation of discrete time‐integrated monitoring services. For instance, for a 1‐week monitoring campaign, costs‐per‐analysis for continuous monitoring ranges from approximately 1 to 3 percent of discrete time‐integrated method costs for the scenarios investigated. Over this same one‐week duration, for discrete time‐integrated options, the number of sample analyses equals the number of data collection points (which ranged from 5 to 30 for this effort). In contrast, the number of analyses per week for the continuous monitoring option equals 672, or four analyses per hour. This investigation also suggests that continuous automated monitoring can be cost‐effective for multiple one‐week campaigns on a quarterly or semi‐annual basis in lieu of discrete time‐integrated monitoring options. In addition to cost benefits, automated responses are embedded within the continuous monitoring service and, therefore, provide acute TCE risk‐preventative capabilities that are not possible using discrete time‐integrated passive sampling methods, as the discrete time‐integrated services include analytical efforts that require more time than the exposure duration of concern. ©2016 Wiley Periodicals, Inc.  相似文献   

5.
Cost estimates are frequently developed to evaluate hazardous‐waste‐site cleanup options in support of a site investigation, remedy selection decision, or assessment of environmental liabilities. The accuracy of the cost estimate depends largely on the quality of the information available at the time it is prepared. This article presents a practical guide to developing a cleanup cost estimate. It includes information on how to document assumptions, use the latest technical resources, and perform basic adjustments to account for uncertainty and the time value of money. The content is based upon a recent guidance document issued by the U.S. Environmental Protection Agency and U.S. Army Corps of Engineers entitled A Guide to Developing and Documenting Cost Estimates during the Feasibility Study (USEPA, 2000). © 2001 John Wiley & Sons, Inc.  相似文献   

6.
Sustainable material management (SMM) has been initiated by the Organization for Economic Cooperation and Development (OECD) in 2005. SMM is an approach to promote resource conservation, reducing negative environmental impacts and preserving the natural capital of material and the balance of economic efficiency and social equity. Life cycle assessment and material flow analysis have been widely used to estimate the environmental impacts for resource consumption, but economic development has not been taken into account. Before 1984, improper garbage disposal was not an important issue in Taiwan. But over the past three decades, the Taiwan Government has accomplished not only waste disposal but also resource recycling, which are conducive to the essence of SMM. This study is the first research project to develop a SMM conceptual model for policy and strategy in Taiwan. SMM is the suitable waste management concept for the next era. This study reviewed the policy and strategy that has been applied in Taiwan’s waste management, and compares the efficiency of waste management policy in Taiwan with the concept of SMM. A case study of the waste flow will be used to prove that the sustainable material policy can be a suitable management system to achieve sustainable development. This study will open a new chapter of research on global SMM for Taiwan.  相似文献   

7.
The substance class of inert organic-chemical stressors (IOCS) describes organic-chemical (macro-) molecules, which demonstrate a high level of persistence upon entry in the ecosystem, and whose degradation is limited. These synthetically produced organic-chemical macromolecules, which are often derived from the polymerization of different monomers, are, in the form of plastics, indispensable in the everyday world. They enter the environmental compartments and cause great damage due to primary (industry, cosmetic, washing of textile), and secondary (degradation) entry. If these particles get into aquatic systems, this has fatal consequences for the ecosystem such as the death of marine animals, or bioaccumulation. Wastewater treatment plants are reaching their limits and require innovative ideas for the sustainable removal of microplastic. This article examines a new approach to the removal of polymers from aquatic systems (lab scale) by using sol–gel induced agglomeration reactions to form larger particle agglomerates. These enlarged agglomerates can be separated much more easily from the wastewater, since they float on the water surface. Separation systems, e.g. sand trap can easily be used. A further advantage is that the agglomeration can be carried out completely independently of the type, size, and amount of the trace substance concentration as well as of the external influences (pH value, temperature, pressure). Thus, this new type of particle separation can not only be used in sewage treatment plants, but can also be transferred to decentralized systems (e.g. implementation in industrial processes).

Graphical Abstract

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8.
Journal of Material Cycles and Waste Management - Global waste production is pegging at unforeseen heights and alarming for its sustainable management. Information and Communication Technologies...  相似文献   

9.
Reviews including the latest “data‐rich” chemical vapor intrusion‐radon (CVI‐Rn) studies indicate buildings/times can be “screened‐in” as having Rn‐evident‐susceptibility/priority for soil gas intrusion, and elevated‐potential for CVI concerns, or not. These screening methods can supplement conventional indoor‐air chemical sampling, under naturally varying conditions, by prioritizing buildings and times based on indoor Rn levels. Rn is a widespread, naturally occurring component of soil gas and a tracer of soil gas intrusion into the indoor air of overlying buildings. Rn is also an indicator for generally similar behavior of other components of near‐building soil gas, possibly including chemical contaminant vapors. Indoor Rn is easily measured at a low cost, allowing continuous observations from essentially all buildings with the potential for CVI across time. This presents cost savings and other benefits for all CVI stakeholders.  相似文献   

10.
Over the past few years, the focus of our research has been to respond to the recognized needs for novel biological processes that are capable of destroying a wide range of biodegradable pollutants and providing the perfect environment for complex interspecies interactions required for the degradation of environmental contaminants. A new biotechnology process called Biological Permeable Barrier (BPB) was developed to provide high microbial density, stable environmental conditions, and protective measures for microbial activities for in‐situ bioremediation of contaminated groundwater. This patented technology (U.S. Patent 6,337,019 ) is based on the creation of a structured matrix, or Bio‐beads, that provides the perfect environment for organic‐degrading microorganisms to establish biofilms capable of destroying the contaminants in water with remarkable stability and control. For over 240 days, the viability and performance of the BPB (Bio‐beads) system were shown for biodegradation of a targeted contaminant, 2,4,6‐ trichlorophenol (TCP), under a variety of operating and stress conditions (Razavi‐Shirazi, 1997 ). Extensive batch experiments were also conducted to obtain necessary data to determine the rate of TCP diffusion into the Bio‐beads, adsorption properties of the Bio‐beads, and substrate‐use rate of the mixed bioculture as free cells and as immobilized cells (Bio‐beads). A simulated model of BPB was also characterized with its porosity, permeability, and compressibility or deformation under typical field conditions. Our extensive research showed that BPB takes advantage of a controlled biotechnology process to overcome the disadvantages and uncertainties associated with conventional biological processes. A summary of our investigation is presented here. © 2002 Wiley Periodicals, Inc.  相似文献   

11.
The growing interest in bio-polymers as a packaging material, particularly from companies looking to reduce their environmental footprint, has resulted in wider adoption. Traditionally the selection and specification of packaging materials was based on aesthetic, technical and financial factors, for which established metrics exist. However with bio-polymers, where the primary rationale for their use is environmental, alternative metrics are required. Furthermore, there is a significant strategic element to the decision process that requires a broader range of horizontal and vertical inputs, both within the business and the wider supply chain. It is therefore essential that a holistic approach is taken to the bio-polymer based packaging design process to ensure that the final packaging meets the original strategic intent and overall requirements of the business. Current eco-packaging design tools are generally limited to professional users, such as designers or packaging engineers, and generally provide tactical rather than strategic support. This disconnect, between the need for inclusivity and greater strategic support in holistic design, and the exclusivity and largely tactical support of current eco-design support tools, indicates a clear need for a new decision support tool for sustainable pack design using bio-polymers. This paper proposes a framework for an eco-design decision support tool for bio-polymer based packaging that has been developed using a predominantly qualitative research approach based on reviews, interviews and industrial packaging design experience and is an extension of previously published work. This research investigates further how existing eco-design methods, such as the ‘Balanced Score Card’, can be applied within the tool and how the shortcomings associated with incorporating social and environmental aspects can be partly resolved, through a simplified set of metrics tailored specifically for bio-polymer packaging decisions. The results of this research is a framework for the development of a three tier eco-design tool for bio-polymer packaging that provides decision support at the three critical stages of the design process: strategic fit, Feasibility assessment and concept/pack development.  相似文献   

12.
Thin sediment capping is a commonly used technique to prevent mobilization of contaminants from sediments into the environment. A 70‐m‐deep subaqueous confined disposal facility (CDF, 350,000 m2) at Malmøykalven, Oslofjord, which received dredged contaminated sediments from Oslo Harbor, was capped with 148,900 m3 of sand in 2009. This research serves as a case study regarding some of the key considerations involved with the cap placement and monitoring of the cap layer. Uncertainty is included in all the cap thickness monitoring methods and a combined use of them provided a better understanding of the cap coverage and structure at the site. An open water disposal model (STFATE) was used to simulate the behavior of the barge‐released cap material. The modeling results were consistent with field observations regarding the material spread, and the results provided insight into the relatively high material losses calculated. Better knowledge obtained of material settling resulted in cap properties and cap monitoring methods that are useful when planning similar operations. ©2015 Wiley Periodicals, Inc.  相似文献   

13.
Advances in computing processing power and in availability of environmental and biological data have allowed the development and application of comprehensive modeling systems that utilize a holistic, integrated, approach for assessing the interactions of environmental and biological systems across multiple scales of spatiotemporal extent and biological organization. This approach allows mechanism-based environmental health risk assessments in a person-oriented framework, which accounts for simultaneous exposures to contaminants from multiple media, routes, and pathways. The conceptual basis and example applications of the Modeling ENvironment for TOtal Risk (MENTOR), and the DOse–Response Information ANalysis system (DORIAN) are presented.  相似文献   

14.
Journal of Polymers and the Environment - The current scenario of global trends impacts the way in which food is consumed and packed, meaning that change is inevitable and just around the horizon...  相似文献   

15.
Pet Waste Management by Chemical Recycling: A Review   总被引:1,自引:0,他引:1  
The paper reviews the problem due to the use and disposal of synthetic polymers to the environment and its solutions; in particular poly (ethylene terphthalate). Wide spread application and non-biodegradability of the PET creates huge amounts of waste and disposal, tend to a serious problem. The most important cause for recycling and reprocessing the waste PET has arisen from the awareness and concern for environmental pollution. To manage this various methods of polymer recycling has been proposed. Among them chemical recycling, i.e. hydrolysis, methanolysis, glycolysis and aminolysis are reviewed in detail. Appropriate technology and waste disposal procedures based on the socio-economic aspect to solve this problem are suggested.  相似文献   

16.
We discuss the background and methods for estimating uncertainty in a holistic manner in a regional terrestrial biota Full Carbon Account (FCA) using our experience in generating such an account for vast regions in northern Eurasia (at national and macroregional levels). For such an analysis, it is important to (1) provide a full account; (2) consider the relevance of a verified account, bearing in mind further transition to a certified account; (3) understand that any FCA is a fuzzy system; and (4) understand that a comprehensive assessment of uncertainties requires multiple harmonizing and combining of system constraints from results obtained by different methods. An important result of this analysis is the conclusion that only a relevant integration of inventory, process-based models, and measurements in situ generate sufficient prerequisites for a verified FCA. We show that the use of integrated methodology, at the current level of knowledge, and the system combination of available information, allow a verified FCA for large regions of the northern hemisphere to be made for current periods and for the recent past.  相似文献   

17.
Journal of Polymers and the Environment - This work was the first to reveal structural and thermal characteristics of biomass lignins obtained from Thai agricultural residues; bagasse (BG),...  相似文献   

18.
19.
A pilot study was completed at a fractured crystalline bedrock site using a combination of soil vapor extraction (SVE) and in‐situ chemical oxidation (ISCO) with Fenton's Reagent. This system was designed to destroy 1,1,1‐trichloroethane (TCA) and its daughter products, 1,1‐dichloroethene (DCE) and 1,1‐dichloroethane (DCA). Approximately 150 pounds of volatile organic compounds (VOCs) were oxidized in‐situ or removed from the aquifer as vapor during the pilot study. Largely as a result of chemical oxidation, TCA concentrations in groundwater located within a local groundwater mound decreased by 69 to 95 percent. No significant rebound in VOC concentration was observed in these wells. Wells located outside of the groundwater mound showed less dramatic decreases in VOC concentration, and the data show that vapor stripping and short‐term groundwater migration following the oxidant injection were the key processes at these wells. Although the porosity of the aquifer at the site is on the order of 2 percent or less, the pilot study showed that SVE could be an effective remedial process in fractured crystalline rock. © 2002 Wiley Periodicals, Inc.  相似文献   

20.
A new efficient method for the chemical decomposition of polyamide 6.6 by the glycolysis and amino-glycolysis processes was proposed. The glycolysis was conducted using the mass excess of ethylene glycol (EG) as a decomposing agent in the presence of a catalyst. Also, a mixture of EG and triethylenetetramine was used as another decomposing agent in the amino-glycolysis process. The described process of decomposition did not require the use of elevated pressure. The hydroxyl and amine numbers, rheology behavior and the presence of characteristic chemical groups in the obtained glycolysates and aminoglycolysates were determined in order to characterize the reaction products. The decomposition products were defined as non-Newtonian fluids that could be described by suitable mathematical models. The conducted studies showed that the properties of the obtained intermediates depend on the mass excess of the decomposing agent used. The resulting semi-products are suitable for reusing in the synthesis of polyurethanes, which has been confirmed by the exemplary synthesis. In the reaction, 10 and 15 wt% of commercial polyol were replaced with the recovered intermediates.  相似文献   

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