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Solid Waste (solid + waste)
Kinds of Solid Waste Terms modified by Solid Waste Selected AbstractsResidential vapor-intrusion evaluation: Long-duration passive sampling vs. short-duration active samplingREMEDIATION, Issue 4 2008Joseph E. Odencrantz Sampling indoor air for potential vapor-intrusion impacts using current standard 24-hour sample collection methods may not adequately account for temporal variability and detect contamination best represented by long-term sampling periods. Henry Schuver of the U.S. Environmental Protection Agency Office of Solid Waste stated at the September 2007 Air & Waste Management Association vapor-intrusion conference that the US EPA may consider recommending longer-term vapor sampling to achieve more accurate time-weighted-average detections. In November 2007, indoor air at four residences was sampled to measure trichloroethene (TCE) concentrations over short- and long-duration intervals. A carefully designed investigation was conducted consisting of triplicate samplers for three different investigatory methods: dedicated 6-liter Summa canisters (US EPA Method TO-15), pump/sorbent tubes (US EPA Method TO-17), and passive diffusion samplers (MDHS 80). The first two methods collected samples simultaneously for a 24-hour period, and the third method collected samples for two weeks. Data collected using Methods TO-15 (canisters) and TO-17 (tubes) provided reliable short-duration TCE concentrations that agree with prior 24-hour sampling events in each of the residences; however, the passive diffusion samplers may provide a more representative time-weighted measurement. The ratio of measured TCE concentrations between the canisters and tubes are consistent with previous results and as much as 28.0 ,g/m3 were measured. A comparison of the sampling procedures, and findings of the three methods used in this study will be presented. © 2008 Wiley Periodicals, Inc. [source] A deterministic approach to evaluate and implement monitored natural attenuation for chlorinated solventsREMEDIATION, Issue 4 2007Michael J. Truex A US EPA directive and related technical protocol outline the information needed to determine if monitored natural attenuation (MNA) for chlorinated solvents is a suitable remedy for a site. For some sites, conditions such as complex hydrology or perturbation of the contaminant plume caused by an existing remediation technology (e.g., pump-and-treat) make evaluation of MNA using only field data difficult. In these cases, a deterministic approach using reactive transport modeling can provide a technical basis to estimate how the plume will change and whether it can be expected to stabilize in the future and meet remediation goals. This type of approach was applied at the Petro-Processors Inc. Brooklawn site near Baton Rouge, Louisiana, to evaluate and implement MNA. This site consists of a multicomponent nonaqueous-phase source area creating a dissolved groundwater contamination plume in alluvial material near the Mississippi River. The hydraulic gradient of the groundwater varies seasonally with changes in the river stage. Due to the transient nature of the hydraulic gradient and the impact of a hydraulic containment system operated at the site for six years, direct field measurements could not be used to estimate natural attenuation processes. Reactive transport of contaminants were modeled using the RT3D code to estimate whether MNA has the potential to meet the site-specific remediation goals and the requirements of the US EPA Office of Solid Waste and Emergency Response Directive 9200.4-17P. Modeling results were incorporated into the long-term monitoring plan as a basis for evaluating the effectiveness of the MNA remedy. As part of the long-term monitoring plan, monitoring data will be compared to predictive simulation results to evaluate whether the plume is changing over time as predicted and can be expected to stabilize and meet remediation goals. This deterministic approach was used to support acceptance of MNA as a remedy. © 2007 Wiley Periodicals, Inc. [source] Acid Mine Drainage and Heavy Metal Pollution from Solid Waste in the Tongling Mines, ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 1 2008XU Xiaochun Abstract: Based on investigation of the characteristics of solid waste of two different mines, the Fenghuangshan copper mine and the Xinqiao pyrite mine in Tongling, Anhui province in central-east China, the possibility and the differences of acid mine drainage (AMD) of the tailings and the waste rocks are discussed, and the modes of occurrence of heavy metal elements in the mine solid waste are also studied. The Fenghuangshan copper mine hardly produces AMD, whereas the Xinqiao pyrite mine does and there are also differences in the modes of occurrence of heavy metal elements in the tailings. For the former, toxic heavy metals such as Cu, Pb, Zn, Cd, As and Hg exist mostly in the slag mode, as compared to the latter, where the deoxidization mode has a much higher content, indicating that large amounts minerals in the waste rocks have begun to oxidize at the earth surface. AMD is proved to promote the migration and spread of the heavy metals in mining waste rocks and lead to environmental pollution of the surroundings of the mine area. [source] Utilization of tannery solid waste for protease production by Synergistes sp. in solid-state fermentation and partial protease characterizationENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 1 2009Arumugam Ganesh Kumar Abstract Synergistes sp. DQ560074 produced a protease in submerged fermentation (SmF) at 400,420,U/mL and in solid-state fermentation (SSF) at 745,755,U/g. The protease, which belongs to the aspartic protease class, was active over a wide range of pH (5,7) and at high temperatures (25,45°C). The protease is stable and active in various polar protic solvents (50%,v/v) like ethanol, isopropanol, n,butanol, in polar aprotic solvents (50%,v/v) like acetonitrile, and in non-polar solvents (50%,v/v) such as ethylacetate and toluene, but not in hydrophilic organic solvents (methyl alcohol and acetone). As far as we know, this is the first contribution to the production of a mesophilic protease with solvent stability in SSF using a proteinaceous solid waste. [source] Waste Minimisation Clubs: a cost-efficient policy instrument?ENVIRONMENTAL POLICY AND GOVERNANCE, Issue 6 2001Stefan Henningsson The total amount of solid waste generated in Europe is estimated to grow by 10% every year and there is increased concern over the associated environmental impacts. As a result, the minimization of waste at source in business and industry is a top priority in the European Community's waste strategy. In the UK, regional Waste Minimisation Clubs (WMCs) have been established to promote sustainable waste management in business and industry. The company clusters taking part in these clubs have reported financial savings combined with reductions in environmental impact. These results are disseminated to encourage further savings by the UK industry. This paper examines the savings as well as the costs involved in ten WMCs. It finds that there is a lack of standardization in the reporting of WMC results. This makes it difficult to evaluate the influence of WMCs, whilst also having an adverse effect on the credibility of waste minimization in business. Despite these problems, the paper finds that there is still strong evidence to suggest that these ten WMCs have been efficient in stimulating cost savings by industry, with an average rate of return on investment of 170%. It also finds that the financial benefits for companies are key outcomes of WMCs and that these benefits significantly exceed the estimated social benefits of the reduced environmental burden. Copyright © 2001 John Wiley & Sons, Ltd and ERP Environment. [source] Prediction of municipal solid waste generation with combination of support vector machine and principal component analysis: A case study of MashhadENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 2 2009R. Noori Abstract Quantity prediction of municipal solid waste (MSW) is crucial for design and programming municipal solid waste management system (MSWMS). Because effect of various parameters on MSW quantity and its high fluctuation, prediction of generated MSW is a difficult task that can lead to enormous error. The works presented here involve developing an improved support vector machine (SVM) model, which combines the principal component analysis (PCA) technique with the SVM to forecast the weekly generated waste of Mashhad city. In this study, the PCA technique was first used to reduce and orthogonalize the original input variables (data). Then these treated data were used as new input variables in SVM model. This improved model was evaluated by using weekly time series of waste generation (WG) and the number of trucks that carry waste in week of t. These data have been collected from 2005 to 2008. By comparing the predicted WG with the observed data, the effectiveness of the proposed model was verified. Therefore, in authors' opinion, the model presented in this article is a potential tool for predicting WG and has advantages over the traditional SVM model. © 2008 American Institute of Chemical Engineers Environ Prog, 2009 [source] Trace metal distribution in soluble organic matter from municipal solid waste compost determined by size-exclusion chromatographyENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2002Arno Kaschl Abstract Municipal solid waste (MSW) composts carry high amounts of trace metals and organic complexing agents that may influence metal bioavailability and mobility after application to soils. In order to assess the degree of organic complexation of trace metals in the solution phase of MSW compost and the relevance of organic ligand type, size exclusion chromatography (SEC) was applied to compost-extracted organic ligands. Adjustment of the elution conditions minimized the interaction with the gel matrix for compost humic substances and dissolved organic matter (DOM) fractions. The SEC was then used to separate the aqueous compost extract into samples with distinct differences in chemical constituents. The highest quantities of Cu, Zn, Ni, Mn, and Cd were found to coelute with the main peak of the SEC elution curve, which, as observed by Fourier-transformed infrared (FTIR) spectroscopy, also had the highest density of carboxyl groups. The ratio of aromatic to aliphatic structures was higher for eluates with low retention times, and cations such as Al, Cr, and Fe were preferably associated with these larger organic molecules. All trace metals in the compost solution phase were bound mostly to DOM rather than forming inorganic complexes. [source] Truck schedule recovery for solid waste collection in Porto Alegre, BrazilINTERNATIONAL TRANSACTIONS IN OPERATIONAL RESEARCH, Issue 5 2008Jing-Quan Li Abstract This paper considers a truck schedule recovery problem in the context of solid waste collection in the city of Porto Alegre, Brazil. When a truck on a scheduled trip breaks down, a backup truck needs to be selected to serve the cargo on that trip and other trucks might be rescheduled in order to gain the minimum operating and delay costs. The problem consists of designing, in the case of a severe disruption in a trip, new schedules taking into account the existing trucks in the system and a set of unfinished and not initiated collection trips, on which the trucks collect the solid waste in fixed routes and empty the loads in one of the several operational recycling facilities. The main objective is to minimize the total distances traveled and delay costs, as well as to obtain balanced assignments of truck unloads into the recycling facilities, due to the social benefits of the solid waste program. We modeled the problem as a mixed-integer linear problem and used CPLEX to solve it. Finally, computational experiments are conducted on real-world data. The results show that our approach successfully reduces the distances traveled and delays, simultaneously balancing the number of trucks unloading at each recycling facility, in comparison with the current manual strategy. [source] Anaerobic biodegradation of two-phase olive mill solid wastes and liquid effluents: kinetic studies and process performanceJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 9 2006Rafael Borja Abstract The new two-phase olive oil mills produce three identifiable and separate waste streams, namely (1) the wash waters from the initial cleansing of the fruit, (2) the aqueous solid residues from the primary centrifugation and (3) the wash waters from the secondary centrifugation. As well as offering process advantages, they also consume less water. Therefore the solid residue, two-phase olive mill solid waste (OMSW), has a high organic matter concentration, giving it an elevated polluting load, and cannot be easily handled by traditional technology which deals with the conventional three-phase olive cake. In addition, the new two-phase olive mill effluents (TPOME) are made up of a mixture of effluents (1) and (3), the total volume of TPOME generated being ,0.25 dm3 kg,1 olives processed. This review aims to report the main features and characteristics of two-phase OMSW and TPOME as compared with the classical olive cake and olive mill wastewater (OMW) derived from the three-phase manufacturing process. The advantages and disadvantages of the two-phase decanting process are summarised. The anaerobic digestibility of two-phase OMSW using different influent substrate concentrations is reported. Kinetic studies of anaerobic digestion of two-phase OMSW are also reviewed and summarised, as well as mass balances to predict the behaviour of the reactor and simplified kinetic models for studying the hydrolysis, acidogenic and methanogenic steps of one- and two-stage anaerobic digestion of OMSW. The review also includes the following: assays of anaerobic digestion of wastewaters from the washing of olives, of olive oil and the two together using fluidised beds and hybrid reactors; the kinetics, performance, stability, purification efficiencies and methane yield coefficients. Copyright © 2006 Society of Chemical Industry [source] Volatile fatty acid production during anaerobic mesophilic digestion of solid potato wasteJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 7 2004Wilson Parawira Abstract The production of volatile fatty acids by anaerobic digestion of solid potato waste was investigated using a batch solid waste reactor with a working capacity of 2 dm,3 at 37°C. Solid potato waste was packed into the digester and the organic content of the waste was released by microbial activity by circulating water over the bed, using batch loads of 500 g or 1000 g potato waste. The sequence of appearance of the volatile fatty acids was (acetic, propionic); (n -butyric); (n -valeric, iso-valeric, caproic); (iso-butyric). After 300 h digestion of potato waste on a small scale, the fermentation products were chiefly (mg g,1 total VFAs): acetic acid (420), butyric acid (310), propionic acid (140) and caproic acid (90), with insignificant amounts of iso-butyric acid, n -valeric and iso-valeric acids. When the load of potato solids was increased, the volatile fatty acid content was similar, but butyric acid constituted 110 mg g,1 and lactic acid 400 mg g,1 of the total volatile fatty acids. The maximum soluble chemical oxygen demand (COD) achieved under the experimental conditions used was 27 and 37 g COD dm,3 at low and high loadings of potato solids, respectively. The total volatile fatty acids reached 19 g dm,3 of leachate at both loads of potato solid waste. Gas production was negligible, indicating that methanogenic activity was effectively inhibited. Copyright © 2004 Society of Chemical Industry [source] Pyrolysis of tetra pack in municipal solid wasteJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 8 2001Chao-Hsiung Wu Abstract The pyrolysis of tetra pack in nitrogen was investigated with a thermogravimetric analysis (TGA) reaction system. The pyrolysis kinetics experiments for the tetra pack and its main components (kraft paper and low-density poly(ethene) (LDPE)) were carried out at heating rates (,) of 5.2, 12.8, 21.8,K,min,1. The results indicated that the one-reaction model and two-reaction model could be used to describe the pyrolysis of LDPE and kraft paper respectively. The total reaction rate of tetra pack can be expressed by the summation of the individual class of LDPE and kraft paper by multiplying the weighting factors. The pyrolysis products experiments were carried out at a constant heating rate of 5.2,K,min,1. The gaseous products were collected at room temperature (298,K) and analyzed by gas chromatography (GC). The residues were collected at some significant pyrolysis reaction temperatures and analyzed by an elemental analyzer (EA) and X-ray powdered diffraction (XRPD). The accumulated masses and the instantaneous concentrations of gaseous products were obtained under the experimental conditions. The major gaseous products included non-hydrocarbons (CO2, CO, and H2O) and hydrocarbons (C1,5). In the XRPD analysis, the results indicated that pure aluminum foil could be obtained from the final residues. The proposed model may be supported by the pyrolysis mechanisms with product distribution. © 2001 Society of Chemical Industry [source] PROTEINASES IN HYBRID CATFISH VISCERA: CHARACTERIZATION AND EFFECT OF EXTRACTION MEDIAJOURNAL OF FOOD BIOCHEMISTRY, Issue 4 2010SAPPASITH KLOMKLAO ABSTRACT Proteolytic activity from viscera extract of hybrid catfish (Clarias macrocephalus × Clarias gariepinus) was investigated. Optimal pH and temperature for casein hydrolysis were 9.0 and 50C, respectively. The enzyme was stable to heat treatment up to 40C and over a pH range of 7,11 for 30,120 min. The proteolytic activity was effectively inhibited by soybean trypsin inhibitor, benzamidine, phenylmethylsulfonyl fluoride and N -p-tosyl-L-lysine chloromethyl ketone. Activities of the viscera extract continuously decreased as NaCl concentration increased, while activities increased as CaCl2 concentration increased. Based on the proteinase activity of zones separated by electrophoresis, the molecular mass of the major proteinases in hybrid catfish viscera was 23 and 20 kDa. The effect of extraction media on recovery of proteinases was also studied. Extraction of the viscera powder with 50 mM Tris-HCl, pH 7.0 containing 0.5 M NaCl and 0.2% (v/v) Brij 35 rendered a higher recovery of proteinase activity than other extractants tested (P < 0.05). The results suggested that major proteinases in hybrid catfish viscera were heat-activated alkaline proteinases, most likely trypsin-like serine proteinases. PRACTICAL APPLICATIONS Hybrid catfish viscera is an abundant and underutilized resource that can be used as a unique proteinase source. Proteinase from various sources catalyzes the hydrolysis of peptide bonds. Thus, it is expected that like other proteinases, hybrid catfish proteinase would be useful in biomedical, food and beverage application. Moreover, the presented extraction media could be adopted to recover the trypsin-like serine proteinase from hybrid catfish viscera, which is currently a solid waste of Pa-duk-ra industry. [source] EFFECT OF POLYGODIAL ON MECHANICAL, OPTICAL AND BARRIER PROPERTIES OF CHITOSAN FILMSJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 2 2010L. MORENO-OSORIO ABSTRACT The mechanical, optical and barrier properties of chitosan films containing polygodial (0.0, 2.7, 13.9, 25.0 mg/g of chitosan) were studied. Water vapor permeability (WVP), tensile strength, percentage elongation at break, CIELab color parameters, hue angle and chroma of films were determined. Fourier transform infrared (FTIR) was also performed to determine functional group interaction between the matrix and polygodial added. The use of polygodial resulted in stronger films without losing their extensibility and with low WVP. Films became darker with yellow-green coloration with increasing polygodial concentration. Polygodial added to chitosan films did not have any interaction with the amino groups of chitosan as measured by FTIR. Polygodial as a natural dialdehyde can effectively be applied to enhance some physical properties of edible films prepared with chitosan. PRACTICAL APPLICATIONS There has been an increased interest in the study of edible,biodegradable packaging films during the last decade, offering an alternative and partial solution to the problem of accumulation of solid waste composed of synthetic inert polymers, and chitosan films has been studied with this purpose. Furthermore, replacing synthetic additives by natural compounds such us polygodial can be a suitable manner to improve some physical properties of those chitosan films. [source] APPLICATION OF EXPERIMENTAL DESIGN METHOD TO THE OIL EXTRACTION FROM OLIVE CAKEJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 2 2009SMAIL MEZIANE ABSTRACT Olive cake is an important solid waste of the olive oil production. It still contains a certain quantity of oil that can be recovered by means of solvent extraction. In this study, two-level full factorial design was performed to evaluate the effects of four variables and their interactions on the oil extraction by the ethanol 96.0% in a batch reactor. The variables included size of particles, temperature, and time of contact and solvent-to-solids ratio. The statistical analysis of the experimental data showed that the extracted oil mass depends on all the examined variables. It also depends on the interactions between size of particles and solvent-to-solid ratio and size of particles and temperature. The experimental data were in good agreement with those predicted by the model. PRACTICAL APPLICATIONS Olive cake is solid waste of the olive oil industry that is available in large amounts in many Mediterranean countries and at very low cost. It can be treated or valorized, enabling at the same time the solution to environmental problems caused by the olive oil production process. The economic interest that it presents is especially because of the residual oil that it contains and that can be recovered by solvent extraction. However, this solid,liquid extraction depends on several parameters: the ones inherent to the products (structure and properties of the sample, nature of extraction solvent); and the others to the extraction process (time of contact, temperature of extraction, solvent-to-solid ratio, stirring velocity). The experimental design method enables to determine the most important variables and their interaction in the extraction process at the same time performing a low number of experiments. [source] Materials Metabolism Analysis of China's Highway Traffic System (HTS) for Promoting Circular EconomyJOURNAL OF INDUSTRIAL ECOLOGY, Issue 4 2010Zongguo Wen Summary With the rapid growth of highway mileage and vehicles, the Chinese highway traffic system (HTS) has become one of the great resource consumers. This article attempts to evaluate the material metabolism of China's HTS during 2001,2005 using the approach of material flow analysis (MFA) and to explore possible measures to promote circular economy throughout HTS. We measured a set of indicators to illustrate the whole material metabolism of China's HTS. The results indicated that the direct material input (DMI) of China's HTS increased from 1181.26 million tonnes (Mt) in 2001 to 1,874.57 Mt in 2005, and about 80% of DMI was accumulated in the system as infrastructure and vehicles. The domestic processed output (DPO) increased by 59.0% from 2001 to 2005. Carbon dioxide and solid waste accounted for 80.5% and 10.4% of DPO, respectively. The increase of resource consumption and pollutant emissions kept pace with the growth of transportation turnover. All these suggest that China's HTS still followed an extensive linear developing pattern with large resource consumption and heavy pollution emissions during the study period, which brought great challenges to the resources and the environment. Therefore, it's high time for China to implement a circular economy throughout the HTS by instituting resource and energy savings, by reducing emissions in the field of infrastructure construction and maintenance, by reducing vehicles' energy and materials consumption, and by recycling waste materials. [source] From Cradle to Grave: Extended Producer Responsibility for Household Hazardous Wastes in British ColumbiaJOURNAL OF INDUSTRIAL ECOLOGY, Issue 2 2001Ronald J. Driedger Summary Household hazardous wastes (HHWs), the discarded pesticides, solvents, paints, lubricating oil, and similar products common to residences throughout the industrial world, create problems for governments charged with managing solid waste. When disposed of improperly in landfills or incinerators or if dumped illegally, HHW may contribute to soil and water contamination. A most common management tool for HHW is a special collection effort that segregates HHW from normal trash and disposes of it in an approved manner, all at a higher cost to the governmental jurisdiction. The Canadian province of British Columbia (BC) has undertaken a different approach, based on the use of extended producer responsibility (EPR). BC's efforts began in 1992 with adoption of a regulation on used lubricating oil (lube oil). More than 40 million liters (L) of used lube oil have been collected annually through the EPR system established under this regulation. A regulation establishing producer responsibility for postconsumer paints followed in 1994. BC enacted an additional regulation establishing EPR in 1997 for solvents/flammable liquids, domestic pesticides, gasoline, and pharmaceuticals. As a result of the application of EPR to HHW, local government costs for managing HHW and the amount of HHW identified in municipal waste have declined. Although the regulations appear to have mixed success in prompting consumers to avoid products that result in HHW, there are indications that they may be more effective than conventional management efforts. Based on BC's experience with EPR, key factors for successful implementation include maintaining flexibility in program design, creating viable funding alternatives, aggressive enforcement to provide a level playing field, and adopting policies that maximize diversion of HHW from landfills, while minimizing waste generation, setting targets for reuse and recycling, promoting consumer awareness and convenience, involving local government jurisdictions, and monitoring outcomes. [source] Speciation of zinc in secondary fly ashes of municipal solid waste at high temperaturesJOURNAL OF SYNCHROTRON RADIATION, Issue 4 2009Meijuan Yu The evaporation aerosols produced during the vitrification process of municipal solid waste incinerators (MSWI) fly ash represent a potential environmental risk owing to their high content of heavy metals. In this research, high-temperature heating processes were carried out on fly ashes collected from bag houses in a Chinese MSWI plant and the secondary fly ashes (SFA) were separately collected at three high temperatures (1273,K, 1423,K and 1523,K) below the melting range. Elemental analysis showed that high contents of both zinc and chlorine were present in these SFA samples and, according to the standard of the heavy metals industrial grade of ore, SFAs can be re-used as metallurgical raw materials or rich ore. Moreover, as shown by XAS analysis and for different high temperatures, zinc environments in the three SFA samples were characterized by the same local structure of the zinc chloride. As a consequence, a zinc recycling procedure can be easily designed based on the configuration information. [source] Isolation of clinically relevant fungal species from solid waste and environment of dental health servicesLETTERS IN APPLIED MICROBIOLOGY, Issue 4 2010C.D. Vieira Abstract Aims:, This study was undertaken to detect, identify and determine antifungal susceptibility of yeast strains isolated from dental solid waste and to evaluate airborne fungi in the Brazilian dental health care environment and in the waste storage room. Methods and Results:, A group of 17 yeast strains were identified by macroscopic and microscopic characteristics, API 20C Aux system and Multiplex PCR. All 104 airborne fungal colonies were identified by macroscopic and microscopic morphology. The CLSI broth microdilution method was utilized as the susceptibility test. Candida parapsilosis was the prevailing yeast species recovered from waste, followed by Rhodotorula glutinis. Three strains of Candida guilliermondii presented minimal inhibitory concentration values considered to be susceptible dose dependent (2 ,g ml,1) to voriconazole. Of all airborne fungal species, 69% were recovered from the waste storage room and 31% were recovered from the clinical/surgical environment. Most of them were identified as Cladosporium spp. Conclusions:, These findings reinforce the potential risk of waste handling and point out the need for safe management to minimize the spread of these agents to the environment. Filamentous fungi isolation in almost all sampled environments indicates that a periodic monitoring of airborne microbiota in the dental health care service environment is required. Significance and Impact of the Study:, The survival of yeast strains for 48 h suggests that dental waste should be carefully controlled and monitored. [source] Life cycle inventory and analysis of re-usable plastic containers and display-ready corrugated containers used for packaging fresh fruits and vegetablesPACKAGING TECHNOLOGY AND SCIENCE, Issue 5 2006S. Paul Singh Abstract Today's demanding distribution challenges require engineers to choose from various types of materials, design and construction methods, to develop containers that can deliver goods with minimal damage. The challenge is even greater when packing and shipping goods which are perishable and sensitive to both physical and climatic changes in environment. In recent years the type of packaging material used to design and construct containers has undergone more scrutiny than ever, due to environmental challenges. This study focuses on two types of containers that have been designed and are being used to pack and ship fresh fruits and vegetables. The study compares the re-usable plastic containers to single-use display-ready paper corrugated trays. Results show that, based on the scope of this study and comparing 10 different produce items, such as apples, carrots, grapes, oranges, onions, tomatoes, strawberries, etc., the re-usable plastic containers require 39% less total energy, produce 95% less total solid waste and generate 29% less total greenhouse gas emissions. This study focused on the North American market. Major European nations have been using a large number of re-usable plastic containers for these types of fresh produce for the past three decades. This study was initiated by the Franklin Associates, an independent consulting firm for allowing an in-depth review of all data and results from a two year study titled: Life Cycle Inventory of Reusable Plastic Containers and Display-Ready Corrugated Containers Used for Fresh Produce Applications. Copyright © 2006 John Wiley & Sons, Ltd. [source] Life cycle environmental performance and improvement of a yogurt product delivery systemPACKAGING TECHNOLOGY AND SCIENCE, Issue 2 2004Gregory A. Keoleian Abstract A life cycle assessment was conducted to evaluate the environmental performance of the yogurt product delivery system used by Stonyfield Farm. A life cycle model was developed which included material production, manufacturing and disposition for primary and secondary packaging, as well as the related transportation links between these stages and filling, retail and the point of consumption. Product delivery systems (PDS) that utilized 4, 6, 8 and 32,oz polypropylene (PP) cups and 2,oz linear low-density polyethylene (LLDPE) tubes were analysed. Ten strategies for improving the environmental performance of these systems were proposed and their impacts on the total life cycle burden were analysed. The life cycle energy consumption for the 2, 4, 6, 8 and 32,oz containers was 4050, 4670, 5230, 4390 and 3620,MJ/1000,lb yogurt delivered to market, respectively. Material production of the primary packaging accounted for 58% of the life cycle energy, while Distribution 3 (yogurt delivery to distributors/retailers) alone accounted for one-third of the life cycle total energy. The life cycle solid waste profile showed that as the container size decreased, the solid waste burden increased, from 27.3,kg (32,oz) to 42.8,kg (6,oz) per 1000,lb yogurt delivered to market. This relationship was even more pronounced for the 4,oz (47.5,kg) and 2,oz (56.2,kg) product delivery systems. The greatest potential improvements in the environmental performance of the PDS are achievable through redesigning the primary packaging and using alternative manufacturing techniques for the yogurt cups. Shifting from injection moulding to thermoforming of 32,oz container reduces the life cycle energy and solid waste by 18.6% and 19.5%, respectively, primarily due to light-weighting. Elimination of lids for 6,oz and 8,oz containers provided similar benefits. Consumers purchasing yogurt in 32,oz instead of 6,oz containers can save 14.5% of the life cycle energy and decrease solid waste by 27.2%. Copyright © 2004 John Wiley & Sons, Ltd. [source] A composite model for municipal solid wastePROCEEDINGS IN APPLIED MATHEMATICS & MECHANICS, Issue 1 2005Volker Krase The mechanical behaviour of municipal solid waste is very complex due to the internal structure and differs considerably from ordinary materials. The fundamental idea of the presented mechanical constitutive model is the split of the material into two solid phases, justified by experimental observations, where fibrous particles signi.cantly influence the composite behaviour. Constitutive laws are independently introduced for each phase. A .nite deformation theory is applied, whereas the concept of elastoplasticity allows reproducing the highly non-linear stress-strain relations. A creep law describes time-depending deformation under compression loads. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Changes in the Usage of Enterprise Funds by Large City GovernmentsPUBLIC BUDGETING AND FINANCE, Issue 2 2000Beverly S. Bunch Using a nationwide sample of large cities, this article analyzes changes in the use of enterprise funds during the past decade. The major findings are that (1) the aggregate number of enterprise funds increased, with the largest increases occurring in solid waste and drainage; (2) part of the increase was offset by the elimination of some enterprise funds, particularly in the area of recreational services; (3) 60 percent of the cities experienced one or more changes in the types of enterprise funds they used; (4) the revenues associated with most types of enterprise funds have increased at a faster rate than general fund revenues; and (5) some cities are using alternative fiscal structures (e.g., special revenue funds and discrete component units) to account for services that are reported as enterprise funds in other cities. A continuum of fiscal structures is presented as a framework for addressing why cities might choose one structure over another and what the possible implications of a particular fiscal structure might be. [source] Effect of settled sludge on dissolved ammonia concentration in tanks used to grow abalone (Haliotis midae L.) fed a formulated dietAQUACULTURE RESEARCH, Issue 2 2009Rowan D Yearsley Abstract The relative contribution that solid waste or ,sludge', which accumulates at the bottom of abalone (Haliotis midae L.) tanks, makes to dissolved ammonia has not been established. Sludge was allowed to accumulate in 10 fully stocked abalone tanks, fed a formulated feed (Abfeed®; Marifeed, South Africa), for 24 days. Sludge was subsequently siphoned from five of these tanks. Total ammonia nitrogen (TAN) production and toxic, free ammonia nitrogen (FAN) were recorded in the tanks from which sludge was removed and compared with those from which sludge was not removed over the subsequent 50 h. Tanks with neither abalone nor sludge present were used as a control. The mean production of TAN (±standard deviation) was an average of 44% higher in tanks from which sludge was not removed compared with those from which it was, indicating that the sludge was a significant contributor to dissolved ammonia in the tanks. The toxic FAN concentrations were correspondingly higher in tanks with sludge present (2.3±0.3 ,L,1) compared with cleaned tanks (1.9±0.1 ,L,1). Our results indicate that regular removal of sludge from abalone tanks should significantly reduce the dissolved ammonia levels, thereby improving water quality in the culture environment. [source] Operation of a municipal solid waste co-combustion pilot plantASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 6 2007V. K. C. Lee Abstract The co-combustion of municipal solid waste (MSW) is a novel and highly integrated design combining cement manufacturing, thermal processing of MSW and energy/electricity production (termed the Co-Co process). This novel design of the Co-Co process was developed in 2003,2004 and a pilot plant with a capacity of 40 tonnes per day was constructed and commissioned in 2005. The pilot plant was operated for a period of 10 weeks during 2005. Various feed protocols, namely, MSW as received and after removal of recyclables, were tested. Stack emissions were monitored either continuously (gas emission) or periodically (dioxins and heavy metal emissions). Solid residues including bottom ash and fly ash were also sampled and analysed for heavy metals and dioxins periodically. It was found that the levels of dioxins in the stack emissions and fly ash were below normal MSW thermal treatment processes, and government environmental and international limits (more than 1000 times less). Other gases, such CO, NOx, SOx and HCl, were also well below government environmental licence limits as defined by a best practical means (BPM). In addition, the materials recovery and recycling facility (MRRF) was tested. It demonstrated that different fractions, including metals, plastics and glass, of the MSW could be separated and recovered. The Co-Co process was successfully demonstrated and its emission levels were well below normal MSW thermal treatment processes. Copyright © 2007 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Effect of inhibition treatment, type of inocula, and incubation temperature on batch H2 production from organic solid wasteBIOTECHNOLOGY & BIOENGINEERING, Issue 3 2006Idania Valdez-Vazquez Abstract Two types of induction treatments (heat-shock pretreatment, HSP, and acetylene, Ac), inocula (meso and thermophilic) and incubation temperatures (37 and 55°C) were tested according to a full factorial design 23 with the aim of assessing their effects on cumulative H2 production (PH, mmol H2/mini-reactor), initial H2 production rate (Ri,H, µmol H2/(g VSi,×,h)), lag time (Tlag, h), and metabolites distribution when fermenting organic solid waste with an undefined anerobic consortia in batch mini-reactors. Type of inocula did not have a significant effect on PH, Tlag, and Ri,H except for organic acids production: mini-reactors seeded with thermophilic inocula had the highest organic acid production. Concerning the induction treatment, it was found that on the average Ac only affected in a positive way the PH and Tlag. Thus, PH in Ac-inhibited units (6.97) was 20% larger than those in HSP-inhibited units (5.77). Also, Ac favored a shorter Tlag for PH in comparison with HSP (180 vs. 366). Additionally, a positive correlation was found between H2 and organic acid production. In contrast, solvent concentration in heat-shocked mini-reactors were slightly higher than in reactors spiked with Ac. Regarding the incubation temperature, on the average mesophilic temperature affected in a positive and very significant way PH (10.07 vs. 2.67) and Ri,H (2.43 vs. 0.76) with minimum Tlag (87 vs. 459). The positive correlation between H2 and organic acids production was found again. Yet, incubation temperature did not seem to affect solvent production. A strong interaction was observed between induction treatment and incubation temperature. Thus, Ac-inhibited units showed higher values of PH and Ri,H than that HSP-inhibited units only under thermophilic incubation. Contrary to this, HSP-inhibited units showed the highest values of PH and Ri,H only under mesophilic conditions. Therefore, the superiority of an induction treatment seems to strongly depend on the incubation temperature. © 2006 Wiley Periodicals, Inc. [source] Acid Mine Drainage and Heavy Metal Pollution from Solid Waste in the Tongling Mines, ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 1 2008XU Xiaochun Abstract: Based on investigation of the characteristics of solid waste of two different mines, the Fenghuangshan copper mine and the Xinqiao pyrite mine in Tongling, Anhui province in central-east China, the possibility and the differences of acid mine drainage (AMD) of the tailings and the waste rocks are discussed, and the modes of occurrence of heavy metal elements in the mine solid waste are also studied. The Fenghuangshan copper mine hardly produces AMD, whereas the Xinqiao pyrite mine does and there are also differences in the modes of occurrence of heavy metal elements in the tailings. For the former, toxic heavy metals such as Cu, Pb, Zn, Cd, As and Hg exist mostly in the slag mode, as compared to the latter, where the deoxidization mode has a much higher content, indicating that large amounts minerals in the waste rocks have begun to oxidize at the earth surface. AMD is proved to promote the migration and spread of the heavy metals in mining waste rocks and lead to environmental pollution of the surroundings of the mine area. [source] Which Controls the Depolymerization of Cellulose in Ionic Liquids: The Solid Acid Catalyst or Cellulose?CHEMSUSCHEM CHEMISTRY AND SUSTAINABILITY, ENERGY & MATERIALS, Issue 2 2010Roberto Rinaldi Dr. Abstract Cellulose is a renewable and widely available feedstock. It is a biopolymer that is typically found in wood, straw, grass, municipal solid waste, and crop residues. Its use as raw material for biofuel production opens up the possibility of sustainable biorefinery schemes that do not compete with food supply. Tapping into this feedstock for the production of biofuels and chemicals requires,as the first-step,its depolymerization or its hydrolysis into intermediates that are more susceptible to chemical and/or biological transformations. We have shown earlier that solid acids selectively catalyze the depolymerization of cellulose solubilized in 1-butyl-3-methylimidazolium chloride (BMIMCl) at 100,°C. Here, we address the factors responsible for the control of this reaction. Both cellulose and solid acid catalysts have distinct and important roles in the process. Describing the depolymerization of cellulose by the equivalent number of scissions occurring in the cellulosic chains allows a direct correlation between the product yields and the extent of the polymer breakdown. The effect of the acid strength on the depolymerization of cellulose is discussed in detail. Practical aspects of the reaction, concerning the homogeneous nature of the catalysis in spite of the use of a solid acid catalyst, are thoroughly addressed. The effect of impurities present in the imidazolium-based ionic liquids on the reaction performance, the suitability of different ionic liquids as solvents, and the recyclability of Amberlyst 15DRY and BMIMCl are also presented. [source] Agricultural soils spiked with copper mine wastes and copper concentrate: Implications for copper bioavailability and bioaccumulation,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2006Rosanna Ginocchio Abstract A better understanding of exposure to and effects of copper-rich pollutants in soils is required for accurate environmental risk assessment of copper. A greenhouse experiment was conducted to study copper bioavailability and bioaccumulation in agricultural soils spiked with different types of copper-rich mine solid wastes (copper ore, tailing sand, smelter dust, and smelter slag) and copper concentrate. A copper salt (copper sulfate, CuSO4) that frequently is used to assess soil copper bioavailability and phytotoxicity also was included for comparison. Results showed that smelter dust, tailing sand, and CuSO4 are more likely to be bioavailable and, thus, toxic to plants compared with smelter slag, concentrate, and ore at equivalent total copper concentrations. Differences may be explained by intrinsic differences in copper solubilization from the source materials, but also by their capability to decrease soil pH (confounding effect). The copper toxicity and bioaccumulation in plants also varied according to soil physicochemical characteristics (e.g., pH and total organic carbon) and the available levels of plant nutrients, such as nitrogen, phosphorus, and potassium. Chemistry/mineralogy of mine materials, soil/pore-water chemistry, and plant physiological status thus should be integrated for building adequate models to predict phytotoxicity and environmental risk of copper. [source] Anaerobic biodegradation of two-phase olive mill solid wastes and liquid effluents: kinetic studies and process performanceJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 9 2006Rafael Borja Abstract The new two-phase olive oil mills produce three identifiable and separate waste streams, namely (1) the wash waters from the initial cleansing of the fruit, (2) the aqueous solid residues from the primary centrifugation and (3) the wash waters from the secondary centrifugation. As well as offering process advantages, they also consume less water. Therefore the solid residue, two-phase olive mill solid waste (OMSW), has a high organic matter concentration, giving it an elevated polluting load, and cannot be easily handled by traditional technology which deals with the conventional three-phase olive cake. In addition, the new two-phase olive mill effluents (TPOME) are made up of a mixture of effluents (1) and (3), the total volume of TPOME generated being ,0.25 dm3 kg,1 olives processed. This review aims to report the main features and characteristics of two-phase OMSW and TPOME as compared with the classical olive cake and olive mill wastewater (OMW) derived from the three-phase manufacturing process. The advantages and disadvantages of the two-phase decanting process are summarised. The anaerobic digestibility of two-phase OMSW using different influent substrate concentrations is reported. Kinetic studies of anaerobic digestion of two-phase OMSW are also reviewed and summarised, as well as mass balances to predict the behaviour of the reactor and simplified kinetic models for studying the hydrolysis, acidogenic and methanogenic steps of one- and two-stage anaerobic digestion of OMSW. The review also includes the following: assays of anaerobic digestion of wastewaters from the washing of olives, of olive oil and the two together using fluidised beds and hybrid reactors; the kinetics, performance, stability, purification efficiencies and methane yield coefficients. Copyright © 2006 Society of Chemical Industry [source] Effect of inoculation dosing on the composting of source-selected organic fraction of municipal solid wastesJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 3 2006Raquel Barrena Abstract The effects of a commercial inoculum (MicroGest 10X, Brookside Agra L.C.) on the field-scale composting of the source-selected organic fraction of municipal solid wastes (OFMSW) have been studied by following routine parameters of the composting process (temperature, oxygen content and moisture) and biologically-related tests such as the respirometric index and the maturity grade. The inoculum was added to composting piles of OFMSW at different levels: control (no added inoculum), treatment A (105 CFU g,1 of OFMSW), treatment B (106 CFU g,1 of OFMSW) and treatment C (107 CFU g,1 of OFMSW). The inoculum selected produced a significant acceleration of the composting process with high levels of biological activity in the thermophilic phase. In terms of the acceleration of composting and economy the optimal treatment was B, which produced a reduction of approximately half of the total composting time. Treatment C did not improve significantly the results obtained with treatment B, whereas treatment A has little effect on the composting of OFMSW when compared with the control experiment. Respirometric index (determined at 55 °C) and maturity grade appeared to be the most reliable tests to follow the biological activity of the composting of OFMSW. On the other hand, routine parameters such as temperature, oxygen content and moisture showed no significant differences among the different inoculation levels tested in the composting process. Copyright © 2005 Society of Chemical Industry [source] | |||||||||||||||||||||||||||||||||||||