996 resultados para Waste-handling unit


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This work assesses the environmental impact of a municipal solid waste incinerator with energy recovery in Forlì-Cesena province (Emilia-Romagna region, Italy). The methodology used is Life Cycle Assessment (LCA). As the plant already applies the best technologies available in waste treatment, this study focuses on the fate of the residues (bottom and fly ash) produced during combustion. Nine scenarios are made, based on different ash treatment disposing/recycling techniques. The functional unit is the amount of waste incinerated in 2011. Boundaries are set from waste arrival in the plant to the disposal/recovery of the residues produced, with energy recovery. Only the operative period is considered. Software used is GaBi 4 and the LCIA method used is CML2001. The impact categories analyzed are: abiotic depletion, acidification, eutrophication, freshwater aquatic ecotoxicity, global warming, human toxicity, ozone layer depletion, photochemical oxidant formation, terrestrial ecotoxicity and primary energy demand. Most of the data are taken from Herambiente. When primary data are not available, data from Ecoinvent and GaBi databases or literature data are used. The whole incineration process is sustainable, due to the relevant avoided impact given by co-generator. As far as regards bottom ash treatment, the most influential process is the impact savings from iron recovery. Bottom ash recycling in road construction or as building material are both valid alternatives, even if the first option faces legislative limits in Italy. Regarding fly ash inertization, the adding of cement and Ferrox treatment results the most feasible alternatives. However, this inertized fly ash can maintain its hazardous nature. The only method to ensure the stability of an inertized fly ash is to couple two different stabilization treatments. Ash stabilization technologies shall improve with the same rate of the flexibility of the national legislation about incineration residues recycling.

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Anaerobic digestion of food scraps has the potential to accomplish waste minimization, energy production, and compost or humus production. At Bucknell University, removal of food scraps from the waste stream could reduce municipal solid waste transportation costs and landfill tipping fees, and provide methane and humus for use on campus. To determine the suitability of food waste produced at Bucknell for high-solids anaerobic digestion (HSAD), a year-long characterization study was conducted. Physical and chemical properties, waste biodegradability, and annual production of biodegradable waste were assessed. Bucknell University food and landscape waste was digested at pilot-scale for over a year to test performance at low and high loading rates, ease of operation at 20% solids, benefits of codigestion of food and landscape waste, and toprovide digestate for studies to assess the curing needs of HSAD digestate. A laboratory-scale curing study was conducted to assess the curing duration required to reduce microbial activity, phytotoxicity, and odors to acceptable levels for subsequent use ofhumus. The characteristics of Bucknell University food and landscape waste were tested approximately weekly for one year, to determine chemical oxygen demand (COD), total solids (TS), volatile solids (VS), and biodegradability (from batch digestion studies). Fats, oil, and grease and total Kjeldahl nitrogen were also tested for some food waste samples. Based on the characterization and biodegradability studies, Bucknell University dining hall food waste is a good candidate for HSAD. During batch digestion studies Bucknell University food waste produced a mean of 288 mL CH4/g COD with a 95%confidence interval of 0.06 mL CH4/g COD. The addition of landscape waste for digestion increased methane production from both food and landscape waste; however, because the landscape waste biodegradability was extremely low the increase was small.Based on an informal waste audit, Bucknell could collect up to 100 tons of food waste from dining facilities each year. The pilot-scale high-solids anaerobic digestion study confirmed that digestion ofBucknell University food waste combined with landscape waste at a low organic loading rate (OLR) of 2 g COD/L reactor volume-day is feasible. During low OLR operation, stable reactor performance was demonstrated through monitoring of biogas production and composition, reactor total and volatile solids, total and soluble chemical oxygendemand, volatile fatty acid content, pH, and bicarbonate alkalinity. Low OLR HSAD of Bucknell University food waste and landscape waste combined produced 232 L CH4/kg COD and 229 L CH4/kg VS. When OLR was increased to high loading (15 g COD/L reactor volume-day) to assess maximum loading conditions, reactor performance became unstable due to ammonia accumulation and subsequent inhibition. The methaneproduction per unit COD also decreased (to 211 L CH4/kg COD fed), although methane production per unit VS increased (to 272 L CH4/kg VS fed). The degree of ammonia inhibition was investigated through respirometry in which reactor digestate was diluted and exposed to varying concentrations of ammonia. Treatments with low ammoniaconcentrations recovered quickly from ammonia inhibition within the reactor. The post-digestion curing process was studied at laboratory-scale, to provide a preliminary assessment of curing duration. Digestate was mixed with woodchips and incubated in an insulated container at 35 °C to simulate full-scale curing self-heatingconditions. Degree of digestate stabilization was determined through oxygen uptake rates, percent O2, temperature, volatile solids, and Solvita Maturity Index. Phytotoxicity was determined through observation of volatile fatty acid and ammonia concentrations.Stabilization of organics and elimination of phytotoxic compounds (after 10–15 days of curing) preceded significant reductions of volatile sulfur compounds (hydrogen sulfide, methanethiol, and dimethyl sulfide) after 15–20 days of curing. Bucknell University food waste has high biodegradability and is suitable for high-solids anaerobic digestion; however, it has a low C:N ratio which can result in ammonia accumulation under some operating conditions. The low biodegradability of Bucknell University landscape waste limits the amount of bioavailable carbon that it can contribute, making it unsuitable for use as a cosubstrate to increase the C:N ratio of food waste. Additional research is indicated to determine other cosubstrates with higher biodegradabilities that may allow successful HSAD of Bucknell University food waste at high OLRs. Some cosubstrates to investigate are office paper, field residues, or grease trap waste. A brief curing period of less than 3 weeks was sufficient to produce viable humus from digestate produced by low OLR HSAD of food and landscape waste.

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PURPOSE Hyponatremia is frequently observed in intensive care unit (ICU) patients, but there is still lack information on the physiological mechanisms of development. MATERIALS AND METHODS In this retrospective analysis we performed tonicity balances in 54 patients with ICU acquired hyponatremia. We calculated fluid and solute in and outputs during 24 hours in 106 patient days with decreasing serum-sodium levels. RESULTS We could observe a positive fluid balance as a single reason for hyponatremia in 25% of patients and a negative solute balance in 57%. In 18% both factors contributed to the decrease in serum-sodium. Hyponatremic patients had renal water retention, measured by electrolyte free water clearance calculation in 79% and positive input of free water in 67% as reasons for decline of serum-sodium. The theoretical change of serum sodium during 24 hours according to the calculations of measured balances correlated well with the real change of serum sodium (r = 0.78, P < .01). CONCLUSIONS Balance studies showed that renal water retention together with renal sodium loss and high electrolyte free water input are the major contributors to the development of hyponatremia. Control of renal water and sodium handling by urine analysis may contribute to a better fluid management in the ICU population.

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NORM (Naturally Occurring Radioactive Material) Waste Policies for the nation's oil and gas producing states have been in existence since the 1980's, when Louisiana was the first state to develop a NORM regulatory program in 1989. Since that time, expectations for NORM Waste Policies have evolved, as Health, Safety, Environment, and Social responsibility (HSE & SR) grows increasingly important to the public. Therefore, the oil and gas industry's safety and environmental performance record will face challenges in the future, about its best practices for managing the co-production of NORM wastes. ^ Within the United States, NORM is not federally regulated. The U.S. EPA claims it regulates NORM under CERCLA (superfund) and the Clean Water Act. Though, there are no universally applicable regulations for radium-based NORM waste. Therefore, individual states have taken responsibility for developing NORM regulatory programs, because of the potential radiological risk it can pose to man (bone and lung cancer) and his environment. This has led to inconsistencies in NORM Waste Policies as well as a NORM management gap in both state and federal regulatory structures. ^ Fourteen different NORM regulations and guidelines were compared between Louisiana and Texas, the nation's top two petroleum producing states. Louisiana is the country's top crude oil producer when production from its Federal offshore waters are included, and fourth in crude oil production, behind Texas, Alaska, and California when Federal offshore areas are excluded. Louisiana produces more petroleum products than any state but Texas. For these reasons, a comparative analysis between Louisiana and Texas was undertaken to identify differences in their NORM regulations and guidelines for managing, handling and disposing NORM wastes. Moreover, this analysis was undertaken because Texas is the most explored and drilled worldwide and yet appears to lag behind its neighboring state in terms of its NORM Waste Policy and developing an industry standard for handling, managing and disposing NORM. As a result of this analysis, fourteen recommendations were identified.^

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Mode of access: Internet.

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Mode of access: Internet.

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"Solid waste management series (SW-125)"

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"May 1988."

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Survival of seal pups may be affected by their ability to respond appropriately to stress. Chronic stress can adversely affect secretion of cortisol and thyroid hormones, which contribute to the control of fuel utilisation. Repeated handling could disrupt the endocrine response to stress and/or negatively impact upon mass changes during fasting. Here we investigated the effects of handling regime on cortisol and thyroid hormone levels, and body mass changes, in fasting male and female grey seal pups (Halichoerus grypus). Females had higher thyroid hormone levels than males throughout fasting and showed a reduction in cortisol midway through the fast that was not seen in males. This may reflect sex-specific fuel allocation or development. Neither handling frequency nor cumulative contact time affected plasma cortisol or thyroid hormone levels, the rate of increase in cortisol over the first five minutes of physical contact or the pattern of mass loss during fasting in either sex. The endocrine response to stress and the control of energy balance in grey seal pups appear to be robust to repeated, short periods of handling. Our results suggest that routine handling should have no additional impact on these animals than general disturbance caused by researchers moving around the colony.

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Systematic Municipal Solid Waste Management (MSWM) authorities of Sri Lanka contributes to exchange some productive outputs with localities; however it is still not in a successful mode due to limitations and environmental failures in their operation. Most of these local administrations are directly dumping Municipal Solid Waste (MSW) to an open dumping site, this manner of inappropriate disposal of MSW is become a major threat to the environment and public health in developing countries like Sri Lanka. This study was conducted for the MSWM practices of Balangoda Urban Council. The research was performed based on analyzing information obtained from field observations; reports; literature; questionnaire distribution among community; and a series of formal interviews with major stakeholders. The ongoing MSWM practices of Balangoda Urban Council encompass six categories as waste minimization and handling; waste collection; on-site separation; waste transportation; further management including grading, composting, recycling, producing sludge fertilizer; and final disposal to an open dump site. Apart from those, training sessions on MSWM are also being conducted. The purpose of this paper is to assess current status of urban waste management scenario and highlight strengths and weaknesses to understand the sustainability of the system which would help any local authority to improve MSWM.

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This study investigated the physical characteristics of lightweight concrete produced using waste materials as coarse aggregate. The study was inspired by the author’s Peace Corps service in Kilwa, Tanzania. Coconut shell, sisal fiber, and PET plastic were chosen as the test waste products due to their abundance in the area. Two mixes were produced for each waste product and the mix proportions designed for resulting compressive strengths of 3000 and 5000 psi. The proportions were selected based on guidelines for lightweight concrete from the American Concrete Institute. In preparation for mixing, coconut shells were crushed into aggregate no larger than 3/4 inch, sisal fiber was cut into pieces no longer than 3/8 inch, and PET plastic was shredded into 1/4 inch-wide strips no longer than 6 inches. Replicate samples were mixed and then cured for 28 days before they were tested for compressive strength, unit weight, and absorption. The resulting data were compared to ASTM Standards for lightweight concrete masonry units to determine their adequacy. Based on these results, there is potential for coconut shell to be used as coarse aggregate in lightweight concrete. Sisal fiber was unsuccessful in producing the appropriate compressive strength. However, the reduction in spalling of the hardened concrete and the induction of air in the mixes incorporating sisal fiber suggests that it has the potential to improve other characteristics of lightweight concrete. Concrete mixes using PET plastic as aggregate resulted in adequate compressive strengths, but were too dense to be considered ‘lightweight’ concrete. With some adjustments to slightly decrease absorption and unit weight, the PET plastic concrete mixes could be classified as medium weight concrete and, therefore, achieve many of the same benefits as would be seen with lightweight concrete.

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A report for the Iowa Waste Reduction Center and Iowa Department of Natural Resources.

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A waste sort is a process of hand-sorting onsite waste in order to quantify the amount and type of solid waste generated by businesses, organizations and municipalities to determine how much waste is ultimately ending up in the landfill. Data from waste sort events assists in identifying current waste practices and the feasibility of implementing commodity specific waste reduction, recycling and education programs.

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The central aim of this dissertation is to introduce innovative methods, models, and tools to enhance the overall performance of supply chains responsible for handling perishable products. This concept of improved performance encompasses several critical dimensions, including enhanced efficiency in supply chain operations, product quality, safety, sustainability, waste generation minimization, and compliance with norms and regulations. The research is structured around three specific research questions that provide a solid foundation for delving into and narrowing down the array of potential solutions. These questions primarily concern enhancing the overall performance of distribution networks for perishable products and optimizing the package hierarchy, extending to unconventional packaging solutions. To address these research questions effectively, a well-defined research framework guides the approach. However, the dissertation adheres to an overarching methodological approach that comprises three fundamental aspects. The first aspect centers on the necessity of systematic data sampling and categorization, including identifying critical points within food supply chains. The data collected in this context must then be organized within a customized data structure designed to feed both cyber-physical and digital twins to quantify and analyze supply chain failures with a preventive perspective.

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Pancreatic β-cells are highly sensitive to suboptimal or excess nutrients, as occurs in protein-malnutrition and obesity. Taurine (Tau) improves insulin secretion in response to nutrients and depolarizing agents. Here, we assessed the expression and function of Cav and KATP channels in islets from malnourished mice fed on a high-fat diet (HFD) and supplemented with Tau. Weaned mice received a normal (C) or a low-protein diet (R) for 6 weeks. Half of each group were fed a HFD for 8 weeks without (CH, RH) or with 5% Tau since weaning (CHT, RHT). Isolated islets from R mice showed lower insulin release with glucose and depolarizing stimuli. In CH islets, insulin secretion was increased and this was associated with enhanced KATP inhibition and Cav activity. RH islets secreted less insulin at high K(+) concentration and showed enhanced KATP activity. Tau supplementation normalized K(+)-induced secretion and enhanced glucose-induced Ca(2+) influx in RHT islets. R islets presented lower Ca(2+) influx in response to tolbutamide, and higher protein content and activity of the Kir6.2 subunit of the KATP. Tau increased the protein content of the α1.2 subunit of the Cav channels and the SNARE proteins SNAP-25 and Synt-1 in CHT islets, whereas in RHT, Kir6.2 and Synt-1 proteins were increased. In conclusion, impaired islet function in R islets is related to higher content and activity of the KATP channels. Tau treatment enhanced RHT islet secretory capacity by improving the protein expression and inhibition of the KATP channels and enhancing Synt-1 islet content.