Water consumption, case study

For any case-study built around Equation 1, we have to consider, for model input, parameters that provide emissions or environmental concentrations, intermedia transfer factors, ingestion (or other intake) rates, body weight, exposure frequency and exposure duration. For our specific case-study below, we are interested in concentrations in surface waters due to deposition from the atmosphere. The relevant intermedia transfer factor is the bioconcentration factor for fish concentration from surface water concentrations. The intake data we need are the magnitude and range of fish ingestion in our exposed population. Because PBLx is a persistent compound that accumulates in fat tissues, we will focus for this case not on exposure frequency and duration but on long-term average daily consumption. 

In this case-study, the issue of concern is the extensive exposure of human populations to PBLx, which is a persistent pollutant with multimedia and multipathway exposure potential. For PBLx, exposures occur primarily through food pathways. Here we focus on fish ingestion exposures from PBLx emissions to air that are deposited on ocean and fresh waters and accumulated in both ocean and freshwater fish. This situation focuses attention on three key pieces of information—concentration in water, biotransfer to fish and human consumption of fish. 

In order to illustrate the use of the variance propagation methods described above, we have selected for the case-study a simple three-input exposure model. The three inputs for this model include water concentration, fish BCF and fish consumption rates. The model output is dose expressed in micrograms per day averaged over a one-year exposure period. This model has the form ... 

These benefits, thought to be the result of direct influences on physiological processes of the treated plants, are referred as to physiological effects [48a], and have been most extensively studied with kresoxim-methyl and pyradostrobin. These include effects like delayed senescence, altered CO2 compensation point, reduced stomatal aperture and water consumption, and better tolerance of oxidative stress. Significantly altered levels of enzyme activities (ACC synthase, nitrate reductase, peroxidases, alternative oxidase AOX) could be observed or inferred indirectly in vivo, but in no attempted cases directly with isolated enzymes in vitro. The simplest and therefore most convindng hypothesis to explain all these many... 

This case study shows how shared resources can simultaneously improve efficiency and reduce vulnerabiUty through resource reuse. Heller et al. (1999) discuss the coucept of shared resources as a means of achieving regional eco-efficiency. In this context, information system boundaries are extended to coordinate the shared production, consumption, treatment, or reuse of electricity, water, and wastewater resources among regional utilities and manufacturing facilities. 

Ahmetovic, E. Martin, M. Grossmann, I.E. (2010) Optimization of water consumption in process industry Com—based ethanol case study. Ind. Eng. Chem. Res., 49(17), 7972-7982. 

The capabilities of the proposed approach have been illustrated with a case study. In this case ten water using operations with single contaminant are considered. The objective is to design a suitable network with the minimum capital cost and minimum freshwater consumption. Table 1 shows the limiting data for a ten processes problem. In this case there is one fixed source of freshwater and ten fixed operations. Each water user can be described by maximum and minimum allowed concentration (inlet and outlet) and the individual mass load of contaminants or the limiting flow rate. 

For the two UK case studies, the most important calibration data were the plumbosolvency of the water, the percentage of houses with lead pipes within the water system, and daily water consumptions. Pipe details, water use patterns and flow rates were less critical and general assumptions were often used (Hayes et al, 2006, 2008). For the North American case studies in Cities A, B, and C, the most important calibration data were the plumbosolvency of the water and the length and diameter distributions of the non-lead pipes used in premise plumbing. In these studies the focus of compliance assessment was either sequential 30 minutes or 6 hours stagnation - first draw sampling. For City C, the limited data available for model calibration constrained the scope of the case study. 

Vandenberghe, L.P.S., Soccol, C.R., Lebeault, J.M., et al., 1998. Intemational Congress Biotech 98 Cassava Wastes Hydrolysate an Alternative Carbon Source for Citric Acid Production by Candida Lipolytica. Portugal. Venkatesh, G., Brattebo, H., 2011. Environmental impact analysis of chemicals and energy consumption in wastewater treatment plants case study of Oslo, Norway. Water Science and Technology 63,1018-1031. 

Oil-field NORM are an environmental concern because of the potential for human exposure to ionizing radiation. The radium and radium decay products in oil-field NORM present a hazard only if taken into the body by ingestion or inhalation. The external radiation from equipment or waste containing NORM is almost never a significant concern. The discharge of radium in produced water is of concern because it may accumulate in seafood consumed by humans. Since no estabhshed safe level exists for the intake of radium, any consumption of radium in food is of potential concern. However, for the case of radium discharged in produced water, risk assessment studies show that consumption of fish caught near produced water outfalls will not pose an unacceptable human health risk, even in the worst cases. 

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