A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

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Boundary flux modelling for purification optimization of differently-pretreated agro-industrial wastewater with nanofiltration

The design and operation of membrane purification plants implies the prediction and control of dynamic fouling phenomena as a key to succeed. In this research article, the boundary flux theory was used to set-up and control the operating framework and model the performance of a NF membrane operation, for the purification of olive mill wastewater (OMW) previously conducted to different pretreatments. Olive oil is produced by means of a technological process which avoids the use any chemicals. In this line, this industry is concerned to make the whole process environmentally friendly, and this comprises the treatment of the wastewater generated. The operation of the NF membrane unit upon the boundary flux conditions ensured high steady-state permeate productivity (50.1–68.2 L h -1 m -2 ) while at the same time could minimize the fouling build-up on the membrane for every feedstock (0.02–0.08 L h -2 m -2 bar -1 ). This can help make the process economically sustainable, providing high feed recovery and significant organic pollutants rejection efficiencies. The latter would permit the compliance of the standard limits to reutilize all treated effluent streams for irrigation purposes, and even the target requirements for discharge in municipal sewers systems, rendering the process more environmentally sustainable

Batch Membrane Treatment of Olive Vegetation Wastewater from Two-Phase and Three-Phase Olive Oil Production Processes by Threshold Flux Based Methods

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Threshold performance of a spiral-wound reverse osmosis membrane in the treatment of olive mill effluents from two-phase and three-phase extraction processes

A reverse osmosis (RO) treatment stage was examined for the complete depuration of the different effluents exiting the olive mill factories (OMW) working with diverse extraction procedures, that is, the two-phase and the three-phase extraction processes, respectively. In the present work, the modelization of batch RO purification of OMW by means of the relevant equations of the threshold flux theory for fouling control and plant dimension is addressed. Results show that higher threshold flux values (20.2-22.1% increase) and major feed recovery rates (80.2-85.0%) as well as very significant reduction of the long-term fouling index (27.3-52.7%) were achieved by using as pretreatment steps the following series of processes: pH-T flocculation, UV/TiO2 photocatalysis, UF and NF in series. This leads to both lower energy and capital costs, in particular a reduction of the required membrane area in case of batch membrane processes equal to 22.3-44.8%. Accurate prediction of the rejection behavior was attained by the used leaky solution-diffusion model in all cases, with reflection coefficients (σCOD) ranging from 0.86 to 1.0. The purified effluent streams are finally compatible with irrigation water quality standards (COD values below 1000mgL-1). © 2014 Elsevier B.V

Batch membrane treatment of olive vegetation wastewater from two-phase olive oil production process by threshold flux based methods

The more efficient continuous centrifugation-based olive oil extraction processes brought as drawback a significant increment of the generated effluents, highlighting olive vegetation wastewater (OVW) as the most polluted. In this work, OVW from a two-phase olive oil extraction process (OVW-2) was treated by means of batch membrane operations in sequence comprising UF, NF and RO. This treatment is capable of successfully removing the organic matter and other pollutants from the wastewater, but membrane fouling can limit drastically membranes operation and longevity. Threshold flux-based methods represent a reliable tool to avoid fouling problems and were formerly applied to treat OVW streams coming from a three-phase production line (OVW-3). Below threshold flux conditions, no relevant rates of fouling are observed, thus making the treatment process technically and economically feasible. In order to increase the threshold flux values, some pretreatment processes were conducted on the feedstock, such as pH-T flocculation and successively photocatalysis by novel lab-made titanium dioxide nanoparticles. The latter provided 22.3%, 17.6% and 20.4% further threshold flux increase to UF, NF and RO, respectively. At the end, a permeate with COD equal to 121 mg/L was successfully obtained, respecting both Italian and Spanish standards for discharging purified OVW-2 in municipal sewers. (c) 2012 Elsevier B.V. All rights reserved

Natural caprine whey oligosaccharides separated by membrane technology and profile evaluation by capillary electrophoresis

The functional food market is growing rapidly and membrane processing offers several advantages over conventional methods for separation, fractionation and recovery of bioactive components. The aim of the present study was to select a process that could be implemented easily on an industrial scale for the isolation of natural lactose-derived oligosaccharides (OS) from caprine whey, enabling the development of functional foods for clinical and infant nutrition. The most efficient process was the combination of a pre-treatment to eliminate proteins and fat, using an ultrafiltration (UF) membrane of 25 kDa molecular weight cut off (MWCO), followed by a tighter UF membrane with 1 kDa MWCO. Circa 90% of the carbohydrates recovered in the final retentate were OS. Capillary electrophoresis was used to evaluate the OS profile in this retentate. The combined membrane-processing system is thus a promising technique for obtaining natural concentrated OS from whey. Powere

In vitro digestion assays using dynamic models for essential minerals in brazilian goat cheeses

Goat cheeses have important nutritional properties, with an emphasis on proteins, lipids (high digestibility), and essential minerals. This study analyzes the bioavailability of Ca, Mg, and Zn in Brazilian cheeses using an in vitro dynamic digestion method. Two self-produced fresh cheeses, cow and goat Minas frescal cheese, and two commercial matured goat cheeses, Blue and Pyramid, were analyzed. Brazilian goat cheeses are potential sources of essential minerals (Ca, Mg, and Zn). Variations of 103–598 mg/100 g for Ca, 13.62–41.64 mg/100 g for Mg, and 9.79–13.23 mg/100 g for Zn were observed in the studied samples. The pH concentration, enzyme performance, and protein and lipid content of Brazilian cheeses affected the solubility of essential minerals in the intestinal fraction. The percentages of minerals found in the permeate stream, equivalent to absorption of Ca and Zn, were lower in Minas frescal goat cheese than Minas frescal cow cheese, whereas that of Mg was higher. Pyramid and Minas frescal goat cheeses had the higher values of Mg and Zn bioavailability, respectively. This study supports, for the first time, the usefulness of the dynamic simulation of the human gastrointestinal tract for the study of mineral bioavailability in cheeses.The authors would like to thank the São Paulo Research Foundation (FAPESP) for the scholarship grant of PhD student José Teixeira, and for the research internship abroad (regular scholarship n° 2018/08864–8 and BEPE—n° 2019/13600–2). Juliana Azevedo Lima Pallone would like to thank the fnancial support of Brazil (FAPESP 2018/09759–3). The Coordination for the Improvement of Higher Education Personnel (CAPES) (Financial Code 001)