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[Water purification in food industry] Texte intégral
2007
Lovkis, Z.V.,National Academy of Sciences, Minsk (Belarus). Scientific and Practical Center for Foodstuffs | Pranovich, M.V.,Belarus State Technological Univ., Minsk (Belarus)
This article discusses the basic ways of water-preparation in food industry. Water-preparation plan with elements of disinfecting for production of drinking water and drinks is given. The analysis shows that water should meet definite microbiological requirements. In order to reduce its fatal influence on the health of people the clearing and preparation of water are necessary. Development of techniques and means of clearing without chemical technologies, including ozone treatment technologies, allows one to lower and to get rid of application of chemical compounds and reagents. At the moment the ozone treatment water technologies with consequent treatment on filling filters are the most rational. Ozone is the strong oxidant and disinfects water faster than chlorine in some times. With activated carbon use both the flavouring qualities and smell become better. Technology of mutual ozone processing with absorption is the most perspective for water purification and disinfection, possessives a high efficiency in comparison with attitude to pathogen microorganisms, does not lead to the formation of harmful collateral products. Therefore, the questions of development of safe technologies and means for water preparation and treatment are actual and well timed
Afficher plus [+] Moins [-]Water-energy-food nexus: principles and practices
2017
Salam, P.A. | Shrestha, S. | Pandey, Vishnu Prasad | Anal, A.K.
Water-energy-food nexus: principles and practices
2017
Salam, P. A. | Shrestha, S. | Pandey, Vishnu Prasad | Anal, A. K.
Study on filtration characteristics of crude lecithin/water emulsion for food oily waste water treatment
1999
Kawakatsu, T. (Tohoku Univ., Sendai (Japan)) | Nakajima, M. | Ichikawa, S. | Nabetani, H. | Nakajima, M.
As for oily water treatment in food industries, the membrane technology has a large potential to reduce the operation time, equipment space and total costs. Using crude lecithin/water emulsion as a model of oily waste water, filtration characteristics on the flux and total organic carbon (TOC) rejection were investigated with a wide range of membranes in reverse osmosis, nanofiltration, ultrafiltration, and microfiltration. Constant flux and TOC rejection were obtained in crossflow filtration with hydrophilic membranes having smaller pores than the emulsion droplets (1-2 mum). Free phospholipids were removed with reverse osmosis membranes or nanofiltration membranes having high NaCl rejection abilities. When microfiltration membranes having larger pores than the emulsion droplets were used, the membrane characteristics such as the pore structure and hydrophobicity largely affected the filtration characteristics: asymmetric membranes gave relatively high fluxes when its loose side was used against the feed emulsion as a depth filter, symmetric membranes having a spongoid pore structure and a pore size similar to the emulsion droplets brought about almost 0 flux owing to an extreme progress of pore blocking, hydrophobic membranes of adequate pore sizes showed a possibility to result in the negative TOC rejection
Afficher plus [+] Moins [-]Perchlorate as an emerging contaminant in soil, water and food Texte intégral
2016
Kumarathilaka, Prasanna | Oze, Christopher | Indraratne, S.P. | Vithanage, Meththika
Perchlorate (ClO4−) is a strong oxidizer and has gained significant attention due to its reactivity, occurrence, and persistence in surface water, groundwater, soil and food. Stable isotope techniques (i.e., (18O/16O and 17O/16O) and 37Cl/35Cl) facilitate the differentiation of naturally occurring perchlorate from anthropogenic perchlorate. At high enough concentrations, perchlorate can inhibit proper function of the thyroid gland. Dietary reference dose (RfD) for perchlorate exposure from both food and water is set at 0.7 μg kg−1 body weight/day which translates to a drinking water level of 24.5 μg L−1. Chromatographic techniques (i.e., ion chromatography and liquid chromatography mass spectrometry) can be successfully used to detect trace level of perchlorate in environmental samples. Perchlorate can be effectively removed by wide variety of remediation techniques such as bio-reduction, chemical reduction, adsorption, membrane filtration, ion exchange and electro-reduction. Bio-reduction is appropriate for large scale treatment plants whereas ion exchange is suitable for removing trace level of perchlorate in aqueous medium. The environmental occurrence of perchlorate, toxicity, analytical techniques, removal technologies are presented.
Afficher plus [+] Moins [-]Inactivation of Protozoan Parasites in Food, Water, and Environmental Systems
2006
Erickson, M.C. | Ortega, Y.R.
Protozoan parasites can survive under ambient and refrigerated storage conditions when associated with a range of substrates. Consequently, various treatments have been used to inactivate protozoan parasites (Giardia, Cryptosporidium, and Cyclospora) in food, water, and environmental systems. Physical treatments that affect survival or removal of protozoan parasites include freezing, heating, filtration, sedimentation, UV light, irradiation, high pressure, and ultrasound. Ozone is a more effective chemical disinfectant than chlorine or chlorine dioxide for inactivation of protozoan parasites in water systems. However, sequential inactivation treatments can optimize existing treatments through synergistic effects. Careful selection of methods to evaluate inactivation treatments is needed because many studies that have employed vital dye stains and in vitro excystation have produced underestimations of the effectiveness of these treatments.
Afficher plus [+] Moins [-]Evaluación parámetros del proceso de lodos activados generados del tratamiento de agua residual de empresa de alimentos | Evaluation of control parameters for the activated sludge process obtained wastewater treatment in the food facility Texte intégral
2015
Ospina Sangama, Pedro Germán | Ruiz Suárez, Erika Johana
En este estudio se ha planteado la necesidad de evaluar el funcionamiento de proceso biológico utilizando tecnología MBR con el objeto de establecer las condiciones operacionales que permiten obtener un proceso de filtración en las diferentes circunstancias que puedan presentarse. | This study has raised the need to evaluate the performance of the biological process in order to establish operational conditions to obtain filtration process in different circumstances that may arise.
Afficher plus [+] Moins [-]Enhancement of a Spent Irrigation Water Recycling Process: A Case Study in a Food Business Texte intégral
2021
Guillermo Garcia-Garcia | Sandeep Jagtap
Food operations use vast amounts of water. To reduce utility costs as well as concerns regarding water depletion in ecosystems, food businesses usually try to reuse their water. However, this often needs a recycling process to ensure the water is of good quality and safe to reuse in a food environment. This paper presents a case study of a grower of beansprouts and other varieties of sprouted seeds that uses six million litres of water weekly. Approximately 60% of their spent irrigation water is recycled using both 50 µm and 20 µm drum filtration. In addition, chlorine dioxide is used as part of the recycling process as a disinfectant. Our analysis demonstrated that the size of suspended solid particles in over 90% of the cumulative sample tested was smaller than the current 20 µm filter in place, highlighting that the existing system was ineffective. We, then, explored options to enhance the water recycling system of the company. After careful analysis, it was proposed to install a membrane-filtration system with ultraviolet technology to increase the finest level of filtration from the existing 20 µm to 0.45 µm absolute and sterilize any remaining bacteria. This not only improved water quality, but also allowed for the removal of chemicals from the recycling system, delivering both financial and technical improvements.
Afficher plus [+] Moins [-]Efficiencies of polychlorinated bipenyl assimilation from water and algal food by the blue mussel (Mytilus edulis) Texte intégral
1999
Bjork, M. | Gilek, M.
A novel method was used to estimate assimilation efficiencies (AEs) of dissolved and food associated PCBs (IUPAC 31, 49, and 153) by the Baltic Sea blue mussel (Mytilus edulis). Mussels were exposed to radiolabeled PCBs in a series of short-term toxicokinetic experiments at different algal food concentrations, both at apparent steady-state (ASS) and non-steady-state (NSS) conditions in respect to PCB partitioning between water and algae. The PCB AEs were calculated using a physiologically based bioaccumulation model where experimentally determined uptake and exposure rates at ASS and NSS conditions were combined into linear equation systems, which were solved for PCB AE from water and food. A positive relationship between PCB uptake and algae clearance by the mussels was observed for all three PCBs. The PCB AEs from both water and food increased with congener hydrophobicity (octanol/water partition coefficient [K(ow)]), but AEs decreased with increases in water pumping and filtration rate of the mussels, respectively, The average contribution of food-associated PCB to the total uptake also increased with K(ow) from approximately 30% for PCB 31 and PCB 49 to 50% for PCB 153, mainly as a consequence of increased sorption to the algal food.
Afficher plus [+] Moins [-]Development of dynamically formed membrane for recovery of valuable components in waste water from food processing factory.
1985
Watanabe A.