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Waste Water Treatment (waste + water_treatment)
Selected AbstractsFramework for surface water quality management on a river basin scale: Case study of Lake Iseo, Northern ItalyLAKES & RESERVOIRS: RESEARCH AND MANAGEMENT, Issue 2 2001D. H. A. Al-Khudhairy Abstract River (DESERT) and lake (EVOLA) water quality models are used to simulate the influences of alternative water quality management scenarios on the quality of receiving surface waters in the Lake Iseo basin, Northern Italy. The scenarios are representative of the European Union Directive on Urban Waste Water Treatment (91/271/EEC) and of the regional authority's objective to reduce the total phosphorus loads from point sources entering Lake Iseo and to restore the lake as close as it is practically possible to its former natural qualitative state. Application of DESERT shows that the regional ,Water Clean Up Plan' can achieve similar reductions in total phosphorus concentrations in the basin's main river system, Oglio River, to the 91/271/EEC directive, but at notably lower economic costs. Application of EVOLA to Lake Iseo shows that it is not practical to achieve the regional authority's objective of a specific total phosphorus concentration in the lake by 2016. Instead, the results show that a more realistic, but higher, total phosphorus concentration can be achieved by 2016. The results of both modelling exercises indicate the usefulness of DESERT and EVOLA for comparing and assessing water quality management scenarios and for revising the regional authority's final objectives with regards to total phosphorus concentration in Lake Iseo, as well as the regional ,Water Clean Up Plan' for restoring and safeguarding the quality of the basin's surface waters. [source] Effect of textile waste water on the spermatogenesis of male albino ratsJOURNAL OF APPLIED TOXICOLOGY, Issue 3 2003R. S. Gupta Abstract Textile waste water released from dyeing and printing industries situated in Sanganer, Jaipur (India), brought about inhibition of spermatogenesis in male rats. Water analysis showed the presence of heavy metals at more than permissible limits. Oral administration of waste water to the rats at the dose level of 26.6 ml kg,1 body wt. significantly reduced the weights of testes, epididymides and seminal vesicle. Treated animals showed a notable depression of various stages of spermatogenesis. The production of spermatids was inhibited by 70.8% in waste-water-treated rats. The populations of spermatogonia, preleptotene spermatocytes and secondary spermatocytes were decreased by 67.2, 71.1 and 73.2%, respectively. The total number of Sertoli cells was affected after waste water treatment. Reduced sperm count and motility resulted in treated groups. A significant fall in the content of various biochemical parameters of reproductive tissues was observed after water treatment. Copyright © 2003 John Wiley & Sons, Ltd. [source] Low-temperature (9°C) AMD treatment in a sulfidogenic bioreactor dominated by a mesophilic Desulfomicrobium speciesBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2009Hannele Auvinen Abstract The possibilities for the treatment of low-temperature mine waste waters have not been widely studied. The amenability of low-temperature sulfate reduction for mine waste water treatment at 9°C was studied in a bench-scale fluidized-bed bioreactor (FBR). Formate was used as the electron and carbon source. The first influent for the FBR was acidic, synthetic waste water containing iron, nutrients, and sulfate, followed by diluted barren bioleaching solution (DBBS). The average sulfate reduction rates were 8,mmol,L,1,day,1 and 6,mmol,L,1,day,1 with synthetic waste water and DBBS, respectively. The corresponding specific activities were 2.4 and 1.6,mmol SO,g VSS,1 day,1, respectively. The composition of the microbial community and the active species of the FBR was analyzed by extracting the DNA and RNA, followed by PCR-DGGE with the universal bacterial 16S rRNA gene primers and dsrB -primers specific for sulfate-reducing bacteria. The FBR microbial community was simple and stable and the dominant and active species belonged to the genus Desulfomicrobium. In summary, long-term operation of a low-temperature bioreactor resulted in enrichment of formate-utilizing, psychrotolerant mesophilic sulfate reducing bacteria. Biotechnol. Bioeng. 2009; 104: 740,751 © 2009 Wiley Periodicals, Inc. [source] Advanced dynamical risk analysis for monitoring anaerobic digestion processBIOTECHNOLOGY PROGRESS, Issue 3 2009Jonathan Hess Abstract Methanogenic fermentation involves a natural ecosystem that can be used for waste water treatment. This anaerobic process can have two locally stable steady-states and an unstable one making the process hard to handle. The aim of this work is to propose analytical criteria to detect hazardous working modes, namely situations where the system evolves towards the acidification of the plant. We first introduce a commonly used simplified model and recall its main properties. To assess the evolution of the system we study the phase plane and split it into nineteen zones according to some qualitative traits. Then a methodology is introduced to monitor in real-time the trajectory of the system across these zones and determine its position in the plane. It leads to a dynamical risk index based on the analysis of the transitions from one zone to another, and generates a classification of the zones according to their dangerousness. Finally the proposed strategy is applied to a virtual process based on model ADM1. It is worth noting that the proposed approach do not rely on the value of the parameters and is thus very robust. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] | ||||||||||