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Mill Wastewater (mill + wastewater)
Kinds of Mill Wastewater Selected AbstractsInfluence of temperature on growth of Scenedesmus obliquus in diluted olive mill wastewater as culture mediumENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 3 2010Gassan Hodaifa Abstract Scenedesmus obliquus can help to reduce the environmental impact of industrial olive mill wastewater from olive oil extraction in the three-phase system. This work examines the effect of temperature changes (288,308,K) on algal growth, culture medium, and biochemical composition of S. obliquus. The maximum specific growth rate of 0.024,h,1 occurred at an optimal temperature of 302.7,K. The apparent activation energies of cell growth and cell death were determined as 61.8 and 142.8,kJ/mol, respectively. At the end of culture the percentages of pigments, proteins, and carbohydrates were greater at the two ends of the temperature range studied, as it was also observed for the maximum elimination of biochemical oxygen demand (BOD5). The mono- and polyunsaturated fatty acid content of the biomass was greater at the lowest temperature used (288,K). [source] Development and application of a fatty acid based microbial community structure similarity indexENVIRONMETRICS, Issue 4 2002Alan Werker Abstract This article presents an index of similarity that has application in monitoring relative changes of complex microbial communities for the purpose of understanding the impact of community instability in biological wastewater treatment systems. Gas chromatographic data quantifying microbial fatty acid esters extracted from biosolids samples can be used to infer the occurrence of changes in mixed culture community structure. One approach to rapidly assess the relative dissimilarity between samples is to calculate a similarity index scaled between 0 and 1. The many arbitrary scales that are associated with the available calculation methods for similarity indices limits the extent of application. Therefore, a specialized index of similarity was derived from consideration of the measurement errors associated with the chromatographic data. The resultant calculation method provides a clear mechanism for calibrating the sensitivity of the similarity index, such that inherent measurement variability is accommodated and standardization of scaling is achieved. The similarity index sensitivity was calibrated with respect to an effective gas chromatographic peak coefficient of variation, and this calibration was particularly important for facilitating comparisons made between different systems or experiments. The proposed index of similarity was tested with data acquired from a recently completed study of contaminant removal from pulp mill wastewater. The results suggest that this index can be used as a screening tool to rapidly process microbial fatty acid (MFA) compositional data, with the objective of making preliminary identification of underlying trends in (MFA) community structure, over time or between experimental conditions. Copyright © 2002 John Wiley & Sons, Ltd. [source] Anaerobic digestion of Aegean olive mill effluents with and without pretreatmentJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 7 2010Gülseren Pekin Abstract BACKGROUND: Olive oil production is an important economical activity in the Aegean region of Turkey. However, the effluents of the olive oil producing mills with their high organic loads and toxic compounds are causing serious environmental problems. The anaerobic biological treatment of olive mill wastewater (OMWW) using the treatment plants of the regional industries could be a method of choice and within the scope of this study floccular and granular sludges were investigated in batch mode for their success in the treatment of OMWW while producing biogas. The major limitation of this treatment is the inhibition of methanogenic bacteria by the phenolic compounds in OMWW. Thus an integrated solution was suggested in which a pre-treatment step (dephenolization) was also introduced before biological step. RESULTS: The effluents of 27 olive mills out of 47 were found to have total phenolics (TP) less than 3 g L,1 and could be treated anaerobically after simple dilution. The biogas production for the untreated OMWW was higher for floccular sludge than for the granular sludge (68.5 mL and 45.7 mL respectively). Combined pre-treatment experiments, first coagulation with polyaluminum chloride, followed by flocculation with cationic polyelectrolyte and finally Fenton's oxidation, could remove 80% of TP and 95% of the total suspended solids. CONCLUSION: OMWW having TP values less than 3 g L,1 can be treated anaerobically using floccular sludge after simple dilution and biogas can be produced. For OMWW samples having higher TP values pre-treatment is necessary and the pre-treatment given in this study may be used effectively. Copyright © 2010 Society of Chemical Industry [source] Anaerobic biodegradation of two-phase olive mill solid wastes and liquid effluents: kinetic studies and process performanceJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 9 2006Rafael Borja Abstract The new two-phase olive oil mills produce three identifiable and separate waste streams, namely (1) the wash waters from the initial cleansing of the fruit, (2) the aqueous solid residues from the primary centrifugation and (3) the wash waters from the secondary centrifugation. As well as offering process advantages, they also consume less water. Therefore the solid residue, two-phase olive mill solid waste (OMSW), has a high organic matter concentration, giving it an elevated polluting load, and cannot be easily handled by traditional technology which deals with the conventional three-phase olive cake. In addition, the new two-phase olive mill effluents (TPOME) are made up of a mixture of effluents (1) and (3), the total volume of TPOME generated being ,0.25 dm3 kg,1 olives processed. This review aims to report the main features and characteristics of two-phase OMSW and TPOME as compared with the classical olive cake and olive mill wastewater (OMW) derived from the three-phase manufacturing process. The advantages and disadvantages of the two-phase decanting process are summarised. The anaerobic digestibility of two-phase OMSW using different influent substrate concentrations is reported. Kinetic studies of anaerobic digestion of two-phase OMSW are also reviewed and summarised, as well as mass balances to predict the behaviour of the reactor and simplified kinetic models for studying the hydrolysis, acidogenic and methanogenic steps of one- and two-stage anaerobic digestion of OMSW. The review also includes the following: assays of anaerobic digestion of wastewaters from the washing of olives, of olive oil and the two together using fluidised beds and hybrid reactors; the kinetics, performance, stability, purification efficiencies and methane yield coefficients. Copyright © 2006 Society of Chemical Industry [source] Olive oil mill wastewater valorisation by fungiJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 9 2006Silvia Crognale Abstract This paper presents a brief survey of studies conducted at the Laboratory of Applied and Environmental Microbiology of the University of Tuscia on the possible biotechnological valorisation of olive mill wastewater (OMW) using fungi. Besides being a serious environmental problem, OMW might be a possible resource owing to the presence of added value products (e.g. antioxidants) and of simple and complex sugars as a basis for fermentation processes. To this end the technical feasibility of various fungal fermentative processes either to obtain products of high added value or to improve its agronomic use has been assessed. With regard to the former aspect the following cases of study are described: production of enzymes, such as lipase by Candida cylindracea NRRL Y-17506, laccase and Mn-dependent peroxidase by Panus tigrinus CBS 577.79 and pectinases by Cryptococcus albidus var. albidus IMAT 4735, and exopolysaccharide production by Botryosphaeria rhodina DABAC-P82. As far as agronomic use of the waste is concerned, a process based on the acidogenic fungus Aspergillus niger NB2 and aimed at increasing the phosphorus content of OMW is also reported. Copyright © 2006 Society of Chemical Industry [source] Response of methanogen populations to organic load increase during anaerobic digestion of olive mill wastewaterJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 9 2006Aurora Rizzi Abstract Process performances of an upflow anaerobic filter treating olive mill wastewater and the response of methanogenic Archaea to increasing volumetric organic load (VOL) were studied. At a VOL of 15 g chemical oxygen demand (COD) L,1 day,1, 90% of the influent COD was removed. Following a VOL increase from 6 to 15 g COD L,1 day,1, the polymerase chain reaction (PCR) titre of hydrogenotrophic Methanobacterium, determined by magnetic capture of the target DNA and group-specific PCR based on the 16S rRNA gene, decreased from 1011 to 108 cells g,1 sludge, while that of Methanomicrobiaceae and relatives increased from 104 to 106 cells g,1 sludge. Methanosaeta -like acetoclastic methanogens were less affected by VOL variation and dominated at high VOL with a 16S rRNA gene PCR titre of 109 cells g,1 sludge. Single-strand conformation polymorphism analysis of the PCR-amplified archaeal 16S rRNA gene showed a stable band pattern, indicating that VOL variation affected the methanogen PCR titre but not the archaeal community structure. Copyright © 2006 Society of Chemical Industry [source] Sequential anaerobic/aerobic biological treatment of olive mill wastewater and municipal wastewaterJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 9 2006Nikolaos Gizgis Abstract This work investigated the efficiency of the combined anaerobic/aerobic biological co-treatment of olive mill wastewater and primary municipal wastewater. A laboratory-scale (6.5 L) upflow anaerobic sludge bed reactor received a mixture of olive mill wastewater and primary municipal wastewater at a loading rate ranging between 3 and 7 kg chemical oxygen demand (COD) m,3 day,1. The input COD concentration ranged between 1800 and 4400 mg L,1. The anaerobic reactor was operated at mesophilic conditions (35 °C). The effluent organic load was between 400 and 600 mg COD L,1, while the suspended solids removal efficiency varied between 75 and 95%. Average biogas production ranged between 3 and 4 L g,1 COD removed. The anaerobic reactor effluent was further treated in a laboratory-scale activated sludge treatment plant. Aerobic treatment reduced the organic load even further to 85,175 mg COD L,1. However, the final effluent still retained a significant level of colour. Removal of colour was possible by ozonation or coagulation. Finally, the treated effluent was non-ecotoxic, as indicated by the Daphnia magna toxicity test. This treatment method showed that it is feasible to treat olive mill wastewater in a municipal wastewater treatment plant by means of a high-rate anaerobic reactor located between the primary clarifier and the aeration tank. Copyright © 2006 Society of Chemical Industry [source] Olive oil mill waste water as a replacement for fresh water in the manufacture of fired clay bricksJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 8 2006Houda Mekki Abstract This paper describes the introduction of olive mill wastewater (OMW) to replace fresh water normally used in clay brick manufacture. OMW is recognised as the major agro-food industry pollutant in the Mediterranean/North African olive-growing region. The research involved adding OMW to laboratory-produced clay bricks following the same making procedure used at a collaborating Tunisian brick factory. The samples containing OMW were found to be comparable in forming/extrusion performance to a control product that used fresh water. If introduced at the factory scale, this innovation would allow a substantial volume of OMW to be recycled, saving on the fresh water currently used in the brick-forming process. During the subsequent brick drying operation, most of the OMW (,98% water) would be released as vapour. Once in the kiln, the remaining solids in the bricks (calorific value 21,23 MJ kg,1) would liberate additional heat, reducing the gross energy from fossil fuel currently required during firing. Copyright © 2006 Society of Chemical Industry [source] Batch and continuous studies on treatment of pulp mill wastewater by Aeromonas formicansJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 6 2001K Gupta Abstract Batch and continuous studies have been conducted on the treatment of black liquor from a kraft pulp and paper mill by a bacterial strain, Aeromonas formicans. The results of batch studies revealed that the strain was able to remove 71% and 78% of COD and lignin respectively, while the colour removal efficiency was around 86% in 10 days of retention time. The analysis of lignin degradation products by gas chromatography after 20 days of incubation revealed the formation of some phenolic acids, which were responsible for the decrease in pH during batch studies. The removal efficiencies of COD, colour and lignin obtained in continuous reactor studies were 73, 88 and 77% respectively for an 8 day detention period and these efficiencies were almost the same as obtained in batch studies. © 2001 Society of Chemical Industry [source] Olive Oil Mill Waste Waters Decoloration and Detoxification in a Bioreactor by the White Rot Fungus Phanerochaeteflavido-albaBIOTECHNOLOGY PROGRESS, Issue 3 2002P. Blánquez Olive oil mill wastewater (OMW) is produced as waste in olive oil extraction. With the purpose of treating this highly polluting waste, a number of experiments were conducted in a laboratory-scale bioreactor with the white rot fungus Phanerochaete flavido-alba ( P.flavido-alba). It is known that this fungus is capable of decolorizing OMW in static or semistatic cultures at Erlenmeyer scale and at 30 °C. The objective of this work was to prove that P. flavido-alba could decolorize OMW in submerged cultures and that it is capable of reducing OMW toxicity at room temperature (25 °C) and in a laboratory-scale bioreactor. In the experiments conducted, manganese peroxidase (MnP) and laccase enzymes were detected; however, unlike other studies, lignin peroxidase was not found to be present. Decoloration obtained after treatment was 70%. The reduction of aromatic compounds obtained was 51%, and the toxicity of the culture medium was reduced by up to 70%. We can therefore state that P.flavido-alba is capable of reducing important environmental parameters of industrial effluents and that prospects are positive for the use of this process at a larger scale, even when working at room temperature. [source] Oxidation of oleuropein studied by EPR and spectrophotometryEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 2 2008Evaggelia D. Tzika Abstract The autoxidation at alkaline pH and enzymatic oxidation by mushroom tyrosinase of oleuropein, the dominant biophenol present in the fruits and leaves of Olea europea, was followed by both electron paramagnetic resonance (EPR) and absorption spectroscopy. For comparison, the same oxidation processes were applied to 4-methylcatechol, a simple polyphenol present in olive mill wastewaters. EPR spectra of stable o -semiquinone radicals produced during autoxidation at pH,12 and short-lived o -semiquinone free radicals produced during autoxidation at pH,9.0 or tyrosinase action and stabilized by chelation with a diamagnetic metal ion (Mg2+) were recorded for both polyphenols, and the corresponding hyperfine splitting constants were determined. The UV-Vis spectral characteristics of the oxidation of polyphenols were highly dependent on the type of polyphenol, oxidant type and the pH of the reaction. The kinetic behavior of tyrosinase in the presence of oleuropein and 4-methylcatechol was followed by recording spectral changes at 400,nm (absorption maximum) over time. The tysosinase activity with oleuropein showed a pronounced pH optimum at pH,6.5 and a minor one around pH,8. From the data analysis of the initial rate at pH,6.5, the kinetic parameters Km = 0.34,±,0.03,mM and Vmax = 0.029,±,0.002 ,A400,min,1 were determined for oleuropein. [source] Kinetics of the degradation by catalytic hydrogenation of tyrosol, a model molecule present in olive oil waste watersJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 9 2003Dominique Richard Abstract Olive mill wastewaters (OMW) constitute an important environmental problem due, among other things, to their high phenolic content. The phytotoxicity of polyphenols makes them resistant to biological treatment. A three-step process comprising adsorption,concentration, catalytic hydrogenation and regeneration on a fixed bed of adsorbent,catalyst was investigated to remove such compounds. Tyrosol (2-(4-hydroxyphenyl)-ethanol) was taken as representative of the polyphenols present in OMW. The catalytic hydrogenation of tyrosol by 30 g kg,1 ruthenium/activated carbon catalyst was carried out in order to establish the reaction mechanism and kinetics necessary for the design of a pilot-scale reactor. Total conversion of tyrosol into non-aromatic compounds was achieved under mild conditions of temperature and pressure. The overall rate of tyrosol removal at 4 MPa and 353 K was . Copyright © 2003 Society of Chemical Industry [source] Involvement of lignin peroxidase in the decolourization of black olive mill wastewaters by Geotrichum candidumLETTERS IN APPLIED MICROBIOLOGY, Issue 1 2005L. Ayed Abstract Aim:, Decolourization of black olive mill wastewaters (OMW) by depolymerization of phenolic compounds by Geotrichum candidum. Methods and Results:, Our results show that G. candidum is able to grow on black OMW supplemented with carbon source and nitrogen. The Geotrichum growth decreased the pH and induced a 49% of colour removal when the black OMW was supplemented with glycerol and diammonium tartrate (20 mm ammonium). An improvement of 10% of colour removal was observed when the culture was supplemented with veratryl alcohol. The decolourization was inhibited with glutamate as nitrogen source. Conclusion:, Our results suggest the potential use of G. candidum in black OMW decolourization and support the concept that lignin peroxidase (LiP) of G. candidum is involved in the depolymerization of phenolic compounds. Significance and Impact of the Study:, This is the first report of LiP production by G. candidum on OMW. [source] | ||||||||||