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-88. GUDELIS-MATYS K. 2004. Oczyszczanie šcieków w zakładach mięsnych. Gospodarka Mięsna 09: 50-52. KONIECZNY P. SZYMAŃSKI M. 2007. Šcieki przemysłu spożywczego-charakterystyka, zagrożenia, korzyšci, Przegląd Komunalny 02: 88-100. NARDI I.R., Del NERY V., AMORIM A.K.B., SANTOS N.G., CHIMENES F. 2011. Performances of SBR, chemical-DAF and UV disinfection for poultry slaughterhouse wastewater reclamation, Desalination 269: 184-189. NECZAJ E., KACPRZAK M., KAMIZELA T., LACH J., OKONIEWSKA E. 2008. Sequencing batch reactor system for the co-treatment of landfill leachate and

Application of Fenton's Reagent in the Textile Wastewater Treatment Under Industrial Conditions

Application of reactive dyes is very popular in textile industry as these dyestuffs are characterized by good fastness properties. Constapel et al in 2009 estimated the production of this type of dyes for over 140,000 Mg/year. The reactive dyes are mostly (50%) employed for coloration of cellulosic fibers, however they can also be applied on wool and nylon. Unfortunately, they possess a low degree of fixation (50÷90%), since the functional groups also bond to water, creating hydrolysis and the excess of dyes applied cause a colored pollution of aqueous environment. Moreover, dyeing process requires the use of: electrolytes in the form of aqueous solutions of NaCl or Na2SO4 in the concentration up to 100 g/dm3, alkaline environment (pH > 10) and textile auxiliary agents (including detergents). Therefore, the wastewater generated during the reactive dyeing processes is characterized by high salinity, pH value and color, and due to low value of the BOD5/COD ratio are nonbiodegradable. The successful methods of textile wastewater treatment could be Advanced Oxidation Processes (AOPs), amongst which the Fenton reagent seems to be most promising as it is the cheapest and easy in use. Based on the newest literature survey it was found that many successful tests with Fenton reaction were performed mainly in decolorization. However, not enough attention was devoted to decolorization of real industrial wastewater containing dyes, detergents and salts NaCl, or Na2SO4. The experiments carried out in a laboratory scale were focused on the impact of NaCl and textile auxiliary agent (liquid dispersing and sequestering agent) on an inhibition of decolorization process by Fenton's reagent. The objects of the investigation were synthetic mixtures simulating the composition of real textile wastewater as well as the real industrial wastewater generated in the reactive dyeing. The inhibition of the Fenton decolorization in the presence of NaCl and liquid dispersing and sequestering agent was demonstrated. Additional experiments using pulse radiolysis were carried out in order to confirm the inhibition of chloride in the decolorization process.

Wet Oxidation of Dairy Sewage

Results of kinetic studies on the process of wet oxidation of dairy sewage are presented. Experiments were carried out in a stirred batch tank reactor at the oxygen partial pressure equal to 1 MPa and at temperature ranging from 473 to 523 K. Dairy sewage was subjected to oxidation at a natural pH close to 4. The efficiency of decomposition of organic compounds was estimated on the basis of TOC measurement. The highest TOC reduction rate reached 79.6%. A kinetic model of the process was proposed and its parameters were determined experimentally. Good agreement of the experimental and calculated results was obtained.

Abstract

The article presents the results of kinetic studies of the wet oxidation process of dairy sewage. The dairy sewage, obtained straight from the production line, was subjected to oxidation at pH close to the natural value of 7. Experiments were carried out in a stirred batch tank reactor at the oxygen partial pressure equal to 1 MPa and at temperature ranging from 473 to 593 K. The effectiveness of organic compounds decomposition was estimated based on the measurement of TOC. The kinetics of decomposition of milk components, ie lactose, protein and fat, as well as the kinetics of oxidation of intermediate products was the aim of the study. Measurement of the concentration of protein, fat and lactose was done with a milk composition analyzer, calibrated in relation to the dairy sewage. The obtained results were used to develop a mathematical model of wet oxidation of dairy sewage, including the group of analyzed compounds.

Abstract

The important factors that strongly influence the particle size distributions measured by the laser diffraction method are the optical parameters of the suspension (refractive index and absorption coefficient). Knowledge of the values of these parameters is necessary for Mie theory. Mie theory is applied for conversion of the intensity of light recorded on detectors into particle size distribution (PSD) of tested material. Both wastewater and activated sludge are mixtures of a variety of elements (mineral or organic, including living organisms). In practice, it is not possible to define clearly the values of the optical parameters, as the composition of the suspension changes over time. The aim of the study was to estimate the impact of assumed values of the optical parameters on particle size distributions obtained. The PSDs of suspensions sampled in different stages of wastewater treatment are the most reproducible when the following optical parameters are defined: absorption coefficients - 1.0 and the refractive index - 1.52.

Abstract

The Służew Stream, a 14.9 km long watercourse, is part of an ancient river called Sadurka that starts its course in the Warsaw district of Ochota and flows into the Wilanów Lake. In the 19th and 20th centuries, the watercourse received industrial and municipal sewage from Warsaw and its environs, but nowadays only rain and snow meltwater is discharged into the stream. Freshwater sediments of five reservoirs in the catchment area of the Służew Stream - Wilanów Lake, Powsinów Lake, Pond in the Horse Racing area, Lake at Morgi and South Pond in the Wilanów Park - were analysed for the contents of Cr, Cu, Pb, Zn, Ni, Cd and Hg. The following concentrations have been determined: chromium - from 5 to 274 mg/kg, copper - from 5 to 274 mg/kg, lead - from 3 to 310 mg/kg, zinc - from 44 to 1430 mg/kg, nickel - from 3 to 55 mg/kg, cadmium - from 0.3 to 37.3 mg/kg and mercury - from 0.010 to 0.810 mg/kg (Fig. 2-5). The studies have shown that water sediments of Pond in the Horse Racing area, South Pond and Wilanów Lake, supplied by the Służew Stream waters, are characterised by a very high content of heavy metals. In contrast, water sediments of Powsinów Lake and Lake at Morgi, recharged by drainage ditches flowing into the stream, are characterised by much lower concentrations of these elements, but the levels are still much greater than the geochemical background.

mikrobiologiczne. Oznaczanie liczby bakterii w powietrzu atmosferycznym (imisja) przy pobieraniu próbek metodą aspiracyjną i sedymentacyjną. 1989. Polski Komitet Normalizacji Miar i Jakości. Warszawa. PN-89/Z-04111/03. Ochrona czystości powietrza. Badania mikrobiologiczne. Oznaczanie liczby grzybów mikroskopowych w powietrzu atmosferycznym (imisja) przy pobieraniu próbek metodą aspiracyjną i sedymentacyjną. 1989. Polski Komitet Normalizacji Miar i Jakości. Warszawa. PN-77/C-04615/07. Woda i ścieki. Badania mikrobiologiczne. Oznaczanie bakterii grupy coli typu kałowego (feralnego

., SUPRYNOWICZ R. 1994. Study of radioactive contamination of Eastern Poland. Sci. Total Environ. 158, 71-77. CZEKAŁA J. 2008. Osady ściekowe - nawóz czy odpad? Artykuł w formie referatu został wygłoszony na XI Konferencji Naukowo-Technicznej z cyklu Woda - Ścieki - Odpady w środowisku pt. „Kanalizacja-oczyszczalnia ścieków-odbiornik”, 11-13 czerwca 2008 r., Międzyzdroje. DYMACZEWSKI Z., SOZAŃSKI, M., OLESZKIEWICZ J., (red.). 1997. Poradnik eksploatatora oczyszczalni ścieków, II wydanie, PZITS O/Poznań, Lem s.c. Kraków. GAWDZIK J., GAWDZIK B. 2012. Mobility of heavy metals in

: 2403-2410. KURNIAWAN T.A., WAI-HUNG LO, CHAN G. YS. 2006. Physicochemical treatments for removal of recalcitrant contaminants from landfill leachate, Journal of Hazardous Materials B129, 80-100. KWARCIAK A., BOHDZIEWICZ J. 2007. Wpływ pola ultradźwiękowego na intensyfikację oczyszczania odcieków i ścieków syntetycznych w procesie fermentacji metanowej, Materiały X Konferencji „Woda - Ścieki - Odpady w środowisku. Oczyszczanie ścieków i przeróbka osadów ściekowych”, Wydawnictwo Uniwersytetu Zielonogórskiego, 107-115. RODRIGUEZ J. CASTRILLON L., MARANOM E. 2004

REFERENCES BARBUSIŃSKI K. 2005. Toxicity of Industrial Wastewater Treated by Fenton’s Reagent. Polish Journal of Environmental Studies 14, 1: 11-16. BERLAN J., TRABELSI F., DELMAS H., WILHELM A.M., PETRIGNANI J.F. 1994. Oxidative degradation of phenol in aqueous media using ultrasound. Ultrasonics Sonochemistry 1: 97–102. BERNACKI K. 1957. Ścieki fenolowe. Wydawnictwo Budowa i Architektura, Warszawa. CAO G., SHENG M., NIU W., FEI Y., LI D. 2009. Regeneration and reuse of iron catalyst for Fenton-like reactions. Journal of Hazardous Materials 172: 1446–1449. CHANG