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EN
This work is a systematic review of the literature over the past decade of the application of activated carbon (microporous or mesoporous) as adsorbents for the removal of heavy metals, focusing especially on lead (Pb) and arsenic (As) ions from the aqueous phase. Classical examples from our lab are also given. Activated carbon is known to provide a high surface area for adsorption. Generally, surface modification is typically required, such as oxidation, treatment with ammonia or even impregnation with ferric ion, etc. and the adsorbent material may originate from various sources. The pristine materials, after modification and those after batch-wise adsorption, were characterized by available techniques (BET analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, thermal analyses, X-ray photoelectron spectroscopy). Adsorption isotherms, thermodynamics and kinetics of the process are also discussed. Selected studies from the literature are examined in comparison with other adsorbents. The role of chemistry in the metals adsorption/removal was investigated.
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EN
Ferrous metallurgy enterprises have a negative impact on the air, soil, and water environment. The activities of metallurgy enterprises include a wide range of production processes (from the extraction of metals from ores to obtaining finished products) and is associated with the formation of a large amount of waste. Industrial wastewater discharge is the main source of aquatic area pollution. An assessment of the impact of wastewater discharged from the Azovstal Iron & Steel Works metallurgical plant on the state of the coastal waters of the Sea of Azov near Mariupol (Ukraine) is presented in the article. The assessment was carried out in accordance with the current Ukrainian legislation and the adopted methodology for water state assessment. The assessment was based on the available monitoring data of sea water in the area of wastewater discharges in the period 2016–2020. The assessment was carried out using the aggregated numerical indices, as well as taking into account the “limiting criterion principle”. Such a methodological approach allowed for a comprehensive assessment of the sea water quality class as well as its sanitary and ecological condition. The results of the assessment allowed us to ascertain the negative impact of industrial wastewater from the metallurgical plant on the coastal zone of the Azov Sea, which made it unsuitable for communal and recreational purposes.
EN
The dairy industry is one of the most polluting of industries, not only in terms of the volume of effluent generated, but also in terms of its characteristics as well. The composition of waste water produced in the milk processing plants depends primarily on the type of production (such as fluid milk, butter, cheese, buttermilk, whey, yogurt, condensed milk, flavored milk, milk powder, ice cream, etc.). The factors influencing the composition and charge of waste water are the raw materials used, level of technology plant, cleaning and disinfection processes and the amount of water used. Still increased pollution, combined with increased industrial activity and increasingly restrictive laws concerning discharges, focuses on the problem of optimal industry wastewater treatment. High concentration of organic matter in dairy wastewater causes problems with their removal in biological methods. Combining advanced oxidation process (AOP) and biological process has received attention in recent years as a promising alternative for industrial wastewater treatment. Among biological treatment processes the sequencing batch reactor (SBR) have been widely applied for treating dairy wastewater. The advantages of this technology can include high flexibility and ease of adaptation of operating parameters. Sequencing batch reactor is the name given to wastewater treatment systems based on activated sludge, operated on a sequence changes of anaerobic and aerobic conditions in one reactor. Using AOP pretreatment is important to improve the biodegradability and produce an effluent that can be treated biologically These processes involve the generation of highly free radicals, mainly hydroxyl radical (HO) via chemical, photochemical and photocatalytic reactions. One of the most important AOP process is Fenton reaction. Effectiveness of Fenton reaction has been confirmed in the case of pharmaceutical wastewater, treatment of brines or treatment of paper pulp manufacturing effluents. The oxidation system based on the Fenton’s reagent (hydrogen peroxide in the presence of a ferrous salt under acidic conditions) has been used for the treatment of both organic and inorganic substances of the wastewater stream. The present study was aimed to treat the dairy wastewater by Fenton’s process and an aerobic sequencing batch reactor. The first part of this study examined the effect of operating conditions on Fenton`s process pretreatment of dairy wastewater. The effectiveness of the AOP pretreatment was assessed by evaluating wastewater biodegradability enhancement (BOD5/COD), as well as monitoring major pollutant concentrations (COD) with reaction time. The optimum dose Fe2+ and H2O2 was found to be 1.2 and 2.0 g/L, respectively. In a single biological treatment the average removal efficiencies of COD, and NH4+ were 67%, and 61%, respectively. Integration of Fenton`s process and biological treatment resulted in 93% removal of COD and 79% NH4+ from the dairy wastewater. The results indicated that the combined process would be a promising alternative for the treatment of dairy wastewater.
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Content available remote Współczesne metody usuwania chromu ze ścieków
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EN
Technological wastewaters from vegetable fats production belong to the category of industrial ones, containing the biodegradable pollution load. Wastes are mainly substances and compounds of natural origin and phosphates from refining processes. After the appropriate pretreatment they can be agriculturally used for soil irrigation and fertilization. The paper presents results of research on the dynamics of changes in heavy metals concentrations (cadmium, mercury, chromium, nickel, copper, lead and zinc) in surface soil layer from experimental plots, irrigated and fertilized with raw wastewaters and those chemically pretreated with the use of coagulation and hydrogen peroxide aided pressure flotation. Fertilization with wastes from vegetable rat production (mainly from rape oil production) was carried out in accordance with the agricultural practices, in amounts limited by total nitrogen concentration (TN) and the permissible, threshold dose of 170 kgN/ha year. The experiment was being carried out for tour years, measuring the levels of heavy metal contents every month.
PL
Ścieki technologiczne z procesów wytwarzania tłuszczów roślinnych należą do kategorii przemysłowych, zawierających rozkładalny biologicznie ładunek zanieczyszczeń. Zanieczyszczenia stanowią głównie substancje i związki pochodzenia naturalnego oraz fosforany pochodzące z procesów rafinacji. Po stosownym podczyszczeniu mogą być wykorzystane rolniczo na cele nawadniające i nawozowe dla gleb. Przedstawiono wyniki badań nad dynamiką zmian stężenia metali ciężkich (kadm, rtęć, chrom, nikiel, miedź, ołów i cynk) w warstwie przypowierzchniowej gleb z poletek doświadczalnych nawadnianych i nawożonych ściekami surowymi oraz podczyszczonymi chemicznie za pomocą koagulacji i flotacji ciśnieniowej wspomaganej utlenianiem nadtlenkiem wodoru. Nawożenie ściekami z produkcji tłuszczów roślinnych (głównie z produkcji oleju rzepakowego) prowadzono zgodnie z zasadami dobrej praktyki rolniczej, w ilościach limitowanych stężeniem azotu ogółem (N) i dopuszczalną, graniczną dawką 170 kgN/ha rok. Doświadczenie prowadzono na przestrzeni czterech lat, mierząc poziom zawartości metali ciężkich w miesięcznych odstępach czasu.
PL
Omówiono metody oczyszczania ścieków barwnych ze szczególnym uwzględnieniem technik adsorpcyjnych wykorzystujących sorbenty różnego typu, np. węgle aktywne, zeolity, jonity pod kątem ich praktycznego zastosowania w procesie oczyszczania ścieków przemysłu tekstylnego.
EN
A review, with 84 refs., concerning the removal of dyes from aq. solns. and textile wastewaters by adsorption. Various sorbents (activated C, zeolites, ion exchange resins) were described.
EN
Used in wastewater treatment anaerobic dairy use modern methods of anaerobic reactors. Improvements are still sought methods that will enable faster and more efficient dairy wastewater. One of these improvements can be applied to microwave radiation. The solution presented in the article RBMC microwave reactor is used to stimulate the anaerobic digestion process. The obtained results allow to evaluate the potential use of microwaves to the development of thermal conditions in a reactor operating at an industrial scale. The aim of this study was to determine the effectiveness of the methane fermentation of whey at a temperature of 35 deg. C using an anaerobic reactor with microwave heating system. In the course of the work carried out two related research objectives: the analysis of the efficiency of the fermentation reactor with an innovative hybrid design and study the impact of the method of heating the reactor to the process. Terms construction and reactor technology used RBMC allowed to conduct research in a convection heating and microwave. Conducted research aimed to validate or exclude the presence athermal effects of microwave effects on the process of wastewater treatment. In order to demonstrate the effect of microwaves on the process of anaerobic digestion of whey in mesophilic conditions, tests were carried out in two stages with different heating process of fermentation. In the first stage, the reactor was heated using a microwave generator, while the second uses a water jacket, and the heating takes place by convection. In each of the stages identified five series of different sizes of cargo delivered OLR organic compounds in the range of 5 to 25 kg COD/(m3∙d). The analyzes carried out showed that the applied microwave heating significantly affect the efficiency of whey disposal, but this effect was observed in the higher ranges of the reactor load (series 3, series 4, series 5). The use of microwave radiation had a significantly higher number of resulting biogas and removal efficiency of chemical oxygen demand at a load of 15 g COD /(L∙d) and higher. The most effective in terms of technological operation of the reactor was load of 15 g COD /(L∙d) Under these conditions, resulting in high efficiency contaminant removal with a considerable amount of biogas rich in methane. At the same time the concentration of total suspended solids in the effluent did not exceed 1000 mg /L. The results show that the use of microwaves in wastewater treatment may be an effective improvement classic methods.
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Content available remote Usuwanie fenolu z wód ściekowych przez utlenianie
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Content available remote Technologie usuwania i odzyskiwania fosforanów ze ścieków
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PL
Zwrócono uwagę na konieczność odzyskiwania fosforanów ze ścieków przemysłowych i komunalnych. Przedstawiono proponowane i stosowane rozwiązania technologiczne związane z biologiczną i chemiczną eliminacją fosforanów. Omówiono wady i zalety tych metod.
EN
A review with 42 refs. covering biological and Chemical treatment procedures, suggested phosphate recovery processes, recycling problems and related factors.
PL
Badano efektywność usuwania siarczanów(VI) ze ścieków poprzez ich wytrącanie w postaci minerału etryngitu. Wykorzystano cementy glinowo-wapniowe Górkal 40 (G40) i Górkal 70 (G70), stanowiące źródło jonów glinu i wapnia, niezbędnych do tworzenia się etryngitu. Badano wpływ czasu reakcji i dawki cementów na skuteczność usuwania siarczanów ze ścieków syntetycznych zawierających ok. 1000 mg SO4 2-/dm3. Wstępne badania na ściekach syntetycznych wykazały, że cementy G40 i G70 mają podobną skuteczność usuwania siarczanów. Do dalszych badań wybrano cement G40, który przy mniejszych dawkach okazał się skuteczniejszy, a jednocześnie charakteryzował się niższą ceną. Oprócz dawki cementu (a tym samym dawki glinu) oraz czasu reakcji badano również wpływ pH na skuteczność wytrącania siarczanów (formowania etryngitu). Zastosowanie cementu G40 w dawce 3,68 g/dm3., pH 12, czasu reakcji 180 min pozwoliło na usunięcie siarczanów ze ścieków syntetycznych (zawierających 1000 mg SO4 2-/dm3.) do poziomu 40 mg SO4 2-/dm3. (96,0% usunięcia). Następnie zbadano skuteczność powyższej metody do oczyszczania ścieków zawierających siarczany(VI) w ilości 2475 mg/dm3 odprowadzanych podczas produkcji zapałek. Ścieki zostały podczyszczone wcześniej z innych zanieczyszczeń w przyzakładowej oczyszczalni metodą Fentona (FeSO4 + H2 O2). Dla dawki cementu 3,8 g/dm3., pH 12 oraz czasu reakcji 180 min uzyskano stężenie siarczanów(VI) na poziomie 30 mg/dm3., co odpowiadało 98,8% usunięcia.
EN
Synthetic and real wastewaters from match prodn. were treated with Al-Ca cements (up to 60 g/L) at pH 8.0–12.5 under stirring for 300 min (150 rpm) to remove SO4 2- ions (initial concn. 910–2475 mg/L). The gypsum precipitate was sepd. by sedimentation, filtration and centrifugation. The gypsum removal degree increased with increasing the cement dose and stirring time and showed a max. at pH 12.0 (near 100%).
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Content available remote Rozkład stężonej mieszaniny detergentów pod działaniem odczynnika Fentona
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PL
Silnie stężone ścieki zawierające znaczne ilości detergentów są trudne do oczyszczania klasycznymi sposobami, zwłaszcza metodami biologicznymi. Wśród procesów mogących pomóc w rozwiązaniu tego problemu znajduje się utlenianie z wykorzystaniem odczynnika Fentona, w skład którego wchodzi nadtlenek wodoru i jony żelaza dwuwartościowego. Mieszaninę detergentów komercyjnych: Empilanu, Empicolu i Trilonu o sumarycznym stężeniu 3,75% wag. poddano utlenianiu odczynnikiem Fentona uzyskując redukcje chemicznego zapotrzebowania na tlen (ChZT) powyżej 90%. Następował także wzrost podatności ścieku na biodegradację. Zbadano wpływ stężenia soli żelaza(II) oraz nadtlenku wodoru, czasu i sposobu prowadzenia procesu oraz rodzaju soli – FeSO4 i FeCl2.
EN
FeSO4·7H2O was dissolved in a 3.75% model wastewater contg. (1.25% of each) coconut oil fatty acids diethanolamide R-CON-(CH2CH2OH)2 (R = C12-C18), ethoxylated lauryl (alkyl) Na sulfate CH3-(CH2)n-(O-CH2-CH2)p-OSO3-Na (n = 9-15, p = 2), and tetrasodium versenate. The mixt. was adjusted with HCl to pH 2, treated with 30% H2O2, with NaOH to pH 12, decanted in 24 hrs., and filtered. Optimum sulfate and peroxide amts. were 230 cm3 and 130 g per 0.5 l. wastewater. COD, 35300 mg O2/l., was reduced in 92%. The treatment made wastewater more apt. to biodegrade, BOD/COD ~0.6 vs. the original 0.2. Anionics fell below 2% of the original amt., chlorides rose by a factor of 2.5. The resulting Fe(OH)3 sorbed original contaminants and their oxidates. Organics desorbed easily and were as biodegradable as the starting wastewater.
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Content available remote Regularities of adsorption of α-oxypropionic acid by natural zeolite
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EN
Wastewaters from dairy processing factories contaminated with α-oxypropionic acid were monitored. Theoretical analysis of industrial wastewater treatment methods on zeolites of Sokyrnytsia deposit was carried out. The process of sorption of α-oxypropionic (α-oxypropionic) acid by natural zeolite of Sokyrnytsia deposit was considered. It was established that the most economically advantageous and safe is the method of adsorption using a natural sorbent - zeolite, which provides the lowest concentration of contaminants in treated wastewaters from dairies. An assessment of their number, localization features and measures of toxicological impact on the environment was done. The existing theoretical apparatus of description of adsorption processes was analyzed. The sorption properties of natural zeolite (clinoptilolite of Sokyrnytsia deposit) and activated carbon to α-oxypropionic acid were tested. Equilibrium values of adsorption capacity were calculated and corresponding isotherms at a temperature of 20° С were constructed. The porosity of the sorbent and its influence on the sorption properties were studied by the methods of physicochemical analysis. Infrared spectroscopic and electron microscopic studies confirmed the presence of the process of sorption by the surface of the internal pores of the zeolite of α-oxypropionic acid molecules. Experimental studies have confirmed the possibility of using natural zeolite for wastewater treatment of dairy factories. It was experimentally confirmed by physicochemical methods of analysis (electron microscopy, IR spectroscopy, microprobe analysis, mercury porometry) and was established that the process takes place both by the mechanism of ion exchange and physical adsorption. The content of carbon radicals in the zeolite matrix after the sorption process was confirmed by X-ray spectral microanalysis. The ability of zeolite to adsorb organic carboxylic acid radicals was confirmed by the results of IR spectroscopic studies. On the IR spectra there are strips of deformation and valence oscillations of the groups of the crystal lattice of the zeolite Si-O, Si-O-SiOH: 452, 990–1210, 1638, 3368 cm-1. The oscillation spectra of free OH groups in the region of 2600 cm-1 were revealed.
PL
W pracy podjęto próbę wykorzystania czterech szczepów grzybów strzępkowych Rhizopus oligosporus do biodegradacji ścieków z przemysłu krochmalniczego po uprzednim przetestowaniu ich na podłożu modelowym imitującym ścieki ziemniaczane. Do oczyszczania ścieków zastosowano mikroorganizmy, które posiadają szerokie zastosowanie do produkcji żywności fermentowanej i są bezpieczne dla organizmu ludzkiego jak i dla środowiska.
EN
The study attempts to use four strains of Rhizopus oligosporus for biotreatment of wastewater from potato starch industry. First the strains were tested on model medium imitating potato wastewater and than on industrial wastes. The Rhizopus mold applied in the experiments is widely used in the production of fermented foods and is recognized as safe for humans and the environment.
PL
Zakłady przemysłu spożywczego zużywają duże ilości wody. Ponad 90 % wody zostaje przekształcone w ścieki, co może oznaczać wysokie potencjalne zagrożenie dla środowiska naturalnego. Użyciu takich związków chemicznych jak: sole żelaza lub glinu oraz polielektrolity, towarzyszy koagulacja i flokulacja cząstek koloidalnych zawartych w ściekach wybranych branż. Można oczekiwać, że użycie wymienionych związków będzie związane z kilkoma innymi korzyściami jak: zmniejszenie zawartości fosforu ogólnego, minimalizacja problemów zapachowych lub poprawa właściwości osadu. W prezentowanej pracy podjęto próbę porównania, w tych samych warunkach analitycznych, skuteczności działania siarczanu żelazowego Fe(III) jako koagulanta ( dawka: 450 g/m3) w chemicznym oczyszczaniu surowych ścieków technologicznych, pobranych w trzech różnych zakładach przemysłu spożywczego (mleczarskich, mięsnych i rybnych). Wyniki oceny wizualnej i oznaczenia chemiczne w ściekach po koagulacji wykazały znaczącą poprawę wybranych parametrów ścieków, chociaż podatność badanych ścieków na działanie koagulanta była zróżnicowana. Stopień redukcji poszczególnych parametrów ścieków mieścił się w szerokim zakresie od 20,9 do 97,2 %.
EN
Food processing plants need usually large quantities of clean water. More than 90 % of clean water is there converted into wastewater and this may mean a high potential risk of environmental pollution. Using chemical products such as iron or aluminum salts and polyelectrolytes is associated with a coagulation and flocculation of the colloidal particles in wastewater from selected branches. Some of the additional benefits for the use of such chemicals like reduction of total phosphorus content, minimization of odour problem and improvement of sewage sludge properties are expected. The present study was also undertaken to compare, under the same analytical conditions, the efficiency of ferric sulfate Fe (III) used as coagulant (dose: 450 g/m3) in chemical treatment of raw technological wastewater collected from three various food industry plants (dairy processing, meat processing and fish processing). Results of visual and physicochemical evaluation of chemically treated wastewater indicated significant improvement of their selected characteristics, however different response to the coagulant treatment was observed within tested samples. Removal efficiencies for individual parameters varied in the wide range between 20,9 and 97,2 %.
EN
The analysis of bacteriological contamination of the meat industry wastewater treatment plants at the individual stages of treatment was the aim of these investigations. The experiments were carried from February, 2002 to January, 2003. Samples were taken seven times from the following treatment stages: after mechanical pretreatment, after the use of perhydride, and after biological treatment. Quantitative and species analyses were done including the bacteria family of: Enterobacteriaceae, streptococci, and staphylococci. The analyzed meat industrial wastewaters were characterized by significant microbial contamination. The Enterobacteriaceae were found at 10[5] - 10[7] pcs/ml, the Staphylococci: 10[4] - 10[5] pcs/ml, the Streptococcus faecalis: 10[4] - 10[5] pcs/ml. The following bacteria species were most frequently identified in the analyzed wastewater samples: Escherichia coli, Salmonella spp, Citrobacter freundii, Streptococcus faecalis, Streptococcus faecium, Staphylococcus lentus, Staphylococcus aureus, Staphylococcus xylosus, Staphylococcus sciuri. The use of perhydride significantly decreased the amount of bacteria in wastewater. In the wastewater, after biological treatment, pathogenic bacteria were separated. Their disposal into natural water-courses is hazardous for people and animals.
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