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Tytuł:
Contaminants Removal from Real Refinery Wastewater Associated with Energy Generation in Microbial Fuel Cell
Autorzy:
Jabbar, Noor Mohsen
Alardhi, Saja Mohsen
Al-Jadir, Thaer
Dhahad, Hayder Abed
Powiązania:
https://bibliotekanauki.pl/articles/2202351.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
microbial fuel cell
phenol
furfural
power generation
COD
chemical oxygen demand
petroleum refinery wastewater
Opis:
Microbial fuel cells (MFCs) pertain to a kind of modern technology for the direct conversion of chemical energy in organic matter from wastewaters into electricity during the oxidation of organic substrates. A system of continuous MFC was constructed for the treatment of real petroleum refinery wastewater (PRW). The treatment of real PRW, operational performance of the MFC system, biodegradation of furfural, and energy output were investigated in this study. The MFC was inoculated by mixed anaerobic bacteria, with Bacillus sp. as the dominant type, and continuously operated for 30 days. The biodegradation of furfural and phenol, which are the most prevalent toxicants in refinery wastewater, was investigated. The MFC system reached maximum energy outputs of 552.25 mW/m3 and 235 mV. In the anodic chamber, the maximum removal of furfural and phenol was higher than 99%, with biodegradation of organic content reaching up to 95%. This study demonstrated the viability of a continuous-flow MFC system as a green technology for the treatment of furfural-rich real refinery effluents while generating electricity.
Źródło:
Journal of Ecological Engineering; 2023, 24, 1; 107--114
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
FE2(SO4)3 and Bentonite Use to Reduce Cod Indicators in Wastewater Containing Detergents
Autorzy:
Issayeva, Akmaral
Abubakirova, Azhar
Syzdykova, Marzhan
Arystanova, Saltanat
Anlamasova, Gulnara
Zhumakhanova, Roza
Leska, Boguslawa
Powiązania:
https://bibliotekanauki.pl/articles/2068458.pdf
Data publikacji:
2022
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
wastewater
chemical oxygen demand
ferric iron
bentonite
Opis:
Wastewater pollution with detergents is one of the environmental problems associated with the rational use of water resources. The existing methods of physicochemical wastewater treatment, despite their efficiency, are open to secondary environmental pollution. Biological coagulation/flocculation methods are widely used with the plant waste. The aim of this research was the use of ferric iron obtained by means of the bacterial-chemical method and bentonite to reduce the chemical oxygen demand in the wastewater containing detergents. It was identified that the use of Fe2 (SO4)3 obtained using the bacterial-chemical method with thionic bacteria Acidithiobacillus ferrooxidans BIT 1 and bentonite as a clay material is promising. At the same time, it was found that the highest reduction degree in the chemical oxygen demand – 88.1 ± 7.9% in wastewater was noted in the variation where the bacterial-chemical ferric iron in the amount of 1.75 g/L was used in combination with bentonite in the amount of 600 mg/L.
Źródło:
Journal of Ecological Engineering; 2022, 23, 3; 68--73
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Treatment of wastewater from the production of meat and bone meal by the Fenton process and coagulation
Autorzy:
Makara, Agnieszka
Kowalski, Zygmunt
Radomski, Piotr
Olczak, Piotr
Powiązania:
https://bibliotekanauki.pl/articles/2174824.pdf
Data publikacji:
2022
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
wastewater
meat and bone meal
Fenton process
coagulation
chemical oxygen demand
Opis:
Wastewater from the production of meat and bone meal, due to the high load of organic matter and suspended solids, is a significant problem in the process of its treatment. In this work, we examined the method of treating this wastewater using coagulation with hydrogen peroxide and the Fenton process. Treatment variants included the use of variable Fe2+/H2O2 ratios of 1:5–1:30, variable doses of 3–18.0 g/L H2O2, and 5–10 mL/L of coagulant PIX 113. The calculated reduction degrees showed that, regardless of the treatment variant used, the greatest reduction was obtained for turbidity (100%), phosphorus (99%), followed by color (97%), chemical oxygen demand (70%), and Kjeldahl nitrogen (48%). The proposed treatment options can be used as a preliminary stage in treating wastewater from the production of meat and bone meal.
Źródło:
Polish Journal of Chemical Technology; 2022, 24, 4; 51--60
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Annual Variation in the Performance of Settat Wastewater Stabilization Ponds Located in Settat City, Morocco
Autorzy:
Dyaa, Abou-Tammame
Jihane, Fathi
Abdelhamid, Bouzidi
Powiązania:
https://bibliotekanauki.pl/articles/1955490.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
wastewater
natural lagoon
biochemical oxygen demand
chemical oxygen demand
suspended solids
sewage treatment
wastewater reuse
agriculture
Opis:
The wastewater treatment plant of Settat city uses the natural lagooning technology, which requires low maintenance cost and little technical expertise. The purpose of this study was to evaluate the stability of plant performance during two years of operation (2019 and 2020), as well as the safety of its treated wastewater for reuse in agricultural irrigation. The results of this study show that the biochemical oxygen demand (BOD5), chemical oxygen demand (COD) and suspended solids (SS) did not exceed the Moroccan standards for discharge. They also show a good stable pollutant load reduction with a mean of 86.44%, 86.89% and 74.61%, for BOD5, COD and SS, respectively. On the other hand, microbiological characterization classifies the treated wastewater as "B" quality water, because the fecal coliform numbers exceed the requirement for "A" quality (1000 CFU/100 ml).
Źródło:
Journal of Ecological Engineering; 2021, 22, 8; 153-164
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Disintegrating Influence of Sonication on the Excess Sludge Liquification and their Microbiological Indicator
Dezintegrujący wpływ sonifikacji na upłynnienie osadów nadmiernych oraz ich wskaźniki mikrobiologiczne
Autorzy:
Zawieja, Iwona
Brzeska, Kinga
Powiązania:
https://bibliotekanauki.pl/articles/1811761.pdf
Data publikacji:
2019
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
excess sludge
ultrasonic field disintegration
soluble chemical oxygen demand
SCOD
methane fermentation
microbiological indicators
osady nadmierne
dezintegracja ultradźwiękowa
rozpuszczone chemiczne zapotrzebowanie na tlen
ChZT
fermentacja metanowa
wskaźniki mikrobiologiczne
Opis:
The rate of decomposition of organic matter during methane fermentation is limited by the speed of the first phase of this process, called hydrolysis, during which liquefaction process of organic compounds takes place. For the pre-treatment of sludge before methane fermentation, disintegration techniques are used, which depending on the type of energy supplied to the system, can be divided into four groups: chemical, thermal, mechanical, biological methods. An effective method of mechanical disintegration of sewage sludge is the technology associated with the use of ultrasound. The impact of ultrasonic waves distorts the state of balance in the system, leads to better spatial packing of molecules, changing the structure of sewage sludge and their physico-chemical properties. The aim of the study was to determine the disintegrating influence of sonication on the excess sludge liquification expressed as the increase in the soluble chemical oxygen demand (SCOD) value of the modified excess sludge as well as estimating of the microbiological indicators of sonicated sludge. The process of disintegration of excess sludge with the ultrasonic field was carried out with the use of a disintegrator type UD-20 with a vibration frequency of 22 kHz and a maximum output power of 180W. Microbiological analyzes performed for non-modified and disintegrated sludge concerned the number of mesophilic and psychrophilic microorganisms, Salmonella spp bacteria and Escherichia coli type bacteria, which is a pathogenic species. Periodic methane fermentation of excess sludge was carried out for 10 days, in the temperature of 37°C. As a result of subjecting the excess sludge to disintegration with an ultrasonic field, an increase in the degree of liquefaction of sludge was noted, expressed as an increase in the value of soluble chemical oxygen demand (SCOD). For the vibration amplitude of 16μm and sonication time of 300 s about 5-fold increase of SCOD values in relation to initial values was obtained. The highest degree of elimination of the studied groups of microorganisms was noted on the 10th day of the methane fermentation process of modified excess sludge.
Szybkość rozkładu substancji organicznych podczas fermentacji metanowej jest ograniczona szybkością pierwszej fazy tego procesu zwanej hydrolizą, podczas której następuje upłynnienie związków organicznych. W celu wstępnej modyfikacji osadów przed fermentacją metanową stosuje się techniki dezintegracji, które w zależności od rodzaju energii dostarczanej do układu można podzielić na cztery grupy: chemiczne, termiczne, mechaniczne, biologiczne. Skuteczną metodą mechanicznej dezintegracji osadów ściekowych jest technologia związana z zastosowaniem ultradźwięków. Oddziaływanie fal ultradźwiękowych zakłóca stan równowagi w układzie, prowadzi do lepszego przestrzennego upakowania cząsteczek, zmieniając przy tym strukturę osadów ściekowych oraz ich właściwości. Celem badań było określenie dezintegrującego wpływu sonikacji na upłynnienie osadów nadmiernych wyrażone wzrostem wartości rozpuszczonego chemicznego zapotrzebowania na tlen (ChZTrozp.), a także oszacowanie wskaźników mikrobiologicznych sonifikowanych osadów. Proces dezintegracji osadów nadmiernych polem ultradźwiękowym przeprowadzono przy użyciu dezintegratora typu UD-20 o częstotliwości drgań 22 kHz i maksymalnej mocy wyjściowej 180 W. Analizy mikrobiologiczne przeprowadzone dla osadów niemodyfikowanych i dezintegrowanych dotyczyły określenia liczebności mikroorganizmów mezofilnych i psychrofilnych, bakterii Salmonella spp i bakterii typu Escherichia coli, która jest gatunkiem patogennym. Okresową fermentację metanową osadów nadmiernych prowadzono przez 10 dób, w temperaturze 37°C. W wyniku poddania osadów nadmiernych modyfikacji za pomocą pola ultradźwiękowego odnotowano wzrost stopnia upłynnienia osadów, wyrażony wzrostem wartości rozpuszczonego chemicznego zapotrzebowania na tlen. Dla amplitudy drgań 16 μm i czasu sonikacji 300 s uzyskano około 5-krotny wzrost wartości ChZTrozp. w stosunku do wartości początkowych. Najwyższy stopień eliminacji badanych grup mikroorganizmów odnotowano w 10 dobie procesu fermentacji metanowej modyfikowanych osadów nadmiernych.
Źródło:
Rocznik Ochrona Środowiska; 2019, Tom 21, cz. 1; 456-471
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Economic Valuation and Effectiveness of Utilizing Electrocoagulation System in Reducing Chemical Oxygen Demand of Textile Industry Wastewater
Autorzy:
Fikri, Elanda
Sintawati, Nita
Ruhmawati, Tati
Powiązania:
https://bibliotekanauki.pl/articles/125280.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
economic valuation
electrocoagulation
Chemical Oxygen Demand
COD
textile industry
Opis:
Industrial activities vary greatly. The textile industry processes produce solid and liquid waste. The liquid waste comes from the process of reviewing threads, removing lubricants from synthetic fibers before weaving, and from the dyeing process. The purpose of this research is to determine the economic valuation and effectiveness of utilizing an electrocoagulation system in reducing Chemical Oxygen Demand (COD) of the textile industry wastewater. This research is a kind of an experimental study involving the pretest and posttest without control design. The research strategy consisted in 9 volt voltage and 5A electric current density with a 3 cm electrode plate distance. The container used in electrocoagulation process was made of plastic with the dimensions of 48.5×27.5×31 cm. The sampling technique was grab sampling with 3 treatments and 6 repetitions. The sample size was 45 liters. The results of this research indicate that the electrocoagulation method can reduce the level of Chemical Oxygen Demand (COD) in the textile production wastewater. The COD level before treatment was 221.5 mg/l, after electrocoagulation with 8 electrode plates dropped to 23.0–41.0 mg/l (85.26% decrease). The economic effectiveness and efficiency of the use of electrocoagulation compared to using conventional method in reducing COD level is only Rp 47.59/liter, while the conventional method reaches Rp 117.089/liter.
Źródło:
Journal of Ecological Engineering; 2019, 20, 8; 35-43
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Thermal and Alkaline Disintegration of Excess Sludge on Biodegradation
Autorzy:
Zawieja, Iwona
Powiązania:
https://bibliotekanauki.pl/articles/952398.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
volatile fatty acids
excess sludge
thermal disintegration
alkaline disintegration
soluble chemical oxygen demand
SCOD
total organic carbon
TOC
VFAs
methane fermentation
Opis:
Thermal methods of sludge disintegration can be divided into high temperature (over 100°C) and low temperature (below this temperature). They consist in the supply or removal of thermal energy, contributing to the changes in sludge structure and physicochemical properties. During the chemical disintegration of excess sludge with sodium hydroxide, there is an increase in the pH value, as well as changes in their structure. The OH- ions are highly toxic to the microorganisms living in the excess sludge and affect the decline of biological activity of most microorganisms. The aim of the conducted research was to prove the impact of the thermal and alkaline disintegration of excess sludge on the susceptibility of organic substances to biodegradation. The thermal disintegration of excess sludge was carried out in a shaking water bath, in which the sludge placed in laboratory flasks with an active volume of 0.5 L were heated for a specified period within the scope of the so-called low temperatures, i.e. 65–95 °C. The sludge was heated for a period of 0.5–12 h. The alkaline disintegration of the sludge was carried out with sodium hydroxide in the form of dust at ambient temperature, in sealed plastic bottles with an active volume of 5L, the contents of which were mixed manually every few hours. The regent doses in the range of 0.05–1.3 g NaOH/g VSS and disintegration time 12h were used. As a result of subjecting the excess sludge to disintegration by means of the selected methods, an increase in the concentration of organic substances in the dissolved form in the supernatant liquid was noted. On the basis of the increase in SCOD, TOC value and VFAs concentration, the most favorable modification conditions were determined. As a result of disintegration of the sludge and subsequent methane fermentation, the supporting effects of the applied modification methods were observed, in relation to the conventional methane fermentation of excess sludge.
Źródło:
Journal of Ecological Engineering; 2019, 20, 10; 172-182
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of catalytic processes for biodiesel production wastewater treatment
Autorzy:
Borralho, Teresa
Coelho, Solange
Estrelo, Andreia
Powiązania:
https://bibliotekanauki.pl/articles/205024.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
cobalt
chemical oxygen demand
Fenton process
biodiesel production wastewater
catalytic advanced oxidation process
potassium monopersulphate
Opis:
The study of the possibility of removing organic compounds from wastewater originating from the biodiesel purification stage by two catalytic processes, HSO5-/transition metal and Fenton method has been presented. The source of the ion HSO5-is potassium monopersulphate (2KHSO5∙KHSO4∙K5SO4) (Oxone) that may be decomposed into radicals (OH., SO4-., SO5-.) by means of transition metal as Co(II). Different concentrations were used for both compounds and the combination ([Co2+] = 1.00μM/[HSO5-] = 5.00·10-2 M) achieved the highest COD removal (60%) and complete decomposition of the oxidant was verified for contact times of 45 min. This process has some advantages comparing to the conventional Fenton method such as the absence of the costly pH adjustment and the Fe(III) hydroxide sludge which characterize this treatment process. The Fenton process showed that the combination of [H2O2] = 2.00M/[Fe2+] = 0.70 M was the best and archived COD removal of 80%. The treatments studied in this research have achieved high COD removal, but the wastewater from the biodiesel purification stage presents very high parametric values of Chemical Oxygen Demand (667,000 mgO2/L), so the final COD concentration reached is still above the emission limit of discharge in surface water, according the Portuguese Law (Decree-Law 236/98). However, both treatments have proved to be feasible techniques for the pre-oxidation of the wastewater under study and can be considered as a suitable pre-treatment for this type of wastewaters. A rough economic analysis of both processes was, also, made.
Źródło:
Archives of Environmental Protection; 2019, 45, 2; 66-72
2083-4772
2083-4810
Pojawia się w:
Archives of Environmental Protection
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Analysis of the Amount of Pollutants in Wastewater after Mechanical Treatment in the Aspect of their Susceptibility to Biodegradation in the Treatment Plant in Nowy Targ
Autorzy:
Nowobilska-Majewska, Elwira
Bugajski, Piotr
Powiązania:
https://bibliotekanauki.pl/articles/123918.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
wastewater
biodegradability
mechanical treatment
BOD5
COD
chemical oxygen demand
biochemical oxygen demand
total nitrogen
total phosphorus
Opis:
The aim of this study was to determine the biodegradability of organic and biogenic contaminants in wastewater flowing into biological reactors in the treatment plant in Nowy Targ. The research period covered the years 2016 and 2017, when 87 samples of raw wastewater and 87 samples of wastewater after mechanical treatment were collected and subjected to physico-chemical analysis. In both types of wastewater, the size of the following indicators was analyzed: BOD5, COD, total kjeldahl nitrogen (TN) and total phosphorus (TP). The study verified the amount of pollutants in the raw wastewater in order to determine whether they are household wastewater. In the next stage of the analysis, the characteristic values of the analyzed indicators in wastewater after the mechanical treatment process were determined in order to indicate mutual dependences of organic and biogenic indicators. Based on the analysis, it was found that wastewater after mechanical treatment (in the case of its susceptibility to biological decomposition processes of organic pollutants) has an unfavorable COD/BOD5 ratio. With regard to the susceptibility of wastewater to nitrification, denitrification and dephosphatation processes, in the majority of cases, wastewater is susceptible to these processes. It is recommended to apply an additional source of organic carbon to wastewater prior to biological treatment in order to improve the biodegradation of the analyzed pollutants.
Źródło:
Journal of Ecological Engineering; 2019, 20, 8; 135-143
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wastewater Treatment Methods for Effluents from the Confectionery Industry – an Overview
Autorzy:
Zajda, Magdalena
Aleksander-Kwaterczak, Urszula
Powiązania:
https://bibliotekanauki.pl/articles/124113.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
confectionery industry
wastewater treatment
biological oxygen demand
chemical oxygen demand
low-cost material
Opis:
Wastewater from the confectionery industry is characterized by daily and seasonal variability of composition and quantity which adversely affects the process of their disposal. Confectionery plants discharge about 300-500 m3 per month of technological wastewater. Sewage from the confectionery industry belongs to biologically degradable. It is characterized by high values of chemical oxygen demand (COD) and biological oxygen demand (BOD). The article reviews various methods used to treat wastewater from the confectionery industry. Attention was paid to the applicability of a particular method, its advantages and disadvantages and the costs of implementation. The technology of industrial wastewater treatment uses both mechanical and physicochemical methods as well as biological ones. Techniques of sewage treatment usually consist of several stages which use different processes. Low-cost materials such as natural minerals, agricultural waste, industrial waste, biosorbents, and others contribute to the improvement of aerobic sewage conditions. The main weakness of typical sewage treatment plants is their large area, high investment, and exploitation costs. Therefore, a good solution may be the use of the membrane biological reactor which combines the classical technique of activated sludge and filtration on micro-filtering membranes.
Źródło:
Journal of Ecological Engineering; 2019, 20, 9; 293-304
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Dry Ice Modification of Excess Sludge on the Methane Fermentation Process
Wpływ modyfikacji osadów nadmiernych suchym lodem na proces fermentacji metanowej
Autorzy:
Zawieja, I.
Powiązania:
https://bibliotekanauki.pl/articles/1813646.pdf
Data publikacji:
2018
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
excess sludge
methane fermentation
disintegration
dry ice
volatile fatty acids
VFAs
soluble chemical oxygen demand
SCOD
total organic carbon
TOC
osady nadmierne
fermentacja metanowa
dezintegracja
suchy lód
lotne kwasy tłuszczowe
LKT
chemiczne zapotrzebowanie na tlen
ChZT
ogólny węgiel organiczny
OWO
Opis:
The specific susceptibility of excess sludge to the methane fermentation process is a limiting factor for the rate of reaction occurring in the subsequent stages of the process. The kinetics of biochemical changes during spontaneous methane fermentation phases is directly influenced by the increase in the concentration of dissolved organic substances available to microorganisms in the process. Excess sludge deposition by different disintegration methods, ie: chemical, physical, combined increases the efficiency of the methane fermentation process. Among the modifications mentioned above, the advantages of physical methods, especially of thermal nature, should be emphasized. In addition to the significant modification of the excess sludge structure, it does not cause secondary contamination of the prepared sludge and therefore is a promising technological solution. The aim of the study was to determine the effect of dry ice disintegration on the susceptibility of excess sludge to biodegradation. Volatile fatty acids are an important intermediate product in methane fermentation and increased effects of the stabilization process is conditioned by their concentration. Since the phase limiting process is the hydrolysis phase, the first stage of the fermentation, the detailed analysis was carried out in the first eight days of the process by performing physicochemical determinations of the modified sludge. Periodic fermentation was carried out under mesophilic conditions. Excess sludge was prepared with dry ice in a volume ratio of dry ice to excess sludge in range from 0.05L-1 to 0.75L-1. Confirmation of the increased susceptibility of the prepared excess sludge to the methane fermentation process was a modification of the sludge structure expressed by the increase of the disintegration degree. For sludge subjected to disintegration with dry ice, using the most preferred reagent dose, in the following days of the methane fermentation process, in relation to methane fermentation of non-prepared excess sludge, increase of SCOD and TOC values as well as VFAs concentration was noted.
Specyficzna podatność osadów nadmiernych na proces fermentacji metanowej jest czynnikiem ograniczającym szybkość reakcji zachodzących w kolejnych etapach procesu. Na kinetykę przemian biochemicznych podczas zachodzących samorzutnie faz fermentacji metanowej wpływa bezpośrednio wzrost stężenia rozpuszczonych substancji organicznych dostępnych dla mikroorganizmów procesu. Modyfikacja osadów nadmiernych odmiennymi metodami dezintegracji, tj. chemicznymi, fizycznymi, hybrydowymi zwiększa efektywność procesu fermentacji metanowej. Spośród wymienionych powyżej metod modyfikacji należy podkreślić zalety metod fizycznych, zwłaszcza termicznych. Oprócz istotnej modyfikacji struktury osadów nadmiernych, nie powodują one wtórnego zanieczyszczenia preparowanych osadów i stanowią obiecujące rozwiązanie technologiczne. Celem przeprowadzonych badań było określenie wpływu dezintegracji osadów nadmiernych suchym lodem na wzrost podatność na biodegradację. Lotne kwasy tłuszczowe są ważnym produktem pośrednim fermentacji metanu, a zwiększona wydajność procesu stabilizacji zależy od ich stężenia. Ponieważ procesem limitującym fermentacje metanową jest faza hydrolizy, pierwszy etap stabilizacji, dokonano analizy wybranych oznaczeń fizyczno-chemicznych w ciągu pierwszych ośmiu dób procesu fermentacji modyfikowanych osadów Okresową fermentację metanową prowadzono w warunkach mezofilowych. Stworzono mieszaniny suchego lodu i osadów nadmiernych w stosunku objętościowym reagenta do osadów w zakresie od 0,05/1 do 0,75/1. Potwierdzeniem zwiększonej podatności dezintegrowanych osadów nadmiernych na proces fermentacji metanowej był zachodzący proces lizy osadów nadmiernych wyrażony wzrostem stopnia dezintegracji. W przypadku osadów nadmiernych poddanych dezintegracji suchym lodem, przy użyciu najkorzystniejszej dawki reagenta, w kolejnych dobach procesu fermentacji metanowej, w odniesieniu do fermentacji metanowej niepreparowanych osadów nadmiernych, odnotowano wzrost wartości rozpuszczonego chemicznego zapotrzebowania na tlen (ChZT), ogólnego węgla organicznego (OWO) oraz stężenia lotnych kwasów tłuszczowych (LKT).
Źródło:
Rocznik Ochrona Środowiska; 2018, Tom 20, cz. 1; 558-573
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Indirect Electrochemical Oxidation with Multi Carbon Electrodes for Restaurant Wastewater Treatment
Autorzy:
Sastrawidana, I. D. K.
Sukarta, I. N.
Powiązania:
https://bibliotekanauki.pl/articles/123822.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
chemical oxygen demand
electrochemical oxidation
multi carbon electrodes
removal efficiency
restaurant wastewater
Opis:
The removal of organic matter from the restaurant wastewater was investigated using the electrochemical oxidation method with multi carbon electrodes in a parallel construction. The degradation process was monitored by the measurement of COD concentration as a function of electrolysis time. The effect of operating parameter conditions on COD removal were investigated including initial pH, distance between electrodes, and the applied voltage difference. The results showed that the treatment of restaurant wastewater containing 2 g/L chloride ion using the electrochemical oxidation technique at the operation conditions characterized by: pH 5, distance between electrode of 10 cm and applied voltage of 12 V, enabled to obtained COD removal of 92.84% within 90 min electrolysis time. It is can be concluded that the indirect electrochemical oxidation method with multi carbon electrodes can be used effectively as an alternative technology for reducing COD and may be potentially applied for removal organic pollutants from wastewater at the industrial scale.
Źródło:
Journal of Ecological Engineering; 2018, 19, 1; 200-204
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Predictive Modelling for Characterisation of Organics in Pit Latrine Sludge from Unplanned Settlements in Cities of Malawi
Autorzy:
Kalulu, K.
Thole, B.
Mkandawire, T.
Kululanga, G.
Powiązania:
https://bibliotekanauki.pl/articles/124540.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
Akaike Information Criterion
biochemical oxygen demand
chemical oxygen demand
faecal sludge characteristics
multiple linear regression model
Opis:
The limited availability of data on faecal sludge characteristics remains one of the major challenges faced by developing countries in proper management of faecal sludge. In view of the limited financial resources and expertise in these developing countries, there is a need to come up with less-resource-intensive approaches for faecal sludge characterisation. Despite being used substantially in wastewater, there is limited evidence on the use of predictive modelling as a tool for cost-effective characterisation of faecal sludge. In this study, first order multiple linear regression modelling is investigated as a less-resource-intensive approach for accurate prediction of organics (biochemical oxygen demand and chemical oxygen demand) in pit latrine sludge. The predictor variables explored in the modelling include pH, electrical conductivity, total solids, total volatile solids, fixed solids and moisture content. The modelling uses data collected from 80 latrines in unplanned settlements of four cities in Malawi. The study shows that it is possible to reliably predict chemical oxygen demand and biochemical oxygen demand in pit latrine sludge using electrical conductivity and total solids, which require low levels of resources and expertise to determine.
Źródło:
Journal of Ecological Engineering; 2018, 19, 3; 141-145
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Textile dye removal using experimental wetland ponds planted with common duckweed under semi-natural conditions
Autorzy:
Yaseen, D. A.
Scholz, M.
Powiązania:
https://bibliotekanauki.pl/articles/207752.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
waste water treatment
Lemna-minor L
wetlands
chemical oxygen demand removals
natural conditions
oczyszczanie ścieków
mokradała
chemiczne usuwanie tlenu
barwnik
warunki naturalne
Opis:
The study assesses the performance of experimental wetland pond systems vegetated by Lemna minor L. (common duckweed or lesser duckweed) for textile azo dye removal. The objectives are to assess the influence of L. minor on water quality parameters, compare the dye and chemical oxygen demand (COD) removal of four dyes (Acid Blue 113, Reactive Blue 198, Direct Orange 46 and Basic Red 46) with each other, and monitor the effect of dye accumulation as a function of the relative growth rate (RGR) of L. minor. Findings indicate that the simulated shallow pond systems remove BR46 (low concentration) significantly (p < 0.05) higher than other dyes, and the ponds containing L. minor outperformed control ponds by around 51% in mean removal efficiency with a potential of L. minor for phytoremediation of approximately 13% efficiency.
Źródło:
Environment Protection Engineering; 2017, 43, 3; 39-60
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Carbonaceous materials in petrochemical wastewater before and after treatment in an aerated submerged fixed-bed biofilm reactor
Autorzy:
Trojanowicz, K.
Wojcik, W.
Powiązania:
https://bibliotekanauki.pl/articles/185052.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Chemical Oxygen Demand fractions
petrochemical wastewater
biofilm reactor
zapotrzebowanie tlenu
petrochemiczne ścieki
reaktor
Opis:
Results of the studies for determining fractions of organic contaminants in a pretreated petrochemical wastewater flowing into a pilot Aerated Submerged Fixed-Bed Biofilm Reactor (ASFBBR) are presented and discussed. The method of chemical oxygen demand (COD) fractionation consisted of physical tests and biological assays. It was found that the main part of the total COD in the petrochemical, pretreated wastewater was soluble organic substance with average value of 57.6%. The fractions of particulate and colloidal organic matter were found to be 31.8% and 10.6%, respectively. About 40% of COD in the influent was determined as readily biodegradable COD. The inert fraction of the soluble organic matter in the petrochemical wastewater constituted about 60% of the influent colloidal and soluble COD. Determination of degree of hydrolysis (DH) of the colloidal fraction of COD was also included in the paper. The estimated value of DH was about 62%. Values of the assayed COD fractions were compared with the same parameters obtained for municipal wastewater by other authors.
Źródło:
Chemical and Process Engineering; 2016, 37, 3; 373-382
0208-6425
2300-1925
Pojawia się w:
Chemical and Process Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł

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