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1

Zanieczyszczenia w wodzie i ściekach : źródła, toksyczność i innowacyjne podejścia do ich usuwania

Koronkiewicz Kamila, Kalinowska Monika, Świderski Grzegorz, Zawadzka Małgorzata, Çalik Fatma Defne, Yildiz Güray, Piekut Jolanta

Przemysł Chemiczny

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2025

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T. 104, nr 2

291--298.

PL

Rozwój technologii i nauki prowadzi do coraz to nowych odkryć, dotyczących m.in. tworzenia innowacyjnych materiałów i metod. Ich zastosowanie powoduje również wystąpienie nowych zanieczyszczeń poprodukcyjnych, a tego rodzaju zanieczyszczenia nazywane są nowo pojawiającymi się zanieczyszczeniami EC (emerging contaminants). Występowanie w środowisku i losy substancji, takich jak środki higieny osobistej, farmaceutyki, związki zaburzające gospodarkę hormonalną, pestycydy, nanomateriały, środki zmniejszające palność i produkty ich rozkładu, a także jony metali pochodzące z górnictwa, hutnictwa i przemysłu chemicznego, było coraz częściej omawianym zagadnieniem w ciągu ostatniej dekady. Celem pracy było przedstawienie najważniejszych, obecnie pojawiających się w środowisku zanieczyszczeń i omówienie metod usuwania ich z wody i ścieków.

EN

A review, with 28 refs., of the currently most significant emerging contaminants in surface water and wastewater. The environmental occurrence and fate of substances such as personal care products, pharmaceuticals, endocrine disrupting compounds, pesticides, nanomaterials, flame retardants and their decompn. products, as well as metal ions from mining, metallurgy and chem. industry were discussed. Innovative materials designed to improve the performance of current wastewater treatment techniques such as cyclodextrin polymers, organometallic structures and also advanced oxidn. processes were presented.

2

Stimulation of activated sludge biomass using artificial visible light

Yas Emad Ahmad, Aldoury Muzher Mahdi Ibrahem

Journal of Ecological Engineering

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2025

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Vol. 26, nr 4

123--135

EN

Visible light is a potential innovative method for developing the activated sludge (AS) system. AS is consisted of a complex community of diverse microbes that respond differently to light based on wavelength, intensity, and exposure time. The present study examined the possibility of stimulating activated sludge using visible light radiation. Five light wavelengths (white, solar, red, blue, and green lights) are provided with three intensity levels. Mixed liquor suspended solid (MLSS) and mixed liquor volatile suspended solid (MLVSS) were used as indicators to evaluate activated sludge performance. From the experimental results, 15–20 days achieved high biomass productivity for all wavelengths. There was a direct relationship between AS biomass and intensity, except white light, the proportion was inverse. Green, blue, and red light achieved maximum stimulation of MLSS reached (48.57, 48.29, and 33.57%) relative to control at (130±3.41, 100±2.9, and 40±4.89 W m-2). Besides, the highest stimulation of MLVSS under green, white, and solar light was (84.54, 55.01, 39.33%) relative to control at (115±3.17, 24±3.72, 40±3.1 W m-2). The maximum growth rate (μ) of MLSS and MLVSS achieved under white and green lights reached (0.096235, and 0.115377 d-1) at (24±3.72, 115±3.17 W m-2), during 5 days, respectively. Van and the developed models could predict a high correlation exceeding (r = 0.98) with white and solar light.

3

Packed bed reactor for efficient dye removal using ozone and hydrogen peroxide

Yousif Ban Muthanna, Abdulmajeed Yossor R.

Journal of Ecological Engineering

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2025

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Vol. 26, nr 2

327--341

EN

This study aimed to investigate the degradation of Congo red and Rhodamine B dyes in synthetic wastewater by ozonation and study the parameters that influence the efficiencies of color removal such as concentration of pollutants, gas flow rate, time of reaction, and the pH of solution. Congo red dye and Rhodamine B dye were selected as model pollutants. ozonation process of these dyes was carried out in a continuous reactor with a diameter of 8 cm and length of 25 cm. It was observed that over 85% of Congo red and 95% of Rhodamine B could be removed at 90 min for both dyes. and when using the H2O2 (0.5, 1, 1.5) ml for Rhodamine B and Cong Red at 90 min the decolorization efficiency in natural pH was 93%, 95%, 96%, 84%, 89%, and 94% respectively. When used the packing the decolorization efficiency changed from 77% to 82% for Rhodamine B and from 53% to 63% for Congo Red. Higher color removal could be achieved when ozonation was carried out in an alkaline condition (pH 10) for Congo Red and an acidic condition (pH 1.5) for Rhodamine B. The ozonation of dyes was dominant at room temperature and atmospheric pressure.

4

Utilization of metallurgical dust for the adsorptive removal of the organic pollutant Reactive Red 198

Pająk Magdalena

Archives of Environmental Protection

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2025

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Vol. 51, no. 4

66--77

EN

The global demand for effective and sustainable water treatment technologies has intensified due to growing water scarcity and industrial pollution. Accordingly, this study evaluated the potential of unmodified metallurgical dust, a by-product of the steel industry rich in metal oxides, as a low-cost adsorbent for removing Reactive Red 198 (a representative anionic azo dye) from both synthetic aqueous solutions and real textile wastewater. This research contributes to the the development of sustainable water treatment technologies by exploring waste valorization as a strategy for pollutant removal. Batch adsorption experiments were conducted using varying concentrations of Reactive Red 198 and different doses of metallurgical dust. Both synthetic dye solutions and actual textile wastewater were tested. Adsorption performance was evaluated using nonlinear isotherm models (Langmuir, Freundlich, and Dubinin-Radushkevich) and kinetic models (Lagergren Pseudo-First-Order, Pseudo-Second-Order, and Elovich) to better understand the adsorption mechanism. The adsorption data best fitted the Freundlich and Elovich models, indicating surface heterogeneity and a chemisorption-dominated process. The maximum experimental adsorption capacity was 49.42 mg·g-1 at an adsorbent dose of 0.5 g. The material maintained high performance even under real wastewater conditions, which were characterized by elevated pH and salinity, suggesting its resilience in complex matrices. Unmodified metallurgical dust exhibits strong potential as an effective, low-cost adsorbent for anionic dye removal. Its robust performance in real wastewater underscores its practical applicability and supports the integration of environmental waste management with water pollution mitigation.

PL

Globalne zapotrzebowanie na skuteczne i zrównoważone technologie oczyszczania wody nasila się w związku z narastającym problemem deficytu zasobów wodnych oraz postępującym zanieczyszczeniem środowiska przemysłowego. W związku z tym w niniejszym badaniu oceniono potencjał niemodyfikowanego pyłu metalurgicznego – ubocznego produktu przemysłu stalowego, bogatego w tlenki metali – jako niskokosztowego adsorbentu do usuwania barwnika reaktywnego czerwieni 198, reprezentatywnego anionowego barwnika azowego, zarówno z syntetycznych roztworów wodnych, jak i z rzeczywistych ścieków tekstylnych. Badania te wpisują się w rozwój zrównoważonych technologii oczyszczania wody poprzez wykorzystanie odpadów przemysłowych jako strategii redukcji zanieczyszczeń. Eksperymenty adsorpcyjne prowadzono w układzie okresowym, stosując różne stężenia barwnika oraz zróżnicowane dawki pyłu metalurgicznego. Testowano zarówno roztwory modelowe, jak i rzeczywiste ścieki z przemysłu tekstylnego. Skuteczność adsorpcji oceniano przy użyciu nieliniowych modeli izoterm (Langmuira, Freundlicha oraz Dubinina-Raduszkiewicza) oraz modeli kinetycznych (pseudopierwszorzędowego Lagergrena, pseudo-drugorzędowego i Elovicha), aby lepiej zrozumieć mechanizm procesu. Dane doświadczalne najlepiej dopasowały się do modeli Freundlicha i Elovicha, wskazując na heterogeniczność powierzchni oraz dominującą rolę chemisorpcji. Maksymalna pojemność adsorpcyjna wyniosła 49,42 mg·g⁻¹ przy dawce adsorbentu 0,5 g. Materiał zachował wysoką skuteczność również w warunkach rzeczywistych ścieków, charakteryzujących się podwyższonym pH i wysokim zasoleniem, co potwierdza jego odporność w złożonych matrycach. Niemodyfikowany pył metalurgiczny wykazuje duży potencjał jako skuteczny i tani adsorbent do usuwania barwników anionowych. Jego stabilna efektywność w rzeczywistych ściekach podkreśla praktyczną przydatność materiału i wspiera koncepcję łączenia gospodarki odpadami przemysłowymi z działaniami na rzecz ograniczania zanieczyszczenia wód.

5

Fruit and vegetable waste management through co-digestion with local market wastewater: operating conditions and system kinetics

Mkhize Nqobile, Khumalo Siphesihle Mangena, Tetteh Emmanuel Kweinor, Rathilal Sudesh

Agricultural Engineering

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2025

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Vol. 29, No. 1

114--134

EN

Environmental pollution from fruit and vegetable waste (FVW) produced by local markets in South Africa is inevitable. Nevertheless, the current management strategy of disposing of FVWs in landfills contributes to the emission of greenhouse gases. Therefore, valorizing agricultural waste into bioenergy is critical for achieving zero waste and reducing the carbon footprint. In this study, parametric optimization of the co-digestion of FVWs with market wastewater (MW) was conducted using the Box-Behnken design (BBD) adapted from response surface methodology (RSM). The study identified optimal combinations of process variables, i.e., temperature, pH, hydraulic retention time (HRT), and organic loading rate (OLR), to produce biogas while reducing volatile solids (VS) and chemical oxygen demand (COD) from wastewater. At optimal operating conditions of 40°C, HRT of 10 days, pH of 7.2, and an OLR of 3.98 kg VS·m-3·day-1 , a desirability of 100% was achieved. A biogas production rate of 717 mL·day-1 was reported, with VS and COD removals of 73.37% and 79.24%, respectively. The robustness of the predictive models developed using RSM was corroborated by R2 values greater than 0.9 for all output variables. The Modified Gompertz model was well-fitted to the experimental data, yielding an R2 of 0.995 and a lower root mean square error (RMSE) of 21.08. The findings of the present study suggest that the valorization of FVW through co-digestion with wastewater can be considered a promising, environmentally sustainable technology for agro-waste management and bioenergy production.

PL

Zanieczyszczenie środowiska odpadami z owoców i warzyw powstających na lokalnych targowiskach w Republice Południowej Afryki jest nieuniknione. Co więcej, obecna strategia utylizacji tego rodzaju odpadów przyczynia się do emisji gazów cieplarnianych. Dlatego wykorzystanie odpadów rolniczych do produkcji bioenergii ma kluczowe znaczenie dla osiągnięcia celu „zero odpadów” i zmniejszenia śladu węglowego. W tym badaniu przeprowadzono parametryczną optymalizację kofermentacji odpadów ze ściekami komunalnymi przy użyciu modelu Boxa-Behnkena, zaadaptowanego z metodologii powierzchni odpowiedzi (RSM). W badaniu ustalono optymalne kombinacje zmiennych procesowych, tj. temperatury, pH, hydraulicznego czasu retencji i wskaźnika obciążenia organicznego do produkcji biogazu przy jednoczesnym zmniejszeniu lotnych ciał stałych i chemicznego zapotrzebowania na tlen ze ścieków. W optymalnych warunkach pracy, przy temperaturze 40℃, czasie retencji 10 dni, pH 7,2 i zapotrzebowaniu na tlen rzędu 3,98 kg VS·m-3 dzień-1, uzyskano pożądaną wydajność 100%. Odnotowano wskaźnik produkcji biogazu na poziomie 717 ml·dzień-1 przy czym poziom redukcji lotnych ciał stałych i chemicznego zapotrzebowania na tle wyniosło odpowiednio 73,37% i 79,24%. Solidność modeli predykcyjnych opracowanych przy użyciu RSM została potwierdzona wartościami R2 większymi niż 0,9 dla wszystkich zmiennych wyjściowych. Zmodyfikowany model Gompertza był dobrze dopasowany do danych eksperymentalnych, dając R2 na poziomie 0,995 i niższy średni błąd kwadratowy (RMSE) wynoszący 21,08. Wyniki niniejszego badania pokazują, że zagospodarowanie odpadów z owoców i warzyw poprzez kofermentację ze ściekami można uważać za obiecującą, zrównoważoną środowiskowo technologię zarządzania odpadami rolniczymi i produkcji bioenergii.

6

Infiltracja i wody przypadkowe w systemach kanalizacyjnych

Mioduszewska Sylwia, Miszta-Kruk Katarzyna

Technologia Wody

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2024

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Nr 1 (83)

20-23

PL

W systemach kanalizacyjnych szeroko pojętych, w ostatnich latach zachodzą istotne zmiany. Na rynku pojawiają się nowe produkty, narzędzia i rozwiązania do lepszego sterowania, monitorowania i zarządzania pracą tych układów. Tym samym systemy kanalizacyjne stają się bardziej skomplikowane, a ich poszczególne elementy, nie zawsze są dobrze ze sobą dobrane, Mimo, że obecnie są to zaawansowane układy, problemy i zdarzenia niepożądane nadal występują. Jednym ze zjawisk mających znaczący wpływ na poprawne funkcjonowanie systemów kanalizacyjnych jest zjawisko występowania infiltracji i wód przypadkowych. Problem jest o tyle istotny, że w zależności od różnych źródeł, ze względu na infiltrację ilość ścieków dopływających do oczyszczalni zwiększa się od 2% do nawet 75% zależnie od warunków.

EN

Sewerage systems, broadly defined, have been undergoing significant changes in recent years. New products, tools, and Solutions are appearing on the market to control, monitor, and manage the operation of these systems better. Thus, sewerage systems are becoming more complex, and their components are only sometimes well-matched with each other. Even though they are now advanced systems, problems and adverse events still occur. One of the phenomena that significantly impacts the proper functioning of sewerage systems is the occurrence of infiltration and incidental water. The problem is essential in that, depending on the various sources, due to infiltration, the volume of wastewater flowing into the treatment plant increases from a flowing into the sewage treatment plant rises from 2% to as much as 75%, depending on the conditions.

7

A Brief Overview of Antibiotic Contamination Sources in Wastewater and Elimination Approaches

Mumtaj Zeba Ali, Khan Abdul Rahman, Ansari Jamal Akhtar, Asiri Abdullah, Khan Saimah

Rocznik Ochrona Środowiska

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2024

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Tom 26

201--216

EN

Antibiotic contamination of natural resources and the receiving environment is of great concern. This brief discussion consists of the sources regarding antibiotic contamination and the analysis of several viable methods of removing antibiotic substances. The sources include domestic discharges, agricultural runoff, and pharmaceutical manufacturing effluents. Antibiotics are classified as emerging contaminants attributed to their persistence in the environment. Antibiotics and their metabolites enter the environment through human and animal urine and faeces. Persistent pollutants are introduced to aquatic ecosystems as they pass the wastewater treatment process. The overuse of antibiotics has led to the emergence of bacteria and genes resistant to antibiotics in the environment. This study provides a descriptive overview of antibiotic sources in the environment, their harmful effects, analytical techniques for its detection in wastewater, related challenges in monitoring antibiotic contamination in water, and recently used techniques for its removal from wastewater and problems associated with current strategies. The study also underscores the importance of understanding the sources and learning how to successfully apply methods to minimise the effects of antibiotic contamination in wastewater.

8

Study on removal of pollutants from wastewater by using the big data technology

Yongxian Liu

Przemysł Chemiczny

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2024

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T. 103, nr 12

1427--1432

EN

The pollutants (total org. C) removal from papermaking wastewater was studied in a continuous-flow Hastelloy alloy reactor (10 mL) under max. 40 MPa at max. 600°C in presence of TiO₂-Al₂O₃ catalyst after addn. of H₂O₂ (1000-4000 mg/L) for 1-4 min. The flow rates of the oxidant and wastewater streams were 1-5 mL/min. After cooling purified wastewater to the room temp., the precipitate formed was sepd. by filtration. The pollutants removal efficiency reached 94.29%. Use of big data technol. for controlling the process resulted in an increase of the removal efficiency up to over 98%.

PL

Usuwanie zanieczyszczeń (całkowitego węgla organicznego) ze ścieków papierniczych badano w reaktorze (10 mL) ze stopu Hastelloy pod ciśnieniem maks. 40 MPa w temp. maks. 600°C w obecności katalizatora TiO₂-Al₂O₃ po dodaniu H₂O₂ (1000-4000 mg/L) przez 1-4 min. Natężenia przepływu utleniacza i ścieków wynosiły 1-5 mL/min. Po schłodzeniu oczyszczonych ścieków do temperatury pokojowej powstały osad oddzielono przez filtrację. Skuteczność usuwania zanieczyszczeń osiągnęła 94,29%. Zastosowanie technologii big data do sterowania procesem spowodowało wzrost stopnia usunięcia do ponad 98%.

9

Skuteczność zeolitu naturalnego w usuwaniu wybranych zanieczyszczeń ze ścieków z przemysłu drobiarskiego

Makara Agnieszka, Łopata Karolina, Kowalski Zygmunt, Generowicz Agnieszka, Mala Marcin

Przemysł Chemiczny

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2024

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T. 103, nr 10

1128--1132

PL

Przedstawiono wyniki badań oczyszczania ścieków z przemysłu drobiarskiego za pomocą zeolitu naturalnego typu klinoptylolitu pochodzącego z Turcji. Proces oczyszczania prowadzono przy zmiennych dawkach zeolitu, w zakresie 1-5% mas. (w stosunku do masy oczyszczanego ścieku) oraz przy stałym czasie mieszania wynoszącym 30 min. Zastosowany zeolit naturalny wraz ze wzrostem dawki wykazywał coraz większą skuteczność w obniżaniu oznaczanych parametrów. Przy najwyższej dawce 5% mas. umożliwił obniżenie ChZT i azotu Kjeldahla o odpowiednio ok. 82% i 76%, całkowicie obniżył mętność oraz zredukował barwę oczyszczanego ścieku o ok. 92%. Stwierdzono, że przy dawkach wynoszących 4 i 5% występuje wyraźne zmniejszenie emisji substancji zapachowych znad oczyszczonych próbek ścieków.

EN

Poultry industry wastewater was mixed with natural zeolite of clinoptilolite type from Turkey, at room temp. for 30 min and then filtered. The effect of variable zeolite doses (1-5% by mass) on parameters such as COD, Kjeldahl N concn., Ca, Fe, Pb, Zn, Mn, Cd, Ni content, color, turbidity, pH and perceptible odor impressions from treated wastewater samples was detd. The zeolite used showed greater effectiveness in reducing the parameters detd. with increasing dose. At the highest dose (5% by mass), it reduced COD and Kjeldahl N by about 82% and 76%, completely reduced turbidity (100%) and reduced the color of treated wastewater by about 92%. At doses of 4% and 5%, a significant reduction in odorous substances emission from treated wastewater samples was observed.

10

Skuteczność koagulantów w usuwaniu wybranych zanieczyszczeń mikrobiologicznych i fizykochemicznych ze ścieków z przemysłu owocowo-warzywnego

Makara Agnieszka, Kmiecik Dominika, Kowalski Zygmunt

Przemysł Chemiczny

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2024

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T. 103, nr 7

799--804

PL

Przedstawiono wyniki badań oczyszczania ścieków z przemysłu owocowo-warzywnego metodą koagulacji, za pomocą zmiennych dawek koagulantów: glinowego PAX 18 i żelazowego PIX 113 (2–10 mL/L), oraz neutralizacji 10-proc. roztworem mleka wapiennego. Koagulant glinowy PAX 18 był bardziej skuteczny w usuwaniu zanieczyszczeń mikrobiologicznych. W oczyszczonych frakcjach ciekłych w całym zakresie stosowanych dawek nie stwierdzono obecności enterokoków i bakterii Escherichia coli, a ogólna liczba mikroorganizmów została obniżona o ponad 99%. Wartość ChZT została maksymalnie obniżona o 67% za pomocą koagulantu glinowego (dawka 2 mL/L) oraz o 72% za pomocą koagulantu żelazowego (dawka 6 mL/L). Barwę oczyszczonych ścieków obniżono o 88–97%, a mętność niemalże całkowicie (< 1 NTU).

EN

Wastewater from the fruit and vegetable industry was treated by coagulation, using variable doses of Al PAX 18 and Fe PIX 113 coagulants (2–10 mL/L) and neutralized with a 10% soln. of lime milk. The PAX 18 was more effective in removing microbiol. contaminants in the entire range of doses used. No enterococci or Escherichia coli were detected, and the total no. of microorganisms was reduced by more than 99%. The COD value was reduced by a max. of 67% using an Al coagulant (dose 2 mL/L) and by 72% using an Fe coagulant (dose 6 mL/L). The color of the treated sewage was reduced from 88 to 97%, and the turbidity was almost completely reduced (< 1 NTU).

11

The influence of winter road maintenance on the presence of chlorides in wastewater entering small treatment plants

Kaczor Grzegorz B., Cupak Agnieszka, Karczmarczyk Agnieszka

Journal of Water and Land Development

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2024

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no. 63

184--190

EN

During the appearance of the first snowfall, there is a revival of discussion on effective methods of protecting road surfaces and sidewalks against icing. In Poland and many other countries, so-called road salt, mainly sodium chloride (NaCl) with additives, is often used to lower the melting point of snow and ice. Using chemicals to protect road surfaces brings many negative side effects reported in the literature. Less frequently published research results indicate, and also alarm, that increased chloride concentrations can appear in wastewater flowing into sanitary (separate) sewers. In the case of small wastewater treatment plants, increased chloride concentrations can have a negative impact primarily on the biological processes of wastewater treatment and, after discharge from the wastewater treatment plant, on the biological life in the waters and the nearest recipient environment of the treated wastewater. The study aimed to determine the concentrations and loads of chlorides in wastewater flowing through the distribution sewer system to 4 small wastewater treatment plants located in Poland, in the Lesser Poland Province, during snowmelt and heavy rainfall in 2019-2023. The study showed a significant increase in concentrations and loads of chlorides in wastewater in February. Unit chloride load in raw sewage during snowmelt varied from 7 to 12 kg∙d-1 per 1 km length of separate sewer network. There was also a repeated, but much lower, increase in chloride concentrations during summer and autumn precipitation. This is when the leaching of residual salt accumulated around the road surface occurred.

12

Utilization of WWTP Output into Liquid Organic Fertilizer on the Growth of Pak Choi (Brassica rapa L.)

Afifah Ratih Nur, Setyono Prabang, Rachmawati Siti

Journal of Ecological Engineering

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2024

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Vol. 25, nr 10

76--90

EN

Industrial wastewater generally contains many nutrients and organic materials that can be useful as a source of nutrition for plants. Processing wastewater into liquid organic fertilizer (LOF) can be a solution to manage industrial wastewater produced and can reduce the negative environmental impact of direct discharge into the environment. This study aims to determine the effect and optimal concentration of LOF from WWTP output of PT X on pak choi (Brassica rapa L.) plant growth and analyze the quality of LOF content according to SNI in the Minister of Agriculture Regulation Number 70 of 2011. This study used the complete randomized design (CRD) method, with the following treatment combinations: A (control, 100% WWTP output of PT X), B (20% LOF), C (40% LOF), D (60% LOF), E (80% LOF), F (100% LOF). Each treatment was repeated three times so that 18 test plants were obtained. Observation variables include height, number of leaves, leaf width, and fresh weight of Brassica rapa L. plants. Data analysis using SPSS one-way analysis of variance (ANOVA) test and continued to DMRT test. The results showed that the provision of LOF from WWTP output of PT X had a significant effect on the growth of Brassica rapa plants in the parameters of plant height in the fourth and fifth weeks, the number of leaves from the second to the fifth week, the leaf width parameter in the fifth week, and the fresh weight parameter. The optimal treatment for the LOF comparison of all parameters is in treatment D (60% LOF). The test results of LOF content contain C-organic 3.61%, nitrogen 1.1%, phosphate 0.385%, potassium 0.485%, and pH 5.27. These values have not met the SNI LOF in the Minister of Agriculture Number 70 Regulation of 2011. There is a need for the addition of organic ingredients that can increase the N, P, and K content in order to increase the POC yields and have a higher impact on plants.

13

Treatment of Wastewater from Oil Refineries by a Combination of Electrocoagulation with Photocatalytic Processes Using Immobilized Nano-Zinc Oxide Photocatalyst

Hameed Qasem Kadhum, Mohammed Wadood Taher

Journal of Ecological Engineering

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2024

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Vol. 25, nr 11

109--123

EN

The present work aimed to reduce the COD of petroleum refinery wastewater using individual and combined processes based on the electrocoagulation and photocatalytic process with immobilized nano-zinc oxide. Also, energy savings alongside performance improvements were evaluated within this conglomerated system. Results showed that the removal efficiency of COD was 72% after 120 min when using electrocoagulation process under the given conditions (15 mA/cm2, pH of 7, and flow rate of 0.5 L/min). Regarding the process involving photocatalysis, the removal efficiency of COD was 76% after 120 min under the analyzed conditions (ZnO concentration of 80 g/m2, pH of 7, power of irradiation equal to 65 W, and flow rate of 0.5 L/min). Several combined sequential and simultaneous systems were tested. Results confirmed that the simultaneous photo-EC system operated at 30 min is the best one and has the ability to achieve COD removal of 82% under the studied conditions (15 mA/cm2, pH of 7, and flow rate of 0.5 L/ min, ZnO concentration of 80 g/m2, and 65 W). Furthermore, the further notable features of the combined simultaneous photo-EC system were operating at shorter operation time and lowering dissolution rate of anode electrode (0.2 gram) that makes the system to be the most economic process with an energy consumption of 28.44 kWh/kg COD.

14

Treatment of Petroleum Refinery Wastewater by Activated Carbon Assisted Electrocoagulation Process

Atiyah Zainab Y., Muallah Shatha K., Sabbar Huda A., Abbar Ali H.

Journal of Ecological Engineering

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2024

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Vol. 25, nr 10

239--251

EN

The removal of COD from wastewater generated by petroleum refinery has been investigated by adopting electrocoagulation (EC) combined with adsorption using activated carbon (AC) derived from avocado seeds. The process variables influencing COD removal were studied: current density (2–10 mA/cm2), pH (4–9), and AC dosage (0.2–1 g/L). Response surface methodology (RSM) based on Box–Behnken design (BBD) was used to construct a mathematical model of the EC/AC process. Results showed that current density has the major effect on the COD removal with a percent of contribution 32.78% followed by pH while AC dosage has not a remarkable effect due to the good characteristics of AC derived from avocado seeds. Increasing current density gives better results while neutral conditions are suitable for EC/AC. The optimized conditions for higher removal of COD adopting the combined process were a current density of 10 mA/cm2, AC dosage of 0.2 g/L, and pH of 6.8 in which a removal efficiency of 81.6% was attained. The combining of EC with adsorption showed that adding a suitable amount of AC derived from avocado seeds resulted in enhancement of COD removal from 63.45% to 81.4%. Based on this high removal efficiency, the EC/AC could be adopted instead of traditional EC.

15

The Use of Biofilter in Anaerobic Baffled Reactor to Improve Quality of Methane Concentration and Effluent as Liquid Organic Fertiliser

Ningsih Lydia Mawar, Hasanudin Udin, Roubík Hynek

Journal of Ecological Engineering

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2024

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Vol. 25, nr 9

226--234

EN

The biofilter used is a simple technology in anaerobic digestion to remove pollutants from the substrate to enhance biogas production and nutrient effluent, which can be used as liquid organic fertiliser. This study aims to determine the effect of using a biofilter to improve biogas production and biogas effluent as an organic fertiliser material. The results show that the highest methane concentration is 60.64% at a dosage 200 L·day-1. The total solid (TS) content of biogas effluent exhibits a decrease of approximately 44% across all substrate doses, with respective percentages of TS of 0.16%, 0.03%, 0.025%, and 0.034% for 50 L·day-1, 100 L·day-1, 150 L·day-1, and 200 L·day-1, respectively. The use of biofilters in an ABR can significantly enhance the quality of biogas effluent, rendering it suitable for use as a liquid organic fertiliser. By capturing and biodegrading pollutants, the biofilter component can further enrich the nutrient content of the effluent, which already contains essential nutrients due to the anaerobic conditions and compartmentalised design of the ABR. The nutrient content in the biogas effluent mix with nutrition (AB mix) namely; N-total 262.5 mg·L-1, P-available 0.399 mg·L-1, Ca 4.08 mg·L-1, Mg 25.24 mg·L-1, Cu 0.032 mg·L-1, and Fe 13.09 mg·L-1 follows the standard organic fertiliser of the Minister of Agriculture of Indonesia.

16

Synthesis of Nano-Calcium Fluoride–Based Materials from Phosphogypsum Waste and their Use in Wastewater Treatment–Adsorption of Reactive Blue 21 Dyes

Bensemlali Meryem, Hatimi Badreddine, Mortadi Halima, Chajri Fatima-Zahra, Aarfane Abdellatif, Mohammed El Idrissi, Joudi Meryeme, Labjar Najoua, Nasrellah Hamid, Bakasse Mina

Journal of Ecological Engineering

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2024

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Vol. 25, nr 8

62--71

EN

A novel synthesis process and characterization of nano-calcium fluoride (n-CaF2) single crystal prepared from phosphogypsum waste. The phosphogypsum (CaSO4 2H2O) powder has been mechanically mixed with NH4F in presence of a controlled amount of water. The mixture still sintered for 48 hours until the formation of nano calcium fluoride particles. The n-CaF2 particles have been characterized by several techniques, The techniques utilized included X-ray diffraction (XRD), infrared spectroscopy (IR), and scanning electron microscopy (SEM). Therefore, it was confirmed that very pure n-CaF2 was obtained with a Ca/F ratio of 0.5 and an average crystalizing size measured according to the Debye-Scherrer equation of 11 nm. Based on the findings reached, The characterization data revealed successful synthesis of n-CaF2 from phosphogypsum. Additionally, the adsorption performance of the elaborated n-CaF2 was tested in Reactive Blue 21 (RB21) anionic dye removal, Adsorption tests were conducted in a batch reactor, focusing on key factors such as contact time, which can significantly influence the adsorption results. adsorption amount, pH, and dye concentration were tested. Hence results show an important adsorption performance of n-CaF2 with Reactive Blue 21 removal rate up to 90%.

17

Synthesis and Characterization of a Contemporary Type of Metal-Organic Framework and its Application for Purification Wastewater from Toxic Methylene Blue Dye

Attar Osama Jassim, Alrubaye Rana Th. A.

Journal of Ecological Engineering

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2024

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Vol. 25, nr 1

37--48

EN

This paper describes the synthesis of a promising material and evaluates the suitability of a metal-organic framework (MOF-199) for purifying toxic methylene blue (MB) dye wastewater via an adsorption process. (MOF-199) is considered much better than traditional adsorbents. The research focused on determining the adsorption characteristics and dye removal effectiveness with MOF-199, where several factors were studied, including dye concentration, contact time, amount of adsorbent, and pH. The highest observed dye removal efficiency was 97.21% when the pH was 7.5, and the reaction duration was 90 minutes. This was achieved by adding 0.2 g of MOF-199 to a dye solution containing 20 mg/L methylene blue. The adsorption process was evaluated by Langmuir, and the Freundlich isotherm models. As the strong correlation factor (R2 = 0.9989) indicates a pseudo-second-order kinetic model describes the adsorption methylene blue by MOF-199 the best. This indicates that the main mechanism of dye removal is chemisorption. Finally, the MOF-199 material can have remarkable reusability as an adsorption material for MB and subsequent efficiency of MOF-199 exhibited a reduction of 14.43% after undergoing four cycles, compared to its initial state. Yet, it remained at a commendably high level.

18

Standardizing the Wastewater Composition in Order to Minimize the Eutrophication Risk for the Reservoir

Proskurnin Oleg, Tsapko Natalia, Ivashchenko Taras, Vasilenko Sergey, Belokon Karina, Zakharchenko Nikolay, Yurchenko Anatolii, Teliura Natalia

Journal of Ecological Engineering

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2024

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Vol. 25, nr 6

144--152

EN

The article strives to determine the allowable content of nutrients in the wastewater that is being discharged into a reservoir, with the end goal of minimizing the risk of eutrophication. It was noted that the methodology currently used in Ukraine and most European countries to control pollutant discharge in wastewater is designed to simply not exceed the permissible pollution level in natural water based on sanitary indicators, which does not guarantee the absence of the eutrophication risk to the water bodies. The article describes a developed method for determining the allowable composition of wastewater based on biogenic indicators. The proposed method takes into account the consecutive transformation of nutrients, the probabilistic nature of the factors that determine the quality of water in water bodies, as well as the cost of purifying wastewater from various pollutants. The problem was considered for the case of wastewater discharge into a reservoir through a watercourse. This research is a practical scientific basis for further improving the methodology for standardization of the wastewater composition in order to protect water bodies from eutrophication.

19

Pollutant Removal in Wastewater from Anaerobic Digesters by Water Lettuce (Pistia stratiotes L.) at Both Still-Water and Running-Water Stages

Thuan Nguyen Cong, Khanh Huynh Cong, Van Cong Nguyen

Journal of Ecological Engineering

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2024

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Vol. 25, nr 6

80--89

EN

This research investigated the effectiveness of water lettuce (WL; Pistia stratiotes L.) in improving the quality of wastewater from biogas systems. Two treatments were designed, one without WL and the other with WL. First, WL were raised in containers that had 15 L of wastewater with an initial ammonium concentration of about 15 mg/L at the still-water stage (days 0–7). Then, at the running-water stage (days 10–22), wastewater with a targeted NH4+-N concentration of about 15 mg/L in a 5-L tank was gravitationally delivered continually into terraced Styrofoam containers designed as ponds 1, 2 and 3. Water samples were collected on days 0, 3, 7, 10, 13, 16, 19 and 22, and fresh weights of WL were measured on the same days of sampling the water. The results showed that at the still-water stage, WL contributed to the reduction of chemical oxygen demand (14.74±4.14% and 8.69±0.92%, respectively), total inorganic nitrogen (23.93±2.35% and 12.80±1.30%, respectively), ammonium (25.21±5.44% and 1.12±0.93%), nitrite (59.98±3.22% and 22.37±1.21%, respectively) and phosphate (71.84±0.89% and 61.64±1.65%, respectively) on days 0–3 more than on days 4–7 but did not help decrease nitrate concentrations on days 0–7. WL contributed to reducing organic matter less at the running-water stage than at the still-water stage. WL helped lower ammonium, nitrite and nitrate concentrations at the running-water stage more than at the still-water stage but did so more for ammonium and nitrate compared with nitrite at the running-water stage. No differences in pollutant concentration reductions between the two treatments (without and with WL) were found in ponds 1, 2 and 3. On days 10–22, no clear trend in increasing or decreasing pollutant concentrations emerged, except nitrite concentration, which lessened over time. No significant differences in the relative daily WL fresh biomass increase between the still-water and the running-water days were observed. The findings indicate that WL is an aquatic plant that can be used in treating wastewater from biogas systems, showing a high efficiency in lowering phosphorus concentrations and a potential for removing nitrite.

20

Optimum Conditions for Applying the Magnetic Absorption Methodfor Decontamination of Ferrous Sulphate and Chromate-Containing Wastewater

Radovenchyk Vyacheslav, Ivanenko Olena, Otrokh Olena, Overchenko Tetiana, Ivaniuta Serhii, Benatov Daniel, Frolenkova Svitlana, Hurieva Liudmyla

Journal of Ecological Engineering

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2024

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Vol. 25, nr 5

321--334

EN

The article deals with the acute issue of intensive contamination of surface and underground waters with iron and chromium ions, which reduces the amount of water suitable for consumption. It was noted that because of monitoring the state of transboundary rivers of Ukraine within the framework of bilateral agreements, an unacceptable excess of the content of heavy metal ions was recorded. The main polluters of the water environment are machinebuilding enterprises that discharge untreated or insufficiently treated metal-containing wastewater from the processes of steel etching, chrome plating, etc. Recently, the processing of these solutions to obtain a suspension of highly dispersed particles with magnetic properties–magnetite has been increasingly practiced. One of the directions of its use is the sorption of various pollutants in water environments, i.e., the application of the magnetic absorption method. Our study shows the advantages of using magnetite obtained from sulphate solutions in comparison with the traditional sulphate-chloride solution, the influence of the ratio of iron (II) and (III) ions, temperature, pH, nature of the precipitant, salinity on the dispersion of the obtained magnetic particles. When applying the magnetic absorption method, it was determined that hydrolyzed forms of iron (III) ions are best sorbed on magnetite, the removal process of which from aqueous solutions occurs quite intensively during the first two minutes. During the study of various samples of magnetite, it was established that in acidic solutions, with an increase in the ratio of iron (II) and (III) ions, the efficiency of iron ion removal decreases; in neutral and alkaline solutions, such a dependence is not observed. In the proposed technological scheme, purifying wastewater containing 10–100 mg/dm3 of iron ions is advisable by adding 100–1000 mg/dm3 of magnetite suspension and alkali solution to a pH of 8–9. The study showed that during the treatment of chromate-containing waters with magnetite, in addition to the processes of reduction of chromate ions, oxidation of surface Fe2+ ions to Fe3+, sorption of Cr3+ ions or Cr(OH)3 hydroxides, the reduction of chromate anions on its surface is observed, the basis of which may be the formation chemical compounds, as well as the sorption mechanism. The optimal conditions for removing chromium (VI) compounds from model solutions are to conduct the process at an elevated temperature and use magnetite with a 20 mg per 1 mg Cr6+ consumption.