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1

A Breakthrough Approach for Superior Cyanobacteria (Microcystis aeruginosa) Removal and Phosphorus Adsorption

Thongdamrongtham Somjate, Junsiri Supanee, Mongkol Nukul, Chaikhan Sitthichai

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 2

333--350

EN

This study examines the effectiveness of modified drinking water treatment residue (MDWTR) in removing Microcystis aeruginosa, as well as its collaborative action with poly aluminium chloride (PAC) for effective contaminant removal. In addition, the phosphorus adsorption capacities of MDWTR samples with differing particle sizes are evaluated. The results indicate that MDWTR alone has a positive effect on Microcystis aeruginosa removal, with S-type MDWTR(<90 μm) exhibiting the highest removal efficiency. Moreover, when combined with PAC, MDWTR’s removal efficiency is significantly enhanced, further validating its efficacy. The analysis of isotherms provides strong evidence for the substantial adsorption capacities of MDWTR samples, with various MDWTR types exhibiting distinct affinities. These results demonstrate MDWTR’s potential as adsorbent, Microcystis aeruginosa removing and emphasise its versatility in water treatment applications.

2

Improved Reduction of COD, BOD, TSS and Oil & Grease from Sugarcane Industry Effluent by Ferric Chloride and Polyaluminum Chloride Coupled with Polyvinyl Alcohol

Panhwar Aijaz, Bhutto Shahid

Ecological Engineering & Environmental Technology

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2021

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Vol. 22, iss. 2

8--14

EN

Rapid industrialization and urbanization severely affect our environment and water resources. Disposal of untreated wastewater to environment is a great threat to water bodies and environment. Sugarcane industry is an important industrial sector; globally it is also largest source of pollution of surface water and groundwater resources. It comprises a huge amount of chemicals and inorganic pollutants. Many treatment methods have been employed for the treatment of the sugarcane industry wastewater, such as chemical treatment, physical treatment, ion exchange, electrocoagulation and biological treatment. It is a fact that not a single treatment technique is effective for industrial effluent treatment. In this study, the physicochemical technique was used to remove the major pollutants as per Sindh Environmental Protection Agency (SEPA) effluent standards that include Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD), Total Suspended Solid (TSS) and Oil & Grease content. In these techniques e.g. chemical coagulation ferric chloride (FC) and poly aluminum chloride (PAC) coupled with polyvinyl alcohol (PVA), with different doses were used for achieving the optimum results. The best results were observed for COD, BOD, TSS and Oil & Grease reduction by FC and PAC dosing 180 mg/300 ml coupled with 45 mg/300 ml PVA. Further, it was also observed that the FC removal efficiency in slightly acidic to neutral medium (pH = 6–7) for COD (97.5%) and BOD (97.5%) is higher than PAC. However, PAC does perform well in slightly neutral to basic medium (pH = 7.5–8) than FC for the removal of Oil & Grease (95.3%) and TSS (97.4%) from the sugarcane effluent.

3

Electrical neutralization ability of polyaluminum chloride (PACl) coagulants with different OH–/Al3+ ratios by fluorescence quenching effect

Chi Fung Hwa, Cheng Wen Po, Yu Ruey Fang, Chen Zhao Feng

Environment Protection Engineering

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2020

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Vol. 46, nr 2

25--39

EN

The electrical neutralization ability of polyaluminum chlorides (PACls) with respect to humic acid was investigated by the fluorescence quenching method. The Stern–Volmer constant (Kq) at various pH and coagulation doses was determined for polyaluminum chlorides (PACl-B) of various basicities (B, B = [OH–]/[Al]). The experimental results show that under acidic conditions, the order of Kqvalues of PACl-B is PACl-2.5 > PACl-2.3 > PACl-1.5 > AlCl3. In solutions of pH = 7, the order of Kqvalues is PACl-1.5 > PACl-2.3 > PACl-2.5 > AlCl3. When pH > 7, aluminum ions are rapidly hydrolyzed, thus PACls of various basicities generally do not show capacity for electrical neutralization with humic acid. At pH = 6, all PACls-B obtain the maximum Kq values, indicating that humic acid and PACl-Bcoagulation process is less affected by H+ or OH– ions, and produces the best electrical neutralization ability. Compared to the past method of using surface potential as a means of determining the ability of neutralization of coagulation, the results of this study show that the Kq value of the quenching effect can reduce the experiment complexity.

4

Wpływ temperatury i pH na skuteczność usuwania zanieczyszczeń z wody podziemnej w procesie koagulacji

Krupińska I.

Ochrona Środowiska

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2015

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Vol. 37, nr 3

35--42

PL

Przedmiotem badań była woda podziemna z utworów czwartorzędowych o zwiększonej zawartości substancji organicznych, której oczyszczanie w układzie konwencjonalnym stwarza problemy technologiczne. Przeprowadzone badania laboratoryjne wykazały, że koagulanty wstępnie zhydrolizowane (Flokor 1, Flokor 1ASW) zapewniły większą skuteczność usuwania zanieczyszczeń organicznych (OWO, RWO) i nieorganicznych (Fe, Mn) z wody podziemnej niż siarczan(VI) glinu, ze względu na większą zawartość polimerowych form glinu. Zakwaszenie wody przed procesem koagulacji do pH=6, bez względu na rodzaj testowanego koagulantu, zwiększyło skuteczność usuwania substancji organicznych oraz zanieczyszczeń powodujących barwę wody, natomiast alkalizacja wody do pH=8,5 zwiększyła skuteczność usuwania związków żelaza, manganu oraz cząstek powodujących mętność wody. Wykazano, że wraz ze wzrostem stopnia polimeryzacji testowanych koagulantów glinowych zmniejszała się zawartość glinu pozostałego w oczyszczonej wodzie, a także wrażliwość koagulantu na zmiany temperatury i pH oczyszczanej wody.

EN

The subject of this research was groundwater from Quaternary formations with the increased concentration of organic substances. Successful treatment of such water generates technological problems and is practically impossible by means of traditional groundwater treatment processes. Laboratory tests showed that the prehydrolyzed aluminum coagulants (Flokor 1, Flokor 1ASW) had higher efficacy of organic (TOC, DOC) and inorganic (Fe, Mn) compound removal from groundwater than alum due to higher content of polymeric aluminum species. Water acidification up to pH=6 prior to coagulation, regardless of the coagulant type, led to an increased efficacy of organic substances and color impurities removal. Moreover, alkalization of water up to pH=8.5 resulted in more efficient removal of iron, manganese and particles being a measure of water turbidity. It was demonstrated that with an increase in polymerization degree of aluminum coagulants both the remaining aluminum concentration in treated water as well as the coagulant sensitivity to changes in temperature and pH of the treated water decreased.

5

Usuwanie PCB i jonów metali ciężkich z wody powierzchniowej w procesie koagulacji

Dąbrowska L., Rosińska A.

Rocznik Ochrona Środowiska

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2013

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Tom 15, cz. 2

1228--1242

EN

The aim of the presented research was to analyse the pollution of the Warta River (Poland) with coplanar PCBs (77, 126 and 169) and heavy metals (Ni, Cd, Pb). Aluminum sulfate and pre-hydrolyzed polyaluminum chloride (PAX-XL10, PAX-XL60, PAX-XL69, PAX-XL1905) were used as coagulants, and the following parameters were analysed in water samples from the Warta River: turbidity, colour, TOC and concentrations of PCBs and heavy metals (Ni, Cd, Pb). Composition of water was modified in order to obtain concentrations of each heavy metal of ca. 0.3 mg/L with implementation of particular amounts of cadmium-, lead nitrate (Cd(NO3)24H2O, Pb(NO3)2) and nickel chloride (NiCl26H2O). In order to obtain concentration of 300 ng/L in case of each congener, a standard mixture PCB MIX3, which consisted of indicator congeners, was added to water. After application of PAX-XL1905, polyaluminum chloride with the highest alkalinity, the best results (among the investigated coagulants) for chosen contaminants removal were obtained; 92% decrease of turbidity and 63% TOC concentration was acquired. In case of heavy metals, best effects were obtained for lead and cadmium removal using PAX-XL1905. Concentration of these metals was reduced from 0.3 mg/L to 0.07 and 0.12 mg/L, respectively. Good results of lead removal were also obtained with use of the other coagulants: PAX-XL60 and aluminum sulfate; its concentrations were decreased to following values: 0.09, and 0.12 mg/L, respectively. When PAX-XL1905 was applied, the residual aluminum concentration in purified water was below 0.05 mg/L, whereas, when aluminum sulfate was used the concentration was below 0.3 mg/L. The highest removal rates for indicator PCBs were obtained with use of aluminum sulfate. Total concentration of PCBs was reduced by 65%. Removal efficiency for particular congeners amounted from 54% (PCB 77) to 72% (PCB 126).

6

Podczyszczanie odcieków ze składowiska odpadów stałych metodą koagulacji, filtracji i ozonowania

Leszczyński J.

Ekonomia i Środowisko

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2013

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nr 4

127--136

PL

Powstające w wyniku składowania odpadów komunalnych odcieki zawierają liczne zanieczyszczenia, wśród których zidentyfikowano łącznie ponad 200 związków organicznych, zawierających głównie jednopierścieniowe i dwupierścieniowe węglowodory aromatyczne, w stężeniach dochodzących nawet do kilkuset µg/dm3. W trakcie składowania odpady podlegają fizykochemicznym i biologicznym przemianom. Zanieczyszczenia powstają głównie w wyniku degradacji części organicznej odpadów, które migrują wraz z wodami opadowymi i roztopowymi, tworząc tak zwane odcieki charakteryzujące się zazwyczaj wysokim stężeniem ChZT, barwy oraz wysoką ogólną zawartością rozpuszczonych soli, głównie chlorków.

EN

The main aim of this work was to examine the application of coagulation and ozonation for the pretreatment of raw leachates. The average characteristics of samples were: pH 8,1, color 5840 gPt/m3, COD 2745 gO2/m3, BOD 250 gO2/m3. The content of substances of total dry residue was 6225 g/m3, electrolytic conductivity 10,6 mS/cm. After coagulation of polyaluminum chloride COD was 1801 gO2/m3, color 2832 gPt/m3, BOD 112 gO2/m3. After ozonation effect removal of COD was 3,3% at the dose of ozone 0,1 gO3/dm3 and 13% (0,7 gO3/ dm3). However, the eff ect of color removal ranged from 6.4% to 24.3%, respectively, at the lowest and highest doses of ozone. The use of ozone after coagulation process allows us to increase the effect of the removal of color and COD at the highest dose of ozone 1 gO3/m3 respectively to 86 and 56%.

7

Wpływ transformacji form glinu na skuteczność oczyszczania wody z zastosowaniem koagulantów spolimeryzowanych

Gumińska J.

Ochrona Środowiska

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2011

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Vol. 33, nr 2

17-21

PL

Skuteczność koagulantów wstępnie zhydrolizowanych w usuwaniu naturalnych substancji organicznych z wody zależy nie tylko od stopnia polimeryzacji koagulantów, ale także od rodzaju usuwanych zanieczyszczeń oraz warunków prowadzenia koagulacji. Na podstawie przeprowadzonych testów ferronometrycznych stwierdzono, że po wprowadzeniu chlorków poliglinu (PACl1, PACl2 i PACl3) do wody, niezależnie od pH, zawartość form monomerowych nie ulegała na tyle istotnym zmianom, aby wpływać na skuteczność koagulacji. Wykazano, że zakres pH wody był czynnikiem wpływającym na mechanizm procesu, który był ściśle związany zarówno z pierwotną charakterystyką koagulantów, jak i formą występowania substancji organicznych w wodzie. W zakresie pH=4,8÷5,0 pro-dukty hydrolizy koagulantów wysokospolimeryzowanych występowały praktycznie w formie rozpuszczonej, natomiast produkty hydrolizy koagulantów o znacznym udziale monomerów zawierały, oprócz rozpuszczonych form glinu, również formy strącone. Podczas koagulacji z korektą pH do 4,8÷5,0, koagulant PACl3 okazał się najskuteczniejszym spośród testowanych reagentów. Stwierdzono, że w zakresie pH=7,5÷7,9 nie zostały stworzone optymalne warunki do usuwania substancji organicznych, gdyż nie zanotowano różnicy w skuteczności oczyszczania wody pomiędzy koagulantem o największym i najmniejszym udziale form polimerowych glinu. Dominującym mechanizmem usuwania substancji organicznych z wody był wówczas mechanizm koagulacji wymiatającej.

EN

The efficiency of pre-hydrolyzed coagulants at removing natural organic matter (NOM) from water is influenced by the extent to which they have been hydrolyzed, by the type of the pollutants being removed, and the conditions under which the coagulation process is conducted. Ferronometry tests have revealed that upon the addition of polyaluminum chlorides (PACl1, PACl2 and PACl3) the change in the content of monomeric species (Al1) was insufficient to exert an influence on the efficiency of the coagulation process, irrespective of the pH applied. However, the pH of the water was found to be a factor that affected the mechanism of the process and was strongly influenced by the characteristics of the coagulants, as well as by the mode of NOM occurrence in the water. Over the pH range of 4.8 to 5.0, the products obtained from the hydrolysis of high-polymerized coagulants practically contained aluminum in dissolved form; when the coagulants being hydrolyzed included a high proportion of monomers, the hydrolysis products contained aluminum not only in dissolved but also in precipitated form. During coagulation in this pH range, PACl3 was found to be the most efficient among the reagents tested. Coagulation conducted over the pH range of 7.5 to 7.9 failed to provide optimal conditions for the removal of organic matter since no difference was observed in the efficiency of water treatment between the coagulant with the highest and the coagulant with the lowest proportion of polymerized aluminum. The dominating mechanism that governed NOM removal under such conditions was the mechanism of sweep coagulation.

8

Phosphorus immobilization in Lake Głęboczek following treatment with polyaluminum chloride

Łopata M., Gawrońska H.

Oceanological and Hydrobiological Studies

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2008

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Vol. 37, No.2

99-105

EN

In 2001-2003, a survey was conducted of the effectiveness of restoration in the heavily eutrophic polymictic Lake Głęboczek, located in Tuchola. The application of the phosphorus inactivation method with polyaluminum chloride PAX 18 resulted in the complete removal of phosphates, and in a considerable (up to 50-60%) reduction of total phosphorus in the lake water. The sorptive capacity of the bottom sediments was enhanced after the restoration, particularly in the top layer (0-5 cm). An increase of the aluminum content and of mineral forms of phosphorus was observed, mainly the aluminum-bound fraction (at its greatest, by over 330%). The amount of mobile phosphorus in the sediments decreased by 40%. The evidence of the durable immobilization of phosphorus in the aquatic ecosystem was the limited phosphorus release from the bottom sediments. This was confirmed by a significant decrease of total phosphorus in the interstitial waters (from 4-6 mg dm-3 to 2-3 mg dm-3), and by a practically complete removal of phosphates from the near-bottom waters.