scholarly journals Removing Iron and Organic Substances from Water over the Course of Its Treatment with the Application of Average and Highly Alkaline Polyaluminium Chlorides

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1367
Author(s):  
Izabela Krupińska
Keyword(s):  
Water Treatment ◽  
Human Consumption ◽  
Iron Ions ◽  
Organic Substances ◽  
Iron Compounds ◽  
Polyaluminum Chloride ◽  
Coagulation Process ◽  
Lack Of Information ◽  
Organic Complexes ◽  
Polyaluminium Chloride

In topic-related literature pertaining to the treatment of water, there is a lack of information on the influence of iron ions in highly basic polyaluminum chlorides on the efficiency of purifying water with increased contents of organic substance. The aim of this work was to determine the changes in the content of organic substances as well as iron compounds in water intended for human consumption following unit treatment processes with particular attention paid to the coagulation process. As coagulants, polyaluminium chloride PAXXL10 with an alkalinity of 70%, as well as polyaluminium chloride PAXXL1911 with an alkalinity of 85% the composition of which also contained iron, were tested. The analysis of the obtained results showed that iron compounds and organic substances were removed to the greatest extent by the coagulation process, which also had a significant influence on the final efficiency of water treatment. The effectiveness of water treatment was determined by the type of tested polyaluminum chloride, which influenced the formation of iron-organic complexes. The reason behind the formation of colored iron-organic complexes during coagulation using PAXXL1911 coagulant was the high pH (approx. 8), at which the functional groups of organic substances, due to their dissociation, are more reactive in relation to iron, and possibly the fact of introducing additional iron ions along with the coagulant.

scholarly journals THE IMPACT OF THE OXIDISING AGENT TYPE AND COAGULANT TYPE ON THE EFFECTIVENESS OF COAGULATION IN THE REMOVAL OF POLLUTANTS FROM UNDERGROUND WATER WITH AN INCREASED CONTENT OF ORGANIC SUBSTANCES

2016 ◽  
Vol 24 (1) ◽  
pp. 70-78 ◽  
Author(s):  
Izabela KRUPIŃSKA
Keyword(s):  
Hydrogen Peroxide ◽  
Underground Water ◽  
Total Iron ◽  
Pollutant Removal ◽  
Organic Substances ◽  
Aluminium Sulphate ◽  
Coagulation Process ◽  
Groundwater Samples ◽  
The Impact ◽  
Polyaluminium Chloride

The article presents the results of studies concerning the impact of the method of Fe(II) ion oxidisation on the effectiveness of coagulation in the removal of pollutants from underground water with an increased content of organic substances (TOC up to 5.338mgC/dm3). In order to oxidise the Fe (II) ions before the coagulation process, the underground water was subjected to aeration, or either potassium manganate (VII) or hydrogen peroxide were dosed in the stoichiometric amount in view of the concentration of Fe (II). The efficiencies of three coagulants were compared: that of aluminium sulphate (VI), polyaluminium chloride (PAX XL-60) and iron (III) sulphate (VI) – PIX-112. Coagulant doses expressed in mgal/dm3 or mgfe/dm3 and changed within the range of 1 to 6 mgal(Fe)/dm3. Volume coagulation was performed in 1-dm3 groundwater samples using 1-minute rapid mix (250 rpm) and 25-minute slow mix (30 rpm) followed by 2-hour sedimentation. It has been proven that the type of oxidising agent and coagulant, as well as their dose, co-determines the effectiveness of the removal of the pollutants. Among the used methods of iron (II) oxidisation, the best effects have been achieved by potassium manganate (VII) with regards to the effects of the reduction of colour, turbidity, concentration of manganese and organic substances, and with regards to the extent of total iron removal, oxidisation with dissolved oxygen was the most effective solution. Hydrogen peroxide was the least useful oxidising agent. Regardless of the oxidising agent the best results in the removal of pollutants in the coagulation process were produced by the coagulant: pre-hydrolysed polyaluminium chloride PAX XL-60, and the worst by the iron coagulant: iron (III) sulphate (VI). Analysis of the results of the studies also showed that the effectiveness of pollutant removal from the underground water in the coagulation process was decreased together with an increase in the value of the TOC/Fetot only in the case of water samples which, after aeration, differed in terms of the coefficient of organic substances and total iron (D). Such a relationship was not found when potassium manganate (VII) and hydrogen peroxide were used for oxidisation before the coagulation process.

scholarly journals Impact of the Oxidant Type on the Efficiency of the Oxidation and Removal of Iron Compounds from Groundwater Containing Humic Substances

Molecules ◽  
2020 ◽  
Vol 25 (15) ◽  
pp. 3380 ◽  
Author(s):  
Izabela Krupińska
Keyword(s):  
Fulvic Acids ◽  
Oxidation Products ◽  
Organic Substances ◽  
Aromatic Rings ◽  
Humic And Fulvic Acids ◽  
Iron Compounds ◽  
Organic Complexes ◽  
High Concentrations ◽  
The Impact ◽  
Adsorptive Properties

Due to the coexistence of organic matter and iron in groundwater, a certain part of the iron is present as iron-organic complexes in the form of colloids and/or dissolved complexes. The study was conducted to evaluate the impact of the type of oxidizing agent: O2, Cl2, H2O2, or KMnO4, on the efficiency of the oxidation and removal of iron compounds from three groundwaters with significantly different contents and types of organic substances among which humic and fulvic acids occurred. This study shows that after the aeration and the oxidation with Cl2 and H2O2, the increasing content of dissolved hydrophilic organic substances containing aromatic rings in the raw water reduced the effectiveness of Fe(II) oxidation and the effectiveness of iron removal during the sedimentation process. This regularity was not found only when KMnO4 was used as the oxidant. After oxidation with H2O2, the highest number of organo-iron complexes and an increased concentration of dissolved organic carbon were found. High concentrations of organo-ferrous connections were also found in aerated water samples. The highest KMnO4 efficiency of removing iron and organic substances and reducing the color intensity and turbidity was due to the catalytic and adsorptive properties of the precipitated MnO2, which also improved the sedimentation properties of the resultant oxidation products.

Determination of natural radionuclides in waste generated in the potable water treatment plants of the Zona da Mata of the state of Pernambuco- Brazil

2019 ◽  
Vol 7 (2A) ◽  
Author(s):  
Adriana Muniz De Almeida Albuquerque
Keyword(s):  
Water Treatment ◽  
Potable Water ◽  
Natural Radionuclides ◽  
The United States ◽  
Radioactive Material ◽  
Human Consumption ◽  
Radiological Protection ◽  
Natural Occurrence ◽  
Water Treatment Plants ◽  
Potable Water Treatment

The water purification procedure aims to obtain a product appropriate for human consumption, minimizing the presence of contaminants and toxic substances present in the water. Among these contaminants, some radionuclides of natural origin, such as uranium, thorium and their descendants, have been identified. Studies have shown that the stages of purification are quite effective in removing the radionuclides contained in water. The removal is due to co-precipitation of the radionuclides with the suspended materials and the precipitated material is accumulated and characterized as a Technologically Concentrated Natural Occurrence Radioactive Material (TENORM) by the United States Environmental Protection Agency (USEPA). This residue can present significant levels of radioactivity and, when discarded in the environment without any treatment, can generate a problem of environmental impact and a risk to the health of the population. In this way, some gamma emitters of the series of U, Th and the K-40 were determined in the residues generated at the Potable Water Treatment Plants – PWTPs in six municipalities of Pernambuco. The results obtain corroborate the classification of the residues generated in the PWTPs as concentrators of the radioactive components contained in the water supplied to the system and reinforce the need for the release to the environment, which is the usual way of disposal of this waste, to be carried out only after considering the radiological protection standards established.

The Forming of Model Colloid System

2014 ◽  
Vol 971-973 ◽  
pp. 266-269 ◽  
Author(s):  
Denis A. Voyno ◽  
Ksenia I. Machekhina ◽  
Ludmila N. Shiyan
Keyword(s):  
Water Treatment ◽  
Zeta Potential ◽  
Electrostatic Interaction ◽  
Organic Substance ◽  
Test System ◽  
Molar Ratio ◽  
Organic Substances ◽  
Mechanism Of Formation ◽  
Iron Silicon ◽  
Colloid System

The paper reports on the creation of a model colloid test system which is similar to groundwater and it can be used as a test system in the water treatment. It is found that at the molar ratio iron/silicon/organic substance is equal to1/7/2 and two orders such as organic substances-Si-Fe and Si-organic substances-Fe, stable colloid system is formed. The mechanism of formation of iron colloid system is described by three steps. The first is the formation of the organosilicon complexes. The second is oxidation of the iron and forming of Fe (OH)3. The last is forming a sol at zeta potential is - 35 mV with electrostatic interaction.

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