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The paper presents the results of a study of parameters used for determining the amount of organic pollutants in wastewater flowing into a collective wastewater treatment plant with a population equivalent of about 120 000 PE. The plant constituted part of a sewage system. Assays were performed for biochemical oxygen demand (BOD5), chemical oxygen demand (CODCr), permanganete index (CODMn) and total organic carbon (TOC). In addition, the pH of wastewater and its alkalinity were determined. Sampling of incoming wastewater and measurement of physicochemical parameters were performed once a week, in the spring. A total of 44 samples of wastewater were collected. The correlations between the individual parameters and the correlations between the ratios of these parameters were determined. It was found that it was possible to estimate, with suffi cient accuracy, the values of selected parameters for determining the concentrations of organic compounds in municipal wastewater, knowing the values of other parameters in this group. Moreover, it was shown that, knowing the relationship between the analyzed parameters, one can find multiple regression equations for a given type of wastewater, which allow one to calculate the remaining relationships with a good fit, i.e. a determination factor R2greater than 0.6

A very low concentration of manganese (Mn) in water is a critical issue for municipal and industrial water supply systems. Mn removal technology is based on the use of manganese oxides (MnOx), especially manganese dioxide (MnO2) polymorphs, under different conditions of pH and ionic strength (water salinity). The statistical significance of the impact of polymorph type (akhtenskite ε-MnO2, birnessite δ-MnO2, cryptomelane α-MnO2 and pyrolusite β-MnO2), pH (2–9) and ionic strength (1–50 mmol/L) of solution on the adsorption level of Mn was investigated. The analysis of variance and the non-parametric Kruskal–Wallis H test were applied. Before and after Mn adsorption, the tested polymorphs were characterized using X-ray diffraction, scanning electron microscope techniques and gas porosimetry analysis. Here we demonstrated the significant differences in adsorption level between MnO2 polymorphs’ type and pH; however, the statistical analysis proves that the type of MnO2 has a four times stronger influence. There was no statistical significance for the ionic strength parameter. We showed that the high adsorption of Mn on the poorly crystalline polymorphs leads to the blockage of micropores in akhtenskite and, contrary, causes the development of the surface structure of birnessite. At the same time, no changes in the surfaces of cryptomelane and pyrolusite, the highly crystalline polymorphs, were found due to the very small loading by the adsorbate.

Coagulation is often used for the pre-treatment of industry wastewater, with effectiveness strictly dependent on technological conditions. This study aimed to determine what technological parameters of coagulation of cosmetic industry wastewater provided the highest efficiency of clarification. The dosages of reagents, the order of dosing, as well as the one- and two-stage processes were investigated. Samples of raw wastewater were collected from average daily effluent from a cosmetics manufacturing plant. Liquid coagulant PIX 111 (FeCl3) and NaOH as a pH-adjusting agent were used. Jar-test experiments were carried out to determine the optimum conditions for turbidity and total organic carbon (TOC) removal. The efficiency of clarification was high (90–99%) across a wide range of pH values (6–9) and coagulant doses (0.5–1.25 mL/L). What is important, the coagulant dose of 0.56 mL/L provided 97.6 % clarification efficiency without the addition of the alkali. The minimal stoichiometric excess of alkalinity for effective coagulation was 0.5 mmol/L. In all samples, the removal efficiency for TOC was lower than for turbidity, because some of the organic carbon forms were non-coagulating dissolved compounds. The wastewater from tonic and fluid production was very susceptible to coagulation. The addition of the coagulant before the alkali resulted in better wastewater treatment efficiency than the reverse order. Single-stage process with optimal doses of the reagents allowed to clarify wastewater to a level of 10 NTU. On the other hand, the two-stage process brought the turbidity down to 1 NTU level.

The study aimed to determine the nature of the kinetics of the manganese sorption process on Ukrainian tuff and basalt at different temperatures characteristic of the natural water environment. The scope of the research included manganese sorption kinetic test on natural mineral sorbents at temperatures of 10, 17.5 and 25 &deg, C in slightly acidic conditions. Sorption (pseudo-first order, pseudo-second order and Elovich models) and diffusion kinetic models (liquid film diffusion and intraparticle diffusion) were used in the analysis of test results. The manganese sorption process on both tuff and basalt proceeded quickly. The dynamic equilibrium state of manganese sorption settled after 35 and 45 min on tuff and basalt respectively. Although the process took place in a slightly acidic environment and below pHPZC of the sorbents, possible electrostatic repulsion did not inhibit the removal of Mn. The Mn sorption on both materials followed the PSO kinetics model. Based on the diffusion kinetic models, it was determined that Mn sorption process on both materials was influenced by diffusion through the boundary layer and intraparticle diffusion. The differences in removal efficiency and rate of Mn sorption in the temperature range of 10&ndash, 25 &deg, C were not found.

This paper reports the results of determinations of crystalline phase type, specific surface area, point of zero charge pH (pHpzc), and Ni(II) sorption capacities of beds for groundwater treatment. Bed materials from iron and manganese removal filters (FeRF, MnRF) as well as a catalytic bed (G1) were investigated. The reference material was MnO2-coated quartz sand (MnQS). The efficiency of Ni(II) sorption was investigated as a function of pH. It was found that the naturally formed coating on FeRF was characterised by the highest sorption efficiency (80–88%) in the wide pH range (4–9) of the solution. Sorption on MnRF was weaker (35–45%). G1 and MnQS, which contained only manganese oxides, were characterised by a very low sorption efficiency of 0–6% and 3–8%, respectively. A lower Ni(II) removal efficiency was observed at an initial pH close to the pHpzc values. During Ni(II) sorption, the pH of the solution was not constant and tended towards the value of pHpzc for all tested materials. The slightly pH-dependent sorption of Ni(II) indicates that its removal depends more on the chemical composition and the specific surface area of the oxide coatings covering the bed materials.

(1) The mineral deposits are the base resources of materials used in building and environmental engineering applications, especially available locally. Two wells of volcanic tuff deposits in the Khmelnytsky region of Ukraine were investigated in this regard. (2) Physical-mechanical, chemical, and mineralogical analyses of the core samples were carried out. (3) The tuff samples were characterized by visible colour, low compressive strength (4.34–11.13 MPa), and high water absorption (30%). The dominant minerals of the upper horizon were chlorite, pyroxene, kaolinite, quartz, hematite, and calcite, while those of the lower horizon included analcime, quartz, hematite, and calcite. (4) The studied volcanic tuffs seem to be only partly useful for construction applications, and considering their visible colour, the exterior decoration of engineering objects could be possible. The peculiarity of the minerals of the upper horizon is that their crystals consist of Fe2+. An analysis of existing scientific data made it possible to say that these minerals can be considered as an alternative to expensive metallic iron in reducing the toxicity of chromium, uranium, and halogenated organic compounds. The significant presence of hematite allows the application of tuffs to technologies of water purification from As5+, As3+, Cr6+, Cr3+, U6+, Sb5+, and Se4+ oxyanions.

The experiment was based on filtration of the highly aggressive water through the melaphyre bed. The quartz bed was non-reactive reference material. The aim of this work was to determine the ability of the melaphyre to remove aggressive CO2 during the chemical reaction. It was noted that a decrease of acidity of the filtrate in comparison to the feed and an increase of its alkalinity and pH. It was calculated that until the moment of exhaustion of the de-acidifying properties of the melaphyre, maximum amount of bound CO2 added to the water was 29.7 g CO2/L of the bed, and maximum amount of the aggressive CO2 removed from the water was 33.3 g CO2/L of the bed. Regarding very high content of the aggressive CO2 (116 mg/L average) in the feed only 28.76% of this component was subject to transformation into bound and affiliated CO2 in the filtrate. For the melaphyre bed the CO2 loss from the experiment system following from desorption was 7.80% of the total load of CO2 added with the feed. On the quartz bed the loss was slightly lower 4.56%.

In this study, we aimed to determine the effect of exogenous stress factors (sodium chloride as osmotic stressor, hydrogen peroxide as an inducer of oxidative stress, white light irradiation, and low temperature) on the biosynthesis of carotenoids and lipids by red yeast (Rhodotorula glutinis, R. mucilaginosa, and R. gracilis) during cultivation in media containing potato wastewater and glycerol. According to our results, the yeast were able to grow and biosynthesize lipids and carotenoids in the presence of the applied stress factors. Low temperature caused an increase in the biosynthesis of intracellular lipids and carotenoids. R. gracilis synthesized lipids (21.1 g/100 gd.w.) and carotenoids (360.4 µg/gd.w.) in greater quantities than that of other strains. Under these conditions, there was also an increase in the content of unsaturated fatty acids, especially linoleic and linolenic acids. The highest percentage of polyunsaturated fatty acid (PUFA) (30.4%) was synthesized by the R. gracilis yeast after cultivation at 20°C. Their quantity was 2.5-fold greater than that of the biomass grown in control conditions. The contribution of individual carotenoid fractions depended both on the yeast strain and the culture conditions. Induction of osmotic stress and low temperature intensified the biosynthesis of β-carotene (up to 73.9% of the total carotenoid content). In oxidative stress conditions, yeast synthesized torulene (up to 82.2%) more efficiently than under other conditions, whereas white light irradiation increased the production of torularhodin (up to 20.0%).

For groundwater treatment, the technologies involving oxidation on MnOx filter bed are beneficial, common, and effectively used. The presence of MnOx is the mutual feature of filter media, both MnOx-coated mineral materials like quartz sand and gravel, chalcedonite, diatomite, glauconite, zeolite, or anthracite along with consisting of MnOx manganese ores. This review is based on the analysis of research and review papers, commercial data sheets, and standards. The paper aimed to provide new suggestions and useful information for further investigation of MnOx filter media for groundwater treatment. The presented compilations are based on the characteristics of coatings, methods, and conditions of its obtaining and type of filter media. The relationship between the properties of MnOx amendments and the obtained purification effects as well as the commonly used commercial products, their features, and applications have been discussed. The paper concludes by mentioning about improving catalytic/adsorption properties of non-reactive siliceous media opposed to ion-exchange minerals and about possible significance of birnessite type manganese oxide for water treatment. Research needs related to the assessment of the use MnOx filter media to heavy metals removal from groundwater in field operations and to standardize methodology of testing MnOx filter media for water treatment were identified.

A high concentration of aggressive carbon dioxide disturbs many technological processes in water treatment. It also causes the development of corrosion in steel and concrete. De-acidification of groundwater by means of air bubbles alters pH and the concentration of aggressive carbon dioxide. This was investigated for the variables of air flow (Q = 20–50 L h−1) and height of water layer (H = 25–75 cm) as well as aeration time (t = 0–20 min). The obtained three-parameter models showed good correlation with the experimental results, except in a few cases where r2 was bigger than 0.9. Furthermore, they allow for prediction of an increase of pH and a decrease in concentration of aggressive carbon dioxide in aerated water. The effectiveness of de-acidification of groundwater was evaluated using indices of water stability (Langelier Saturation Index, Precipitation Index, Ryznar Stability Index, Aggressiveness Index and Index of Aggressiveness). Although as a result of aeration an increase of pH over 7 was observed, the non-corrosive values of the indices were not reached. This was due to a very low alkalinity of water, which was 0.7 meq L−1.

A process based on pre-treatment and membrane desalination was studied for the treatment of the flowback water from drilling for shale gas in Lubocino in Poland. The effectiveness of pre-treatment technology, which contained NaOH alkalization, KMnO4 oxidation, filtration, sorption, and fine filtration, was studied. Also the usefulness of nanofiltration (NF) and reverse osmosis (RO) membranes for flowback desalination was tested. The study was carried out in the semi-pilot scale. The applied pre-treatment technology made possible to obtain a product that can be placed on the NF and RO elements (turbidity = 0.882 NTU, silt density index = 3.1). The 4040-SR100-N2 NF element was ineffective for flowback water purification, and the retention of contaminants was low (5.1% conductivity, 18.2% total hardness, 9.2% TOC). The AG4040FM RO element was characterized by higher retention (conductivity 93.9%, total hardness 98.3%, TOC 78.1%), but low volume concentration ratio (VCR) (VCR = 1.6) with more than 50%...

Applying the coagulation and reverse osmosis for water recovery from evaporative water. Evaporative water from the concentration of yeast slurry is a potential raw material for water recovery. It is characterized by low pH (4.6-6.3), increased turbidity (3.65-13.7 NTU), and high content of total organic carbon (356-754 mg/L). Its treatment in the volume coagulation process using NaOH and coagulant PIX 111, was studied. Water turbidity was lowered to a value below 1 NTU, but coagulation did not allow for the removal of organic compounds. Coagulation was effective at temperatures of 20 and 40°C. Pretreatment of the feed water for RO included alkalization, coagulation, sedimentation, and 5 μm fine filtration (variant I), as well as single 5 μm fine filtration (variant II as a blank). In variant I the feed with improved properties was achieved. Membrane filtration allowed for effective desalination of evaporative water, 98 and 73% conductivity retention was obtained, depending on the method of the feed pre-treatment. The organic compounds were removed less efficiently, at 94 and 84%, respectively.

This paper is a summary of an in-depth study of key factors in the function of a 7-year-old aquaculture system designed for treatment and recycling of domestic wastewater at Stensund, Trosa, Sweden. The reported areas are: wastewater flows, reduction of biochemical oxygen demand (BOD), chemical oxygen demand (COD), phosphorus, nitrogen, and fecal bacteria. Plant production is recorded as harvested biomass, and energy results are given as generated heat and electricity consumption. Special studies were conducted on the reduction of copper by anaerobic treatment. Nitrification was studied with different filter media. Microalgal autofocculation of phosphorus was studied in relation to pH and water hardness for the green algal genus Scenedesmus. Limiting factors for the growth of Daphnia magna in the zooplankton step of the constructed aquatic food-web was studied in a specially designed reproduction test. The results are analyzed in order to optimize the function of the wastewater aquaculture.

Yeast cell wall β-glucans exhibit valuable functional properties, including therapeutic ones. The possibility of using deproteinated potato juice water (DPJW) with the addition of glycerol in yeast culture of Candida utilis ATCC 9950 for biosynthesis of β(1,3)/(1,6)-glucans of cell wall was determined. The biosynthesis of β-glucans was preferably intensified by media prepared from DPJW at pH 5.0 with 5 or 10 % addition of glycerol. Cells from these cultures were characterized and found to possess thickest cell walls and β-glucan layers. The content of β-glucans in the walls’ preparations was estimated to be approximately 44–45 % and was significantly higher in comparison with the content after culturing in synthetic YPD medium (approximately 31 %). The new developed media may be used in the production of C. utilis biomass with enhanced content of functional β-glucans. It creates the possibility of a favorable, simultaneous management of waste potato juice water and glycerol in the formation of β(1,3)/(1,6)-glucans.