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1
Content available remote Unieszkodliwianie ścieków z produkcji trotylu w warunkach przemysłowych
PL
Trotyl (2,4,6-trinitrotoluen) stanowi jeden z najczęściej produkowanych materiałów wybuchowych. W przemyśle oczyszcza się go za pomocą procesu siarczynowania, w którym powstają toksyczne i trudne do unieszkodliwienia ścieki zwane czerwonymi wodami. Ścieki te są silnie toksyczne dla środowiska naturalnego i muszą być unieszkodliwiane. Przegląd literaturowy pokazuje, że ich unieszkodliwienie jest zadaniem trudnym, gdyż zanieczyszczenia słabo poddają się procesowi degradacji. Aby je usunąć, stosuje się wiele metod, ale do tej pory nie ma w pełni satysfakcjonującej metody oczyszczenia czerwonych wód. Z kolei opracowanie nowej metody syntezy trotylu wymaga opracowania nowych technologii, a synteza nie jest oparta na tanich i łatwo dostępnych surowcach.
EN
A review, with 91 refs., of the impact of wastewater from TNT prodn. (red waters) on the environment and methods of their neutralization (biol., chem., pptn., oxidn., adsorption, combustion, and concn. methods). New TNT prodn. processes were also discussed.
PL
Omówiono wyniki laboratoryjnych badań dotyczących procesów zaawansowanego utleniania zastosowanych w celu odbarwienia roztworów błękitu metylenowego (MB). Zbadano układy utleniające wykorzystujące rodniki siarczanowe oraz hydroksylowe. Stopień odbarwienia roztworu zawierającego MB wyniósł 28–96% po 20 min reakcji. W warunkach doświadczalnych, w reakcjach prowadzonych w obecności rodników siarczanowych uzyskano wyższy stopnień rozkładu barwnika niż w reakcjach prowadzonych w obecności rodników hydroksylowych. Współczynnik korelacji (R²) wykazał, że reakcje zachodziły zgodnie z kinetyką reakcji pseudo-pierwszorzędowej.
EN
A 20 mg/L methylene blue (MB) aq. soln. was oxidized in the presence of Na₂S₂O₈ and UV radiation or O₃ and H₂O₂. The decoloration were carried out continuously for 20 min. Samples for anal. were taken after 5, 10, 15 and 20 min. MB content before and after the advanced oxidn. processes was detd. by the UV spectrophotometric method. A higher degree of MB decompn. was obtained in the presence of sulphate radicals (96%) than hydroxyl radicals (70%) after 20 min of the process.
EN
Bentonite clay was utilized in this research as adsorbent element to remove the lead and copper ions from wastewater. Series of tests were performed at multiple parameters, such as pH solution, initial concentration of lead and copper ions, adsorbent mass, and contact time. The greatest removal was attained at pH 5, adsorbent weight of 0.5 g, initial heavy metal concentration of 10 mg/l, and a contact time of 60 minutes. The results revealed that bentonite clay is suitable in the removal of metal ions from polluted water. The ion exchange rate of lead was faster than that of copper. The isotherm for the adsorption of the lead and copper ions on bentonite clay was confirmed by the Freundlich and Langmuir isotherms which offered good consequences. The results indicated that bentonite was utilized as an efficient ion exchange element for the removal of heavy metal ions from polluted water. Fourier Transformed Infrared Spectrophotometer (FTIR) images of bentonite clay before and after adsorption showed the imbibition of metal ions by bentonite clay.
EN
The marine diatom Chaetoceros muelleri is commonly used for aquacultural feed and is well known for its fast growth and easy maintenance. In order to evaluate the potential of C. muelleri to be used for the nutrient removal and biomass production from eutrophic saline wastewaters, the algae were cultured under a wide range of temperature, salinity, photoperiod, and light intensity. The optimum temperature for the biomass production was observed at 30°C, but the algae could maintain at least 66% of the highest production between 20°C and 35°C. The optimum salinity for the biomass production was 25, but the algae could maintain at least 22% of the highest production between 10 and 30. Both light intensity and photoperiod affected the algal biomass production, and the minimum light requirement was considered 100 μmol m−2•s−1 for 6 hours to maintain the biomass production and nitrogen (N) and phosphorus (P) absorption. Throughout all the experiments, the N and P absorption increased with the biomass production, but the ratio of N and P to the biomass exponentially decreased with the biomass production. These results showed that C. muelleri is tolerant to the wide range of environmental conditions, absorbing nutrients and producing organic matter. C. muelleri has a great potential to be introduced in the water treatment processes, especially where the temperature and salinity fluctuate.
EN
The wastewater quality index (WWQI) can be defined as a single value, which reflects the overall wastewater quality related to its input constituent parameters. The major objective of the present study was to investigate the suitability of the effluent quality from Meet Abo El-koum wastewater treatment plant in Egypt for safe disposal based on the wastewater quality index approach. Moreover, statistical analysis was applied to develop a simple model using multiple linear regression (MLR) for accurate prediction of WWQI depending on different wastewater quality parameters. The results indicate good quality of the treated wastewater for safe disposal in general. Moreover, it is apparent that about 17% of the WWQI values reached excellent quality referring to the classification of the WWQI levels. For greater simplicity, a relationship between BOD5 and COD was deduced using linear regression, so that the results of the BOD5 analyses that appear after five days can be skipped. This approximation can be used to calculate WWQI on a specific day given the results of the treated wastewater analyses on that day.
EN
Wastewater contamination which causes health, environmental and economic impacts is one of the most common environmental issues. Several methods have been used for the upgrade of the existing wastewater treatment facilities, nevertheless, the application of phytoremediation treatment is a promising and environmentally friendly method to avoid the secondary contaminations posed by the treatment dosage in other advanced treatment methods. The current work aimed to assess the phytoremediation treatment of the pre-treated domestic wastewater using the Salvinia molesta and water hyacinth plants. The water quality tests were performed in the current research to evaluate the effects of the phytoremediation treatment using the Salvinia molesta and water hyacinth plants on the responses of the water quality parameters. The study focused on varying two main parameters, namely the pH and the hydraulic retention time (HRT), while the removal rate was determined based on the reduction in the chemical oxygen demand (COD), total dissolved solids (TDS), total nitrogen (TN) and turbidity. The optimal removal of COD, TDS, TN and turbidity in the current study was 56.47, 83.00, 52.12, and 79.98% for Salvinia molesta as well as 48.81, 24.00, 13.56 and 19.89% for water hyacinth.
EN
Nonthermal plasma discharge is used for the decolourization of dyes used in textile industry. Two dyes were considered, namely methylene blue and malachite green in aqueous solution. Plasma was generated by a Pin-water surface DBD between a metal pin electrode placed in air and the surface of an aqueous dye solution filling a glass container. Active radicals, especially hydroxyl radicals, generated by plasma in air penetrated the aqueous dye solution and induced the oxidizing reactions leading to the dyeing material disintegration. The measurements of solution parameters, including pH, oxidation-reduction potential, and conductivity can help to optimize the plasma decolourization efficiency of the two dye solutions. It was found that the pH values of the two dye solutions decrease with the increasing plasma treatment time. This is accompanied by an increase of the oxidation-reduction potentials and conductivities. The concentration of hydrogen peroxide formed in the two dye solutions during plasma treatment was found to increase with the plasma treatment time. The decolourization efficiencies of the two dye solutions increase with plasma treatment time and can be related to the solution parameters, including reduction of the pH values, increase in the oxidation-reduction potentials as well as solution conductivities and increase of hydrogen peroxide during the plasma treatment time.
8
Content available Pharmaceuticals in water and wastewater - overview
EN
The paper presents concentrations of pharmaceuticals in surface water and sewage. Special attention was paid to the content of estrogens in municipal sewage and the method of their disposal. Concentrations of various pharmaceuticals in raw and treated wastewater were compared and the pharmaceuticals in different countries and waters were presented in tables. The most frequently identified drugs in sewage are sex hormones (etradiol, ester, ethinylestradiol, 17 β-estradiol) and the antiepileptic drug Carbamazepine. These drugs are difficult to remove from water and therefore appropriate treatment processes are used, such as: adsorption on active carbon, UV irradiation, etc. Contamination of water with pharmaceuticals has a negative impact on the development of aquatic organisms and can lead to serious human health problems.
PL
W pracy przedstawiono stężenia farmaceutyków w wodach powierzchniowych oraz ściekach. Szczególną uwagę skupiono na zawartości estrogenów w ściekach komunalnych oraz na sposobie ich usuwania. Porównano stężenia różnych farmaceutyków w ściekach surowych oraz ściekach oczyszczonych, a także zostały przedstawione tabelarycznie farmaceutyki występujące w różnych państwach oraz wodach. Najczęściej identyfikowanymi lekami w ściekach są: hormony płciowe (etradiol, estron, etinyloestradiol, 17 β-estradiol) oraz lek przeciwpadaczkowy – Karbamazepina. Leki te są ciężko usuwalne z wód, dlatego też stosuje się odpowiednie procesy ich oczyszczania, takie jak: adsorpcje na węglu aktywnym, naświetlanie promieniami UV itp. Zanieczyszczenia wód farmaceutykami wpływa negatywnie na rozwój organizmów wodnych, a także może prowadzić do poważnych problemów zdrowia ludzkiego.
9
Content available Occurrence of pharmaceuticals in surface waters
EN
This is a short review on the increasing problem of pharmaceutical pollution in surface waters. Non-steroidal anti-inflammatory drugs (NSAIDs) are medicines that are widely used to relieve pain, reduce inflammation, and reduce a high body temperature. The paper presents a literature review on the content of NASIDs in surface waters. Due to the continuous growth of the world's population and the increasing use of pharmaceuticals, the threat to aquatic ecosystems is increasing. Every day, huge loads of pollution are discharged into rivers and seas. Depending on used technology the effectiveness of wastewater treatment varies considerably. The level of removal efficiency by wastewater treatments depends on physicochemical properties of the individual pharmaceutics and on the type of wastewater treatment technology. Therefore, it is recommended to conduct research on removal efficiency of main drug residues in Polish wastewater treatment plants and, if necessary, apply the best available technologies in this area.
EN
Purified (in acetone, at 50° C for 72 h), post-consumer PVC waste was grafted with 1,4-benzodioxane6-amine and 2-aminobenzimidazole to increase its ability to remove ions from wastewater (from the Beja region, Tunisia). The PVC waste was characterized by IR spectroscopy, differential thermal analysis (DTA) and elemental nitrogen analysis. The ability of modified PVC waste to remove ions [sulphates ions (SO4 2-), nitrates ions (NO3 -), chloride ions (Cl-), carbonates ions (CO3 -), metal ions (Mg2+, Zn2+, Na+, K+…)] from wastewater was assessed based on ion conductivity measurements. It was found that modified PVC waste shows a greater efficiency in the removal of ions from wastewater than unmodified waste.
PL
Oczyszczone (w acetonie, w temp. 50°C przez 72 h), poużytkowe odpady PVC szczepiono 1,4-benzodioksano-6-aminą i 2-aminobenzimidazolem w celu zwiększenia ich zdolności do usuwania jonów (SO4 2-, NO3 -, Cl-, CO3 -, Mg2+, Zn2+, Na+, K+…) z wód ściekowych (z regionu Beja, Tunezja). Odpady PVC scharakteryzowano za pomocą spektroskopii IR, różnicowej analizy termicznej (DTA) i analizy elementarnej azotu. Zdolność odpadów PVC do usuwania jonów znajdujących się w wodach ściekowych oceniono na podstawie pomiarów przewodnictwa jonowego. Stwierdzono, że modyfikowane odpady PVC wykazują większą skuteczność usuwania jonów znajdujących się w ściekach niż odpady niemodyfikowane.
EN
The present study deals with nickel ions removal from dilute aqueous solution by ion flotation with emphasizing the process efficiency. The effect of collector structure on ion flotation efficiency and water recovery was evaluated using anionic collectors of sodium dodecyl sulfate (SDS) and functionalized graphene oxide by 2,6-diaminopyridine (AFGO). The results showed that process efficiency enhanced with the increase in pH and reached to complete removal at pH of 9 and 9.7 for SDS and AFGO, respectively. The AFGO showed the multifunctional bindings for complex formations with nickel ions. A coordinate bond may be formed between nickel ions and AFGO at the pH of 9 which increased nickel ion removal. The water recovery as a critical parameter that contributes to removal efficiency was significantly affected by the collector structure. The AFGO doesn’t have a frothing property and so decreases the water recovery during the process. The AFGO had significantly lower water recovery than SDS (almost threefold).
EN
This work aims to evaluate the treated wastewater from the activated sludge treatment plant in the City of Sidi Bel Abbes (North-Western Algeria) which is required for reuse in irrigation. The control of irrigated areas downstream is done based on a pedological study. Physico-chemical analysis such as (pH, BOD5, COD and SS) indicate results in Algerian and international standards required by the WHO. The Sodium Adsorption Ratio and Electrical Conductivity values of the treated wastewater belong to the C3-S1 class. The treated wastewater has a fairly good microbiological quality that meets Algerian standards. The helminth eggs are practically absent. The concentrations of heavy metals are much lower than the limits prescribed in the Algerian decrees. Therefore, the overall processing plant efficiency is satisfactory and has the characteristics of a good treated water quality for reuse in the field of irrigation while protecting the environment. The pedological study of the soil samples shows that the most dominant fraction is undeveloped calcimagnetic. The planned irrigation plain covers an area of about two thousand hectares. Depending on the crops to irrigate; the development and nature of the necessary or recommended improvements, the proposed irrigation perimeter could be classified into five categories in which only three categories are irrigable. Water projects have been proposed to ensure the irrigation of three subdivided sectors.
EN
The remarkable development of sanitation in Morocco has inevitably led to the production of sludge generated from wastewater treatment plants in increasing quantities. Consequently, the problem of sludge management becomes persistent and worrying. The aim of this paper was to contribute to the study of sewage sludge management issue in Morocco by identifying the various constraints hampering the sustainable disposal and/or recovery of municipal sewage sludge and drawing up recommendations for the decision-makers. Moreover, in the context of improving by learning from best practices and seeking common solutions regarding this problematic, benchmarking with other countries has been conducted as well. To carry out this study, a methodological approach was defined based on bibliographic research, surveys, interviews and benchmarking. The constraints hampering the sustainable management of sludge are numerous and complex, they have not been technical and environmental but also a regulatory, institutional-organizational and economic-financial nature yet. Therefore, municipalities, government and academia ideally would be encouraged to participate in the decision-making process regarding the management of sewage sludge. Technical solutions, when coupled with stakeholder participation, can lead to policy implementation with a higher chance of improving the present situation. In the case of Morocco, when comparing with others sludge recovery and disposal routes, land application (reuse in agriculture, silviculture and rehabilitation of degraded soils) remains the most environmentally friendly option, as well as a sustainable and economically viable solution.
EN
Anaerobic digestion (AD) is an adequate alternative to treat wastewater generated from fruit and vegetable processing (FVWW); likewise, in recent years, artificial wetlands (AWs) have been applied as a post-treatment process for anaerobically pre-treated wastewater. The objective of this work was to design a sustainable treatment system for FVWW composed of upflow anaerobic reactors (UASB) with phase separation and an AW system that receive the anaerobically pretreated effluent. Using the design methodologies for the UASB reactors and artificial wetlands with sub-surface flow (AW-SSF), the parameters of the combined AD-AW system that treat a wastewater flow of 300 m3∙d–1 were calculated. The UASB acidogenic system was adjusted to a hydraulic retention time (HRT) of 10 h and organic loading rate (OLR) of 13.84 kg COD m–3∙d–1; meanwhile, the methanogenic and cascade UASB reactors with OLRs of 10.0 and 3.0 kg COD m3∙d–1, and HRTs of 11 and 10 h, respectively, achieve a high COD removal efficiency (above 94%), and an overall biogas production rate of 1.53 m3 of biogas per m3 of reactor capacity per day. According to the results obtained with the theoretical design, anaerobic-wetland combined system achieves an overall efficiency greater than 98%. The wastewater treated by the proposed system will allow the reuse of 30% of the water used in the washing of fruits and vegetables.
EN
The pressure on the use of water and climate change has caused a decreased availability of water resources in semi-arid areas in the last decades. The Setif Province is one of the semi-arid zones of Algeria as it receives an average less than 400 mm∙year–1. The question of the evolution of demographic pressures and their impacts on water resources arise. By applying WEAP software (water evaluation and planning), the aim is to develop a model of water resources management and its utilization, assess the proportion of the resource-needs balance and analyse the future situation of water according to different scenarios. This approach allows to identify the most vulnerable sites to climatic and anthropogenic pressures. The estimation of the needs for drinking water and wastewater in the Setif Province has shown that these needs increase over time and happening when the offer is not able to cover the demand in a suitable way. It is acknowledged that there is a poor exploitation of water resources including underground resources, which translates into unmet demand in all sites of demand.
EN
The article deals with the main methods of nutrient removal from wastewater, as well as presents promising technologies and techniques. Struvite was characterized by a complex phosphorus fertilizer. The influence of struvite on the processes of germination of cultivated plants was investigated. The possibility of creating a growth substrate as an inexpensive and effective alternative to the disposal of the man-made wastes that contain an organic component was identified. The composition of the growth substrate was selected to ensure its functional properties. The growth substrate was tested by bioindication. Subsequently, the modification of the substrate by adding natural sorbents.
EN
The batik industry is one of the Indonesian economic drivers. However, most of the batik industries discharge their wastewater without any prior treatment, thus endangering the environment. This research aims to investigate the ability of hybrid constructed wetlands (CWs) system using Canna indica in the batik wastewater treatment. The parameters studied were chemical oxygen demand (COD), total suspended solid (TSS), and oil and grease (FOG) with 3, 5, and 7 days of hydraulic retention time (HRT). The results indicate that the hybrid constructed wetland system using Canna indica optimally gains the COD and FOG removal efficiency on day 3 at 89.61% and 89.53%, while the TSS removal efficiency on day 5 at 98.74%. Despite the high removal efficiency, the effluent parameters remain below the standards for direct discharge into waterbodies. Therefore, further research is needed to investigate the appropriate pre-/advanced treatment to be combined with the hybrid constructed wetland in batik wastewater treatment.
EN
The possibilities of using a natural sorbent – peat for the wastewater treatment of ammonium ions and phosphates discharged from runoff into natural reservoirs at high concentrations were investigated. The peat of from the Vereshchytsya-Yanovske deposit of Ukraine of two depths: lowland and upland, was studied. It was established that the lowland samples of peat have higher sorption properties to the investigated pollutants from the aquatic environment than the upland ones. A greater moisture loss in the lowland peat species was observed, as well as the major part of the plant fibers in its structure, which explains its sorption properties. Due to the high content of humic substances, the extraction of cations from the water by peat can occur due to the ion exchange. The adsorption isotherms of both ammonium and phosphate ions on the top and lowland peat species of the Vereshchytsya-Yanovske deposit were constructed and presented. The adsorption isotherm obtained in the experimental studies was used to mathematically establish the isotherm equation, using the Langmuir and Freundlich models to describe the equilibrium of the sorption processes under study. The degree of appropriation of linear equations to the experimental data was evaluated on the basis of the deterministic coefficient, which enabled to determine that in each case the Langmuir equations describe the adsorption isotherms more adequately.
19
Content available Study of the Magnetic Water Treatment Mechanism
EN
The main problem of widespread introduction of magnetic water treatment (MWT) in the processes of water and wastewater treatment is the lack of modern research aimed at studying the mechanisms of MWT effects, in particular the influence on the physicochemical properties of aqueous solutions. This study explains the effect of MWT taking into account the physical and chemical properties of aqueous solutions due to the presence of the quantum differences in water molecules. All of the MWT effects are related to the change in the physicochemical properties of aqueous solutions. It is due to the presence of two types of water molecule isomers and their librational oscillations. The result of MWT is a violation of the synchronism of para-isomers vibrations, with the subsequent destruction of ice-like structures due to the receiving of energy from collisions with other water molecules (ortho-isomers). One of the most important MWT effects includes the change in the nature and speed of the physicochemical processes in aqueous solutions by increasing the number of more physically and chemically active ortho-isomers. The MWT parameters specified in the work allow explaining the nature of most MWT effects and require developing the scientific and methodological principles for the implementation of the MWT process and mathematical modeling of the MWT process in the water and wastewater treatment. It can be used in the design of the MWT devices taking into account the constructive and mode parameters of MWT devices.
20
Content available Sludge of Oil Refining Units and Their Processing
EN
The article presents the quantitative characteristics of multi-tonnage technogenic wastes in Ukraine and the IvanoFrankivsk region, which cause environmental pollution. The water silts containing petroleum products are particularly dangerous wastes. It is proposed to recycle them using the method of preparation of the raw mixture in composition with the following technogenic wastes: oil sludge, ash, zeolite material, calcium-containing compounds, and organic mineral binders. They are granulated and subjected to the thermal treatment at low temperatures. The granular materials made using the oil-containing silt of the model object reduce the negative impact onto the environment of the region and increase its level of environmental safety.
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