Environmental applications of carbon nanotubes (CNTs) have recently attracted worldwide attentiondue to their excellent adsorption capacities and promising physical, chemical and mechanical properties, as well asthe preparation of novel membranes with attractive features for water purification. This paper critically reviews therecent progress on the preparation and applications of CNT based membranes in water and wastewater treatment. Various synthesis techniques for the preparation of CNT based membranes are discussed. The functionalization ofCNTs, which involves chemical/physical modification of pristine CNTs with different types of functional groups,improves the capabilities of CNT for water and wastewater treatment and/or removal of waterborne contaminants.The CNT-based membrane applications are found to possess a variety of advantages, including improving waterpermeability, high selectivity and antifouling capability. However, their applications at full scale are still limitedby their high cost. Finally, we highlight that CNT membranes with promising removal efficiencies for respectivecontaminants can be considered for commercialization and to achieve holistic performance for the purpose ofwater treatment and desalination. This paper may provide an insight for the development of CNT based membranesfor water purification in the future. With their tremendous separation performance, low biofouling potential andultra-high water flux, CNT membranes have the potential to be a leading technology in water treatment, especiallydesalination.

The impacts of industrial wastewater contamination on the geotechnical properties of clayey soil have been studied in the research presented in this paper. The contaminant in question is industrial wastewater released from Thi-Qar oil refinery as a by-product of production, and the soil samples obtained from Thi-Qar oil refinery plant in Al-Nassyriah (a city located in the south of Iraq). The geotechnical properties of contaminated soil samples were compared with those of intact soil to measure the effects of such a contaminant. The soil samples were obtained from three locations in the study area; representing the highly contaminated area, the slightly contaminated area, and the intact area used as a reference for comparison of test results. The results of the tests showed that the contaminant causes an increase of natural moisture content, field unit weight, Atterberg’s limits, and maximum dry unit weight, as well as an increase of the compression index and the coefficient of vertical consolidation. Also, the contaminant causes a decrease in specific gravity, the optimum moisture content initial void ratio, the swelling index, the coefficient of permeability, and cohesion between soil particles.

This paper deals with the results of chemical pre-treatment of effluents from Chip Washing by coagulation. Three different, most frequently used coagulants i.e. calcium hydroxide, aluminium sulphate and ferric chloride were applied. Influence of single and simultaneous dosage of the reagents was investigated. Fully randomized block systems were applied in the factorial variance analysis and final approximation analytic-empiric mathematical equations with application of the central point method were formulated.

The results of ecotoxicological investigation of chosen components of textile wastewater have been presented. There were two detergents Awiważ and Tetrapol and one anthraquinone dyestuff. The toxicity of the compounds were checked by means of microbiological methods with the use of bacterial strains. In the case of pure cultures (Vibrio fischeri, Escherichia coli, Bacillus subtilis) the values of effective concentration EC50 were found to be almost the same for a given compound with the use of various bacteria. Application of the test with mixed cultures from activated sludge gave difTerent results in EC50 for the investigated dyestuff.

The Henaya Irrigated Perimeter (HIP) is an agricultural area irrigated by treated wastewater (TWW) of Ain El Hout treatment plant. Various analyses have shown that i) this water has low concentration of heavy metals and toxic elements, ii) the average values of the physicochemical parameters for 136 samples are satisfactory (29.2 mg O2∙dm–3 for chemical oxygen demands – COD, 13.14 mg O2∙dm–3 for biological oxygen demands – BOD, 14.2 mg∙dm–3 of suspended matter – SM, 1.82 mg∙dm–3 of N-NO3, 7.7 for pH and 927.74 μS∙cm–1 for electric conductivity – EC). Thirdly, it contains a high number of bacteria and nematodes (7200 CFU∙(100 dm3)–1 for faecal coliforms and 30 eggs∙dm–3 for intestinal Nematodes) which makes it dangerous for groundwater contamination. The objective in this work is to characterize the TWW and evaluate the impact of it use for irrigation on the quality of Hennaya groundwater. Before this, one has to prove that there is an amount of TWW that feeds the water table to show that there is a risk of pollution. We then estimated the aquifer minimum recharge value by TWW using the Thormthwaite meth-od. The estimation has given 92 mm which is an important quantity. The results of the groundwater microbiological anal-yses reveal no sign of contamination. The cause is the efficiency of the degradation of pollutants of the Vadose zone. The soil purifying power Md of the HIP was evaluated by the Rehse method and gave values ranging from 2.1 to 12.7 which indicated a complete purification.

The goal of the presented research works was to prove the following thesis: Does the process of contaminants reduction and effluent application for arable land fertilization justify the treatment method of waste water from yeast production facility in soil and plant environment? In order to achieve the above mentioned goal, basically the dynamics of physical and chemical properties change observed for waters, soils and plants irrigated with wastewater from yeast factory has been studied for many years. Part II presents the problems connected with the impact of irrigation with wastewater from yeast factory on soil physical and chemical properties and on the quantity and quality of arable plants yield. Soils irrigated with process effluent from yeast factory show overfertilization with potassium. Also reduction of the organic carbon ratio to nitrogen is observed due to redundancy of potassium and deficit of organic carbon. Activities aimed at preventing reduction of organic substance consist in: straw, beet leaves and other solid organic waste ploughing. In industrial - grain crops rotation applied in the fields used for agricultural utilization of wastewater carried out in the research years of 1993-1997, an increase of yields (average for grain - by 13% and for root beet by 0.5-10.7%) was recorded. It was higher than in the case of yields produced on yeast production facility fields not irrigated with effluent and yields obtained by individual farmers from fields intensively treated only with mineral fertilizers. In comparison to the literature data the impact of irrigation with yeast effluent, the grain yields of winter wheat, spring barley and winter rape show slightly increased percentage contents of proteins, nitrogen, and potassium, whereas the contents of calcium and magnesium were smaller.

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 rec-ommendations 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 tech-nical 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 re-garding 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 ag-riculture, silviculture and rehabilitation of degraded soils) remains the most environmentally friendly option, as well as a sustainable and economically viable solution.

There are two kinds of wastewater that may originate at a dairy plant: post-production and nonproduction waste. Dairy wastewater treatment is a process consisting of several stages. In the pre-treatment stage, fat and sand is removed from wastewater. The second stage treatment consists mainly in aerobic treatment with activated sludge, advanced oxidation methods and an anaerobic treatment. In recent years, more and more plants have been treating their wastewater in SBR type reactors, because they are flexible at work and enable the user to change conditions to suit the variable quality of raw wastewater. The research on the kinetics of the wastewater treatment process in an SBR reactor has been conducted. The removal of several factors such as nitrogen compounds, TOC, phosphorus and the kinetics of oxygen concentration and redox potential have been analyzed. The experiment was carried out in two 12 dm3 volume SBR reactors in a lab-scale. The SBR reactors were operated with a cycle time of 12 hours with three hours of filling, seven hours of aeration, an hour of sedimentation, half an hour of decantation and half an hour of technical break. In presented research average parameters of raw wastewater were: TOC 329 mg C/dm3, ammonium nitrogen I I. 15 mg NN1,/dm3, and total phosphorus 15.42 mg P/dm3.

Photocatalysis is an efficient and ecological method of water and wastewater disinfection. During the process, various microorganisms are deactivated, including Gram-positive and Gram-negative bacteria, for example Escherichia coli, Staphylococcus aureus, Streptococcus pneumonia, and so on, fungi like Aspergillus niger, Fusarium graminearum, algea ( Tetraselmis suecica, Amphidinium carterae, and so on) and viruses. Titanium dioxide (TiO2) is the most commonly used material due to its price and high oxidation efficiency; it is easy to modify using both physical and chemical methods, what allows for its wide use in industrial scale. Intensive research on novel photocatalysts (e.g. ZnO and carbon based photocatalysis like graphene, carbon nanotube, carbon nitride and others) has been carried out. The future development of nano-disinfection containing metal/metal oxides and carbon based nanoparticles should focus on:
 improving disinfection efficiency through different manufacturing strategies,
 proper clarification and understanding of the role and mechanism of interaction of the nano-material with the microorganisms,
 progress in scaling up the production of commercial nano-photocatalysts,
 determination of the extent of environmental release of nano-photocatalysts and their toxicity.

Using microorganisms in eliminating or reducing the impacts of harmful remnants is very ancient manner. The current study was conducted to explore the potential of utilizing some fungi species that isolated from the main sewage treatment plant in Al-Muamirah area, Babylon-Iraq, in reducing some pollutants. Six fungi taxa Aspergillus flavus, A. niger, A. terrues, Candida albicans, C. krusei, and Penicillium digitatum were identified before any treatment process, whereas only four fungi species A. flavus 20%, A. niger 20%, A. terrues 10%, and P. digitatum 18% were recognized after completing the physical and chemical treatment stages. Only three taxa A. niger, A. terrues, and P. digitatum were employed to reveal their capability in treating the sewage water, which represent the biological treatment stage as the final step of the treatment processes. The results showed a considerable capability of these fungi species in decreasing many variables values such as pH, total soluble solids (TSS), electrical conductivity (EC), salinity, total alkalinity, chlorides, nitrite, and phosphate. Where, slightly low reduction was detected in TSS value in all experiments (1.1–5.9%), similarly, both EC and salinity which were decreased with low ratios (6.6%, 3.9%, respectively). Taxon A. terrues exhibited high ability in reducing the total alkalinity and chloride ions in the treated water (30.9%, 43%, respectively) in comparison with the other two fungi species. Furthermore, all three fungi species were posed high capability in decreasing nutrients, where both nitrite and phosphate ions were highly reduced (87–97% and 22.8–32.1%, respectively). Based on these findings, we suggest using other microorganisms and exploring their capacity in removing the pollutants, and revealing the ability of the above fungi taxa in removing other pollutants.

The production of biofuels using wastewater as a microalgae culture medium is a little explored technology, but with potential for success. In order to contribute to the knowledge of these technologies and their technical feasibility for microalgae growth, in this work the Chlorella sp. strain was cultivated in two types of effluents generated in an experimental farm located in eastern Colombia, before and after a biological treatment process. The consumption of the main nutrients that regulate growth and lipid production was evaluated, in order to extract, quantify, characterize and convert them into biodiesel. The results showed that Chlorella sp. growth and lipid production is more favourable in R2 medium of treated water than in R1 medium of raw water, mainly due to phosphorus limitation and higher N-NO3 concentration in R2 compared to R1. In the R2 medium culture, a percentage of 42.54% of long-chain fatty acids was found, which is necessary to obtain a high quality biodiesel. Finally, the best transesterification experiment allowed reaching a fatty acid methyl esters (FAME) percentage of 90.1 ± 2.7%. In general, the results demonstrated the potential viability of using the wastewater generated in the San Pablo farm to produce biomass with lipid content to obtain biodiesel, finding that where the concentration of nutrients, mainly nitrogen, has a great influence on the microalgal metabolism for lipid accumulation.

The primary objective of the present study was to determine the seasonal dynamics of ciliates in activated sludge. Studies were carried out in order to verify the hypothesis that fertility of a habitat may significantly influence the seasonal dynamics of the abundance of ciliates, as well as the number and intensity of correlations between physic-chemical parameters and ciliates. It seems that the values of numbers of ciliates were seasonally changeable. The highest numbers of ciliates were found in spring and summer, however the lowest numbers of ciliate communities were noted in winter. The studies showed that protozoa community is determined by ammonia mainly in summer. In spring and winter additional factors may be important. Probably suspended solid, total organic carbon and concentration of appropriate food (bacteria and flagellates) are the major regulator of abundance of ciliates.

In the present investigation we have studied the effects of static magnetic field on removal of organic compounds and ammonium nitrogen by high loading activated sludge. The research was carried out on laboratory scale at room temperature. Three or two continuously operating test systems were used in the experiment. In two test systems the return activated sludge was exposed to magnetic field strength of 20 mT or 40 mT. The magnets were attached to a pipe used for activated sludge recirculation. The nitrification rate for test systems when the return activated sludge was exposed to magnetic field was higher than for control system in absence of magnetic field. The best data was observed for test system which was exposed to magnetic field of 40 mT. The nitrification rate was 2 times higher than for control system when the loading of activated sludge was in the range of 0.6 to 0,9 g COD/gMLSS ·d for. The results show that magnetic field improves nitrification of domestic wastewater by high loading activated sludge.

In the present investigation we studied the effects of static magnetic field on transformation of organic compounds and ammonium nitrogen. The research was carried out on laboratory scale at room temperature. Two continuously operating test systems were run in parallel. In one of the systems the raw sewage was exposed to magnetic field strength of 180 mT. The magnets were attached to a pipe used for raw sewage. The second system was used as a control. The research was carried out without activated sludge and with activated sludge. The investigation carried out in an experiment without activated sludge showed that the removal of COD for system with the raw sewage exposed to magnetic field strength of 180 mT was 15% higher then system in absence of magnetic field. During investigation carried out in an experiment with activated sludge it was observed that the removal of COD was similar in both systems. The nitrification rate for system in which raw sewage was exposed to magnetic field was lower than the system in which it was not.

The paper presents the results of studies on the changes in the PAHs concentration during pre-filtration and ultrafiltration (UF) processes. In the study, biologically treated wastewater (after denitrification and nitrification processes), discharged from the biological treatment plant and used in coke plant, was used. A gas chromatography-mass spectrometry (GC-MS) was used in order to qualify and quantify the PAHs. Sixteen PAHs listed by EPA were determined. The wastewater samples were collected three fold and initially characterized for the concentration of nitrate nitrogen, ammonium nitrogen, COD, TOC and pH. In the first step, wastewater was filtrated on the sand bed. Total concentration of 16 PAHs in the treated wastewater before initial filtration was in the range of 44.8‒53.5 mg/L. During the process the decrease in the concentration of the most studied hydrocarbons was observed. Concentration of PAHs after initial filtration ranged from 21.9 to 38.3 μg/L. After the initial filtration process the wastewater flew to the ultrafiltration module and then was separated on the membrane (type ZW-10). The total concentration of 16 PAHs in the process of ultrafiltration was in the range of 8.9‒19.3 mg/L. The efficiency of removal of PAHs from coke wastewater in the process of ultrafiltration equaled 66.6%. Taking into account the initial filtration, the total degree of removal of PAHs reached 85%. The obtained results indicate the possibility of using the ultrafiltration process with the initial filtration as additional process in the coke wastewater treatment.

The aim of the study was to determine the impact of various methods of oil mixing with wastewater on

properties of synthetic municipal wastewater containing edible oil (SMW+0.02% m/v rapeseed oil). The study was

carried out in 3L glass, cylindrical reactors to which SMW+0.02% were introduced. Various methods of its mixing

with water were applied: mechanical mixing (SMW+0.02%+mixing) and sonication (SMW+0.02%+ultrasounds).

The wastewater was sonicated at 35 kHz for 30 min. The constant temperature conditions were maintained during

the experiment for each mixing method (15°C, 20°C and 30°C). The analysis of parameters (pH, COD, BOD5

and

long chain free fatty acids concentration) of raw wastewater and after 2, 4, 6, 24, 48 and 72 hours of inoculation

was performed to determine the effect of mixing method.

The most signifi cant changes in wastewater chemical parameters after the introduction of the oil were observed

in the case of COD. For SMW+0.02%+ mixing a slow increase in COD within 24 hours of the process was observed.

In the case of SMW+0.02%+ultrasounds the increase and the decrease of COD value were observed in reference

to the initial value. The changes in acids concentrations observed in reactors with SMW+0.02%+ultrasounds were

referred to the ones observed in reactors with SMW+0.02%+mixing but changes were more intense in the fi rst

reactor. The use of ultrasounds in pre-treatment of wastewater resulted in the intense appearance of palmitic acid

for 6 hours. Regardless of the emulsion formation method (mixing or ultrasounds), the concentration of oleic acid

and linoleic acid was reduced. The biggest changes in free fatty acids concentration were observed for palmitic,

oleic and linoleic acids after 24 hours.

In the paper toxicity assessment of hospital wastewaters samples was performed using direct-contact

tests consisting of five species, which represent three different trophic levels of the food chain. IC50 or EC50 values were estimated for each tested organism: Pseudokirchneriella subcapitata IC50/72h 18.77%, Daphnia magna

EC50/48h 20.76%, Thamnocephalus platyurus EC50/24h 22.62%, Artemia salina EC50/24h 59.87% and Vibrio fisheri

EC50/15min 46.17%. Toxic potential of hospital wastewater was described using a system of wastewater toxicity

classification. The toxic units (TU) values estimated for each test indicate that hospital wastewaters are toxic

(Class III). The variable results of the tests’ sensitivity confirmed the need of application of microbiotests battery with organisms of different trophic levels.

Sewage and solid waste can be a valuable source of materials used directly or indirectly in manufacturing of usable products. These processes are associated with elimination of pollutants from liquid and

solid wastes. The best-known methods of waste management are production of biogas and composting. This

paper focuses on the possibility of obtaining biomass as a source of protein feed (whose value, in terms of the

composition of aminoacids and microelements, is comparable with conventional feed, e.g. soymeal, bonemeal

or fishmeal). Sewage components for bacterial, fungal, algal and vascular plants’ culture are characterized as

a source of protein feed. Methods of industrial scale production of enzymes, mainly proteases and lipases that

have broad applications in various industries, are discussed. Development perspectives of inexpensive methods

of usable products from waste production are showed. Interdisciplinary nature of presented issues, which requires cooperation of specialists in biology, chemistry and technology, is emphasized.

Biochemical Oxygen Demand (BOD) is an important factor used to measure water pollution. This article reviews recent developments of microbial biosensors with respect to their applications for low BOD estimation. Four main methods to measure BOD using a biosensor are described: microbial fuel cells, optical methods, oxygen electrode based methods and mediator-based methods. Each of them is based on different principles, thus a different approach is required to improve the limit of detection. A proper choice of microorganisms used in the biosensor construction and/or sample pre-treatment processes is also essential to improve the BOD lower detection limit.

The objective of this experimental study was to examine whether an assisting layer of lightweight expanded clay aggregate (LECA) of the granulation 1–4 mm, introduced into a subsoil, is able to improve an efficiency of removal of total nitrogen and total phosphorus from domestic wastewater. In the investigations, an assisting 0.10 and 0.20 m thick LECA layer was applied. It has been observed that the effectiveness of removal of total suspended solids (TSS), total nitrogen and total phosphorus from wastewater as well as the level of biochemical oxygen demand ( BOD ₅) and chemical oxygen demand ( COD) is in accordance with the Polish standards on wastewater disposal into grounds and surface water. The performed experiments showed that the effectiveness of raw wastewater purification for the medium sand soil bed with the 0.20 m thick assisting LECA layer is higher than for the 0.10 m thick assisting layer. In the medium sand soil bed with the 0.20 m thick assisting LECA layer, the removal efficiency regarding total nitrogen increased by 20.6%, total phosphorus by 5.2%, ammonium nitrogen by 8.8% and TSS by 5.3%, and reduction efficiency regarding BOD ₅ increased by 1.7% and COD by 2.3% with relation to the 0.10 m thick assisting LECA layer (all percentages – in average). The results of the experiment showed that the LECA with the granulation 1–4 mm can be used to assist in removal of total nitrogen and total phosphorus from wastewater with application of infiltration drainage.

The paper presents results of a study concerning ammonium and nitratc(V) fixation by soil irrigated with municipal wastcwatcrs ( 1 - 60 mm and 2 doses - 120 mm) and estimation or the possibility or using organic soil and grass-mixture for the wastewater treatment. It was found that the studied soil and the plant applied showed a very high capacity or binding ammonium ions (up to 96%), and lower in the case ofnitrates(V) (up to 71 %). It was also demonstrated that the single irrigation dose was better utilized compared to the double dose.