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 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 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.

This article describes monitoring results of raw wastewater from one Polish municipal wastewater treatment plant (WWTP). The residues of 30 pharmaceutics belonging to particular drugs classes such as contrast media. antibiotics, lipids regulators, antiphologisties, psychiatric and anticpilcptic agents, drug's metabolites and 2 musk compounds have been investigated. The investigation showed occurrence of 20 out of 32 selected compounds above their limit of detection. Iopromide, a compound belonging to contrast media, was noticed at the highest concentration. The concentration of this compound in WWTP-influent was equaled to 27.0 μg/dm3• Other drugs, such as, like iopamidol, iomeprol, diatrizoat, iohexol, sulfomethoxazole, carbamazepine, ibuprofen, ibuprofen-OH, naproxen, diclofenac, bczafibrate, ketoprofen, and musk compound - galaxolide were detected at maximum concentration between I .O μg/dm3 (bezafibratc) and 13.0 μg/dm3 (iomcprol). The acidic compounds such as gemfibrozil and indomethacin were determined above their limit of detection, with concentration up to 0.22 μg/dm3 and 0.42 ug/dm', respectively. Based on the literature data, the above-mentioned drugs arc not completely removed from sewage during treatment processes and with effluent from WWTP they are introduced to receiving waters. Due to their chemical properties, residues of pharmaceutics may persist in the environment and the present knowledge about their ccotoxicological effects is insufficient.

Surface wastewater pollution due to accidental runoff or release of oil or its products is a longstanding and common environmental problem. The aim of the study was to investigate the impact of concentrations of oil products (diesel) and suspended solids, the sorbent type, the water flow rate and the interfering factors (chlorides) on the dynamic sorption of diesel and to test regeneration of polypropylene after its use for sorption. The sorbents used for study included common wheat straw (Triticum aestivum), polypropylene and sorbents modified with hydrogen peroxide solution. Standard methods were used for the determination of the investigated parameters and an in-house procedure employing a gas chromatograph was used for the determination of diesel concentration. The following factors that impact the sorption of diesel were investigated during the study: diesel concentration, concentration of suspended solids; type of sorbent (common wheat straw (Triticum aestivum), wheat straw modified with hydrogen peroxide, and polypropylene), water flow rate; and influence of the interfering factors (chlorides). Filtration speed in the range of investigated speeds does not affect the efficiency of diesel removal. Removal efficiency does not depend on the concentration of diesel before the sorbent reaches its maximum sorption capacity. Filling containing 50% of polypropylene and 50% of wheat straw was used for the study. It was found that polypropylene and wheat straw do not remove chlorides and suspended solids from solution. The study found that the solution of hydrogen peroxide boosts the hydrophobic properties of common wheat straw, but does not affect the sorption of diesel. The recommended number of regenerations of polypropylene should be limited to two.

Two different porous ceramic carriers with immobilized activated sludge comprised a stationary filling of the reactors. Municipal wastewater was treated at hydraulic retention times from 15 to 70 min and internal circulation capacity of 20, 40 and 60 drn':h'. Depending on hydraulic retention time, the sludge yield ranged from 0.138 to 0.066 g TSS·g COD·' in reactor I and from 0.175 to 0.107 g TSS·g COD·' in reactor li. An increase in volumetric loading rate and internal circulation capacity caused a reduction in sludge yield. A decrease in the sludge yield corresponded to an increase in the ratio of endogenous to substrate respiration by the immobilized biomass

The present work focuses on problems connected with the location and sampling method for pecton (biofilm) in sewage treatment plants. We also discuss the amount and quantity of pecton necessary to compose a representative sample. Comparisons of other selected contamination indicators in place of pecton sampling, are also presented. Research carried out at the WWTP "Hajdow" demonstrated that everything (starting from grid chambers), coming into contact with sewage surfaces is covered with biofilm This biological formation does not cause any significant changes in sewage quality due to its relatively small surface compared to the sewage flux. As presented in the following analysis, pecton can be used for bioindication of sewage quality. This is possible because the organisms forming these communities use substances contained in flowing sewage as nutritional substrates. In such cases the wastewater purification level in biological sewage treatment plants can, in a way similar to rivers, be determined based on bioindication methods using existing similarities between the prevailing processes and organisms.

In environmental matrices there are mixtures of parent drug and its metabolites. The majority of research is focused on the biological activity and toxic effect of diclofenac (DCF), there is little research on the biological activity of DCF metabolites and their mixtures. The study focused on the assessment of the biological impact of DCF, its metabolites 4’-hydroxydiclofenac (4’-OHDCF) and 5-hydroxydiclofenac (5-OHDCF) and their mixtures on E. coli strains. The biological effects of tested chemicals were evaluated using the following: E. coli K-12 cells viability assay, the inhibition of bacteria culture growth, ROS (reactive oxygene species) generation and glutathione (GSH) content estimation. Moreover, we examined the influence of the mixture of DCF with caffeic acid (CA) on E. coli cells viability. Our results showed the strongest impact of the mixtures of DCF with 4’-OHDCF and 5-OHDCF on E. coli SM biosensor strains in comparison to parent chemicals. Similar results were obtained in viability test, where we noticed the highest reduction in E. coli cell viability after bacteria incubation with the mixtures of DCF with 4’-OHDCF and 5-OHDCF. Similarly, these mixtures strongly inhibited the growth of E. coli culture. We also found synergistic effect of caffeic acid in combination with DCF on E. coli cells viability. After bacteria treatment with the mixture of DCF and its metabolites we also noted the strongest amount of ROS generation and GSH depletion in E. coli culture. It suggests that oxidative stress is the most important mechanism underlying the activity of DCF and its metabolites.

In recent years, the technical and economic feasibility of using microalgae and cyanobacteria has been explored for the removal and exploitation of domestic, agricultural and industrial residual effluents with high C, N and P compounds content. To contribute to the understanding of the process and its technical viability for microalgae growth, the article discusses monitoring, flow determination, and physicochemical characteristics of two types of effluents generated in an experimental farm located in the east of Colombia, before (R1) and after biological treatment (R2). In general, the results showed the reduction of different parameters, such as total dissolved solids (TDS), hardness, salinity and phosphates after treatment with activated sludge. However, the conductivity value obtained in R1 and R2 showed the presence of a pollutant load. These findings can be attributed to the highest concentration of fats and oils in the water during early hours of the day. Finally, although the concentration of nitrates increased from 46.63 to 225.21 mg∙dm–3 and phosphate decreased slightly from 9.65 to 6.21 mg∙dm–3, no inhibition was generated in the microalgae, as evidenced in the growth of the microalgal biomass in effluents after nitrate and phosphate removal above 80%.

The present study is aimed to access the growth rates, biomass productivity and nutrient removal in different concentrations of microalgae Botryococcus sp. beads using kitchen wastewater as a media. Verhulst logistic kinetic model was used to measure the optimal concentrations of microalgae Botryococcus sp. in kitchen wastewater in terms of cell growth rate kinetics and biomass productivity. The study verified that the maximum productivity was recorded with 1×106 cell/ml of the initial concentration of Botryococcus sp. with 42.64 mg/l/day and the highest removal of tp and ammonia was obtained (78.14% and 60.53% respectively). The highest specific growth rate of biomass at 0.2896 μmax/d compare to other concentrations, while the lowest occurred at concentrations of 105 cells/ml at 0.0412 μmax/d. The present study shows the different concentrations of Botryococcus sp. in alginate beads culturing in kitchen wastewater influence the cells growth of biomass and nutrient uptake with optimum concentration (106 cells/ml) of Botryococcus sp. which is suggested for wastewater treatment purposes. The result of scanning electron microscopy (sem) shows differences in morphology in terms of surface; smoother and cleaner (before the experiment), cracks and rough surface with black/white spots (after the experiment). These findings seemly can be applied efficiently in kitchen wastewater treatment as well as a production medium for microalgae biomass.

The anammox (anaerobic ammonia oxidation) process is one of the most efficient processes of nitrogen removal from wastewater. Although there are some applications of anammox-based technologies, it is still difficult to apply this process widely because of the high optimal temperature around 30–40°C. Thus, the main objective of this study was to evaluate the short-term effects of MnO ₂ on the anammox and nitrification process activity at a wide range of temperatures between 10 and 30°C, using statistical methods based on the central composite design (CCD). The influence of MnO ₂ on anammox and nitrification activity, suspended biomass from the laboratory-scale sequencing batch reactor (SBR), and activated sludge from WWTP, respectively, was used. MnO ₂ concentration range was set between 15 and 85 mg/L, and the temperature range was set between 10 and 30°C. Anammox and nitrification process activity was measured based on the batch test and oxygen uptake rate (OUR), respectively. The results were statistically analyzed. Results revealed that nanoparticles can slightly improve anammox activity by several percent, by up to 10%, but in most cases MnO ₂ influence was insignificant. The optimal concentration for the anammox stimulation at temperatures below 20°C was evaluated between 40 and 60 mg/L, corresponding to 36 and 56 mg/g VSS. Manganese oxides contribution in the nitrogen removal processes was proved and they should be considered in the field of the anammox process. Thus, further studies are suggested to investigate the long-term effects of MnO ₂ on the low-temperature anammox process, overcoming possibility of inhibition

This work aims to evaluate the treated wastewater from the activated sludge treatment plant in the City of Sidi Bel Ab-bes (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 char-acteristics of a good treated water quality for reuse in the field of irrigation while protecting the environment. The pedolo-gical 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.

The study has investigated the technical characteristics of a number of sorption materials (natural mineral) and the pos-sibility of their use for the purification of surface and wastewater from oil and oil products. At the first step, regularities of the process of purification of oily waters have been established taking into account the processes of filtration and sorption. After that, the sorption capacity of the sorbents has been estimated, and the factors influencing it analysed. As a final step, the optimal conditions for the sorption process have been selected depending on the conditions and nature of purification. Results indicated that the maximum purification degree has been reached at the concentration of 500 mg∙dm–3 and temper-ature of 20°С.

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 anaerobi-cally 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 pro-posed system will allow the reuse of 30% of the water used in the washing of fruits and vegetables.