Serhii Protsenko, Mykola Kizyeyev, Olga Novytska
et al.
The article analyzes the current state of the regulatory framework of Ukraine in the field of collection, transportation and treatment of wastewater, as well as the treatment of their sediments. It is revealed that the current regulatory system, despite some updates, is largely based on outdated approaches of the Soviet regulatory school (SNiP), which do not take into account modern technological, environmental and climatic realities. The key problems of the current regulatory framework are identified, which are associated with its obsolescence, fragmentation and inconsistency with modern European approaches and environmental challenges. The urgent relevance of developing a new package of regulatory documents is substantiated, which is due to Ukraine's obligations under the Association Agreement with the European Union, in particular the implementation of EU Council Directive 91/271/EEC, as well as the need to respond to modern environmental, energy and climatic challenges. Based on a comparative analysis with the regulatory documents of the EU, Germany, the Netherlands, Switzerland and other countries, a new modular structure of national standards has been proposed, which includes the framework State Building Codes (DBN), harmonized State Standards of Ukraine (DSTU) and separate Methodologies and Guidelines. Key innovative technologies and principles (energy efficiency, circular economy, removal of micropollutants, digitalization, climate adaptation, etc.) have been identified, which should be integrated into the new regulatory framework for the sustainable development of the industry. It has been concluded that the development of a new package of regulatory documents based on European principles is a necessary condition for ensuring environmental safety and public health, creating a legal framework for the application of advanced technologies and investments, effective integration of Ukraine into the Single European Market, and building a sustainable and renewable water drainage system. The implementation of this reform will require consolidated efforts of the authorities, science, business and the public.
Cyanide ion is highly toxic to human. Cyanide ion is mainly used in processes like electroplating and extraction of silver and gold. Therefore, it can enter the environment and pollute soil and water. In the present work, a colorimetric method based on silver nanoparticle (AgNP) was proposed for detection and determination of cyanide ion. Silver nanoparticle was prepared by carbon dots as reducing agent. Volume of AgNP and concentration of sodium hydroxide were optimized for determination of cyanide ion by AgNP. It was observed that greenly synthesized AgNP can serve as reagent in detection and determination of cyanide ion. In the presence of sodium hydroxide, a method was optimized and a robust model with linear range of 4.0-100.0 μM, limit of detection of 3.8 μM and limit of quantification of 12.7 μM was obtained. In the method presented, the color change of AgNP from yellow to colorless in the presence of cyanide ion was observed. Environmental water samples including spring, well and wastewater were successfully analyzed by this method, which is simple and inexpensive.
Technology, Water supply for domestic and industrial purposes
Undoubtedly, the activated sludge process is one of the most common methods of biological wastewater treatment. Among the most common problems of activated sludge process systems is bulking of sludge (bulking). More than 50% of activated sludge wastewater treatment plants worldwide constantly or occasionally face this problem. In this case, the relative density of the flocs is low. It causes inappropriate sedimentation in secondary ponds and causes problems such as reducing treatment efficiency and imposing additional costs in the treatment and disposal of excess activated sludge. The current study, which was carried out on a laboratory scale (pilot) in the refinery unit of Shahid Tondgoyan Petrochemical Company, to investigate the factors affecting the creation of bulking. Factors include process parameters such as adjusting the ratio of input feed to microorganism (F/M), microorganism concentration, supply of nitrogen and phosphorus nutrients, dissolved oxygen, temperature, pH, and the use of cationic polyelectrolyte coagulant to improve the sedimentation rate of activated sludge. The optimal parameters in the amount of sedimentation are F/M equal to 0.35, MLSS in the range of ppm 2500 to 3000 ppm, nitrogen, and phosphorus nutrients relative to the amount of pollution (COD/N/P) in the range of 100/4/1 until 100/5/1, dissolved oxygen 2 to 3 mg/L, temperature 25-35 °C, pH range 8.5 and in the dose of 4.8 mg/gr TSS/L of cationic polyelectrolyte coagulant in 180 min. In general, by adjusting the process parameters in the indicated range, the amount of SVI can be controlled in the desired range of close to 150 mg/L.
Technology, Water supply for domestic and industrial purposes
Hamid Heydari, Aptin Rahnavard, Farid Gholamreza Fahimi
et al.
Wastewaters containing heavy metals produced by industries has detrimental effects on the environment. One of the effective methods for removal of heavy metals is the use of adsorption method by nanoparticles. The aim of this study was to remove zinc and nickel elements from effluents of Tarom industrial Town of Zanjan using modified multi-walled carbon nanotubes. In this descriptive-analytical study, effect of effective parameters such as contact time, adsorbent content, pH, temperature and concentration of metal ions on the removal efficiency of metals from Ni(II) and Zn(II) from wastewater and isotherm, kinetics and thermodynamic models of adsorption process was investigated. SEM and FTIR spectrums were taken to prove nanotubes and to determine adsorbent factor groups before and after preparation, respectively. The results of study showed that the absorption of Zn and Ni metals is highly dependent on pH. Study results showed that by increasing the pH of effluent up to the range of 8, and 7 for Ni(II) and Zn(II) metals, respectively, the removal percentage of metal ions increased and then decreased. By increasing in the adsorbent amount and contact time, the removal percentage of metal ions increased and by increasing the reaction temperature and concentration of metal ions in the effluent, the removal percentage of metal ions decreased. So that, the highest removal percentage of Ni(II) and Zn(II) ions was obtained in adsorbent value of 2 mg/L, contact time of 120 min, concentration of 100 mg/L and temperature of 15 °C. The results also showed that the adsorption of Ni(II) and Zn(II) metals from effluent follows Langmir isotherm absorption model and the adsorption kinetics is adapted to the second-order pseudo-reaction (R2>0.98), this mechanism is controlled by adsorption. Also, based on the obtained results, with increasing temperature, the free energy of Gibbs system standard decreased, which indicates the adsorption process is done spontaneously. The maximum adsorption capacity of nickel and zinc metals was 43 and 54 mg/g, respectively. According to the results, it is concluded that modified multi-walled carbon nanotubes have good ability to remove nickel and zinc from effluents and can be used in wastewater treatment containing heavy metals.
Technology, Water supply for domestic and industrial purposes
Elahe Javadi, Majid Baghdadi, Lobat Taghavi
et al.
4-Nonylphenol (4-NP) as one of the most abundant and toxic alkylphenols is the most effective of endocrine disruptive compounds. It is produced in high quantities and then enters the aquatic environment via discharge of sewage treatment effluents. Therefore, its removal from surface water and municipal wastewater effluents is more commonly considered. This study has been done with the aim of the investigation of the grapheneoxide chitosan aerogel beads’ performance for removal of 4-NP from aquatic solutions. In this regard, the characteristics of the synthesized nano-adsorbent have been investigated by SEM, TEM, FTIR, BET and pHpzc techniques. Then, batch adsorption experiments have been done to determine the adsorption behavior. In this method, the effect of some parameters such as adsorbent dosage, 4-NP concentration, pH, contact time, and temperature was evaluated with the aim of determining optimum conditions. The results show that the adsorption efficiency could reach 100% in 10 min at neutral pH with 1.5 mg/L of 4-NP concentration and 0.8 g/L of the adsorbent. The achieved results were compared with different kinetic and isotherm models, which found that the 4-NP adsorption by the synthesized nano-adsorbent are explained by the Pseudo-Second-Order kinetic (R2=0.9992) and Dubinin-Radushkevich isotherm (R2=0.9988) models with the adsorbents’ maximum capacity of 70.97 mg/g. Thermodynamic investigations indicated that the adsorption process was spontaneous and feasible (-ΔG), endothermic (+ΔH), and reversible (+ΔS).
Technology, Water supply for domestic and industrial purposes
Microplastics have raised many concerns because of their potential negative impacts on the environment. Identifying the sources of microplastics release to the environment is a challenging subject. Synthetic textiles, such as machine woven carpets, are highly capable to propagate and emit microplastics, especially fibers. While the carpet cleaning service has experienced a fast growth due to urbanization and its impact on life style, there is a lack of information on the number and the size of fibers, which are released during the washing process. In this study, we characterized the microplastic fibers in the wastewater of two carpet-washing workshops in the cities of Ahwaz and Sari in Iran. Three replicates of 10 L-samples were taken from the wastewater of washing and drying stages. All samples were passed through sieves of 500, 300 and 37 μm. The residues were washed with 1 L distilled water and poured into clean glass bottles. Then, the samples were passed through 25 μm filter paper. The remained materials on the filter were examined using a stereo microscope. Shapiro-Wilk and Levin tests were applied to test the normality and homogeneity of data. One-way ANOVA test was used to investigate the differences in size of microplastic fibers and independent t-test to determine the difference between the total number of the released microplastic fibers and the ones at each stage in the cities. More than 3097 and 1824 microplastic fibers per square meter of carpet (equal to 81 and 48 microplastic fibers per liter of wastewater) were counted in the workshops in Ahwaz and Sari, respectively. The shares of microplastic fibers in the size of ≥500, 300-500 and 37-300 μm were 18.4%, 24.6%, 57% in Ahwaz and 14.4%, 28.8%, 56.8% in Sari, respectively. The number of released microplastic fibers per liter of wastewater of carpet washing workshops is much higher than the number of fibers in the raw wastewater entering Sari WWTP, which was 4.9-12 microplastic fibers per liter. The washing of machine woven carpets is an important emission source of microplastic fibers especially with the size of less than 300 micron. The number of released microplastic fibers depends on the type of washing and drying practices. It is expected its emission load will sharply increase in future due to the booming growth in demand for these kinds of reasonably priced floor covers.
Technology, Water supply for domestic and industrial purposes
Abstract In the process of urbanization, each city should actively respond to the call of the country and regard sustainable development as the core of development. Based on this, cities should pay attention to urban environment and ecological benefits. In cities, urban sewage plants should pay more attention to sludge treatment and disposal. Through strict sludge treatment, the impact of heavy metals and pathogens in the sludge on the urban environment will be reduced. Based on the continuous updating of sludge treatment technology and processing equipment in China, urban sewage plants must strengthen the rational disposal of sludge. In order to improve the efficiency of sludge disposal and avoid pollution to the environment, it is particularly important to do a good job in sludge treatment status and technology research. Briefly analyse the source and nature of sludge in urban sewage treatment and the status of sludge treatment and disposal, and focus on the relevant sludge treatment technology to provide reference for better application of sludge treatment technology.
Nitrate and phosphate are of specific importance among different water pollutants due to their effect on aquatic ecosystems and disrupting their balance. The electrocoagulation process has been recognized as a novel method that has recently been employed for the removal of nitrate and phosphate. Therefore, the present study was aimed at investigating the efficiency of simultaneous removal of nitrate and phosphate from water through an electrical coagulation process. This experimental study was performed with an experimental scale as a pilot. The pilot was made of Plexiglas with the volume of 5.4 liters associated with a DC power supply. Parameters of the reaction time (5-90 min), pH of water (3-9), the concentration of nitrate and phosphate (1-50 mg/l), electrode materials (iron, aluminum, and steel), the distance between electrodes (1-10 cm), and the current's voltage (5-40 V) have been investigated in this research. The effect of each parameter was also examined on the amount of nitrate and phosphate removal. Obtained results were then analyzed to determine the efficiency of nitrate and phosphate removal in the form of comparable diagrams. Results of current experiments represented the optimal parameters including the reaction time of 60 min, pH of 7, initial concentration of 10 mg/l, electrodes of iron-iron, with the distance of 5 cm, and input voltage of 30 V. The removal efficiency of nitrate and phosphate under optimal condition was reported 95 and 45%, respectively, as the maximum removal rates. The present study has introduced the electrocoagulation process as a reliable and flexible way to purify water resources from nitrate and phosphate.
Technology, Water supply for domestic and industrial purposes
Water distribution network one of the most important and most sensitive urban infrastructures which can be recently with regard to population growth and consumers '' needs to increase with challenges such as reducing the pressure and discharge that are all due to unsuitable design and based on economic goals. In order to overcome these problems when designing an urban water distribution system should always be considered reliability of the network. In this research, to optimize the water distribution networks, two main objectives of cost minimization and maximization of network reliability were considered. To calculate network reliability, the Tondini''s Resilience Index and its hydraulic simulation EPANET 2.0 model were used. Then using the second edition of the evolutionary algorithm based on the strength of the Pareto (SPEA2) and creating a dynamic connection with the EPANET 2.0 hydraulic model in the MATLAB software environment, optimizing the multi-objective of the four water distribution networks including Two-Loop, Kadu, Hanoi networks and D zone of Mashhad. Simultaneous optimization of two main objectives including cost minimization and maximization of the Tondini''s Resilience Index led to the production of optimal solutions in the form of the Pareto front. An optimal solution, called Point C, was introduced using Young''s bargaining method from the final Pareto front of in each of the networks. Selected C solution in two-loop,Hanoi and Kadu networks increased 22.91, 17.13 and 7.41 precent, of the network average pressure compared to its lowest cost in this study (point A). Also, the selected C solution in D-zone network of Mashhad, with an increase of 4.23 precent of the network average pressure compared to the initial design of the consulting company (point D), illustrate that the solution designed by the consulting company would be a dominated solution under the final Pareto front of this study. In this research, the Tondini''s Resilience Index illustrate that, based on increasing nodal pressure, it has the ability to increase the reliability of the network, which This causes the network to be in critical condition or failure of the pipes, with high reliability, providing adequate pressure and discharge in other nodes. Also, the satisfactory performance of the SPEA2 multi-objective algorithm in providing the optimal Pareto front for the issues indicated showed that the design pattern developed in this study could be to provide an optimal set of solutions to the employer to select the points in which each two factors of cost and reliability are combined in a favorable situation.
Technology, Water supply for domestic and industrial purposes
Mohammad Attari, Abbas Khashei Siuki, Saeed Asgharzadeh manzari
et al.
Water Pipe Line are the lines that take water from different resources and transfer it to drinking needed nodes, industry or agriculture. Because of the intense shortage of water resources especially in the eastern and central reigns of our country, in the recent years some plans have been proposed for water transferring among basins. These projects not only have led to a lot of social conflict in the area that these project have been done but also causes some subversive acts along the pipe lines and dependent installation. So finding suitable location for pipe lines from the passive defense point of view will be very important. In this research a method for finding suitable location for great pipe lines according to different criteria such as privacy, access, military, economic, population, geology, geomorphology, climate and hydrology is introduced. Each criteria is classified to several subgroups. So all the subgroups are done quantification in software of Arc-GIS9.3. Then with super position of above layers, the planed area and high risk places are coloured and determinedon the map. The results shows that the route which has the best access and the least intersection with Faults, agricultural areas, rivers and gas pipe lines with 374 kilometers lengths are selected as the best options.
Technology, Water supply for domestic and industrial purposes
Mehdi Hosseinifard, Hadi Ghorbani, mostafa aghazadeh
et al.
Removal of copper from aqueous solutions was investigated using manganese dioxide nanoparticles as a new and suitable adsorbent. For this purpose, manganese dioxide nanoparticles were synthesized using the cathode electrochemical deposition method and the effects of pH, contact time, MnO2 concentration, and copper concentration on copper removal efficiency were investigated in a batch system. Scanning electron microscope (SEM), XRD, and FTIR were used to characterize the synthesized manganese dioxide nanoparticles. Results showed that nanoparticle diameters ranged from 30 to 50 nm and that a copper adsorption efficiency of bove 96% percent would be achieved at an optimum pH of 7. It was found that increasing the copper concentration and reducing adsorbent dosage led to enhancements in adsorption capacity but slight reductions in adsorption efficiency. Experimental data also indicated that copper adsorption fitted the Freundlich model with an adsorption capacity of above 169 mg.g‒1 and that it obeyed a pseudo-second order kinetic equation. It was concluded that manganese dioxide nanoparticles may be used as a suitable adsorbent with a high potential for the removal of copper from aqueous solutions.
Technology, Water supply for domestic and industrial purposes
Farahnaz Sabet, Mojtaba Bandegani, Mehraban Sadeghi
et al.
Maharloo Lake is one of the most important water ecosystems in Iran, which is nowadays exposed to multiple risks and threats due to poor water management, salt extraction, and heavy metal pollution. In this study, the concentrations of such heavy metals as chromium, copper, zinc, arsenic, cadmium, and lead in both water and salt samples collected from areas in the north and south of the lake were determined by atomic absorption (AA-670G) after the samples had been digested. Results showed that metal concentrations in the salt samples taken from both the northern and southern areas had identical mean values in the order of Cr> Cu> As> Cd> Pb. An almost similar pattern was detected in metal concentrations in water samples taken from the same areas but with a slight difference in the way they were ordered (Cr> Cu> As> Pb> Cd). It was found that both water and salt samples collected from the northern areas had higher metal concentrations, except for that of Pb which was slightly lower. Comparison of the mean values of metal concentrations in the Salt Lake and those of Sirjan, Lar, and Firoozabad salt mines revealed that copper, cadmium, and lead had their highest concentrations in the Salt Lake while arsenic and chromium recorded their highest values in samples taken from Lar and Firoozabad salt mines, respectively. Based on these findings, it may be concluded that the increased metal concentrations observed in samples from both northern and southern areas of the lake are due to the sewage and effluents from urban, industrial, and hospital sources in Shiraz disposed into the lake as well as such other human activities as farming in the areas around the lake, especially in the northern stretches. These observations call for preventive measures to avoid further water quality degradation in the area.
Technology, Water supply for domestic and industrial purposes
Ahmad Jonidi Jafari, Roshanak Rezaei kalantari, babak kakavandi
et al.
In this study powder activated carbon (PAC) and Fe3O4 magnetic nanoparticles were combined by using co-precipitation method to preparation of magnetic nanoparticles Fe3O4-activated carbon (Fe3O4-AC MNPs) as an adsorbent for removal of aniline from wastewater. Physical characteristic properties of adsorbent were analyzed by SEM, TEM, XRD and BET. Also, the effect of various parameters such as pH, contact time, adsorbent dosage, initial aniline concentration and solution temperature were investigated. The experimental data considered by Langmuir and Freundlich adsorption isotherms and two models kinetically of pseudo first-order and pseudo second-order. The results showed that the adsorption followed Langmuir and pseudo second-order models. According to Langmuir isotherm, the maximum adsorption capacity was 90.91 mg/g at pH 6, and adsorbent (magnetic activated carbon) due to have advantages such as easy and rapid separation from solution could be applied as an effective and useful adsorbent for removal of pollutants from water and wastewater.
Technology, Water supply for domestic and industrial purposes
Flooding and its damages are not only found uplift water level in a region. In other words, the depth and speed parameters together have determining the level of flood risk at each point. This subject is visible in flooded plain with low height and high speed of 2 meters per second, which damages are extensive. According to the criteria of having both velocity and flow depth in the governing equation to the flows energy, this equation seems appropriate to analysis in this study. Various methods have been proposed for increase accuracy in flood zoning with different return periods and risks associated with it in land border of river. For example, some of these methods are considered factors such as analysis of past flooding in the area affected by floods, hydrological factors and consideration of hydraulic elements affecting in flood zoning (such as flow velocity). This paper investigates the effect of flood zoning by the energy flow in the areas affected by floods. Also risk due to flood based on energy flow in each section of the river is compared by the proposed graphs of hazard interval and other done flood zoning in this field. In this study, the FORDO river has been selected as the case study. This river is part of the rivers located in the city of QOM KAHAK. The characteristics of river in upstream and downstream are mountain, young and stable and adult, respectively. Also this river in different seasons is exposed the flood damage. The proposed method in this study can be improving recognition accuracy of flood risk in areas affected by flood. Also, this method facilitate the identify parts of the river bed, that is affected by severe flooding, for decision making to improve rivers organizing.
Technology, Water supply for domestic and industrial purposes
There are many non-wood lignocelluloses resources such as wheat, rice straw and other agriculture by- products with appropriate feature for pulp production in Iran. The most major deterrent to their use is presence of pulping black liquor that due to lignin of lignocelluloses solution contains significant amounts of color and phenol compounds. The aim of this paper was investigation of the ability to remove phenol and color as the most important organic pollutants from back liquor of agri-based pulping process using electrocoagulation method. In the electrocoagulation process aluminium electrode was used and cell potential and current intensity were adjusted on 16 V and 1700 mA respectively. The effect of various treatment time (10, 25, 40, 55, 70 min) and initial pH (3, 5, 7, 9, 10/5) of black liquor were investigated.The results showed that maximum of decrease obtained at pH 5 that has led to a remove capacity 78% of phenol and 98% of color in treatment time 70 min. electrocoagulation method can be used for black liquor treatment because of simple, effective and its low investment cost compared to other technologies.
Technology, Water supply for domestic and industrial purposes
Mohsen Nasseri, Masoud Tajrishy, Mohammad reza Nikoo
et al.
Methods for evaluatingthe quality of groundwater resources and recognition of appropriate locations for urban and agricultural water demand has been known as an important item in water resources planning. The main focus of this paper has been addressed a new water quality mapping based on coupling of fuzzy approximation and water quality indexing. In this paper, after indexing water quality in each monitoring well, based on fuzzy reasoning a new global fuzzy indexing has been presented. In this regard, 12 water quality parameters for 217 monitoring wells in the province of Ghazvin in the north have been used. In the final step, map of fuzzy evaluation over the area of interest has been provided based on an optimized new spatial approximation via Genetic Algorithm (GA). The results showed the capability of the proposed methodology for groundwater quality mapping. The most important contribution of this paper is successful combination of fuzzy reasoning and water quality indexing as a continuous function for evaluating groundwater quality mapping.
Technology, Water supply for domestic and industrial purposes
Mohammad Ali Falahi, Hossein Ansari, Saiedeh Moghaddas
The increasing trend of water demand is an inevitable problem all over the world. Considering the population growth, industry development, improvement of sanitation level and public welfare, renewable resources per capita like water is decreasing. In this paper, water demand is derived using Stone-Geary function and it is estimated using the random effects model. The used data is panel and yearly and is related to 266 household during 1382-1386 in Neishabour.Water demand is estimated using average price, income per capita, price index of goods and services and average temperature variables. The price elasticity is -0.15, income elasticity is 0.15 and cross-elasticity is -0.00025. It is shown that water demand has low elasticity with respect to income and price and it is complementary with other goods. Furthermore, the average temperature is not significant. Three scenarios are used to forecast water consumption. The results show that if the price of water does not increase, the water consumption per capita of household will increase with increase of income per capita. Also an increase in tariffs will decrease the per capita water consumption household.
Technology, Water supply for domestic and industrial purposes