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 It is revealed that the current regulatory system, despite some updates, is largely based on outdated approaches of the Soviet regulatory school (SNiP), which do not take into account modern technological, environmental and climatic realities.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.
Abstract Cationic Blue GRL, BB 41 dye, caused more toxic harm to sewage when it was utilized to dye and print textiles. Dopant (TiO2 doped with Ag) nano-specimens were prepared with different Ag (0.01, 0.03, 0.05, and 0.07 mol%) by effectively utilizing a preliminary humid impregnation. The diffuse reflectance spectroscopy spectrum's surface plasmon resonance feature confirmed the amount of Ti4+, and Ag+ charged particles was significantly diminished. The undoped TiO2 and TiO2 doped with Ag nanoparticles characterized by Scanning electron microscope (SEM), Transmission electron microscope (TEM), High-resolution transmission electron microscope (HRTEM), Energy Dispersive X-ray (EDX), X-ray diffraction (XRD), Nitrogen (N2) adsorption-desorption evaluates, and the band gap structure (GGA+U calculations). Several impacts encompassing pH, duration of contact, original BB 41 instances, the level of H2O2, temperatures, and the amount of TiO2 doped with Ag nanomaterial photocatalyst influence the photodegradation efficiency percent and the rate of degradation for BB 41. The kinetics of adsorption developed as four rates (Pseudo-first, Pseudo-second, Intra-particle diffusion, and Elovich) at various original BB 41 instances were investigated. Compared to these calculations, Pseudo-first was more effective, indicating a potential physisorption mechanism for the adsorption. The adsorption developed by the three isotherms examined (Langmuir, Freundlich, and Temkin) for the BB 41 adsorption. Compared to these calculations, Langmuir's equation matched more effectively. The disc diffusion test was used to measure the antimicrobial activity of undoped TiO2 and various amounts of Ag-doped TiO2 nanoparticles. These bacteria included a pair of gram-positive (Bacillus subtilis and Staphylococcus aureus), and one gram-negative (Escherichia coli). Furthermore, the reusability and regeneration of Ag-doped TiO2 nanoparticles under ultraviolet (UV) radiation was demonstrated.
It is more important to improve and complete the wastewater process in order to reuse and return it to the production line. In this study, the hydrogen peroxide/ozone process (Peroxone) was investigated as a supplementary step in paper mill wastewater treatment to reduce the amount of chemical oxygen demand and remove E. coli. In this regard, using the Box-Behnken Design method based on the response surface method to optimize and investigate the effect of three variables governing the ozonation process, including the amount of hydrogen peroxide consumed (ml), the amount of ozone input (mg/min) and ozonation time (min) were used. The results showed that the amount of ozone and hydrogen peroxide had the greatest effect for reducing COD (up to about 75%). Also, all three variables have played a significant role in increasing the efficiency of the Peroxone process and even completely eliminating E. coli. In determining the optimal conditions, the amount of ozone (146 mg/min), the amount of hydrogen peroxide (2ml) and the duration of ozonation (23 min), the lowest amount of residual COD (73 mg/L) and the highest efficiency (75% removal of E. coli) are predicted. The results showed that due to the interaction of ozone and hydrogen peroxide, the peroxone process performance was less efficient than the ozonation process alone.
Technology, Water supply for domestic and industrial purposes
Sara Nikmaram, Golamreza Nabi Bidhendi, Naser Mehrdadi
et al.
In Iran, little attention has been paied to the nexus of energy and carbon footprint in wastewater treatment plants. The main goal of the current research is to investigate this issue in a municipal wastewater treatment plant with a conventional activated sludge (conventional). While studying the quantity and quality of wastewater, direct and indirect emissions were calculated based on the operation of the treatment plant and the amount of electricity consumption using emission coefficients. An average of 6,192,000 m3 of wastewater is treated annually in this treatment plant. The average BOD5 and COD removed are 274.6 and 467.9 mg/L, respectively. On average, 0.3623 ± 0.081 kWh/m3 of energy is consumed for treated wastewater, which is equivalent to 2241.5 MWh per year. As much as 94.6% of energy is consumed by pumps and surface aerators. Considering BOD removed, the direct greenhouse gas emissions are on average 2338.2 tCO2e/year and the indirect emissions due to electricity consumption are 2603 to 4665 tCO2e/year. Old design and lack of up-to-date equipment are factors that increase energy consumption and carbon footprint emission. The low tariff of electricity in the wastewater treatment plant (agricultural tariff) has made the issue of saving energy consumption less of a priority. It is necessary to pay attention to the reduction of electricity consumption, especially in the reactive mode, with the necessary modifications. It seems essential to conduct an energy audit in the existing treatment plants and pay attention to the nexus between energy and carbon footprint.
Technology, Water supply for domestic and industrial purposes
Plenty of methods have been introduced to treat the consumed water where the advantages and disadvantages of each method define their applications. Advanced oxidation processes have become a scientific trend due to high removal efficiency. As one of the AOP methods, heterogeneous Fenton method has received plenty of interest because of its high operational capability. In this study, cellulose/CuBDC/Fe3O4 nanocomposite was utilized as heterogeneous Fenton catalyst to remove Direct Blue 71 toxic dye from aqueous media. The catalyst was synthesized as granulated beads to eliminate the operational limitations of utilizing powdered catalysts. The catalysts were characterized by SEM, EDX, FTIR and XRD analysis to validate the successful synthesis procedure. The effects of each component of the nanocomposite on the removal efficiency were investigated. The effective operation of independent parameters such as the initial dye concentration, H2O2 concentration and catalyst dosage were modeled and optimized by RSM design of experiments method. At the optimum point, the removal efficiency of 86.93% was achieved. In addition, the COD of the wastewater was decreased by 73.52%, which demonstrated the high potential of granulated cellulose/CuBDC/Fe3O4 nanocomposite in decomposing organic matter to H2O, CO2, NO2 and SO2. The prepared granulated catalysts retain their removal characteristics over 8-cycle operation.
Technology, Water supply for domestic and industrial purposes
Contamination of drinking water is known as a major threat of water security around the world. As contamination enters a water distribution network, it spreads rapidly into the network and poses health and safety risks to the community. Using a set of sensors to report the concentration of chlorine or any other chemical, useful observations can be made to detect, identify and manage pollution. Based on these observations, location, concentration and start time of contamination can be determined and decision makers can be informed. In this paper, a simulation-optimization approach is used to solve the problem of contamination source characterization in which the EPANET software is used as a simulator and the Genetic Algorithm is used as an optimizer. The model developed in this paper is implemented on EPANET example 3. Modeling of water distribution networks uses information as input data which can cause error in model simulation. Pipe roughness and chlorine deterioration rate are among these inputs. The model has been implemented to find the location, start time and concentration of inlet pollution and the effect of pipe roughness and chlorine deterioration rate on the model responses have been investigated. The pollution entry scenario is applied to the network and the model presented is accurate in finding the location and time of the contamination. As the variables increase, the model accurately estimates the location and time of entry of the contamination but does not have complete accuracy in estimating the concentration of contamination, which is calculated with standard deviation of σ = 4.8% -8.1%.
Technology, Water supply for domestic and industrial purposes
Contamination of a water distribution network (WDN) is one of the most dangerous events which may occur in accidental or deliberate conditions. The contamination spreads across the network based on the water flow and, as a result, has negative consequences on public health. In this regard, one of the most effective strategies is to install quality sensors. These sensors could reduce the damage due to detecting the contamination and applying appropriate policies. In this study, an optimization approach for quality sensor placement is presented. In this model, based on spatial and temporal uncertainty of input contaminant, a new parameter called maximum possible damage is introduced. Using EPANET as a hydraulic and quality simulator, the damage matrices are calculated for all possible values of temporal and spatial input contamination. In the following, these matrices are used in an optimization model in order to calculate the maximum possible damage. The genetic algorithm is implemented here to solve the problem. The presented method is investigated on a case study network, and results show that this method could find the optimal sensor placement and reduce the damage caused by contamination. As an example, it can be seen that installing one or two sensors could reduce the contaminated water damage by 56% and 78%, respectively.
Technology, Water supply for domestic and industrial purposes
In many industrial processes, the acetone solvent is mixed with water in various proportions, and it is not possible to separate these mixtures without consuming a great deal of cost and energy. Nowadays, scientists are looking at some methods to separate solvents more efficiently without consuming too much energy. Therefore, given the importance of different solvent separation processes and their reuse in industry, in this research, for the first-time molecular dynamics simulation of water-acetone mixture separation using armchair carbon nanotube was performed. To separate the water-acetone mixture, the (5,5) and (6,6) armchair carbon nanotube was used so that these nanotubes acted as a separator filter for the water-acetone mixture. For this, we used molecular dynamics simulation method. Also, the hydrostatic pressure, as an external force, was applied to the desired system to separate water and acetone from each other with selectively passing them through the nanotubes. The results showed that by changing the type of the nanotube, the process of separating this mixture showed a different behavior; so that, this mixture was completely separated using the (5,5) carbon nanotube with small diameter, while in the presence of (6.6) carbon nanotube with large diameter, the separation was not complete and both solvents passed through this type of nanotube in different proportions, which was not desirable. To better understand the results and their interpretation, some analyses including the permeated water or acetone molecules through nanotubes, the density profile, the potential of the mean force, retention time, and hydrogen bonds of the system were also extracted. According to the results of the present study, armchair carbon nanotubes with suitable diameter can be used for separation of some aqueous mixtures, including water-acetone mixture, which will enable us to obtain pure species of each solvent, allowing them to be reused and save costs.
Technology, Water supply for domestic and industrial purposes
Mostafa Rahmanshahi, Manoocher Fathi-Moghadam, Ali Haghighi
Leakage in water transmission systems and distribution networks in addition to waste of water and energy, can cause a declined water quality due to exposure to contaminants at low pressure conditions as well as damages to roads, buildings, and infrastructures. Therefore and due to its negative impacts on economics, environmental, and social safety, determination and control of leakage is one of the most important and complex topics in water supply systems engineering. The current research investigated transient-based techniques for leak detection in Polyethylene water pipe systems. For this purpose, firstly an inverse transient analysis (ITA) tool was developed, and then for testing and validating this model, extensive experiments were carried out at Hydraulic Laboratory of Shahid Chamran University of Ahvaz to collect the necessary data. A selected set of data corresponding to two leak locations with different sizes was used to assess the ITA method. Results indicated that the leak location can be accurately pinpointed using a sample size equal to one period (T=4L/a) of the collected pressure in ITA. The error for estimation of the location for a significant leak was between 0.17% and 2.17% of the pipe length. Also, using two periods (2T) of the pressure signal, the uncertainties in leak quantity estimation were satisfactory, as less than 23% of the real leak quantity. Additionally, the comparison between the observed data and the numerical results in different conditions indicated that the hydraulic model estimated the transient pressure accurately by just incorporating the pipe wall viscoelasticity into the model.
Technology, Water supply for domestic and industrial purposes
Mohammad Delnavaz, Vahid Vatanpour, Javad Farahbakhsh
Water desalination systems is among the methods used to produce potable water to be used for domestic, agricultural and industrial applications. Reverse osmosis is a common methods employed for desalination facilities, mainly because of its low energy consumption, and high efficiency for permeate production. The main aim of this research is to use nanocomposite containing carbon nanotubes to improve membrane wall performance. in addition, the increase in the flux as a result of decreased clogging surface on the membrane was also studied. To accomplish the objective of the study, the synthesized polyamid reverse osmosis nanocomposite membrane were used for purification of brackish water with the characteristic of having the electroconductivity of 4000 µs/cm. The modified raw-multi walled carbon nanotubes membrane was embedded through polymerization method in order to increase porosities and hydrophilicity. Analysis of Contact angle, SEM, FTIR and AFM were done for recognizing the compounds which were created on the surface of membranes and membranes hydrophilicity. Three sets of samples were prepared for testing in the membrane cell synthesis analysis. Water flux and rejection rates were assessed every 30 minutes. Results of this study showed that the membranes have soft hydrophil surfaces and by increasing nanocomposite concentrations with specified measure, the water flux increased up to 30.8 L/m2h which was noticeable compared to the simple polyamide membranes. Our results also showed that fouling reduced considerably and the clogging condition was reduced by nanocomposite membranes, and the rejection rate was higher than 97 percent for all synthesized membranes with pyrrol.
Technology, Water supply for domestic and industrial purposes
It is observed that physical changes in the filter as bed media size variation, nozzle breakage, or water temperature variations lead to changes in the backwash regime throughout the year. The remedy proposed in this article is to use variable speed pumps in order to maintain a constant and steady optimum regime. In this study, experiments were performed using a full-scale single-layer rapid sand filter to find the optimum bed expansions of 7-8%. In addition, previous research has shown that air and backwash water flows need to be slowly and gradually increased to the optimum design values in order to avoid sand boil. In a typical treatment plant, this is normally controlled by globe valves, which results in the waste of energy and variation in pump and blower pressures. Application of variable speed pumps has the advantage that a constant pressure can be maintained throughout to yield an optimum backwash regime. Variable speed pumps provide various backwash regimes which enable design engineers and water plant operators to determine the optimum expansion in sand bed filters. This range of optimum bed expansion was found to lead to such improvements as shorter filter ripening, reduced effluent turbidity to levels below 0.3 NTU, conservation of backwash water by up to 15‒20%, and savings in backwash pump power consumption by up to 30-50%.
Technology, Water supply for domestic and industrial purposes
The supply of water with a desirable quality and at required quantities by water distribution networks (WDNs) requires exorbitant costs over their effective life. Optimized network design is, therefore, not only a basic and most decisive step toward reducing costs but will also serve a means for considering other quantitative and qualitative criteria in the design process. In this study, a gravitational network with two reservoirs was investigated to determine the effects of the quantitative parameter of resilience index and the qualitative parameter of free chlorine residual on network design costs. The quantitative parameter used gurantees network efficiency at critical demand times through creating extra capacity while the qualitative one is meant to ensure adequate concentrations are maintained throughout the network. For this purpose, a Genetic Algorithm (GA) was written in the Matlab code and incorporated into the EPANET Toolkit to perform thorough WDN hydraulic and water quality analyses. Results showed that the proposed method was capable of creating a logical and consistent relationship between quantitative and qualitative parameters, on the one hand, and design objectives, on the other, although the WDN costs are only slightly increased. It was concluded that the method could be exploited as a new basis for selecting the final WDN optimal design.
Technology, Water supply for domestic and industrial purposes
In hydraulic, velocity distribution as a key parameter for determining the flow profile, such as flow, shear stress distribution, sedimentation, erosion, loss of head, the coefficient of energy and momentum coefficient is needed, so the calculation of flow velocity is an important part of sewers design. The flow in a sewer, regardless of its geometry, is three-dimensional turbulent free surface flow. The introducing of the entropy based on probability in hydraulic by Chiu gives the possibility to develop a simple equation to evaluate the velocity and the discharge in the cross section. The method was applied to a study of velocity field of flow in narrow compound sewer. The primary flow distribution was investigated under various hydraulic conditions. The validation of the method and velocity distribution and discharge was carried out by comparing the estimated results with the measured findings at the field sites. Analysis of velocity distribution based on the probability concept has made it possible to determine the cross-sectional primary velocity distribution and discharge without having to deal with the geometrical shape of cross sections, which tend to be extremely complex in real sewers.
Technology, Water supply for domestic and industrial purposes
The photocatalytic UV/TiO2 process has particular importance due to having high rate and efficiency in the removal of organic and inorganic contaminants from industrial wastewater. One of the problem of utilization of a catalyst with physical properties similar to TiO2 (anatase) is the separation of the catalyst from the wastewater effluent. In this study, synthesis of titanium oxide on the surface of alumina (particle size 150 to 200 µm) with the wet impregnation method was accomplished in order to create a catalyst with suitable physical properties to easy separation capability from industrial effluents. Hence, titanium isoprpylate compound was used and after the reaction of alumina on the surface, in order to Synthesis of titanium oxide anatase form, calcinations being done in the temperature of 500 ◦C in an electric furnace. The amount of anatase phase formation was measured by X-ray diffraction technique. Finally the removal of free cyanide in the presence of TiO2 and Al2O3/TiO2 was investigated in optimal conditions with the Change of parameters such as irradiation time of UV, the amount of catalyst and initial concentration of cyanide. Experiments were carried out by using a batch photoreactor and a high pressure Hg lamp (250 watt). The results indicated that a layer of anatase TiO2 formed on the surface of Al2O3particles which its value depends on the increasing frequency synthesis. The study of the kinetic of
cyanide removal process in the presence of the synthetic catalyst Al2O3/ TiO2 showed that the curve of concentration versus time is logarithmic in this process which indicated the reaction is the first order The results also showed that the catalyst TiO2 has a greater Photocatalytic activity in removal of cyanid compared to Al2O3/ TiO2 due to its higher purity and tiny particle size. However, the physical properties of Al2O3 /TiO2 catalyst including easy separation and reuse from industrial effluent in removal process, could justify economical and practical of its application.
Technology, Water supply for domestic and industrial purposes
Navid Ghajarnia, Omid Bozorg Hadad, Salah Kochakzadeh
This paper investigates the application of a multiobjective algorithm in the problem of multiobjective design of water distribution networks. The problem is formulated using two different objective functions: minimizing cost and maximizing reliability. To measure the reliability, a new definition based on the original concept of fuzzy logic, named “Fuzzy Reliability Index” is introduced. Then, developing the Multi Objective Honey-Bee Mating Optimization algorithm based on it’s single objective version, the multi criteria design of two benchmark networks is performed using predefined objective functions. The results obtained show that the proposed reliability index is able to provide desired reliability in the network. Furthermore, satisfactory results obtained by the algorithm in defining the pay off characteristic between total cost and reliability are shown. Finally, it is possible to use the developed model to introduce different and numerous non-dominant solutions to decision makers.
Technology, Water supply for domestic and industrial purposes
Hossein Hosseinpour Niknam, Mehdi Azhdari Moghadam, Mahmoud Khosravi
In this research in order to forecast drought for the next coming year in Zahedan, using previous Standardized Precipitation Index (SPI) data and 19 other climate indices were used. For this purpose Adaptive Neuro-Fuzzy Inference System (ANFIS) was applied to build the predicting model and SPI drought index for drought quantity. At first calculating correlation approach for analysis between droughts and climate indices was used and the most suitable indices were selected. In the next stage drought prediction for period of 12 months was done. Different combinations among input variables in ANFIS models were entered. SPI drought index was the output of the model. The results showed that just using time series like the previous year drought SPI index in forecasting the 12 month drought was effective. However among all climate indices that were used, Nino4 showed the most suitable results.
Technology, Water supply for domestic and industrial purposes
Aniline is a first type amino aromatic compound and has various applications in different pharmaceutical, synthetic dye, plastic, and petrochemical industries. It is poisonous and its discharge into the environment causes serious hazards that warrant it removal by an efficient treatment process. In this study, the efficiency of rotating biological contactors in aniline removal was investigated using four 3-liter parallel systems (in two series). Two reactors in the first series had 27 disks. The second series had 14 discs with packings in each reactor with the same specific surfaces as compared to the first system.Aniline concentrations from 100 to 1200 mg/L and hydraulic loading rates from 1.57 to 6.28 L/m2.d were used throughout the study period in two treatments. The effect of disc rotation speed on system efficiency was also investigated. The results indicated that COD removal efficiency decreased with increasing hydraulic loading rate but increased with increasing disc speed from 5 to 15 rpm. The best removal efficiencies of 88 and 86 percent for RBCI and RBCII, respectively, were obtained for an aniline concentration of 400 mg/L, a hydraulic loading rate of 1.57 L/m2.d, and a disc speed of 15 rpm. Based on the results, although both systems yield almost equal efficiencies, the start-up period was shorter in RBCII with a clearer effluent due to the lower quantity of suspended microorganisms in the reactor than that in RBCI. Use of packing may decrease energy consumption for disc rotation due to the overall weight reduction of the system.
Technology, Water supply for domestic and industrial purposes
There are many methods for increasing efficiency of turbidity removal such as tube settler, rotating plate or gradient parallel plate. In this study was evaluated conventional sedimentation basin which equipped by lamella system. The pilot used in the study was made up of poleax glass hexagonal having effective height of 1.2m with hydraulic diameter of 50-80 mm. The slope of sedimentation basin was 600 at the basis of horizon. The lamella system was installed onto a segment which located 150 at the basis of center of sedimentation basin. The pilot was located in Isfahan Water Treatment Plant. In fact the segment isolates sedimentation basin into two compartments, first with lamella and another without it.The turbidity of influent and effluent in two compartments were evaluated by SPSS software and T-Student.The result showed that at same condition without lamella, the minimum, maximum and average turbidity removal efficiency in Isfahan Water Treatment Plant were about 0.9%, 54% and 18.9% respectively. But in compartment equipped by lamella system The removal were about 20%, 65% and 35.3%. It can be concluded that the turbidity removal efficiency will be increased if the sedimentation basin would equipped by lamella system.
Technology, Water supply for domestic and industrial purposes