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Biological treatment together with sorption and clarification techniques are often applied to treat municipal and industrial (petrochemical, food and pharmaceutical) wastewater. Often treated wastewater does not meet technological standards to be reused for industrial purposes such as: cooling, heating, boiler feed or steam generation. Production o...
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... particulate weight study was implemented using 1 liter laboratory glass cylinders ( Figure 11). To evaluate weights of particles, their sedimentation rates were determined. ...
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... treat wastewater To facilitate RO process design relationships and equations were developed to determine the required oil rejection for selected recovery values and feed water TDS (Figure 12). The graphs shown on Figure 11 are developed using the least square method. The developed equation to determine the required rejection is exponential relationship: Y = cXb, where Y -membrane rejection, % X -feed flow decrease ratio: X= 1/ (1-Qp/Qf) , where Qp is product flow rate, Qf -feed flow rate, and Qp/Qf is recovery. ...
Citations
... The product rate, rejection, and flux will all growth along with the effective pressure. The rejection rate is larger than the product rate because of the compacting and polarization that occur on the membrane surface (Junaidi et al., 2020;Pervov, et al., 2018). With increased operating pressure, there is a significant increase in TDS rejection (Junaidi et al., 2020). ...
The conversion of saltwater and brackish water into fresh water through desalination has gained significant importance as a solution to the worldwide scarcity of fresh water resources. The Reverse Osmosis (RO) method has been effectively utilized to generate fresh water from sources of brackish water. This research aims to examine the variables that affect the performance of the reverse osmosis process. The effectiveness of the membrane was assessed through experiments that explored the impact of varying operating conditions, such as feed pressure, temperature, and concentration, on the reverse osmosis pilot plant and salt solution system (consisting of NaCl and MgCl2). The selected membrane used a polymeric membrane constructed as FilmTec TW30-1812-50 spiral-wound module. The results showed that as the feed temperature and salt concentration increased, the salt rejection decreased. On the other hand, as the transmembrane pressure was raised, the membrane's salt rejection improved. The experiments revealed that the feed temperature and salt concentration have a significant impact on the membrane's performance. Among the various variables studied, operating pressure had the largest effect on the product rate. As operating pressure increased, the permeation flux and salt rejection also increased, with a salt rejection rate of 96% achieved at 5 bars. In addition to other factors, the concentration of the feed greatly influences the solute content in the final product.
... Thus, removing pollutants from wastewater has attracted intense research worldwide [5]. There are various treatment methods that have been developed such as chemical oxidation, coagulation, filtration, precipitation, ion exchange, biosorption, adsorption, reverse osmosis, and photocatalytic decay... [6][7][8][9][10][11][12][13]. Photocatalysis is a notable method of removing pollutants from wastewater with its low cost, high efficiency, and environmentally friendly properties. ...
The authors report the characteristics and optical properties of Bi3+-doped SnO2 quantum dots prepared bysol-gel and hydrothermal methods. The structure and morphology of the materials as a function of dopingconcentration were studied and analysed by X-ray diffraction (XRD) and scanning electron microscope(SEM). The structure of the material was assigned to the tetragonal crystal structures of the SnO2 rutile phase,reported in JCPDS Card No. 41-1445. With the increase of Bi3+ doping, the crystallinity of Bi-doped SnO2worsened. The average sizes of the SnO2 nanocrystals were within 3-8 nm. The effect of Bi3+ ion concentrationon the absorbance properties of the materials was investigated by UV-Vis absorption spectra. The absorbancedecreased with increasing the concentration of Bi3+ dopant in the SnO2 lattice. The bandgap width decreasedwith Bi3+ dopant concentration. All Bi3+-doped SnO2 samples presented an enlargement of the light absorptionrange due to a bandgap width decrease.
... Most of the time, they have disadvantages. For instance, due to membrane blockage in reverse osmosis, routine maintenance is needed [62,108]. It has been suggested to employ bioremediation to break down organic contaminants utilizing naturally existing microorganisms such as algae, bacteria, and fungi [49,162]. ...
Water is one of the most defining characteristics of our mother planet and also the human body, hence, it is essential to all aspects of life. On a sad note, the increasing anthropogenic activities towards the discharge of novel and known pollutants into these existing water bodies is a serious challenge. Emerging organic contaminants include newly synthesized compounds and also compounds just discovered as contaminants such as dyes and dyestuffs, pesticides, pharmaceutical products, phenols, industrial additives, microbeads, and microplastics. There is an inextricable link between these pollutants and wastewater. They are of great concern in modern science as they destroy the ecosystem at large, dangerous to human health and plants, due to their toxicities. In light of these, several remediation techniques have been embarked upon, out of which degradation by adsorption has been identified as the most promising because of their ease of operation and cost efficiency. This present study is intended to shed more light on the preparation, characterization, and activation of metal organic frameworks for the removal of these emerging organic contaminants from our water bodies through adsorption.
... Among numerous methods available, some of the most important processes involved in the water pollution mitigation purposes include chemical precipitation, ion exchange, membrane filtration, coagulation-flocculation, flotation electrochemical methods (explained in supplementary material) and adsorption at the solid-liquid interfaces [19].The conventional process like coagulation has the disadvantage of incomplete removal of metal ions, high cost, secondary sledge formation and lowering of pH of the medium [20][21][22][23]. Similarly, for reverse osmosis and the membrane filtration clogging of the membranes leads to frequent servicing and replacing of membrane are the main draw backs [24,25]. ...
The paper reports the global applicability of adsorption as one of the most sustainable processes that can be technologically transform into a factorial model in mitigating heavy metals from wastewaters. Adsorption has received greater attention among many techniques on the verge of declining interest, primarily due to ecological, economic and waste by-product management issues. This perspective adsorption method is the key focus of the review by exploring the latest research works progressing globally regarding adsorbent materials with tunable adsorption capacity and selectivity for metal ions and promising optimal appreciation of both ecology and economy. The different adsorption parameters involved in the adsorption and its influence on the entire process are validated through the literature survey. The different ways in which the adsorption mechanisms are predicted concerning pH and various spectroscopic studies are also discussed. This review paper covers a broad spectrum of adsorption data of operational parameters that can influence the adsorption process's rate, prediction of adsorption mechanism employing the spectral analysis and the modern adsorbents with more significant activity for the metal ions. The comparison tables are prepared systematically by introducing current adsorbents, adsorption capacity, kinetic, isotherm and thermodynamic aspects to reveal the complete adsorption profile of the introduced adsorbents. Adsorbent materials are classified based on the trending interest of prevailing researchers. Accordingly, the paper gives a comprehensive and informative study on adsorption till today.
... Recently, several technological alternatives that are either biological or physicochemical or hybrid of both, have been adapted to target specific pollutants and treat wastewater to a reusable standard (Galkina and Vasyutina, 2018;Stefanakis, 2016;Ngo et al., 2002). They include Advanced oxidation processes (Comninellis et al., 2008;Mishra et al., 2017), Membrane bioreactor (Schlosser, 2014;Fazal et al. 2015;Iorhemen et al. 2016;Stefanakis, 2016), Reverse Osmosis-based wastewater treatment (Trishitman et al. 2020;Anis et al., 2019;Pervov et al., 2018), Activated Carbon Filtration (Saleh et al. 2015;Azis et al., 2021;Kamal et al. 2019;Benstoem, and Pinnekamp, 2017) and Constructed Wetlands (Omandi and Navalia, Figure 9. Conventional Wastewater Treatment Plant integrated with operational AD system for biogas production and electricity generation. G.N. Ijoma et al. ...
Several anthropogenic activities reduce the supply of freshwater to living organisms in all ecological systems, particularly the human population. Organic matter in derived wastewater can be converted into potential energy, such as biogas (methane), through microbial transformation during anaerobic digestion (AD). To address the current lack of data and values for wastewater generation in Sub-Saharan Africa, this review analyzes and estimates (at 50% and 90% conversion rates) the potential amount of wastewater-related sludge that can be generated from domestic freshwater withdrawals using the most recent update in 2017 from the World Bank repository and database on freshwater status in Sub-Saharan Africa. The Democratic Republic of the Congo (DRC) could potentially produce the highest estimate of biogas in Sub-Saharan Africa from domestic wastewater sludge of approximately 90 billion m³, which could be converted to 178 million MWh of electricity annually, based on this extrapolation at 50% conversion rates. Using same conversion rates estimates, at least nine other countries, including Guinea, Liberia, Nigeria, Sierra Leone, Angola, Cameroon, Central African Republic, Gabon, and Congo Republic, could potentially produce biogas in the range of 1–20 billion m³. These estimates show how much energy could be extracted from wastewater treatment plants in Sub-Saharan Africa. AD process to produce biogas and energy harvesting are essential supplementary operations for Sub-Saharan African wastewater treatment plants. This approach could potentially solve the problem of data scarcity because these values for Freshwater withdrawals are readily available in the database could be used for estimation and projections towards infrastructure development and energy production planning. The review also highlights the possibilities for energy generation from wastewater treatment facilities towards wastewater management, clean energy, water, and sanitation sustainability, demonstrating the interconnections and actualization of the various related UN Sustainable Development Goals.
... In the case of the anaerobic biological treatment of sulfate-rich wastewater, the main concern is sulfide generation, which is toxic to bacteria and corrodes the reactor [15]. Commercially accessible reverse osmosis facilities have high fouling propensities, require costly pretreatment, and produce environmentally damaging concentrates [16]. The limitations of ion exchange processes in wastewater treatment include iron and calcium sulfate fouling, organic contamination from the resin, organic matter adsorption, and contamination of bacteria with chlorine [17]. ...
... All patterns expose basal spacing reflections of (003), (006), (009, 012), and (110) close to 2θ ¼ 10 0 , 22 0 , 35 0 , and 61 0 respectively. Additionally, the sharp, symmetric peaks at the lower angles and the broad, weak peaks at higher angles can be attributed to the high crystallinity of a naturally occurring hydroxycarbonate of Mg and Al, with the formula Mg 6 Al 2 (OH) 16 Table 4). The specific surface area of the synthesized LDH 4Mg2Al⋅NO 3 and LDH 8Mg2Al⋅NO 3 were 26.38 and 5.67 m 2 /g, respectively. ...
Sulfate-contaminated water is a major environmental problem that alters the taste of water, disturbs the digestive systems of animals and humans, and erodes both soil and metals. In this study, the layered double hydroxide (LDH) 4Mg2Al.NO3 and LDH 8Mg2Al.NO3 were prepared using a co-precipitation technique, and applied in the adsorption of SO4²⁻ from an aqueous solution. The reaction is well described by the Langmuir adsorption model. LDH 4Mg2Al.NO3 and LDH 8Mg2Al.NO3 afforded maximum SO4²⁻ adsorption values of 135.14 and 92.59 mg/g, respectively. The reaction is best explained by a pseudo-second-order mechanism, which suggests that chemisorption is the rate-determining step. The activation energies of LDH 4Mg2Al.NO3 and LDH 8Mg2Al.NO3 indicate that the adsorption of SO4²⁻ on synthetic LDHs predominantly follows an anion-exchange mechanism, wherein SO4²⁻ ions in the aqueous medium replaces intercalated NO3⁻ ions in the synthetic LDHs. The thermodynamic parameters (ΔH̊, ΔS̊, and ΔG̊) were also calculated. The reaction was endothermic, and the synthetic LDHs afforded feasible and spontaneous adsorption of SO4²⁻.
... The application of RO in the water treatment and desalination process is very widely used today [6]. RO process can be used to overcome the problem of water in areas where the source of water is sea water or brackish water [7][8][9], processing brackish water into clean water using a reverse osmosis membrane [10], taking back water from wastewater [11] Reverse Osmosis for reduce the salinity of raw water [12]. RO processes are preferred over thermal processes [8]. ...
... Rejection rate is greater when compared to the product rate, this is due to the compacting and polarization that occurs on the membrane surface [10][11][12]. Meanwhile Rejection to TDS increases with increasing operating pressure [10] starting from 96.6% at a pressure of 20 Psig and rising to 97.5% at a pressure of 50 Psig as shown in Figure 2. Table 3, it can be seen that the rate of pure water production rises with increasing pressure as well as in Table 4 the rejection rate increases with increasing pressure, TDS and conductivity also increases while resistivity decreases with increasing pressure due to increasing ions in the rejection flow [10][11]. ...
This research was conducted to determine the performance of Reverse Osmosis (RO) membranes in producing pure water, pure water known as mineral-free water or water with zero dissolved solids (TDS = 0 ppm).PDAM (Regional Drinking Water Company) Tirta Musi in Palembang, South Sumatra and water from the Micro Filtration (MF) and Ultrafiltration (UF) processes are fed to the RO process using two feeding methods, namely a single pass and a circulation feed. In a single pass feed, the operating pressure is set at 20 - 50 Psig, where an increase in the product rate and the rejection rate so that the flux increases. Rejection of TDS obtained increased from 96.6% - 97.5%. Furthermore, the circulating feed system with a constant pressure of 50 Psig decreases TDS and Conductivity. Rejection of TDS 96.1% for PDAM water feed and Rejection of TDS for feed water from MF&UF 97.3% in subsequent feedings there was a decrease in TDS and conductivity but not significantly. The purified water produced has a TDS content of 0.16 - 0.48 ppm, a conductivity of 0.17 - 0.49 μs/cm, a pH of 6.99 - 7.2 and a resistivity of 177 - 185 kΩ, the characteristics of this pure water are according to the standard pure water in ASTM D1193 - 99e1 and NCCLS.
Metal-organic frameworks (MOFs) are amongst the most attractive porous polymeric networks with appealing properties. However, their inherent fragility, powder nature, low processibility, and handling present some exceptional challenges for high-tech commercial applications. Currently, economic and environmental concerns drive the development of some bioinspired polymeric matrices containing MOFs. As an artifact, the availability of previously unattainable properties is negotiated by conjugating cellulosic materials with crystalline MOFs. Thus, multi-dimensional organic-inorganic hybrid composites are formed with high electrical, optical, mechanical, and thermal features. These MOF/cellulose hybrids, known as CelloMOFs (cellulose MOFs), have remarkable mechanical properties with tunable porosities, specific surface area, and accessible active sites, making them ideal for real-world troubleshooting applications such as wastewater treatment, chemical sensing, energy storage, and so on. In this review, current state-of-the-art strategic synthesis routes for fabrication on MOFs/Cellulose composites with a specific focus on CelloMOFs as a potential tool for mitigation of the targeted emerging water contaminants have been done under the same umbrella, which has previously been less explored. Streamlining discussions on general properties such as raw material selection, structural analysis of cellulose, availability of surface functional groups, cellulose-metal node interactions, cellulose charging, and so on have been emphasized, as has integration with robust MOFs. A better understanding of these fundamental properties is critical because they will have a significant impact on the performance of MOF/cellulose composites in a variety of applications. Furthermore, at the end of this review, the challenges and perspectives of using CelloMOFs have been discussed in a concise manner in order to improve their practical utility rather than just concept mapping.
Water-borne emerging pollutants are among the greatest concern of our modern society. Many of these pollutants are categorized as endocrine disruptors due to their environmental toxicities. They are harmful to humans, aquatic animals, and plants, to the larger extent, destroying the ecosystem. Thus, effective environmental remediations of these pollutants became necessary. Among the various remediation techniques, adsorption and photocatalytic degradation have been single out as the most promising. This review is devoted to the compilations and analysis of the role of metal-organic frameworks (MOFs) and their composites as potential materials for such applications. Emerging organic pollutants, like dyes, herbicides, pesticides, pharmaceutical products, phenols, polycyclic aromatic hydrocarbons, and perfluorinated alkyl substances, have been extensively studied. Important parameters that affect these processes, such as surface area, bandgap, percentage removal, equilibrium time, adsorption capacity, and recyclability, are documented. Finally, we paint the current scenario and challenges that need to be addressed for MOFs and their composites to be exploited for commercial applications.
