Common Effluent Treatment Plant Research Articles

Waste management and salt recovery from solid residue of tannery common effluent treatment plant

ABSTRACT The considerable amount of solid residue generated by the common effluent treatment plant (CETP) of tanneries needs adequate treatment and reclamation before ending up in the environment as solid waste. A sustainable process aiming at tannery CETP waste minimisation and its reuse for sodium chloride salt recovery is presented. The integrated approach consists of dissolution, decolorisation, filtration, evaporation, and crystallization as unit operations. Lab-scale parametric studies have been undertaken to investigate the effects of various parameters at different process stages on product (sodium chloride) yield and quality. The developed process resulted in the recovery of 93% NaCl, having a purity of ∼98.5%. The optimised operating conditions were tested on a bench-scale system (15 kg batch scale of solid residue) deploying solar energy for evaporation-crystallization, and process feasibility was established. An economic analysis was performed, and the techno-economic feasibility was demonstrated to produce 15,733 tons per annum (TPA) of NaCl from 20,000 TPA of solid residue. The techno-economic analysis favours the treatment of tannery CETP waste with the method specified. The proposed scheme can tackle waste management and reuse the recovered product in the tanning process.

Assessing the Effects of Tannery Pollutants in Tamilnadu: Special Reference to Chennai City

A study was carried out to assess the chromium content of groundwater in the vicinity of tanneries in a district of Chennai, southern India. The common effluent treatment plant (CETP) treats the sewage from these tanneries before releasing it into open drains that connect to the neighbouring Adyar River. Tanneries are one of the industries that significantly contribute to pollution in the Chennai district. Chennai, the study region famous for having an airport in the district, is a rapidly urbanising area. There are many tanneries in the vicinity, and their effluents frequently impact the nearby land and water since they are not treated. The chemicals that lead to the area’s degradation have been identified by chemical analysis of the collected water samples.

Life cycle assessment of a common effluent treatment plant: Case study of Mahad, India

Common effluent treatment plants (CETPs) offer extensive benefits for wastewater treatment in developing countries in terms of cost-effectiveness, industrial synergy, and resource conservation. Evaluating the performance of CETPs is essential to ensure sustainable practices in wastewater management. The present study aims to assess the environmental impacts of a CETP situated in Maharashtra, India, using the life cycle assessment method (LCA) as per ISO 14040:14044. The plant comprises a primary, secondary, and tertiary treatment unit along with a sludge handling unit. The inventory analysis was performed using the averaged data collected from the plant for a year. The secondary inputs were taken from the GaBi 10.6 database suited to the Indian context. The study employed a gate-to-grave LCA approach and the functional unit was assumed to be 1000 m3 of treated water. The impact analysis was conducted with the help of the CML 2001: Aug 2016 method. It was found that the primary and secondary treatment units offered the highest environmental burden. Both the treatment units contribute about 70–80 % to all the categories except for ADP-elemental, where the contribution is about 98 %. Electricity was identified as a predominant factor contributing to the impacts under most midpoint categories except for ADP-elemental. A scenario analysis was undertaken to estimate the possibility of adapting to renewable energy to reduce environmental footprints. The impacts generated under such a scenario were lower than the original observations, except for the ADP–elemental category. The study emphasizes how LCA helps optimize areas under investigation and fosters sustainable treatment practices in wastewater treatment.

Integrated Fenton-like and ozonation based advanced oxidation processes for treatment of real-time textile effluent containing azo reactive dyes

The treatment of real-time textile effluent, collected from the Common Effluent Treatment Plant (CETP) of Kerala Industrial Infrastructure Development Corporation (KINFRA) at Kannur (District), Kerala (State), India, have been studied by utilizing the Fenton-like and ozone (O3) based advanced oxidation processes (AOPs). The Fenton-like AOP has been conducted as the pre-treatment of textile effluent involving the activation of persulfate (PS) and hydrogen peroxide (H2O2) as a single and the mixed oxidants by using the Flyash (FA)-Pd composite particles as the activator. The maximum chemical oxygen demand (COD) removal of 84% has been observed for a stand-alone O3 based treatment at an O3 flow rate of 5–6 g h−1. By conducting the pre-treatment of textile effluent with the PS, H2O2, and mixed oxidants (PS and H2O2) based Fenton-like AOPs, the COD removal after an O3 based post-treatment has been observed to be 83, 87, and 93% respectively at an O3 flow rate of 2, 3, and 5 g h−1. Hence, the Fenton-like pre-treatment involving the activation of mixed oxidants has been determined to be the best method for the highest COD removal of real-time textile effluent. The optimum values of initial oxidant-ratio (initial [H2O2]:initial [PS]), initial oxidant-dosage, and ozonation time, for the mixed oxidants based Fenton-like pre-treatment, have been determined to be 3 wt% mM−1, 6:2 wt% mM−1, and 60 min respectively. Under the most optimum conditions, the COD removal has been attributed to the combination of O2•- (for the pre-treatment) and •OOH (for the post-treatment) which possess relatively lower oxidation potential values.

Bioremediation of Cr(VI) using indigenous bacterial strains isolated from a common industrial effluent treatment plant in Vishakhapatnam

Abstract The present study focuses on removing hexavalent chromium (Cr(VI)) using indigenous metal-resistant bacterial strains isolated from a common industrial effluent treatment plant, a contaminated site in Vishakhapatnam. Three high metal-resistant isolates were screened by growing them in nutrient agar media containing different Cr(VI) concentrations for 24 h at 35 ± 2 °C. The three strains’ minimum inhibitory concentrations of Cr(VI) were examined at neutral pH and 35 ± 2 °C temperature. Morphological, biochemical, and molecular characterizations were carried out, and the strains were identified as Bacillus subtilis NITSP1, Rhizobium pusense NITSP2, and Pseudomonas aeruginosa NITSP3. Elemental composition and functional group analysis of the native and metal-loaded cells were done using energy-dispersive spectroscopy and Fourier-transform infrared spectroscopy, respectively. The operating conditions were optimized using a one-factor-at-a-time analysis. When compared with three bacterial isolates, maximum Cr(VI) removal (80.194 ± 4.0%) was observed with Bacillus subtilis NITSP1 with an initial Cr(VI) concentration of 60 mg/L, pH 7.0, an inoculum size of 2% (v/v), and an incubation period of 24 h. The logistic model was used to predict the variation of biomass growth with time. The present study can be extended to remove heavy metals from industrial wastewater in an environmental-friendly manner.

Chitosan and its derivatives in wastewater treatment application

Chitosan, a versatile and environmentally friendly biopolymer derived from chitin, has emerged as a promising material for wastewater treatment applications. Its unique properties, such as biodegradability, biocompatibility, and adsorption capacity, make it an attractive option for addressing the growing challenges of water pollution. This paper provides a comprehensive review of the use of chitosan and its derivatives in various aspects of wastewater treatment. It explores the synthesis and modification of chitosan to enhance its effectiveness, discusses its mechanisms of action, and highlights its applications in coagulation, flocculation, adsorption, and membrane processes. The paper also delves into the challenges and future prospects of chitosan-based wastewater treatment, emphasizing the potential role of this natural polymer in sustainable water management. The wastewater from common effluent treatment plant (CETP) was used for treatment and significant results are obtained.

Characterization of inorganic and organic pollutants load in tannery wastewater: Biochemical and haematological induced changes in Swiss mice

The aim of the present study is to characterize the inorganic and organic contaminant loads in hazardous TWW and their effects on a number of biochemical and hematological changes in Swiss mice at four concentrations: C (control purified water), L(low 2.5 % TWW), M(medium 5.0 % TWW), and H(high 10 % TWW). Significant differences were observed in the chemical characteristics of TWW between the inlet and outlet of the common effluent treatment plant (CETP) in Unnao district, Uttar Pradesh, India. Physicochemical parameters such as EC, TDS, BOD, chloride, sulfate, hexavalent chromium and total nitrogen were many times higher than the Central Pollution Control Board (CPCB) limits, while other parameters such as phosphate (as P), F−, Fe, Pb, Cu, Zn, Cd and Co were within the limits. The TWW intake significantly increased Swiss mice's body weight with increasing the dose of TWW. Biochemical parameters, i.e., AST, ALT, AP, glucose, cholesterol, and triglyceride increased significantly with increasing TWW dose, whereas serum creatinine and total albumin decreased, while no specific trend was observed for urea. haematological changes indicated that hemoglobin, RBC, blood platelets, and WBC like LYM, MON, and NEU decreased significantly with an increase in TWW dose, HCT, MCV, MCH and MCHC significantly decreased.

Techno-economic assessment of integrated photochemical AOPs for sustainable treatment of textile and dyeing wastewater

Textile and dyeing industries generate large quantities of wastewater rich in colourants, dyes, chemicals, surfactants, etc. Notably, textile effluents are highly coloured, toxic, odorous, and with high chemical oxygen demand (COD) and low biochemical oxygen demand (BOD). These colour-causing complex organic compounds in wastewater streams are not completely degraded or removed using conventional physicochemical and biological treatment processes. Although as per regulatory norms, COD, colour, and BOD need to be eliminated if the treated water is to be reused. A batch-scale study of photochemical Advanced Oxidation Processes (AOP) to treat textile wastewater from a common effluent treatment plant is aimed to improve biodegradability and downstream performance. The assessment compared the techno-economic feasibility of integrating four photochemical AOPs with existing biological treatment plant in terms of their efficiency, energy requirement, and overall cost of treatment. Photochemical AOPs considered in this study were UV photolysis, UV/H2O2, UV photo Fenton, and UV/TiO2 photocatalysis. Although every treatment improved the quality of treated water, UV/TiO2 photocatalysis was the most promising for removing COD and BOD and required the least electrical energy per order (10.79 kWh/m3/order-COD removal and 5.16 kWh/m3/order-colour removal) whereas UV/TiO2 was the most economic (0.77 US dollar or INR 59.75/m3).

Acoustic cavitation for the process intensification of biological oxidation of CETP effluent containing mainly pharmaceutical compounds: Understanding into effect of parameters and toxicity analysis

The current work investigates the efficacy of acoustic cavitation (AC) based pretreatment as a process intensification method for improving the conventional biological oxidation (BO) treatment of the effluent from common effluent treatment plant (CETP) mainly containing pharmaceutical compounds. The effluent acclimatized with cow dung-based sludge was utilized for the aerobic oxidation with an optimum condition of 1:3 ratio of sludge to effluent and 6 h as duration. COD reduction of 19.58% was achieved with the conventional biological oxidation, which was demonstrated to be improved by incorporating acoustic cavitation-based pretreatment approaches under optimized conditions of 125 W and 70% duty cycle for only AC as well as oxidant loadings as 1000 mg/L for H2O2, 250 mg/L Fe(II) with 1000 mg/L H2O2 for Fenton, 1000 mg/L for KPS and 0.5 L/min for the O3 during the combination approaches. The improved COD reduction after the use of pretreatment approaches followed by the BO of 6 h duration was 29.26%, 72.42%, 85.47%, 45.68% and 69.26% for the AC, AC + H2O2, AC + Fenton, AC + KPS and AC + O3 based approaches respectively. The toxicity assay of the effluent before and after every pretreatment approach using bacterial strains ofStaphylococcus aureusandPseudomonas aeruginosaensured the biodegradability of the treated effluent as no toxic intermediates could be seen. Overall, the present work elucidated the effectiveness of acoustic cavitation-based pretreatment approaches for the improvement of conventional BO of CETP effluent.

Impact of lockdowns and possible quantification of pollution sources on the water quality of the Yamuna River

ABSTRACT The COVID-19 lockdown halted industrial and transportation networks, resulting in a change in the level of pollution. In this study, the analysis of pre- and post-lockdown water quality of the Yamuna River is done, and primary causes are identified, by considering five in situ parameters and four Landsat-8-derived parameters. During the 2020 lockdown, pollution-indicating in situ parameters decreased, with chemical oxygen demand decreasing the most, possibly due to reduced industrial impact. All satellite-derived indices improved during lockdown and post-lockdown periods of 2020. Even in segments with uniform flow, floating algal index and normalized difference vegetation index exhibited lower levels. In contrast, the examination of the 2021 lockdown revealed no noteworthy insights. Mapping the observations with the drainage network and location of common effluent treatment plants revealed that industrial effluents were the dominant cause of water quality fluctuations. This demonstrates the impact of industrial effluents on the degrading water quality of Yamuna.

Feasibility study of common effluent treatment plant for management of industrial wastewater: Case study of Bangladeshi textile industries

AbstractTextile industries play a vital role in the economy of Bangladesh contributing significantly to its gross domestic product. However, they are associated with high environmental pollution, especially water pollution. Since small‐scale textile industries cannot afford the treatment cost of discharged wastewater, they tend to contaminate water sources—both groundwater and surface water. To intervene in response to this situation, the existing treatment system was assessed in the present study. The effluents from industries under this research were analyzed for color, pH, TSS, TDS, chlorides, sulfates, COD, BOD, and total hardness. A Common Effluent Treatment Plant (CETP) with zero liquid discharge was suggested as a solution. It was observed that the water recovery in the proposed scheme by reverse osmosis and salt recovery using nanofiltration were 90%–95% and 80%–90%, respectively. Cost analysis also indicated that the cost of treating water can also be decreased by 18.7% which can show that water recovery is even more affordable for small‐scale industries. Finally, a linear programming model was developed to assist the industries with decision‐making in the selection of treatment schemes. This research revealed that a CETP using zero liquid discharge technology is a potential solution to the environmental crisis due to industrial wastewater discharge. This could ensure reduced water pollution, increased drinking water availability, improved public health, and thus could be a potential driver for environmental sustainability.

Chemical Investigation and Separation of Chromium from Chrome Cake of BSCIC Tannery Industrial Estate at Hemayetpur, Dhaka, Bangladesh

Leather tanning mainly depends on chrome tanning. A huge amount of basic chromium sulfate (BCS) is used in leather tanning. About 60–70% of BCS has been taken by leather and the rest of the amount is discharged as effluent and solid waste. In the Common Effluent Treatment Plant (CETP) of BSCIC Tannery Industrial Estate (Hemayetpur, Savar, Dhaka), the effluent which contained a high concentration of chromium is precipitated as solid chromium hydroxide with other elements which is called a chrome cake. Chrome cake is not exposed directly in the open space due to its toxic effect on human health as well as the environment. Human occupational experience distinctly indicates that, when inhaled, chromium compounds are respiratory tract irritants, resulting in airway irritation, airway obstruction, and lung, nasal, or sinus cancer. It is strongly suggested to extract Cr from the chrome cake before dumping it; otherwise, it will be a potential hazard to the environment. Herein, the chrome cake is characterized by inductively coupled plasma-optical emission spectroscopy (ICP-OES), X-ray fluorescence (XRF), UV-visible spectrophotometer, etc., and develops a method to separate chromium from chrome cake. ICP-OES and XRF analyses show that the total chromium contained in chrome cake is ∼17.45% and 20.7%, respectively. UV-visible spectrophotometer indicates that ∼0.04% of chromium is hexavalent. Afterward, chromium has been separated by using H2SO4 where the optimized concentration was found to be 7%. The separation efficiency of chromium from the chrome cake for optimized condition is obtained at ∼95%.

Experimental analysis on consumption of manufacturing waste in road construction and its environmental effects

All over the world, there has been a crisis of exploiting the natural resources for the development of surrounding environment in aid of construction industry. Also, it has been noted that, due to the technological boom, the waste accumulation has also been in a very huge proportion which is capable of causing serious environmental effects. Hence, an attempt is made to utilize the dumped waste has a replacement in road industry, which has made a greater impact0 with high prospects. The waste material that we have considered is copper slag from the unit situated at Tuticorin, Tamil Nādu, India, which generates 2600 tons of copper slag per day. In this industry, the copper slag waste after the treatment has been dumped in and around the land premises available at the industry itself due to insufficient utilization and also 10 to 20 tons of dry sludge is produced per day from the existing common effluent treatment plant. Hence in this research work, we recommend to use these waste materials over the construction of road through the evaluation of their required properties such as Physical and Chemical. The waste sample materials are tested for the determination of geotechnical characteristics by mixing them with the local clayey soils in the range of 25% to 75%. The probability of using these mixes in the sub grade of road pavement was studied in a detailed manner by conducting laboratory tests. The possibility of replacing the fine aggregate with copper slag in bituminous slag has been investigated. It was concluded that copper slag cannot be individually used as a sub base material. By means of conducting the necessary laboratory test, due to the dumping of slag around the premises causing environmental effects are evaluated and from which it has been identified that heavy metal concentration were in lower ratio than the pollution limits. The detailed technical specification over the design of utilizing the expected waste at the road pavement are discussed along with their data generated through the tests.

Persistence of Heavy Metals in River Sirsa Around Industrial Hub Baddi, India.

The Indian riverine system has become dumping site for toxic industrial pollutants. For assessing the flow of pollutants at various trophic levels, it is primarily important to do elemental profiling first so as to detect their load in Sirsa tributary of river Sutlej flowing through foothills of Shivalik in Himachal Pradesh, around the industrial hub Baddi, Solan. The study area includes three observation sites (S1, S2, and S3) on river Sirsa and drainage system of Baddi industrial units; the Effluent Nallah as demarcated in figure1. Heavy metal concentrations in water samples were detected using inductively coupled plasma mass spectroscopy of elements (Ti, V, Cr, Co, Ni, As, Li, Cd, Cs, Pt, Pb, Hg) as these were found to be very common in effluents of chemical, cement, textile dyeing, electronics and pharmaceutical industries. Statistical analysis showed that the concentrations (ppb) of elements found to be within permissible limits of WHO at sites under study for seven metals (Hg, Li, Ti, V, Co, Cs, Pt) but it was higher for five toxic heavy metals (Cr, Ni, Pb, As, Cd) at S2 only, streamlined in order Cr >Ni > Pb> As >Cd >Hg >Li >Ti >V >Co > Cs > Pt. It may be due to improper installation of common effluent treatment plant (CETP) on the bank of river Sirsa or due to leakage by tanker carrying waste water from various industrial set ups as these units were not directly linked to CETP. These sites were committed to act as ultimate gutter to receive all types of industrial pollutants as part of mismanagement. The load of Arsenic and Lead is increasing in lotic region and its impact on aquatic ecosystem at trophic level can be explored to combat toxicant pollution.

Assessment of Wastewater Quality Discharged from Common Effluent Treatment Plant (CETP) and its Impact on Irrigated Soil around Jajmau, Kanpur, India

Assessment of Wastewater Quality Discharged from Common Effluent Treatment Plant (CETP) and its Impact on Irrigated Soil around Jajmau, Kanpur, India

Failure mode and effects analysis of common effluent treatment plants of humid sub-tropical regions using fuzzy based MCDM methods

Common effluent treatment plants (CETPs) are used to collectively treat the effluents generated from different types of manufacturing industries of an industrial cluster before discharge so as to prevent the environment from the harmful effects of the effluents. There are several failure modes (FMs) that may lead to the failure of the CETP which may result in discontinuation of its operation. Thus, it is imperative to identify and estimate the criticality of the various FMs using failure mode and effects analysis (FMEA) in order to minimize the risk of failure of the CETP. This study identifies 24 potential FMs of the CETP, installed in humid subtropical regions, with the help of consensus among 5 experts who are the managers of CETPs installed at five different industrial regions of Delhi, the capital town of India. Subsequently, it applies a combined fuzzy based multi criteria decision making (MCDM) methods i.e. fuzzy analytic hierarchy process (FAHP) and fuzzy technique for order of preference by similarity to ideal solution (FTOPSIS) to derive rank of FMs. FAHP is applied to calculate the weights of three risk factors (RFs) i.e. occurrence (O) which refers to the chance of a failure cause occurring; severity (S) which measures the extent of effect of a failure cause on the system and the detection (D) which represents the chance of detecting the failure cause before the failure actually occurs. Then FTOPSIS is employed to determine rank of the FMs which signifies their criticality. The data required to implement FAHP and FTOPSIS are gathered from the experts in linguistic terms which are subsequently converted into equivalent triangular fuzzy numbers. Finally, sensitivity analysis is carried to ensure robustness of the ranking results produced by the combined FAHP and FTOPSIS method.

Microcosmic plant and fungi synergism-based filter to remediate the pollutants from industrial wastewater

Plants release compounds that signal microbes to engage in interactions. This interaction results in increased germination efficiency and root elongation, resulting in improved pollutant breakdown in both the rhizosphere and the phyllosphere. Most plants are symbiotic with fungi and these fungi play important roles in the structure, function, and health of plant communities. This study focuses on the potential of Syngonium podophyllum and Trichoderma harzianum fungi synergism to uptake the pollutants from the pretreated industrial wastewater collected from CETP common inlet point characterized by high COD (401 mg/l), BOD (159 mg/l), Nitrate (10.6 mg/l), and Lead (0.3 mg/l). Three setups S1 (Syngonium with Industrial wastewater water), S2 (Immobilized Trichoderma with Industrial wastewater), and S3 (Syngonium with Trichoderma & Industrial wastewater) were installed to treat pretreated industrial wastewater before entering CETP (Common effluent treatment plant). Compared to other treatments, the S3 setup was found more efficient to reduce the pollutants COD, BOD, NO3-N, and Pb by 82 %, 75.4 %, 70.7 %, and 80 % respectively in 6 days while S1 could reduce only 59.6 % COD, 63.1 % BOD, 42.4 % Nitrate and 80 % Lead and S2 setup reduced the COD, BOD, Nitrate, and Lead by 55.1 %, 40.8 % 33.9 % and 63.3 % respectively. The BCF (Bio Concentration Factor) and TF (Translocation Factor) of Syngonium were also improved in setup S3 (0.66 and 0.04 respectively) as compared to treatment setups S1 and S2. Based on the findings, it is feasible to conclude that using plant-immobilized fungal cell synergism for increased remediation of pollutants from wastewater is an environmentally benign and cost-effective strategy.

Treated tannery effluent and its impact on the receiving stream water: physicochemical characterization and cytogenotoxic evaluation using the Allium cepa test.

Tanneries are considered some of the most polluting industries due to the heavy use of toxic compounds, most of which are released into water bodies, thus exerting adverse effects on aquatic biota. However, the effects on organisms of treated effluents when released into the natural environment are rarely evaluated. This study aims to assess the physicochemical parameters of a tannery effluent after treatment (TE) at a Common Effluent Treatment Plant as well as the water of the receiving stream and to evaluate cytogenotoxic effects in Allium cepa. Three sampling sites (A: TE discharge point; B: 100m downstream from site A along the receiving stream; C: 100m upstream from site A along the stream) were selected. Onion bulbs were exposed to TE (100%, 80%, 60% v/v), water samples from sites B and C, and tap water for 72h. Chromosomal aberration and mitotic index were analyzed on the root cells of A. cepa. The TE was above the standard limits for ammoniacal nitrogen, COD, and total nitrogen. No cytogenotoxicity was observed in A. cepa exposed to samples from sites A and C. However, the stream water sampled downstream from the TE discharge site significantly reduced the mitotic index, indicating a cytotoxic effect. Therefore, this demonstrates the effects of interactions between the receiving water and the complex chemical mixtures in the TE. The findings thus showed that the toxicity assessment of treated effluents along with the receiving water body would provide valuable and more realistic information about the joint toxicity of chemical pollutants in aquatic environments.

Occurrence of Phthalates in common effluent treatment plants and removal by using Nano Titania-Graphene based photo-catalyst for tertiary treated effluent

The occurrence and effectiveness of common effluent treatment plants (CETPs) for the removal of phthalates, as well as the fate of DEHP, are demonstrated in this study using a nano TiO2-Graphene-based photo-catalyst and photolytic system. Full-scale CETPs were selected at SIDCUL, Haridwar, and Unnao, Uttar Pradesh, along with installing a lab-scale photocatalytic reactor. Solid phase extraction (SPE) and gas chromatography-mass spectrometry (GCMS) was used to extract and quantify four phthalates, namely DEP, DBP, BBP, and DEHP, and byproducts.The average concentration of DEP, DBP, BBP, and DEHP in the mixed industrial effluent of CETP Haridwar exceeded by around ten folds than the literature value. Still, it was removed significantly by 77.9%, 32.8%, 97.5%, and 41.8%, respectively.The average influent concentration was eventually lower than the treated effluent at CETP Unnao, and phthalates were not removed during the process. During process optimization, the distinct ability of each method to remove DEHP during photolysis and photo-catalysis was discovered. The UV-TiO2-GO had removal effectiveness of 98% in 30 min at pH-6. However, at a dose of 500 mg, UV and UV-TiO2-GO had removal efficacy of 73% and 86%, respectively, for 180 min. After de-esterification, the UV system only cleaved the aliphatic chain, leaving the aromatic ring intact and producing a variety of byproducts. The superoxide ions (O2°−) and hydroxyl radicals produced in the photocatalytic process attacked not only the aliphatic chain but also the benzene ring.

A novel synergistic effect of TiO2 and ZnO incorporation in PES-based thin-film nanocomposite nanofiltration membrane for treatment of textile wastewater.

A novel synergistic effect of TiO2 and ZnO incorporation in the PES-based thin-film nanocomposite nanofiltration membranes was developed for the treatment of common effluent treatment plant (CETP) textile wastewater. PES@TiO2 membranes were developed by phase inversion via the immersion precipitation method followed by the addition of zinc oxide nanoparticles prepared by the rapid microwave-assisted hydrothermal process via interfacial polymerization. p-Phenylenediamine was used as a monomer for the IP process that was coated on the PES@TiO2 support layer. Various techniques have been applied to characterize the developed thin-film nanocomposite membranes such as Fourier transform infrared (FTIR) microscopy, field emission scanning electron microscopy (FESEM), X-ray powder diffraction (XRD), and contact angle measurement to examine the presence of vibrational modes, surface morphology, the crystal structure of nanoparticles, and hydrophilicity of the membrane, respectively. Membrane properties include porosity, salt rejection, mean pore radius, pure water flux, and industrial effluent rejection efficiency that were studied. The thin-film nanocomposite membrane T5-PES@TiO2(2%)-ZnO(0.3%) was prepared with a combination of 17 wt% PES, 78 wt% DMF, 3 wt% PVP K30, 2% TiO2, 2.5 wt% PPD, 0.3 wt% ZnO, and 1.0 wt% TMC that exhibited high water permeability, porosity, higher industrial effluent rejection, and salt rejection efficiency compared to the neat PES membrane.