scholarly journals A prototype of textile wastewater treatment using coagulation and adsorption by Fe/Cu nanoparticles: Techno-economic and scaling-up studies

2021 ◽  
Vol 11 ◽  
pp. 184798042110411
Author(s):  
Ahmed S Mahmoud ◽  
Mohamed K Mostafa ◽  
Robert W Peters

This study aims to investigate the efficiency of a pilot prototype system comprising coagulation/flocculation, filtration, and nano-bimetallic iron/copper (Fe/Cu) degradation and adsorption units for the removal of chemical oxygen demand (COD), biological oxygen demand (BOD), color, total nitrogen (TN), total phosphorus (TP), and TSS from real textile wastewater. The total removal efficiencies of the system were 96, 98, 82, 69, 88, and 97%, respectively, using 0.5 g/L ferric chlorides as a coagulant under an optimum adsorption condition of pH 6.0, nano-dosage 1.4 g/L, contact time 80 min, and stirring rate 250 r/min at room temperature. Adsorption isotherms indicated that the removal of COD and TP obeys both Koble–Corrigan and Freundlich adsorption models, removal of color obeys both Koble–Corrigan and Hill adsorption models, and removal of TN and TSS obeys Koble–Corrigan and Khan models, respectively. Avrami kinetic models adequately describe the adsorption data for COD, BOD, TN, and TSS, while pseudo-second-order and intraparticle models described the removal mechanism of color and TSS, respectively. An artificial neural network (ANN) with r2-value exceeding 0.98 is accurate and can be used with confidence in predicting removal efficiencies of the targeted parameters. Sensitivity analysis results showed that the initial concentration was the most influential parameter for TSS removal with relative importance greater than 25%, while the bimetallic Fe/Cu dosage was the most influential factor for all other studied parameters with relative importance greater than 40%. The total treatment cost of the proposed system per m3 after scaling up was found to be US$4.5 for reuse of the treated water for the irrigation of forest trees.

2018 ◽  
Vol 13 (3) ◽  
pp. 495-504 ◽  
Author(s):  
Amare Tiruneh Adugna ◽  
Nahom Mankir Gebresilasie

Abstract This study focused on the evaluation of Aloe steudneri gel for textile wastewater clarification with identification of major phytochemical groups and physicochemical characteristics of Aloe steudneri. Optimization of pH, flocculant dose, mixing speed and time were studied for Aloe steudneri gel and synthetic polyacrylamide. A jar test was used to perform the flocculation at optimum conditions (pH 7.3, flocculant dose 33 ml, mixing time 20 minutes and speed 61 rpm). Phytochemical groups like tannins, flavonoids and saponins were identified and the gel showed a good result of 1.9 g H2O/dry polymer for swelling capacity and 6.2 g oil/weight for fat adsorption capacity. At the optimum conditions, the turbidity removal was 92.3% for Aloe steudneri gel and 92.7% for polyacrylamide. Moreover, the removal efficiencies for chemical oxygen demand, 5-day biological oxygen demand, total suspended solids and lead were 76.8%, 83.5%, 57.9% and 77% for Aloe steudneri gel and 78%, 89%, 51% and 72% for polyacrylamide, respectively. Therefore, it is possible to conclude that Aloe steudneri gel can substitute the polyacrylamide as there are no significant differences in their removal efficiencies.


Author(s):  
Fagbenro Oluwakemi Kehinde ◽  
Salem S. Abu Amr ◽  
Hamidi Abdul Aziz

As textile and dyeing industries increase, pollution due to effluent discharges from the same industries also increase and become of great concern to a healthy environment. In an attempt to understand the generation and treatment of textile wastewater, this chapter discusses the processes from which textiles are made, items of importance that are used in the production process which may account for the characteristics of the wastewater and persulfate, applied in the treatment of textile wastewater. Although these wastewaters are generally characterized by color, fluctuating pH, heat, salts, suspended solids (SS), the presence of metal ions, biological oxidation demand (BOD), and chemical oxygen demand (COD), color is the most obvious. The presence of color in the effluents from textile dyeing and finishing is due to the inefficient dyeing processes, resulting in unfixed forms of the dyestuff. To achieve the primary objective of obtaining a clean environment, there is a need for continuous monitoring of textile wastewater discharges, of which major concern is color.


2018 ◽  
Vol 20 (3) ◽  
pp. 449-457

<p>This study explored the best-operating conditions for a novel electrocoagulation (EC) reactor with the rotating anode for textile wastewater treatment. The influence of operating parameters like inter-electrode distance (IED), current density (CD), temperature, pH, operating time (RT), and rotation speed on the removal efficiency of the contaminant was studied. A comparative study was done using conventional model with static electrodes in two phases under same textile wastewater The findings revealed that the optimal conditions for textile wastewater treatment were attained at RT = 10 min, CD = 4 mA/cm2, rotation speed = 150 rpm, temperature = 25oC, IED = 1cm, and pH = 4.57. The removal efficiencies of colour, biological oxygen demand (BOD), turbidity, chemical oxygen demand (COD), and total suspended solid (TSS) were 98.50%, 95.55%, 96%, 98% and 97.10% within the first 10 min of the reaction. The results of the experiment reveal that the newly designed reactor incorporated with cathode rings and rotated anode impellers provide a superior treatment efficiency within a short reaction time. The novel EC reactor with a rotating anode significantly enhanced textile wastewater treatment compared to the conventional model. The values of adsorption and passivation resistance validated the pollutants removal rate.</p>


2017 ◽  
Vol 76 (9) ◽  
pp. 2515-2525 ◽  
Author(s):  
Edison GilPavas ◽  
Paula Arbeláez-Castaño ◽  
José Medina ◽  
Diego A. Acosta

Abstract A combined electrocoagulation (EC) and electrochemical oxidation (EO) industrial textile wastewater treatment potential is evaluated in this work. A fractional factorial design of experiment showed that EC current density, followed by pH, were the most significant factors. Conductivity and number of electrooxidation cells did not affect chemical oxygen demand degradation (DCOD). Aluminum and iron anodes performed similarly as sacrificial anodes. Current density, pH and conductivity were chosen for a Box–Behnken design of experiment to determine optimal conditions to achieve a high DCOD minimizing operating cost (OC). The optimum to achieve a 70% DCOD with an OC of USD 1.47/m3 was: pH of 4, a conductivity of 3.7 mS/cm and a current density of 4.1 mA/cm2. This study also shows the applicability of a combined EC/EO treatment process of a real complex industrial wastewater.


2020 ◽  
Vol 1 (2) ◽  
pp. 40-43
Author(s):  
Tran Thanh Đat ◽  
Trinh Trong Nguyen ◽  
Thai Van Nam

Using natural coagulants derived from available and popular plants ensures the quality of wastewater discharged, saving costs for businesses, environmentally friendly. SEM results show that surface of the material is rough with the multi-layered structure that increases the contact areas, deep holes with undefined shapes on materials will increase diffusion and absorption of dirty residues of different sizes. To investigate the effectiveness of textile wastewater treatment by dried Nopal Cactus powder, the Jartest model was used to identify the best parameters for handling color levels and chemical oxygen demand (COD) treatment of artificial wastewater sources. Jartest experiment identified the best values for removing color levels and COD: pH = 3, dried Nopal Cactus powder amount of 100mg/L, stirring velocity of 40 rpm; stirring time of 10 minutes. The efficiency of processing color levels and COD with the best parameters are 87.85% and 60.21%, respectively. Regarding the efficiency of processing textile wastewater, there shows an average color reduction efficiency (52.89%), low-level COD treatment (25.56%). Optimal result: with dyeing textile wastewater sample, the input COD value is 260 mg/L, the color level is 470Pt-Co. The experiment with 36 test modes is run by STAGRAPHIC XV software and analyzed by ANOVA combination of 2 variables COD and color levels, the results with the highest performance for the color level and COD are 77.07% and 59.11% respectively. The optimal pH value is 2.6, the amount of dried Nopal Cactus powder is 80 mg/L, stirring velocity is 40.0 rpm, the time is 8.2 minutes


1994 ◽  
Vol 30 (3) ◽  
pp. 255-263 ◽  
Author(s):  
Frank Gähr ◽  
Frank Hermanutz ◽  
Wilhelm Oppermann

The German textile industry is challenged by the introduction of new governmental regulations in the field of textile wastewater treatment This causes a large increase of water costs in comparison with other European countries. Many economic experts even see Germany seriously endangered as a place of textile production, however there are also opportunities with the development of high performance cleaning technologies as a result of these governmental measures. In particular the required separate treatment of selected wastewaters of different fmishing processes bas some good perspectives since specialized wastewater techniques can be applied efficiently. For instance the separation of unfixed reactive dyes is the ideal basis for ozone oxidation. Ozonation being a sludge-free method to decompose dyestuff, fmishing products, and other organic materials is of increasing importance because of the limited space for disposal of sludges. Other advantages of ozone treatment are the improvement of biodegradability, reduction of aromatic and halogenated organic compounds and also a significant decrease of chemical oxygen demand. The ozonation of textile wastewaters in combination with inexpensive biological processes has the potential to play a major role in the future. Partial replacement of coagulation/precipitation can be expected.


2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Harun Akif Kabuk ◽  
Yasar Avsar ◽  
S. Levent Kuzu ◽  
Fatih Ilhan ◽  
Kubra Ulucan

This study investigated the biological treatability of textile wastewater. For this purpose, a membrane bioreactor (MBR) was utilized for biological treatment after the ozonation process. Due to the refractory organic contents of textile wastewater that has a low biodegradability capacity, ozonation was implemented as an advanced oxidation process prior to the MBR system to increase the biodegradability of the wastewater. Textile wastewater, oxidized by ozonation, was fed to the MBR at different hydraulic retention times (HRT). During the process, color, chemical oxygen demand (COD), and biochemical oxygen demand (BOD) removal efficiencies were monitored for 24-hour, 12-hour, 6-hour, and 3-hour retention times. Under these conditions, 94% color, 65% COD, and 55% BOD removal efficiencies were obtained in the MBR system. The experimental outputs were modeled with multiple linear regressions (MLR) and fuzzy logic. MLR results suggested that color removal is more related to COD removal relative to BOD removal. A surface map of this issue was prepared with a fuzzy logic model. Furthermore, fuzzy logic was employed to the whole modeling of the biological system treatment. Determination coefficients for COD, BOD, and color removal efficiencies were 0.96, 0.97, and 0.92, respectively.


2018 ◽  
Vol 14 (2) ◽  
pp. 257-262
Author(s):  
Mohd Fahmi Muhammad Mubarak ◽  
Muhamad Hanif Md Nor ◽  
Muhamad Firdaus Sabaruddin ◽  
Hui Han Bay ◽  
Chi Kim Lim ◽  
...  

One of the most abundant dyes that are used extensively in the textile manufacturing are azo dyes, which may endanger water bodies since incomplete breakdown of dyes may cause mutagenic and carcinogenic compounds to persist. In this study, BAC-ZS, bacterial mixed culture consisting of three acclimatised decolourising bacteria were grown as biofilm onto macrocomposites. Different time duration between 3 to 14 days of biofilm development was studied to determine the density of biofilm attached onto macrocomposites. Sequencing batch reactors (SBRs) were set up for raw textile wastewater treatment to investigate the effectiveness of the treatment with and without the presence of biofilm (control). The treatment was performed under facultative anaerobic-aerobic condition for 20 days continuously with 48-hour of hydraulic retention time (HRT) cycle (consisting both conditions). Colour and chemical oxygen demand (COD) were monitored throughout the treatment process. Results showed that the colour and COD removal by the developed biofilm were 78.6 ± 1.4% and 76.4 ± 1.12% from initial values of 1400 ADMI and 660 mg/L, respectively while only 47.9 ± 0.9% colour and 38.0 ± 1.5% COD removal for the control. In conclusion, the biofilm of BAC-ZS mixed culture coated onto macrocomposites showed potential applications in the treatment of raw textile wastewater.


2018 ◽  
Vol 54 (4B) ◽  
pp. 64
Author(s):  
Nga Thi Dinh

This study investigated the Photo-Fenton process in textile wastewater treatment by using textile synthesis wastewater made of Symafix Red Dye solution. The aim of the study was to investegate the factors that influent to the photo-Fenton process such as contact time, pH, H2O2 and Fe2+conectrations, and UVexposure in order to research the optimum values of this process.Treatment of textile wastewater was carried out at ambient temperature in a batch reactor. As a result, the second-order is suitable for the reaction of removing color by using Photo –Fenton processes. The removal efficiencies decreased when we increased the concentration of Fe2+ from 7.162 mM to 14.162 mM. When we increased the H2O2 concentration from 0.037 mM to 0.11mM, the removal efficiencies slightly decreased. The optimum value of pH is pH = 3. At the optimum of pH value and minimum the concentration of Fe2+ and H2O2 the removal efficiency could reach up to 95.82 %. 


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