The aim of this study was to investigate the usefulness of a membrane hybrid process for the treatment of real textile wastewater (TWW) and its potential reuse in the dyeing of cotton knitted fabric ...(DCF) process. To determine a suitable pretreatment, sand filtration, coagulation, and UF hollow fiber (UF–HF) were compared on a laboratory scale in terms of turbidity, color, and total organic carbon (TOC). Here, UF-HF provided the best removal results of 93.6%, 99.0%, and 29.0%, respectively. The second stage involves the study of UF flat sheet membranes (5, 10, 20, and 50 kDa). The 5 kDa membrane provided the best permeate quality according to the chemical oxygen demand (COD), turbidity, TOC, conductivity, and color by 54.5%, 83.9%, 94.2%, and 45.7–83.3%, respectively. The final step was treatment with nanofiltration (NF) and reverse osmosis (RO) and these effluents were reused for dyeing. Finally, the effluents from UF-HF/5 kDa UF/RO (Scenario 1) and UF-HF/5 kDa UF/NF (Scenario 2) were analyzed for turbidity, COD, TOC, biological oxygen demand, conductivity, hardness, anions and cations, and color. Both scenarios provided high removal results of 76.3–83.5%, 94.6–97.7%, 88.5–99%, 95.4–98.0%, 59.2–99.0%, 88.7–98.7%, 60.7–99.1%, and 80.0–100%, respectively. They also satisfied the DCF tests compared to the standard DCF samples. The innovative aspect of this research is as follows: 1) the complete analysis of hybrid membrane separation processes for the purpose of reuse of treated textile wastewater and 2) the proposal of a new criterion for reuse for DCF.
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•Usefulness of hybrid membrane process for reuse in textile dyeing was established.•ZW-1/5 kDa UF/NF–RO showed removal efficiencies of monitored parameters of 59–100%.•High color fastness of dyed textile with ZW-1/5 kDa UF/NF permeate was achieved.•New reuse criteria for dyeing cotton knitted fabric were proposed.•Treatment ZW-1/5 kDa UF/NF shows the better economic efficiency of 395.656,00 €.
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•Ozonation (O3) and electrocoagulation (EC) work well in a salty wastewater matrix.•EC-O3 treatment gives more than 95% color removal in a very short time (18 min).•Ozone dose can be ...reduced more than 5 times when EC is coupled with O3 treatment.•Two-step EC → O3 treatment was more economically justified.•Recycling of purified brine in a subsequent dyeing operation gave very promising results.
Industrial textile wastewater is usually characterized by high pH, intense color and extremely high salinity, especially in case of wastewater generated after dyeing. Due to the complex matrix of textile wastewater, the selection of an appropriate treatment method can be a challenge. This paper presents the advantages of coupling electrocoagulation (EC) and ozonation (O3) as one-step (EC + O3) and two-step (EC → O3) operations. The combination of EC and O3, which both worked well in salty environment, gave very good results in the case of aqueous solutions and real industrial wastewater containing Reactive Black 5 (RB5). Very high color removal, more than 95%, was achieved in a very short treatment time (less than 18 min, while ca. 60 min was required in the case of individual O3). At the same time the applied ozone dose was reduced from 1.69 g/L, when using O3 only, to less than 0.3 g/L for EC → O3. The results of color removal and mineralization analysis indicated the high efficiency of both the EC + O3 and EC → O3 processes; however, the cost evaluation revealed that the EC → O3 treatment was more advantageous. EC preformed as a single treatment resulted in an increase in toxicity, but coupling EC with O3 reduced this undesirable effect. Very promising results were obtained in recycling trials. The color difference (DEcmc, according to ISO 105-J03) of textiles dyed with purified wastewater (brine) were between 0.28 and 0.98 (below the limiting value of 1.5).
This study focused on the removal of biological oxygen demand (BOD) and chemical oxygen demand (COD) from textile waste effluents using activated carbon prepared from sugarcane bagasse (SBAC). ...Various techniques including XRD, SEM, BET and FTIR were done to characterize the SBAC. The three independent process variables, SBAC dose, pH and reaction time were selected to develop mathematical models for BOD and COD removal efficiency using response surface methodology (RSM). The predicted models were statistically optimized to maximize BOD and COD removal. The optimal values were predicted to be a SBAC dose of 0.915 g/L, pH of 3.225, and a reaction time of 98.91 min for maximized BOD and COD removal efficiencies of 0.0225 and 0.023 mg/L min−1, respectively. Using these optimal values, kinetics studies from the experimental data showed that the rate constants for BOD and COD removal were 0.028 and 0.0274 mg/L min−1, respectively.
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•Sugarcane bagasse derived activated carbon was prepared.•Activated carbon was used for BOD and COD removal from textile effluents.•Prepared activated carbon was characterized by XRD, SEM, BET, and FTIR.•Response surface model for BOD and COD removal were developed.•Adsorbent dose, pH and reaction time were optimized.
It is evident from many recent papers that release of colored wastewater into the environment is source of pollution and this is a problem that particularly affect textile, dyeing and food ...industries. The review: (i) presents an analysis of various mechanisms involved in the different processes for color removal; (ii) describes conveniences and disadvantages that may exist in adopting one type of treatment in spite of another; (iii) reports the results of approximately 180 experimental tests. Both examples of treatments already widely applied to the real scale and still in the experimental phase are reported. This work focuses on different types of chemical/physical, chemical, electrochemical and biological processes applied in the field of color removal from industrial wastewater. Common chemical/physical treatments such as coagulation/flocculation, adsorption and membrane filtration as well as chemical-type processes are discussed, both those that exploit the traditional oxidizing chemical agents such as Ozone, H2O2 and reactive based on chlorine and those based on the principle of advanced chemical oxidation. In particular, both Hydroxyl radical based Advanced Oxidation Processes (AOPs) and Sulfate radical based AOPs are reported. The most commonly used Electrochemical processes for the removal of color are also presented as well as biological treatments. Based on more than 200 papers, this review provides important information on the use, effectiveness, advantages and downsides of the various treatments aimed at removing the color from the wastewater with a look at the technologies still under development.
•Wastewater color removal is a process that must be assessed on a case-by-case basis.•Chemical/physical methods are certainly still common used.•Advanced chemical oxidation processes are the most promising ones today.•Electrochemical and biological processes must still be adequately studied.
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•Generation of SO4•- via different methods, their mechanisms and oxidative pathways.•Systematically reviewed the SR-AOPs based treatments of textile wastewater.•Comparison of the ...performance of SR-AOPs and other •OH radicals based AOPs.•Studies on the pilot-scale and the full-scale applications of SR-AOPs are summarized.
The global textile industry is an ever-growing market, and the multi-stage operations of the textile manufacturing process produce an enormous quantity of wastewater encompassing refractory organic chemicals, necessitating the efficient, scalable, and economically viable advanced treatment methodologies. Among other advanced oxidation processes (AOPs), sulfate radicals based AOPs (SR-AOPs) gaining much attention in removing wide range of persistent organics in recent years, owing to its efficacy, adaptability, and versatility. SR-AOPs possess series of advantages over •OH radicals based AOPs such as high reactivity in wider pH range, selectivity towards contaminants, and numerous methods to activate its precursors persulfate (PS, S2O82−) and peroxymonosulfate (PMS, HSO5−) to produce sulfate radicals (SO4•-). In this review, the following aspects of the SR-AOPs are discussed for treating the textile wastewaters. (a) different methods and its mechanisms of PS and PMS activation including (i) homogenous and heterogenous metal activated processes such as metal ions, zero valent metals, metal oxides/ sulfides, and, metal organic frameworks, (ii) energy activated processes such as radiation (ultraviolet (UV), ultrasound (US) and microwave), and thermal activation, (iii) electrochemical based activation and (iv) carbocatalysis are discussed, (b) various reactive molecules and radicals species formed during the activation of PS and PMS, and its oxidative pathways and reactivities are elaborated, (c) performance of various SR-AOPs in treating textile wastewaters under different operating conditions, wastewater compositions and other influencing factors are deliberated, (d) comparison of the performances of SR-AOPs over HO• radicals based AOPs is discussed in treating the textile wastewaters and, (e) studies on the pilot-scale and the full-scale applications of SR-AOPs are summarized.
•Review of AOPs and biological processes in industrial textile wastewater treatment.•Analysis of single and combined processes.•Integration of chemical and biological oxidation improves pollutants ...degradation.•Industrial application examples of textile wastewater treatment in Poland.
The textile industry is known as releasing huge amounts of wastewater contaminated by a large spectrum of chemicals. There are several units (e.g. printers, mercerizing machines, finishing machines, dyers) within a dye house that generate different types of effluents, some of which (mostly dyers) work in batch mode. As a result, the wastewater composition varies significantly in concentration and time. Due to this, textile wastewater treatment can be very complicated. The recent trend in the textile industry is on-site wastewater treatment and the process water recycling. This review paper presents the recent developments in Advanced Oxidation Processes (AOPs), biological processes and their combinations for industrial textile wastewater. Most studies only investigated the mixed wastewater originating from the plants, without a deeper consideration on the effluents generated by different units within the dye house. Due to an extreme variation of the textile wastewater quality, the strategy of the division of the wastewater into separated streams according to their biodegradability is highly recommended. Particular attention has been paid in this review to the comparison of cost effectiveness of wastewater treatment processes. The presented considerations are based not only on a literature survey of the last 20 years but also on exemplified industrial cases of the application of AOPs and biological process in textile factories in Poland.
•Graphite/β-PbO2 anode was used to improve the biodegradability of textile wastewater.•Process optimization by genetic algorithm.•Electrochemical degradation mechanism of methylene blue.•Reusability ...and stability of graphite/β-PbO2 anode was investigated.
An anodic oxidation process with graphite anode coated with lead dioxide (G/β-PbO2) was optimized for the degradation of methylene blue (MB) and the treatment of real textile wastewater. The G/β-PbO2 anode was prepared by the electrochemical precipitation method. The scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD) analyses confirmed the successful coating of graphite substrate with the β-PbO2 film. The effect of four independent variables including pH, reaction time, current density, and electrolyte concentration of Na2SO4 on the performance of the electrochemical oxidation system was modeled by using a complete central composite design and was then optimized by genetic algorithm method. The accuracy of the proposed quadratic model by CCD was confirmed with p-value <0.0001 and adj-R2 > 0.9. The optimum conditions for solution pH, reaction time, current density, and Na2SO4 electrolyte concentration were obtained to be 5.75, 50 min, 10 mA/cm2, and 78.8 mg/L, respectively. In these conditions, the experimental removal efficiencies of MB using G/β-PbO2 and graphite anodes were 96.2% and 68.3%, respectively. The electrochemical removal of MB using both G/β-PbO2 and graphite anodes wellfollowedthepseudo-first-order reaction (R2 > 0.9). Cyclohexane, cyclohexa-2,5-dien-1-ylium, and N-(sec-butyl) aniline were the most abundant intermediates identified by LC-MS analysis. However, the complete mineralization of MB was achieved in 60 min. The optimized anodic oxidation process successfully improved the biodegradability of real textile wastewater (BOD/COD>0.4).
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•The PSF/GO loose NF hollow fiber membranes were fabricated by one-step NIPS method.•Air was used as bore fluid to eliminate the double diffusion in the inner surface.•The membranes ...exhibited excellent separation performance for textile wastewater.
In this work, we reported the fabrication of novel loose nanofiltration (NF) hollow fiber membranes with dense-loose structure by one-step non-solvent induced phase separation (NIPS) method without post treatment. We selected air and graphene oxide (GO) as bore fluid and additive, respectively. The effects of air and GO on the properties of the prepared membranes were investigated based on field emission scanning electron microscope (SEM) image, pore size distribution, differential scanning calorimetry (DSC), Raman spectra, X-ray photoelectron spectrometer (XPS), water contact angle, zeta potential, mechanical strength, permeability, and rejection. The prepared membranes presented a long-term stability with a high dye rejection of 99.9% for treating the simulated textile wastewater. Meanwhile, the flux was much higher than those of the other reported membranes. Therefore, our prepared membranes showed a great potential for treating textile wastewater.
The synthetic dyes used in the textile industry pollute a large amount of water. Textile dyes do not bind tightly to the fabric and are discharged as effluent into the aquatic environment. As a ...result, the continuous discharge of wastewater from a large number of textile industries without prior treatment has significant negative consequences on the environment and human health. Textile dyes contaminate aquatic habitats and have the potential to be toxic to aquatic organisms, which may enter the food chain. This review will discuss the effects of textile dyes on water bodies, aquatic flora, and human health. Textile dyes degrade the esthetic quality of bodies of water by increasing biochemical and chemical oxygen demand, impairing photosynthesis, inhibiting plant growth, entering the food chain, providing recalcitrance and bioaccumulation, and potentially promoting toxicity, mutagenicity, and carcinogenicity. Therefore, dye-containing wastewater should be effectively treated using eco-friendly technologies to avoid negative effects on the environment, human health, and natural water resources. This review compares the most recent technologies which are commonly used to remove dye from textile wastewater, with a focus on the advantages and drawbacks of these various approaches. This review is expected to spark great interest among the research community who wish to combat the widespread risk of toxic organic pollutants generated by the textile industries.
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•Textile dyes are toxic and discharged as effluent into the aquatic environment.•Non-pretreated effluent has significant negative impacts on living microorganisms.•Dye-containing wastewater should be effectively treated using eco-friendly methods.•Combined approaches and recent technologies are promising for dye removal.•More research is required until an advanced, zero-waste process is established.
Plants are known to remediate dyes, metals and emerging contaminants from wastewaters. Vetiveria zizanioides, a perennial bunchgrass showed removal of Remazol Red (RR, 100 mg/L) up to 93% within ...40 h. Root and shoot tissues of V. zizanioides revealed induction in dye degrading enzymes viz. lignin peroxidase by 2.28 and 1.43, veratryl alcohol oxidase 2.72 and 1.60, laccase 6.15 and 3.55, and azo reductase 2.17 and 2.65-fold, respectively, during RR decolorization. Substantial increase was observed in the contents of chlorophyll a, chlorophyll b, and carotenoids in the plant leaves during treatment. Anatomical studies of roots, HPLC and GC-MS analysis of metabolites, and phytotoxicity assessment confirmed phytotransformation of RR into nontoxic metabolites. Floating phytobed with V. zizanioides treated textile wastewater (400 L) effectively and reduced ADMI, COD, BOD, TDS, and TSS by 74, 74, 81, 66 and 47%, respectively within 72 h. In-situ treatment of textile wastewater for 5 days in constructed furrows planted with semiaquatic plants, V. zizanioides, Ipomoea aquatica and its consortium-VI decreased ADMI by 68, 61 and 76%, COD by 75, 74 and 79%, BOD by 73, 71 and 84%, TDS by 77, 75 and 83%, and TSS by 34, 31 and 51%, respectively. This treatment was also useful to remove arsenic, cadmium, chromium and lead from wastewater. Overall observation suggests wise strategy to use this plantation in the furrows of high rate transpiration system and phytobeds in deep water for textile wastewater treatment.
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•Remazol Red, dye mixture and textile effluent treated efficiently by V. zizanioides.•Histological analysis confirmed entry and degradation of dyes in roots.•Floating phyto-bed reactor treated textile wastewater effectively.•Textile wastewater was noteworthily treated in plant cultivated furrows of HRTS.•Plant consortium enhanced the potential of textile dye removal.
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