Textile Wastewater Reuse Research Articles

Combined electrocoagulation/flotation technique and membrane desalination for textile wastewater reuse

A novel integrated system that combined electrocoagulation/flotation (ECF) technique with membrane desalination was used for textile wastewater treatment to reduce the environmental pollution of textile wastewater. Two scenarios were examined: the first is ECF followed by membrane desalination; the second is the application of membrane desalination for treatment of raw wastewater. Iron electrodes were used in batch-wise tests to examine the effects of electrolysis time and current intensity on percentage removals. The SiO2/PA(TFC) membrane was used to treat raw wastewater and ECF effluents. As the current intensity increased from 50 mA to 600 mA, the color elimination was improved from 94 % to 99 % and the COD elimination improved from 59.1 % to 81.5 %. The findings demonstrate the efficacy of ECF in removing color and COD, although the treated wastewater sample's TDS increased from 4200 mg/L to 19,400 mg/L (raw textile wastewater sample). The SiO2/PA(TFC) membrane displays the salt rejection and water flux reduction of the raw wastewater samples 95 %, and 22 (L/m2.h). Corresponding results for ECF treated wastewater were 94, 93, 91 % and 13, 11.5, and 10 (L/m2.h), respectively. The SiO2/PA(TFC) membrane displays the reduction of COD from 760 mg O2/L (raw) and 310 mg O2/L (ECF effluent) to zero%. Also, it proves the capabilities of SiO2/PA(TFC) membrane for the removal of TDS, COD and color. This integrated system can provide sustainable source for fresh water supply used for landscape, irrigation, industry and various purposes.

Groundwater conservation, and recycling and reuse of textile wastewater in a denim industry of Bangladesh

Bangladesh holds the 2nd position after China in the global apparel market in terms of denim export. In the textile industry clusters of Bangladesh, the groundwater level is depleting at an alarming rate due to overconsumption and mismanagement. The present study evaluates the groundwater conservation potential of a denim facility in Manikganj District through an effluent recycling and reuse approach. In this study, 100% treated wastewater and 10% treated wastewater mixed with softwater were utilized in the wet processing plant to dye and wash sample denim products and investigated for their fabric quality using seven parameters. The test results followed the requirements given by the North American and European fashion brands that source denim products from Bangladesh. The feasibility assessment of groundwater conservation through its high (100%) and low (10%) recycling rates indicated that the studied facility can potentially save around 619,230 m3 and 61,923 m3 of groundwater in a year, respectively.

The study of optimal ozone dose for industrial ozone installation in textile wastewater reuse

The study of optimal ozone dose for industrial ozone installation in textile wastewater reuse

Comprehensive Meta-Analysis of Pathways to Increase Biogas Production in the Textile Industry

The textile industry is one of the largest environmental polluters in the world. Although waste management via anaerobic digestion (AD) is a sustainable strategy to transform waste into clean energy and water recovery, the efficiency of the AD process is reduced by the presence of recalcitrant materials, chemicals, and toxic contents. This study aims to investigate the performance of several chemical, physical, and biological pretreatments applied to improve the biodegradability of textile waste. We performed a meta-analysis with 117 data extracted from 13 published articles that evaluated the efficiency of pretreatments applied to textile waste prior to AD to increase biogas production measured as methane (CH4) yield. Even though the majority of the studies have focused on the effect of chemical and physical pretreatments, our results showed that the application of biological pretreatments are more efficient and eco-friendlier. Biological pretreatments can increase CH4 yield by up to 360% with lower environmental risk and lower operating costs, while producing clean energy and a cleaner waste stream. Biological pretreatments also avoid the addition of chemicals and favor the reuse of textile wastewater, decreasing the current demand for clean water and increasing resource circularity in the textile industry.

Reuse of textile wastewater for dyeing cotton knitted fabric with hybrid treatment: Coagulation/sand filtration/UF/NF-RO

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.

Environment -friendly processes: Electrocoagulation and Activated carbon filtration for reuse of textile wastewater

Electrocoagulation is a simple method used for removing contaminants and recycling wastewater by using aluminum, stainless steel and iron electrodes. Textile wastewater was collected from the textile processing industry. This promising treatment consists of two steps, electrocoagulation as a first step completed with Activated carbon filtration as a second step reported in this work. The contaminants of the solution combined in the situ forming metal hydroxide flocs, which filtered as a precipitate or skimmed as a float. To revenue the best advantage of this system, the two processes should run in a rational sequence. Several important parameters, such as applied potential, Electrode material and conductivity were studied to achieve higher removal efficiency. Scanning electron microscope (SEM) analysis, Atomic force microscopy (AFM) and the electrical connection of electrodes were investigated. The results showed clearly that the stainless steel electrode can enhance effectively color removal by 98.8 %, reduced COD to 256 mg /L, while Activated carbon filtration can almost remove the total dissolved solids (TDS) and, turbidity. The findings showed that in textile wastewater at pH=10.5 the stainless steel is superior to iron and aluminum as a sacrificial electrode material and Mono-polar Connection in Parallel is the best connection as it decreases the potential difference, and energy Consumption was 2.5 kWh/m3.

Reuse of textile wastewater treated by moving bed biofilm reactor coupled with membrane bioreactor

AbstractA laboratory‐scale pilot plant of moving bed biofilm reactor coupled with membrane bioreactor (MBBR‐MBR) was studied with regard to wastewater treatment in the textile industry, and the reuse feasibility of treated water was investigated. The pilot plant comprised two connected parts: an aerobic tank filled with carriers and a submerged membrane tank. The MBBR‐MBR system reduced the hydraulic retention time to 1 day, which is very promising compared with conventional biological treatment in the textile industry. The removal efficiency of chemical oxygen demand reached 93%, which is almost the maximum for a biological process treating this type of wastewater, as well as the colour removal performance, which achieved 85%. Additionally, 99% of total suspended solids were removed due to filtration. Furthermore, new dyeing processes reusing the treated water were performed. The quality of the new dyed fabrics with treated water was compared with reference fabrics. Colour differences between new dyed fabrics and reference fabrics were found to be within the general requirement of the textile industry (ΔECMC(2:1) < 1). The reuse of treated water in new dyeing processes is beneficial both for the industry and for the environment, because the textile sector is an intensive water consumer during both the dyeing and finishing processes.

In-situ synthesis of PA/PVDF composite hollow fiber membranes with an outer selective structure for efficient fractionation of low-molecular-weight dyes-salts

A polyamide/poly(vinylidene fluoride) composite hollow fiber membrane (HFM) was designed by in situ interfacial polymerization (IP) during the fiber spinning process. Using a piperazine aqueous solution as the bore fluid and a dual-bath coagulation, the PA outer layer was formed via IP of the PIP in the bore fluid and TMC in the second reactive bath during phase inversion process. Chemical structure, membrane morphology and surface property were characterized by using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscope (XPS), scanning electron microscope (SEM), and zeta potential. The effects of several parameters involved in the membrane fabrication (e.g., piperazine concentration, bore fluid flow rate, residence time and heat treatment temperature) on the morphology and performance of resultant composite HFMs were investigated. The composite HFM showed a performance that is comparable favorably with conventional nanofiltration membranes in terms of showed water permeability (10.2 L/m2·h·bar), high rejection to dyes (i.e., 100% for CR and EBT, 99.99% for RhB and MB, 98.3% for MO) and low salt rejections (NaCl 6.2%). Moreover, the newly developed composite HFM showed good stability and flux recovery with simple water rinsing for treatment of simulated textile wastewater. This work is expected to provide a new approach to designing composite HFMs for the treatment and reuse of textile wastewater.

Niobium Oxide Catalysts as Emerging Material for Textile Wastewater Reuse: Photocatalytic Decolorization of Azo Dyes

Niobium-based metal oxides are emerging semiconductor materials with barely explored properties for photocatalytic wastewater remediation. Brazil possesses the greatest reserves of niobium worldwide, being a natural resource that is barely exploited. Environmental applications of solar active niobium photocatalysts can provide opportunities in the developing areas of Northeast Brazil, which receives over 22 MJ m2 of natural sunlight irradiation annually. The application of photocatalytic treatment could incentivize water reuse practices in small and mid-sized textile businesses in the region. This work reports the facile synthesis of Nb2O5 catalysts and explores their performance for the treatment of colored azo dye effluents. The high photoactivity of this alternative photocatalyst makes it possible to quickly obtain complete decolorization, in less than 40 min of treatment. The optimal operational conditions are defined as 1.0 g L−1 Nb2O5 loading in slurry, 0.2 M of H2O2, pH 5.0 to treat up to 15 mg L−1 of methyl orange solution. To evaluate reutilization without photocatalytic activity loss, the Nb2O5 was recovered after the experience and reused, showing the same decolorization rate after several cycles. Therefore, Nb2O5 appears to be a promising photocatalytic material with potential applicability in wastewater treatment due to its innocuous character and high stability.

Life Cycle Comparison of Membrane Capacitive Deionization and Reverse Osmosis Membrane for Textile Wastewater Treatment

The reduced natural water sources on the one hand and the large amount of wastewater produced by the textile industry on the other hand lead to the requirement of an effective reuse of textile wastewater. In this study, the treatment of textile wastewater by the reverse osmosis membrane system and membrane capacitive deionization (MCDI) system has been investigated to improve the quality and the recovery rate of the effluent for reclamation. The maximum chemical oxygen demand (COD) removal efficiency obtained at 10 bar was 96.3% for BW30 reverse osmosis membrane. Diversified operating conditions, including working voltage and flow rate, were investigated systematically in the MCDI system which is an effective water purification technology. According to the obtained experimental results, the COD removal efficiency was thoroughly increased by rising the working voltage (from 0.2 to 1.2 V) and the flow rate (from 5 to 17.5 ml/min). The flow rate and the working voltage at which the COD from textile wastewater removal ratio was the highest were 10 ml/min and 1.2 V, respectively. A life cycle approach has also been implemented for the comparison of environmental impact assessment of the two desalination systems. In this study, a life cycle approach has been implemented for the comparison of environmental friendly impact assessment of the two desalination systems. It is concluded that MCDI system is much more environmental friendlier with 5641 times less values for damage assessment categories, on average.

Reuse of Textile Wastewater After Treating with Combined Process of Chemical Coagulation and Electrocoagulation

Reuse of Textile Wastewater After Treating with Combined Process of Chemical Coagulation and Electrocoagulation

Poly(vinylidene fluoride) hollow fiber membrane for high-efficiency separation of dyes-salts

A poly(vinylidene fluoride) hollow fiber membrane (HFM) was fabricated through a simple, fast (one-step), and inexpensive procedure to separate dyes and salts (sodium sulfate, sodium chloride) in textile wastewater. Scanning electron microscopy images of the HFM indicated that a neat hollow structure was obtained through a single shot spinneret. Moreover, the finger-like and sponge-like structure of the HFM had a hierarchical structure. The optimized HFM had a molecular weight cut off of 6798 Da and an isoelectric point of 3.8. Charge of the HFM was greater than −50 mV when the pH was higher than 6. The HFM displayed a pure water flux of 13.51 L/m2 ·h· bar, and rejection of 100% to Congo red at a dye concentration of 50 ppm and operation pressure of 0.2 MPa. The membrane also showed excellent stability and antifouling property during long-term operation with a mixture of dyes and salts. The HFM displayed efficient and stable separation performance for separation of salts and dyes, which would be of great significance for the reuse of textile wastewater.

Coupling of electrocoagulation and ozone treatment for textile wastewater reuse

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).

Application of solar photo-Fenton toward toxicity removal and textile wastewater reuse.

Solar photo-Fenton represents an innovative and low-cost option for the treatment of recalcitrant industrial wastewater, such as the textile wastewater. Textile wastewater usually shows high acute toxic and variability and may be composed of many different chemical compounds. This study aimed at optimizing and validating solar photo-Fenton treatment of textile wastewater in a semi-pilot compound parabolic collector (CPC) for toxicity removal and wastewater reclamation. In addition, treated wastewater reuse feasibility was investigated through pilot tests. Experimental design performed in this study indicated optimum condition for solar photo-Fenton reaction (20mgL-1 of Fe2+ and 500mgL-1 of H2O2; pH 2.8), which achieved 96% removal of dissolved organic carbon (DOC) and 99% absorbance removal. A toxicity peak was detected during treatment, suggesting that highly toxic transformation products were formed during reaction. Toxic intermediates were properly removed during solar photo-Fenton (SPF) treatment along with the generation of oxalic acid as an ultimate product of degradation and COS increase. Different samples of real textile wastewater were treated in order to validate optimized treatment condition with regard to wastewater variability. Results showed median organic carbon removal near 90%. Finally, reuse of treated textile wastewater in both dyeing and washing stages of production was successful. These results confirm that solar photo-Fenton, as a single treatment, enables wastewater reclamation in the textile industry. Graphical abstract Solar photo-Fenton as a revolutionary treatment technology for "closing-the-loop" in the textile industry.

Textile wastewater reuse after additional treatment by Fenton’s reagent

This study verifies textile wastewater reuse treated by the conventional activated sludge process and subjected to further treatment by advanced oxidation processes. Three alternative processes are discussed: Fenton, photo-Fenton, and UV/H2O2. Evaluation of treatments effects was based on factorial experiment design in which the response variables were the maximum removal of COD and the minimum concentration of residual H2O2 in treated wastewater. Results indicated Fenton's reagent, COD/[H2O2]/[Fe2+] mass ratio of 1:2:2, as the best alternative. The selected technique was applied to real wastewater collected from a conventional treatment plant of a textile mill. The quality of the wastewater before and after the additional treatment was monitored in terms of 16 physicochemical parameters defined as suitable for the characterization of waters subjected to industrial textile use. The degradation of the wastewater was also evaluated by determining the distribution of its molecular weight along with the organic matter fractionation by ultrafiltration, measured in terms of COD. Finally, a sample of the wastewater after additional treatment was tested for reuse at pilot scale in order to evaluate the impact on the quality of dyed fabrics. Results show partial compliance of treated wastewater with the physicochemical quality guidelines for reuse. Removal and conversion of high and medium molecular weight substances into low molecular weight substances was observed, as well as the degradation of most of the organic matter originally present in the wastewater. Reuse tests indicated positive results, confirming the applicability of wastewater reuse after the suggested additional treatment. Graphical abstract Textile wastewater samples after additional treatment by Fenton's reagent, photo-Fenton and H2O2/UV tested in different conditions.

Health risk assessment of textile effluent reuses as irrigation water in leafy vegetable Basella alba

The aim of this research was to assess the health risk of textile wastewater reuse as irrigation water on leafy vegetable (Basella alba) by comparing variable growth rate in different ration of wastewater and freshwater irrigation and assess their soil-to-plant transfer factor (TF) and health risk index (HRI). Pot experiments were laid out with five treatments including control with three replications with different irrigation schemes with textile wastewater collected from the untreated point source. The irrigation scheme was, 100 % groundwater as control with four treatments as 75 % groundwater: 25 % wastewater, 50 % groundwater: 50 % wastewater, 25 % groundwater: 75 % wastewater and 100 % wastewater. Soil-to-plant TF in different treatments including control were in the order of Pb (1.0–1.7) > Cu (1.3–1.5) > Cd (0.8–1.0) > Zn (0.1–1.1). TF values of Pb and Cu in the range from 1 to 1.7 indicating their accumulation in B. alba plants and their potential health risk by dietary exposure. The HRI for individual metal as well as cumulative HRI of the metals was less than unity (0.33) which indicated the consumption of the vegetables was considered to be safe for one harvest. Over many seasons of irrigation with wastewater, level of salinity and heavy metals can accumulate on the agriculture land and their long term consumption may link to a chronic health risk. Hence, consumption of these vegetables on regular basis should be avoided.

Optimized treatment conditions for textile wastewater reuse using photocatalytic processes under UV and visible light sources.

In this study, photo-Fenton systems using visible light sources with iron and ferrioxalate were tested for the DOC degradation and decolorization of textile wastewater. Textile wastewaters originated after the dyeing stage of dark-colored tissue in the textile industry, and the optimization of treatment processes was studied to produce water suitable for reuse. Dissolved organic carbon, absorbance, turbidity, anionic concentrations, carboxylic acids, and preliminary cost analysis were performed for the proposed treatments. Conventional photo-Fenton process achieved near 99% DOC degradation rates and complete absorbance removal, and no carboxylic acids were found as products of degradation. Ferrioxalate photo-Fenton system achieved 82% of DOC degradation and showed complete absorbance removal, and oxalic acid has been detected through HPLC analysis in the treated sample. In contrast, photo-peroxidation with UV light was proved effective only for absorbance removal, with DOC degradation efficiency near 50%. Treated wastewater was compared with reclaimed water and had a similar quality, indicating that these processes can be effectively applied for textile wastewater reuse. The results of the preliminary cost analysis indicated costs of 0.91 to 1.07 US$ m-3 for the conventional and ferrioxalate photo-Fenton systems, respectively. Graphical Abstract ᅟ.

Combination of forward osmosis (FO) process with coagulation/flocculation (CF) for potential treatment of textile wastewater

A novel combination of forward osmosis (FO) process with coagulation/flocculation (CF) (FO–CF) has been experimentally conceived for the treatment and reuse of textile wastewater. FO is employed to spontaneously recover water from the wastewater via osmosis and thus effectively reduces its volume with a dramatically enhanced dye concentration. CF is then applied to precipitate and remove dyes from the FO concentrated stream with much improved efficiency and reduced chemical dosage. The FO–CF hybrid system exhibits unique advantages of high water flux and recovery rate, well controlled membrane fouling, high efficiency, and minimal environmental impact. Using a lab-made thin-film composite (TFC) FO membrane, an initial water flux (Jw) of 36.0 L m−2 h−1 with a dye rejection of 99.9% has been demonstrated by using 2 M NaCl as the draw solution and synthetic textile wastewater containing multiple textile dyes, inorganic salts and organic additives as the feed under the FO mode. The Jw could be maintained at a high value of 12.0 L m−2 h−1 even when the recovery rate of the wastewater reaches 90%. Remarkable reverse fouling behavior has also been observed where the Jw of the fouled membrane can be almost fully restored to the initial value by physical flushing without using any chemicals. Due to the great dye concentration in the FO concentrated wastewater stream, the CF process could achieve more than 95% dye removal with a small dosage of coagulants and flocculants at 500–1000 ppm. The newly developed FO–CF hybrid process may open up new exploration of alternative technologies for the effective treatment and reuse of textile effluents.

Reuse of Textile Wastewater after Treatment with Isolated Bacteria from Oued Hamdoun River

ABSTRACTIndustrialization is a boon for developing countries such as Tunisia. However, textile effluents that are being discharged are environmental pollutants, extremely toxic to plants and other living organisms, including humans. The current study was conducted to determine the phytotoxic effect of textile effluents, collected near an industrial zone in the center of Tunisia (Ksar Helal), on the germination and various growth indices of durum wheat (Triticumaestivum L.). Results showed that textile effluent treatments reduced significantly the percentage of seed germination and slowed its kinetic as compared with control. Roots and leaves were also significantly reduced. The phytotoxicity was highly reduced from textile effluents after aerobic biotreatment with bacteria. It can be concluded that the biological treatment process of textile wastewater might serve as a fertilizer production that is able to improve the growth of plants. These results are encouraging in the context of developing a low-budget technology for the effective management of these effluents.

Reuse of textile wastewater after homogenization–decantation treatment coupled to PVDF ultrafiltration membranes

The textile industry is one of the largest consumers of water in the world and its wastewater is a serious problem when it is discharged without the proper treatment. In this work, wastewater generated by textile industry was treated coupling a homogenization–decantation treatment with polyvinylidene difluoride (PVDF) ultrafiltration membranes.Initially, the wastewater was aerated in a homogenization–decantation tank where 17% colour and 10% chemical oxygen demand (COD) were removed. The aerated effluent was treated with an ultrafiltration membrane in order to reuse the permeate in new dyeing processes. Firstly, the ultrafiltration treatment was performed in a laboratory plant. The permeate analysis showed 20% colour removal and 60% COD decrease. On the basis of these results, a semi-industrial system was built. With this plant, the permeate characterization showed similar results. The system was found to be scalable and suitable for the treatment of this kind of effluents.Finally, new dyeings were performed with both permeates. Monochromatic dyeings were carried out with 100% permeate whereas 50% permeate was reused for dyeings with a mixture of three dyes. The colour differences were found to be lower than 1.5, which was the acceptance value established.