Textile Wastewater

Following new trends we applied oxygen uptake rate (OUR) tests as well as long-term tests (in two batch bioreactors systems) in order to assess the biodegradability of textile wastewater. Effluents coming from a dyeing factory were divided into two streams which differed in inorganic and organic contaminants loads. Usefulness of the stream division was proved. Biodegradation of the low-loaded stream led to over 97% reduction of biochemical oxygen demand (BOD 5) together with 80% reduction of chemical oxygen demand (COD) and total organic carbon (TOC). Most of the controlled parameter values were below the levels allowed by legislation for influents to surface water, whereas the high-loaded stream was so contaminated with recalcitrant organic compounds that despite the reduction of BOD 5 by over 95%, COD, TOC, total nitrogen and total phosphorus levels exceeded permissible values. OUR tests were aimed at determination of the following kinetic parameters: maximum specific growth rate (μ Max), half-saturation constant, hydrolysis constant and decay coefficient for activated sludge biomass for both types of textile wastewater studied. The values of kinetic parameters will be applied in activated sludge models used for prediction and optimisation of biological treatment of textile wastewater.

To develop the waste water solutions challenging task. To design sustainable wastewater solution requires information about new ideas, new systems and latest technology. Generally it is assumed that, decision making needs to involve field experts and engineers to define values and brainstorms solution. This paper describes a decision support system model that is designed to help community planners to identify the solution which balance the environmental, economic and social needs. System will be scalable, adaptable and flexible. Our decision support system will take modular description of components and description of community constraints, suggest the design of alternative waste water system, and facilitates evaluating how well each design satisfies the given constraints. Decision support system will give alternatives with visualization of the effect of various trade-offs and their effect in the relation of the community's goals. I. INTRODUCTION It is notable that, after industrial revolution, population growth and urbanization there is intense need of wastewater management system. As a research, the past few years have been seen significant growth in innovation based on the idea of waste as resource rather than a non-usable material, with a focus on water energy and nutrients. The challenge of providing good management of domestic and industrial sewage is becoming very urgent as the majority of sewage infrastructure in the industrialized area will require changes and replacement in the near future and more than half of the people living in the large cities in the developing world lack access to proper sanitation services. Growing cost in combination with environmental concerns and the challenges involved in securing the quality and quantity of water heighten the urgency of the issue It has been repeatedly observed that successful implementation of scalable management solutions is strongly tied with environmental ,social, economic and political issues at different level and thus requires active engagement of verity of experts in addition to wastewater engineers identifying the most stable solution involves finding solution that minimize negative effects, while maximizing benefits for local and global environments.

The simultaneous use of Fenton reagent and irradiation for the treatment of textile wastewaters generated during a hydrogen peroxide bleaching process is investigated. The experimental conditions tested during this study provide the simultaneous occurrence of Fenton, Fenton-like and photo-Fenton reactions. The batch experimental results are assessed in terms of total organic carbon reduction. Identification of some of the chemical constituents of the effluent was performed by means of GC-MS. Other pollution related features of the initial effluent-like COD and color were also measured. The main parameters that govern the complex reactive system, i.e., light intensity, temperature, pH, Fe(II) and H2O2 initial concentrations have been studied. Concentrations of Fe(II) between 0 and 400 ppm, and H2O2 between 0 and 10,000 ppm were used. Temperatures above 25 degrees C and up to 70 degrees C show a beneficial effect on organic load reduction. A set of experiments was conducted under diff...

— Due to the reduction of groundwater resources, the artificial recharge of these resources through the reuse of treated wastewater (modified water) is an efficient way to tackle the problem. Some of the most important goals to be achieved regarding such a situation are the development of underground resources, building barriers to help avoid the penetration of the saline water to the underground water table in the coastal areas, creating additional levels of water treatment by soil and controlling the soil settlement. The modified water helps to compensate for the underground water. Asthe additional stage of the purification of the modified water offers assurance on the sewage management system, this natural water treatment created underground eliminates the need for costly wastewater treatment processes. Moreover, the groundwater aquifers provide a natural mechanism for the subsurface transfer of the modified water and eliminate the need for the surface storage facilities and associated problems, such as evaporatio n and the growth of algae, which degrade the water quality. One of the most commonly used methods is the aquifer storage and recovery (ASR) technology, which helps overcome the seasonal imbalance associated with the retrieval systems in the world. In the present paper, the methods used to realize this solution, including among others flood spreading, the soil aquifer treatment (SAT) systems, injection in unsaturated areas, and direct injection are examined. Furthermore, the advantages and disadvantages of using the modified water and the required hydraulic analyzes for designing direct injection wells and injection in unsaturated areas will also be investigated.

Membrane bioreactor (MBR) is a reliable and promising technology for wastewater treatment and reclamation applications. In spite of more than a decade of significant advances in developing fouling mitigation methods, different physical and cleaning protocols are still necessary to be developed to limit the membrane fouling. The use of scouring agents in MBR applications has been paid attention as a new approach as an energy-efficient way to control membrane fouling. Recently, mechanical cleaning by scouring agents is becoming as intense research area considering high efficiency of fouling reduction while requiring low energy consumption. In this review, fundamental and comprehensive assessments of the mechanical cleaning concepts and their applications with porous and nonporous scouring agents for MBR system are critically reviewed. The existing challenges and future research prospects on the mechanical cleaning technology associated with scouring agents for the MBR applications are also discussed.

Fenton Process, a type of Advanced Oxidation Processes is an efficient method for treating textile
wastewaters. However, excessive use of hydrogen peroxide and catalyst has made this process
economically non-feasible. Besides, industrial grade hydrogen peroxide costs $390 e500 per ton. One of
the means to overcome this problem is the in-situ production of hydrogen peroxide. In this paper, a
detailed review was conducted on the generation methods, degradation potential and optimum operating parameters for in-situ production of hydrogen peroxide/hydroxyl radicals. Additionally the scavenging aspect for hydroxyl radicals was also investigated. From this review, it can be concluded that
hydroxyl radical is highly oxidative and non selective in nature and its in-situ production can be performed through application of catalyst, ozonation, photocatalysis, electro and microbial fuel cells.
Furthermore, optimization of operating parameters can result in an increase in the yield of hydroxyl
radicals/hydrogen peroxide. Sonolysis as an auxiliary tool has potential to induce synergetic effects in
combination with Advanced Oxidation Processes to increase in-situ hydrogen peroxide production.
However, the problem of the scavenging effect is an aspect that needs to be dealt with, as hydroxyl
radicals are prone to deactivation by scavengers. Therefore based on the review, it is concluded that insitu production of hydrogen peroxide/hydroxyl radical for treating textile wastewater is economically
viable and practically feasible if careful selection of process is conducted through selective research

Membrane Bioreactor (MBR) is used besides municipal wastewater treatment in many industrial scale plants, such as textile sector. It can be operated under normal conditions on a by-pass system, or submerged in the reactor’s vessel, where it works in-line and operates by means of vacuum suction at low trans-membrane pressure. In wastewater treatment, MBR’s have significant advantages in regard to conventional activated sludge configuration due to the conditions and quality of the treated water. This work gives basic operation principle of MBR technology for textile wastewater treatment which is very important technology in nowadays environmental protection as well as analyses some advantages and disadvantages of the MBR process compared to the conventional activated sludge process. Membrane fouling and cleaning processes in MBR are also discussed.

The objective of the study was to evaluate the phytoremediation potential of three aquatic macrophytes (Commelina cyanea, Phragmites australis and Water Hyacinth (Eichhornia crassipes)) for treatment of municipal wastewater collected from Federal University of Technology, Akure (Nigeria). Laboratory scale of three constructed wetlands of dimensions 0.43 m x 0.93 m x 0.36 m in width, length and depth respectively, were developed to mimic natural conditions and was operated for a single experimental run with each macrophte at different retention time of 6, 9 and 12 days. These aquatic macrophytes were planted in separate ponds. Domestic wastewater from undergraduate students' hostel was introduced to the ponds. The raw wastewater sample and treated wastewater samples were analysed using standard laboratory methods for physical (Turbidity and Dissolved solids), chemical (pH, Nitrate, Nitrite, Phosphate, Sulphate Chemical Oxygen Demand and Biochemical Oxygen Demand) and bacteriological (Coliform bacteria) parameters. Results showed substantial diminutions in all parameters treated with the phytoremediators during the course of the study. Asides the three plants effectively removing Nitrate, Nitrite, phosphate and Sulphate pollutants, Phragmites australis gave the highest removal efciency for Phosphate (85.8%), Water hyacinth gave the highest removal efciency for pH (11.5%), Biochemical Oxygen Demand and Coliform bacteria and Commelina cyanea gave the highest removal efciency for turbidity (96.9%) and dissolved solids (82.9%) parameters of the domestic wastewater samples. The overall results of the phytoremediation studies indicate that the purication effectiveness of the three aquatic macrophytes were spontaneous, feasible and remarkable.

AND MAJID MUNEER Department of Chemistry, University of Agriculture, Faisalabad–38040, Pakistan †Environmental Protection Agency, Faisalabad, Pakistan 1Corresponding author's e-mail: hnbhatti2005@yahoo.com ... The present study was carried out to ...

Synthesis of Ag3PO4 photocatalyst under the varied concentrations of AgNO3 and Na2HPO4·12H2O as starting material has been successfully synthesized using the co-precipitation method. The concentration of AgNO3 is 0.1, 0.5, 1.0, and 2.0 M, whereas Na2HPO4·12H2O is 0.03, 0.17, 0.33, and 0.67 M, respectively. The co-precipitations were carried out under aqueous solution. As-synthesized photocatalysts were examined to degrade Rhodamine B (RhB) under blue light irradiation. The results showed that varying concentrations of starting materials affect the photocatalytic activities, the intensity ratio of [110]/[200] facet plane, and their bandgap energies of Ag3PO4 photocatalyst. The highest photocatalytic activity of the sample was obtained by synthesized using the 1.0 M of AgNO3 and 0.33 M of Na2HPO4·12H2O (AP-1.0). This is due to the high [110] facet plane and increased absorption along the visible region of AP-1.0 photocatalyst. Therefore, this result could be a consideration for the improvement of Ag3PO4 photocatalyst.

Water scarcity and pollution rank equal to climate change as the most urgent environmental turmoil for the 21st century. To date, the percolation of textile effluents into the waterways and aquifer systems, remain an intricate conundrum abroad the nations. With the renaissance of activated carbon, there has been a steadily growing interest in the research field. Recently, the adoption of titanium dioxide, a prestigious advanced photo-catalyst which formulates the new growing branch of activated carbon composites for enhancement of adsorption rate and discoloration capacity, has attracted stern consideration and supports worldwide. Confirming the assertion, this paper presents a state of art review of titanium dioxide/activated carbon composites technology, its fundamental background studies, and environmental implications. Moreover, its major challenges together with the future expectation are summarized and discussed. Conclusively, the expanding of activated carbons composites material represents a potentially viable and powerful tool, leading to the plausible improvement of environmental conservation.