Textile Wastewater Treatment in a Spinning Disc Reactor: Improved Performances—Experimental, Modeling and SVM Optimization

The paper presents an experimental study regarding the treatment of a real textile wastewater using the spinning disc (SD) technology, either individually or associated with an advanced Fenton oxidation step. The SD efficiency was investigated by studying the color, suspended solids, or turbidity removals, at distinctive feeding flowrates (10–30 L/h) and disc rotating speeds (100–1500 rpm). The data revealed increasing removal trends and allowed to establish the highest removal values. Based on obtained experimental results, the wastewater treatment efficiency by SD technology was reasonably good and thus, the WW indicators can be improved within relatively short periods of time. Additionally, based on supervised learning algorithms, the study includes treatment modeling for turbidity and color removal, followed by turbidity removal optimization relying on the best learned models. Satisfactory results obtained with the modeling and optimization procedures provide useful predictions for the approached treatment processes. Furthermore, within this study, a Fenton oxidation process was applied to SD technology to minimize the color and solids content. The influence of pH, hydrogen peroxide and ferrous ions concentrations was also investigated in order to establish the highest removal efficiencies. Overall, the SD technology applied in textile effluents treatment proved to be an appropriate and efficient alternative to classical mechanical step applied within the primary treatment step and, when associated with an advanced oxidative process in the secondary step, rendered good improvement, namely of 62.84% and 69.46% for color and respectively, suspended solids removal.

Treatment of ultrahigh chemical oxygen demand chemical wastewater by Fenton oxidation

The article focuses on the Fenton oxidation process for the treatment of ultrahigh COD chemical wastewater from chemical plants. Optimum pH was determined as 2.0 and 10.0 for the first (oxidation) and second stage (coagulation) of the Fenton process, respectively. 0.465gFeSO4·7H2O, H2O2(30%)2ml, the mole tatio of H2O2 : Fe2+=10:1, adjust the pH of the solution to 10, after 1.5 hours of agitation, then add 5% PAM2ml to the solution, filtrate, extract, filtrate the clear liquid and dilute it three times, take 200ml of the diluted liquid, and add 0.465gFeSO4·7H2O, H2O2(30%)2ml, the mole tatio of H2O2 : Fe2+=10:1, adjust the pH of the solution to 10, after 1.5 hours of agitation, then add 5% PAM2ml to the solution, static stratification. For chemical wastewater, when the molar ratio H2O2/Fe2+ is 10:1, the removal rate of COD is the highest, provided 86.21–86.45% COD removal.

Advanced Oxidation of Segregated Streams for Effective Color Removal from Denim Processing Effluents

The study introduced footprint analysis as a new methodology and focused on differentiating wastewater streams with the highest color content and optimizing the advanced oxidation process for the segregated streams for effective color removal from denim processing. Experiments were implemented to four segregated streams rather than the entire plant effluent. A flow proportional composite mixture of segregated streams was used for color removal experiments using the advanced oxidation process with ozone and hydrogen peroxide and Fenton oxidation as other alternatives. The latter yielded the best results achieving total removal of color below visual detection limit after an optimum reaction time of 10 minutes. The Fenton oxidation process was also applied to a representative sample from the plant effluent after the physical-chemical treatment sequence, where color absorbance levels were lowered at all wavelengths below 1.0 m-1. The merit of the new footprint approach was confirmed by the results, which provided a conclusive indication that color treatment at source, implemented on selected segregated wastewater streams, presented concrete advantages over the end of pipe treatment of the overall effluent.

Removal of Tetracycline Antibiotic from Wastewater by Fenton Oxidation Process

This study aimed to remove the antibiotic tetracycline from a sample of synthetic wastewater using an advanced oxidation process by Fenton's reagent treatment. Central Composite Design (CCD) software was used to reduce the number of tests required to remove tetracycline. The independent variables identified in batch oxidation experiments are the concentrations of tetracycline (40–250 mg / L), hydrogen peroxide (20–600 mg / L), and Fe(II) (0–60 mg / L). The rate of tetracycline degradation was significantly influenced by the concentration of hydrogen peroxide and tetracycline. The reaction time required for tetracycline removal was determined to be 15 minutes. The optimal ratio of independent variants leading to complete degradation 100% of tetracycline was hydrogen peroxide / Fe2 + / tetracycline 310/30/145 mg / l.

A comparative study on removal of the dye wastewaters by nascent state manganese dioxide and ferric hydroxide under acid condition

Nascent state manganese dioxide (NSMD) or ferric hydroxide (NSFH) is the main intermediate during potassium permanganate or Fenton oxidation process, respectively, which plays an important role on the removal of...

Kinetic Study of Degradation of Basic Turquise Blue X-GB and Basic Blue X-GRRL using Advanced Oxidation Process

This study focuses on application of advanced oxidation (Photo-Fenton) processes to decolorize Basic Turquise Blue (BTB) X-GB 250% and Basic Blue (BB) X-GRRL 250% dyes. The percent decolorization was studied in terms of effect of variation in intensity of UV light at optimum conditions of all the parameters (pH = 3.0, H2O2 = 4.8 mM, FeSO4 = 1.6 mM, temperature = 50 °C, time = 80 min for BTB X-GB, and pH = 5.0, H2O2 = 5.6 mM, FeSO4 = 2.0 mM, temperature = 40 °C, time = 60 min for BB X-GRRL). Maximum decolorization was obtained at maximum intensity (15660 counts/min) of UV light as 96.17% for BTB X-GB and 88.48% for BB X-GRRL. First order, 2nd order and BMG kinetic models were used to analyze the data obtained for intensity of UV light. BMG model gives us the higher values of correlation coefficients for all data of both the dyes. The results have shown that Photo-Fenton oxidation process is the beneficial and effective for oxidation treatment of waste water effluents containing dyes as main pollutants.