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The development of treatment processes from laboratory scale to industries involves a lot of troubles due to the automation of process parameters and fluctuated characteristics of wastewater. In the present study, six different real-time textile effluents of samples such as S1 to S6 are characterized and treated by electrocoagulation process using Stainless Steel (SS) and Aluminum (Al) electrodes. The maximum removal efficiencies of color as 94%, turbidity as 99%, Chemical Oxygen Demand (COD) as 84% and Biological Oxygen Demand (BOD) as 82% is obtained for effluent sample S1 with fixed operational conditions such as the applied voltage of 4V, inter-electrode distance of 3 cm, the surface area of the electrode of 25 cm2 and agitation speed of 500 rpm respectively. After the electrocoagulation process, the BOD5/COD ratio of all effluent samples is observed as biodegradable limits. Under the fixed conditions, the operational cost for the treatment of effluent sample S1 analyzed as 2.42 and 1.01 $/m3 by using SS and Al electrodes respectively.

Accumulation of large quantity of non-biodegradable textile dyes into the environment made much attention to finding a suitable solution for the degradation of textile dyes. In this present study, decolorization efficiency of two different treatment technologies such as Photo-Assisted Chemical Oxidation (PACO – UV/H2O2) and Electrocoagulation (EC) on Reactive Blue 194 dye solution (RB194) at different operational conditions were analyzed and the competitiveness of the treatment technologies in terms of energy consumption and operational costs were discussed. Even though both the processes follow different mechanistic approach for the degradation of dye solution, both the processes achieved more than 99% of decolorization efficiency. In terms of material/chemical consumption for the decolorization of dye solution PACO (US$ 0.016) competes with the EC (US$ 0.5937). But in terms of electrical energy consumption as well as the overall operating cost EC process compete (US$ 0.0481 & US$ 0.6418) with the PACO process (US$ 1.0267 & US$ 1.04337).

The present study involves optimization of UV/H2O2process on a simulated dye bath effluent by varying initial H2O2concentration, pollution load, and pH. The process was optimized by four factors and three levels of Box–Behnken design coupled with response surface methodology. During the experiment, color removal and degradation studies were also performed to ensure the treatment efficiency. The results obtained show that the color removal efficiency can be achieved within a short time due to the degradation of the structure which is more susceptible to oxidation. Then slower and gradual degradation of the simple and conjugated aromatic compounds takes place. In the first 5 min of the irradiation of the dyes, the pH value decreased from 11 to 9.5 and for another pH value decreased from 9 to 7.01. The drop in the pH value is mainly due to the formation of organic as well as inorganic acid as a degradation product. Under the optimum operating conditions such as pollution load of 64%, initial concentration of H2O20.6 M, initial pH 8, and treatment time of 81 min the predicted removal efficiencies are 98.77 and 86.11% for Color removal and COD removal, respectively. [ABSTRACT FROM AUTHOR]