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The optimization of ultrasonication process applied to linear alkyl benzene sulfonic acid (LABSA) degradation is investigated with response surface methodology in this study. Methylene blue active substance assay is used as a mean to monitor the degradation of LABSA. The effects of independent process variables (initial LABSA concentration, pH, and reaction time) on main material degradation are investigated. Among the independent variables, the greatest effect on LABSA degradation is observed for reaction time. Besides this, the effects of both reaction time and initial LABSA concentration are quite similar. The initial pH value of the solution has a lower effect on degradation performance when compared to other parameters. The predicted maximum detergent degradation was 75% at the optimal conditions of pH 7.8, initial LABSA concentration of 20 mg L−1, and reaction time of 70 min. Specific cost of LABSA degradation by ultrasonic treatment varies from 0.579 to 4.657 Euro g−1 removal LABSA. According to the results of sonication treatment applied to real wastewater, approximately 40% of the LABSA degradation is achieved at three pH values (5.27, 7.50, and 9.59). Because the original pH of the real wastewater is 9.59, it is more feasible to run experiments at this pH value.

In Turkey, the commercial laundry wastewater is usually discharged to the receiving water bodies and its reuse potential is ignored. This wastewater is grouped into the greywater due to their content of organic and inorganic pollutants. In recent years, the sequential processes have become more preferable in greywater treatment and reuse. In this study, a batch adsorption process was applied for further treatment of commercial laundry wastewater which is also pre-treated by means of the electrocoagulation process. In adsorption, two different composites of waste hazelnut shell derived activated carbons, which are supported with polyaniline (PAn/HS) and polypyrrole (PPy/HS), were used as adsorbents. The efficiency of the process was evaluated by means of an experimental design, and the response surface methodology was applied for this purpose. In the experiment with PAn/HS, the chemical oxygen demand (COD) 75% removal efficiency was accomplished with adsorbent dosage of 0.9 g, at pH 8, with 125 rpm mixing rate and for 77.5 min reaction time. For PPy/HS under the same experimental conditions, the COD removal efficiency was obtained as 20%. The utilization of waste hazelnut shell derived composites as adsorbents for commercial laundry wastewater treatment is a good alternative. The production costs of adsorbents were estimated as 0.70 USD/g and 3.21 USD/g for PAn/HS and PPy/HS, respectively. In terms of the production cost, the PAn/HS composite is approved more agreeable as adsorbents for commercial laundry wastewater treatment.

Effluents coming from potato chips manufacturing have high organic loads and require adequate treatment before discharge to environment. In this study, O 3 /UV/ H 2 O 2 advanced oxidation process was applied to treat these wastewaters. With this aim, batch experiments were conducted in a reaction tank equipped with ozone injection and UV irradiation. Process variables were determined to be pH, ozone concentration, reaction time, H 2 O 2 dosage and efficiency of the system was evaluated considering total organic carbon (TOC) removal. Central composite design technique was applied to examine the individual and synergetic effects of the experimental factors. A quadratic model was developed to maximize the TOC removal. Furthermore, operation costs were calculated for different experimental conditions and interactions between process variables and costs were analysed. 64 Water and Environment Journal 31 (2017) 64-71 V C 2016 CIWEM. Water and Environment Journal. Print ISSN 1747-6585 Fig. 4. The interactions between O 3 and time (a), O 3 -H 2 O 2 (b) and O 3 -pH (c) for TOC removal costs. [Colour figure can be viewed at wileyonlinelibrary.com] Treatability of food wastewater by AOPs and process optimization A. Arslan et al.