Removal, potential reaction pathways, and overall cost analysis of various pollution parameters and toxic odor compounds from the effluents of turkey processing plant using TiO2-assisted UV/O3 process

In the present study, removal of hazardous toxic odor compounds with color, COD and turbidity were concurrently investigated for the effluents of a turkey processing plant located in Bolu, Turkey. A hybrid TiO2 assisted photo-ozonation (UV/TiO2/O-3) process was set to address this issue. Subsequently, a comprehensive GC/MS method was developed for quantification of odor compounds. Finally, a complete overall cost analysis was incorporated with the findings of the study to demonstrate an economic analysis of the process. Descriptive results showed that the effluents had high pollution content in terms of color (0.374 IU; b = - 0.06), COD (146 mg/L O-2) and turbidity (15.52 NTU). Moreover, dimethyl silanediol (DS, 34.3%), acetic acid (AA, 20.5%), and diisobutyl phthalate (DP, 32.5%) were determined as major odor compounds of the effluents. After UV/TiO2/O-3 process, DS, AA, and DP were reduced to 12.4%, 12.0%, and 8.4%, respectively under the operating conditions of ozone dose of 16 mg/L, initial pH of 7.5, reaction time of 25 min, and catalyst dose of 3 g/L TiO2. At the same conditions removal efficiencies of color, COD and turbidity were obtained %99, %85, and 78%, respectively. These values demonstrated the accuracy of UV/TiO2/O-3 process in terms of removal of hazardous odor compounds and the other pollution parameters. Studies on reaction mechanism showed that main degradation mechanism occurred in three ways: formation of long-chained cyclic compounds from DS (1), formation of acetamide and ammonium acetate from AA (2), and formation of phthallic acid from DP (3). Finally, overall cost analysis showed that the current process costed 0.014 $ per 1 L of treated effluent and this value showed that the current process met the economic criteria in terms of feasibility.