Investigation of the potato chips processing wastewater treatment by hybrid constructed wetland systems

This study investigates the use of a hybrid constructed wetland system in the treatment of potato processing industry wastewater. The potato processing wastewater used in the study was supplied by BOLPAT İnc., located in Bolu, at certain periods between 06/08/2015 and 24/06/2016, and for the hybrid system, the plant, Cyperus alternifolius, was used. The hybrid system was arranged in a manner whereby the vertical reactors followed the horizontal reactors. In the hybrid system, two groups were formed, a plant group and a control group, in order to determine the treatment effect. The study was carried out in two sets, with KOİ, NH4-N, NO3-N, NO2-N, PO4-P, pH, ORP, EC, AKM and turbidity analyses being performed on the input wastewater and the output samples of the reactors in both sets. Soil/silt mixture, pumice stones and pebbles were used as filling materials in the vertical reactorsin Set-1, whereas only zeolite was used in the horizontal reactors. Unlike Set-1, in Set-2, the filling materials were modified in order to improve the treatment performance of the hybrid system. As part of this modification, zeolite, pumice stones and pebbleswere used in the vertical reactors and only zeolite in the horizontal reactors. Results from the analyzes performed on Set-1 showed 87% COD, 56% NH4-N and 57% PO4-P remediation values in the hybrid system with plant, while results from the analysis on showed 84% COD, 53% NH4-N and 52% PO4-P remediation values in the hybrid system with no plant. Results from the analyzes performed on Set-2 showed 87 % COD, 83 % NH4-N and 82 % PO4-P remediation values in the hybrid system with plant, while results from the analysis on showed 77% COD 77 % NH4-N and 73 % PO4-P remediation values in the hybrid system with no plant. According to the final results obtained at the end of the study, hybrid constructed wetland systems proved to be effective in removing ammonia and organic matter. Furthermore, it was found that in both sets the use of pumice stones, pebble stones and zeolite as filling material contributed to wastewater treatment in the constructed wetland systems. SEM imaging showed biofilm formations in both sets. In conducting MALDI TOF/ TOF MS analysis, the microorganisms in the biofilm structure and the role that they played in potato wastewater treatment were determined. The following growth modeling applications were carried out for the plants used in the study: proportional, linear, quadratic, quadratic/zero, parabola, cubic, exponential, restricted exponential, logistic, Von Bertalanffy, Gompertz and Richards. The cubic model was determined to be suitable for the horizontal and vertical reactors in the planted system of Set-1, while the logistic and Von Bertalanffy models were deemed suitable for the horizontal and vertical reactors, respectively, in the planted system of Set-2.