Investigation of dye removal, bioelectricity production, and storage potentials in hybrid constructed wetland ecosystems

In his doctoral thesis research, it was determined that the mesocosm scale hybrid constructed wetland ecosystems (HEMs) with different configurations, under different hydraulic retention times (3, 4, and 5 days), were used for the removal of synthetic textile wastewater containing acid orange 7 (AT) dye as an azo dye. In this study, bioelectricity production and storability potentials were investigated in a timely manner. For the study, a mesocosm scale constructed wetland ecosystem, consisting of four different configurations horizontal-horizontal, horizontal-vertical, vertical-horizontal, and vertical-vertical, was established under natural field conditions. In hybrid ecosystems, zeolite-based filtration media was used as a filling material and Typha latifolia L. was used as a plant. As a result of bioremediation and bioelectricity production and potential storage experiments carried out on HEMs for 92 days determined that the ecosystem with a horizontal-horizontal configuration (HEM 1) has higher treatment and bioelectricity production and storability efficiency compared to other ecosystems. The average AT7, chemical oxygen demand, nitrate, ammonium, and total phosphorus removal of HEM1 were determined as 98.94%, 96.65%, 98.65%, 95.07%, and 98.27%, respectively. It was determined that HEM 1 produced an average of 0.799 V bioelectricity over 1000 Ω external resistance and the storage process (1.2 volt 600 mAH AAA battery) at the end of the 92-day experiment period took 225 minutes. The results show that the diversity of hybrid ecosystem configurations provides high efficiency for bioelectricity production with treatment efficiency. In addition, it was determined that the microbial factors responsible for the biodegradation of organic compounds and catalyzing the electron flow from the anode to the cathode were at the maximum level in the horizontal-horizontal configuration. As a result, it is recommended to choose an ecosystem with a horizontal-horizontal configuration in order to maximize the treatment efficiency, bioelectricity production, and storage potential in studies aimed at dye removal and bioelectricity production storage.