Wastewater quality evaluation in terms of wastewater quality index using hybrid constructed wetland for treatment of dairy and municipal wastewater

The world's most pressing problem is water shortage, which is made worse by fast industrialization and urbanization, especially in places like India where untreated effluent presents serious threats to human health and the environment. In order to treat dairy and municipal wastewater, this study assesses the efficacy of a two-stage hybrid constructed wetland (CW) system. The WWQI is the primary focus of this evaluation over a range of mixing ratios. Before and after treatment, many physicochemical parameters were examined, including pH, total suspended solids (TSS), chemical oxygen demand (COD), biochemical oxygen demand (BOD), total phosphorus (TP), ammonia nitrogen ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:mrow><mml:msub><mml:mi>NH</mml:mi> <mml:mn>3</mml:mn></mml:msub> <mml:mo>-</mml:mo> <mml:mi>N</mml:mi></mml:mrow> <mml:annotation>$$ {NH}_3-N $$</mml:annotation></mml:semantics> </mml:math> ), and nitrate nitrogen ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:mrow><mml:msub><mml:mi>NO</mml:mi> <mml:mn>3</mml:mn></mml:msub> <mml:mo>-</mml:mo> <mml:mi>N</mml:mi></mml:mrow> <mml:annotation>$$ {NO}_3-N $$</mml:annotation></mml:semantics> </mml:math> ). The hybrid CWs system dramatically lowers pollutant concentrations, according to the results, with combinations containing higher amounts of MWW showing the best results. The WWQI values, which change from "unfit for any uses" in untreated DWW to "excellent" quality in treated MWW, show these advancements. The results highlight the potential of hybrid CWs as an effective and sustainable wastewater treatment method, especially when it comes to maximizing the proportion of dairy to municipal wastewater. This study adds to our knowledge of efficient wastewater treatment techniques and highlights the significance of incorporating eco-friendly technologies to tackle water scarcity issues. PRACTITIONER POINTS: Hybrid Constructed Wetlands (HCWs) are effective in removing TSS, BOD, COD, TP, ammonia nitrogen, and nitrate nitrogen from dairy and municipal wastewater. On the basis of HCWs performance determine the Wastewater Quality Index (WWQI) for four different ratio proportions of dairy and municipal wastewater. This index is more useful for water quality status determination and treated water reuse for various purposes. This also benefits sustainable treatment technology and contributes to achieving SDGs.