Hybrid Constructed Wetland System Treating Swine Farm Wastewater Under Varying Hydraulic Loading Rates

Abstract

Swine farm wastewater contains high concentrations of organic matter, suspended solids, nutrients, and pathogenic microorganisms, posing significant environmental risks when discharged without effective treatment. The present study investigates the performance of a hybrid constructed wetland system for treating swine farm wastewater under varying hydraulic loading rates. The research focuses on evaluating pollutant removal efficiency, hydraulic performance, nutrient reduction, and operational stability associated with integrated wetland treatment configurations. Experimental analysis was conducted to examine the influence of hydraulic loading rate, retention time, substrate composition, vegetation type, and seasonal operating conditions on the removal of chemical oxygen demand, biochemical oxygen demand, total suspended solids, nitrogen, and phosphorus compounds. Results demonstrate that the hybrid constructed wetland system effectively combines physical filtration, microbial degradation, plant uptake, and adsorption mechanisms to achieve substantial wastewater purification and nutrient removal. The study further reveals that optimized hydraulic loading conditions significantly enhance treatment efficiency and improve oxygen transfer and microbial activity within the wetland media. Excessive hydraulic loading rates were found to reduce pollutant removal performance due to shortened retention time and hydraulic overloading effects. Comparative assessment with conventional wastewater treatment systems confirms the advantages of hybrid constructed wetlands, including lower energy requirements, reduced operational costs, and improved environmental sustainability for agricultural wastewater management. In addition, the integrated wetland configuration demonstrated enhanced resilience to fluctuations in wastewater composition and loading conditions.