Nutrient Removal From Swine Wastewater in a Combined Vertical and Horizontal Flow Constructed Wetland System

Abstract

This study aimed to assess the performance of a combined vertical flow (VFCW) and horizontal subsurface-flow (HFCW) constructed wetland systems built on a pilot scale and submitted to different configurations and organic load application rates of pre-treated swine wastewater (SWW) in anaerobic systems on the nitrogen and phosphorus removal.The average values of redox potential in the systems were between anoxic and aerobic conditions, favoring an increased nitrate concentration in VFCW. Nitrogen removal by VFCW-HFCW system can be considered as satisfactory, reaching removal values of 75%. VFCW and HFCW proved to be limited in phosphorus removal, reaching values of 48%.

A Combined System Using Lagoons and Constructed Wetlands for Swine Wastewater Treatment

“…Concerning the depuration performance of the constructed wetland, the reduction in the pH of SW, which was close to neutrality, was in accordance with Boas et al (2018) [54], who worked on CWs combining H-SSF and V-SSF systems, which favor the microbial activity of OM degradation and nutrient conversion.…”

“…Literature reports COD removal efficiencies in the range of 50-80% [33,35,36,60] with an extreme value of 99.5% detected by Masi et al (2017) [14] working in a CW combined system (as in our study). N removal varies between 60% and 80% according to many authors [3,8,11,27,36,54], but extreme values are also reported (10-40% [33,35] to 99% [14]). In our study, the TKN removal efficiency for the CW system with RR = 4:1 is in the range reported by the majority of studies, and it is not far from the optimal value of [14] in the CW with RR = 10:1.…”