Enhancing treated wastewater effluent characteristics using hybrid biofilm/activated sludge process – a case study

Abstract

This paper documents the results of 12 months of monitoring of an upgraded hybrid moving bed biofilm reactor-conventional activated sludge wastewater treatment plant (MBBR-CAS WWTP). It also targets the assessment of the increment of the hydraulic load on existing treatment units with a zero construction and land cost. The influent flow to the plant was increased from 21,000 m3 d−1 to 30,000 m3 d−1, 40% of the existing CAS reactor volume was used for the MBBR zone with a carrier fill fraction of 47.62% and with Headworks Bio ActiveCell™ 515 used as media; no modifications were made for the primary and secondary tanks. The hybrid reactor showed high removal efficiencies for biochemical oxygen demand (BOD5), chemical oxygen demand (COD) and total suspended solids (TSS), with average effluent values recording 33.00 ± 8.87 mg L−1, 52.90 ± 9.65 mg L−1 and 29.50 ± 6.64 mg L−1 respectively. Nutrient removals in the hybrid modified biological reactor were moderate compared with carbon removal despite the high C/N ratio of 12.33. Findings in this study favor the application of MBBR in the upgrading of existing CAS plants with the plant BOD5 removal efficiency recording an increase of about 5% compared with the plant before upgrade and effluent values well within the legal requirements.

Reclaimed water application to vegetation restoration in mining area: Determination of water quality standards and optimization of moderate treatment technology

“…The traditional activated sludge and the microorganisms attached to the filler added form a biofilm system which can improve wastewater treatment performance in hybrid biological reactor [11][12][13]. The suitable fillers ratio is beneficial to improve the effluent quality.…”

Efficacy of Nitrogen and Phosphorus Removal and Microbial Characterization of Combined A2O-MBBR Constructed Wetlands

“…The anaerobic-oxic (A/O), anaerobic-anoxic-oxic (A 2 O), and oxidation ditch processes are mature domestic sewage treatment processes that occupy mainstream positions in municipal wastewater treatment plants, of which A 2 O is the most commonly used synchronous nitrogen-and phosphorus-removal process [4]. Moving bed biofilm reactor (MBBR) upgrading is a relatively inexpensive and efficient upgrade program for sustainably upgrading municipal sewage treatment plants, which saves land and construction costs and is suitable for upgrading small sewage treatment plants [5]. Embedding MBBR in the A 2 O process optimizes the distribution of carbon sources, increases the microbial structure's stability, improves the reactor's internal biomass, and effectively enhances the effectiveness of nitrogen removal and phosphorus removal [6].…”