Combined high-rate contact stabilization and chemically enhanced primary treatment for enhanced recovery of organic matter and biogas from sewage

• Published in: Bioresource technology Vol. 413; p. 131560
• Main Authors: Song, Minsu, Park, Jihye, Lee, Joonyeob, Bae, Hyokwan
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.12.2024
• Subjects: Carbon recovery rate; Chemically enhanced primary treatment; Energy-positive wastewater treatment; High-rate contact stabilization; Single-stage; Chemically enhanced primary treatment; Energy-positive wastewater treatment; Carbon recovery rate; High-rate contact stabilization; Single-stage
• ISSN: 0960-8524; 1873-2976; 1873-2976
• DOI: 10.1016/j.biortech.2024.131560

[Display omitted] •The serial HRCS-CEPT achieved a COD removal efficiency of 84.5%.•The serial CEPT-HRCS showed critical failure due to microbial washout.•The Single-CR exhibited the highest CRR of 0.780 g-CODCH4/g-CODinf.•The integration of HRCS and CEPT is highly effective in phosphorus removal.•Selective pressure in HRCS led to a microbial community with PHA storage capability. This study examined integrating high-rate contact stabilization (HRCS) and chemically enhanced primary treatment (CEPT) for wastewater to improve the carbon recovery rate (CRR). Enhancing chemical oxygen demand (COD) removal efficiency was hypothesized to improve the CRR. The evaluation covered serial HRCS-CEPT, serial CEPT-HRCS, and single-stage carbon recovery (Single-CR). The COD removal efficiencies for individual HRCS and CEPT were 50.3 % and 56.2 %, respectively. The serial CEPT-HRCS system failed in the HRCS process due to poor settling, resulting in microbial washout. However, the serial HRCS-CEPT system achieved the highest COD removal efficiency (84.5 %). The Single-CR system exhibited the highest CRR of 0.780 ± 0.083 g-CODCH4/g-CODinf, identifying it as the most promising process for energy-positive wastewater treatment. The selective pressure in the high-rate system resulted in a simplified and specialized bacterial community, mainly comprising microorganisms with high polyhydroxyalkanoate storage capacity, such as Lactococcus sp., Enterobacter sp., and Acinetobacter sp.