Authors : Muqadas Mustafa; Muhammad Ismail; Muhammad Waqar Talib; Gao Xiaoya; Chen Xiaoguang

Volume/Issue : Volume 11 - 2026, Issue 4 - April

Google Scholar : https://tinyurl.com/5yzrvyrr

Scribd : https://tinyurl.com/56v27ysy

DOI : https://doi.org/10.38124/ijisrt/26apr108

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Abstract : This study evaluated the effectiveness of a spiral symmetry stream anaerobic bioreactor (SSSAB) treating bamboo degumming wastewater (BDW) under various hydraulic retention time (HRT) conditions. The reactor was operated across three phases with progressively decreasing HRTs of 20h, 14h, and 7h, while pH stability, ammonia nitrogen transformation, and COD removal efficiency were observed. The SSSAB performed effectively at HRT of 14 hours with COD removal efficiency of 75–80%, consistent effluent pH between 6.8 and 7.2, and active ammonification of organic nitrogen. The system demonstrated successful microbial acclimation at HRT of 20 hours, with COD elimination efficiency increasing from 50% to 75%. However, process instability developed when HRT was lowered to 7 hours, indicated by a dramatic drop in COD removal efficiency to 40%, effluent acidification to pH 5.2, and decreased ammonification activity because of inadequate contact time and possible biomass washout. These results provide crucial operational insights for the use of high-rate anaerobic bioreactors in the treatment of lignin-rich industrial wastewater. They demonstrate that although the SSSAB performs well under moderate hydraulic loading, there is a critical HRT threshold below which system failure occurs.

Keywords : Bamboo Degumming Wastewater; Hydraulic Retention Time; Spiral Symmetry Stream Anaerobic Bioreactor; Anaerobic Digestion; COD Removal; Ammonification.

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