Modeling chlorophenols degradation in sequencing batch reactors with instantaneous feed-effect of 2,4-DCP presence on 4-CP degradation kinetics

Abstract

Two instantaneously fed sequencing batch reactors (SBRs), one receiving 4-chlorophenol (4-CP) (SBR4) only and one receiving mixture of 4-CP and 2,4-dichlorophenol (2,4-DCP) (SBRM), were operated with increasing chlorophenols concentrations in the feed. Complete degradation of chlorophenols and high-Chemical oxygen demand (COD) removal efficiencies were observed throughout the reactors operation. Only a fraction of biomass (competent biomass) was thought to be responsible for the degradation of chlorophenols due to required unique metabolic pathways. Haldane model developed based on competent biomass concentration fitted reasonably well to the experimental data at different feed chlorophenols concentrations. The presence of 2,4-DCP competitively inhibited 4-CP degradation and its degradation began only after complete removal of 2,4-DCP. Based on the experimental results, the 4-CP degrader's fraction in SBRM was estimated to be higher than that in SBR4 since 2,4-DCP degraders were also capable of degrading 4-CP due to similarity in the degradation pathways of both compounds.

Microbial Degradation of Dye-Containing Wastewater

“…Performance of the reactor also decreases with further increase in substrate concentration due to inhibition of microbial growth by substrate concentration itself as reported by Kargi and Eker (2005). The flocs reported by Sahinkaya and Dilek (2007) have a high degradation rate at low concentration, but at high concentration they were also inhibited leading to a decrease in the degradation rate.…”

Aerobic granulation for wastewater bioremediation: A review

“…The substrate degradation efficiency of aerobic granules increases with an increase in substrate concentration up to a certain limit, then decreases (performance of the reactor also decreases) with further increase in substrate concentration, due to inhibition of microbial growth by substrate concentration itself as claimed by Tay et al (2004b) and Khan et al (2011b). It was also reported that microbial flocs have a high degradation rate at low concentration, but at high concentrations they were also rapidly inhibited, leading to a similar decrease in degradation rate (Sahinkaya and Dilek, 2007).…”

Aerobic granular treatment of 2,4‐dichlorophenol

“…A very few authors have studied the degradation profile of chlorophenols. Sahinkaya and Dilek (2007) studied the removal rate of 4-chlorophenol (4-CP) and reported the specific degradation rate to be 3.34 mg 4-CP gVSS −1 h −1 (80 mg 4-CP gVSS −1 day −1 ). Wang et al (2000) studied the degradation profile of 2,4-DCP at different concentrations (50, 100, and 200 mg L −1 ) using Bacillus insolitus.…”