A Kinetic Study on Chronic Response of Activated Sludge to Diclofenac by Respirometry

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CİVELEK YÖRÜKLÜ H., Topuz E., Aydin E., Çokgör E., Zengin Balcı G. E.

Water (Switzerland), cilt.16, sa.20, 2024 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 16 Sayı: 20
  • Basım Tarihi: 2024
  • Doi Numarası: 10.3390/w16202898
  • Dergi Adı: Water (Switzerland)
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Agricultural & Environmental Science Database, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), CAB Abstracts, Compendex, Environment Index, Food Science & Technology Abstracts, Geobase, INSPEC, Pollution Abstracts, Veterinary Science Database, Directory of Open Access Journals
  • Anahtar Kelimeler: biodegradation, emerging contaminant, non-steroidal anti-inflammatory drugs, respirometric modelling, sludge retention time
  • Yıldız Teknik Üniversitesi Adresli: Evet

Özet

The present study investigated the chronic response of activated sludge to the emerging pollutant diclofenac as well as its aerobic biodegradation potential at different sludge retention times (SRTs). The impact of prolonged exposure to diclofenac on microbial process kinetics was explored with respirometric modelling. The long-term operation of lab-scale reactors revealed that continuous feeding of diclofenac at relevant concentrations observed in municipal wastewaters did not affect carbon removal efficiency independentl of SRT. However, in case of diclofenac removal, 34% efficiency could be achieved at a higher SRT of 20 days. Kinetic evaluation showed that the increment in diclofenac dosing resulted in no adverse effect on the microbial growth rate except that high concentrations of diclofenac exposure decreased the growth rate at SRT of 10 days. A significant increase in hydrolysis rate was determined in the diclofenac-acclimated biomass for both SRTs; even at high concentrations of diclofenac exposure, the hydrolysis rate remained unchanged. Long-term acclimation to diclofenac had a progressive impact on the hydrolysis kinetics, which could be attributed to an alteration in the microbial culture profile. Overall, the results suggest that the operation with diclofenac-acclimated biomass at higher SRTs could enrich a microbial culture capable of overcoming the adverse effect of the pollutant and improve the biodegradation potential as well.