SCI和EI收录∣中国化工学会会刊

中国化学工程学报 ›› 2021, Vol. 29 ›› Issue (1): 391-400.DOI: 10.1016/j.cjche.2020.04.008

• Resources and Environmental Technology • 上一篇    下一篇

Application of an immobilized microbial consortium for the treatment of pharmaceutical wastewater: Batch-wise and continuous studies

Shabnam Murshid, Gnana Prakash Dhakshinamoorthy   

  1. Department of Chemical Engineering, SSN College of Engineering, Kalavakkam, Tamil Nadu 603110, India
  • 收稿日期:2019-11-22 修回日期:2020-03-01 出版日期:2021-01-28 发布日期:2021-04-02
  • 通讯作者: Gnana Prakash Dhakshinamoorthy
  • 基金资助:
    The authors wish to express their gratitude for the support extended by SSN College of Engineering, Chennai, Tamil Nadu, India.

Application of an immobilized microbial consortium for the treatment of pharmaceutical wastewater: Batch-wise and continuous studies

Shabnam Murshid, Gnana Prakash Dhakshinamoorthy   

  1. Department of Chemical Engineering, SSN College of Engineering, Kalavakkam, Tamil Nadu 603110, India
  • Received:2019-11-22 Revised:2020-03-01 Online:2021-01-28 Published:2021-04-02
  • Contact: Gnana Prakash Dhakshinamoorthy
  • Supported by:
    The authors wish to express their gratitude for the support extended by SSN College of Engineering, Chennai, Tamil Nadu, India.

摘要: In the present investigation, a microbial consortium consisting of four bacterial strains was selected for the treatment of pharmaceutical industry wastewater. The consortium was immobilized on a natural support matrix-Luffa and used for the treatment of real-time pharmaceutical wastewater in batch and continuous processes. The batch process was carried out to optimize the culture conditions and monitor the enzymatic activity. An array of enzymes such as alcohol dehydrogenase, aldehyde dehydrogenase, monooxygenase, catechol 2,3-dioxygenase and hydroquinol 1,2-dioxygenase were produced by the consortium. The kinetics of the degradation in the batch process was analyzed and it was noted to be a first-order reaction. For the continuous study, an aerobic fixed-film bioreactor (AFFBR) was utilized for a period of 61 days with variable hydraulic retention time (HRT) and organic loading rate (OLR). The immobilized microbes treated the wastewater by reducing the COD, phenolic contaminants and suspended solids. The OLR ranged between (0.56 ± 0.05) kg COD·m-3 d-1 to 3.35 kg COD·m-3·d-1 and the system achieved an average reduction of 96.8% of COD, 92.6% of phenolic compounds and 95.2% of suspended solids. Kinetics of the continuous process was interpreted by three different models, where the modified Stover Kincannon model and the Grau second-order model proved to be best fit for the degradation reaction with the constant for saturation value, KL being 95.12 g·L-1·d-1, the constant for maximum utilization of the substrate Umax being 90.01 g·L-1 d-1 and substrate removal constant KY was 1.074 d-1 for both the models. GC-MS analysis confirmed that most of the organic contaminants were degraded into innocuous metabolites.

关键词: Pharmaceutical wastewater, Microbial consortium, Immobilization, Batch study, Fixed film bioreactor, Kinetic studies

Abstract: In the present investigation, a microbial consortium consisting of four bacterial strains was selected for the treatment of pharmaceutical industry wastewater. The consortium was immobilized on a natural support matrix-Luffa and used for the treatment of real-time pharmaceutical wastewater in batch and continuous processes. The batch process was carried out to optimize the culture conditions and monitor the enzymatic activity. An array of enzymes such as alcohol dehydrogenase, aldehyde dehydrogenase, monooxygenase, catechol 2,3-dioxygenase and hydroquinol 1,2-dioxygenase were produced by the consortium. The kinetics of the degradation in the batch process was analyzed and it was noted to be a first-order reaction. For the continuous study, an aerobic fixed-film bioreactor (AFFBR) was utilized for a period of 61 days with variable hydraulic retention time (HRT) and organic loading rate (OLR). The immobilized microbes treated the wastewater by reducing the COD, phenolic contaminants and suspended solids. The OLR ranged between (0.56 ± 0.05) kg COD·m-3 d-1 to 3.35 kg COD·m-3·d-1 and the system achieved an average reduction of 96.8% of COD, 92.6% of phenolic compounds and 95.2% of suspended solids. Kinetics of the continuous process was interpreted by three different models, where the modified Stover Kincannon model and the Grau second-order model proved to be best fit for the degradation reaction with the constant for saturation value, KL being 95.12 g·L-1·d-1, the constant for maximum utilization of the substrate Umax being 90.01 g·L-1 d-1 and substrate removal constant KY was 1.074 d-1 for both the models. GC-MS analysis confirmed that most of the organic contaminants were degraded into innocuous metabolites.

Key words: Pharmaceutical wastewater, Microbial consortium, Immobilization, Batch study, Fixed film bioreactor, Kinetic studies