Collective removal of phenol and ammonia in a moving bed biofilm reactor using modified bio-carriers: Process optimization and kinetic study

• Published in: Bioresource technology 2020-06, Vol.306, p.123177-123177, Article 123177
• Main Authors: Swain, Ganesh, Sonwani, R.K., Giri, B.S., Singh, R.S., Jaiswal, Ravi P., Rai, B.N.
• Format: Article
• Language: English
• Subjects: Central composite design; Grau kinetic model; Moving bed biofilm reactor; Polypropylene-polyurethane foam
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2020.123177

[Display omitted] •The process parameters such as pH, RT, and AFR were optimized using RSM.•92.6% of phenol was removed in MBBR filled with PP-PUF carriers.•The second-order kinetic model was appropriate for MBBR during pollutant removal. The performance of a moving bed biofilm reactor (MBBR) with bio-carriers made of polypropylene-polyurethane foam (PP-PUF) was evaluated for the collective removal of phenol and ammonia. Three independent variables, including pH (5.0–8.0), retention time (2.0–12.0 h), and airflow rate (0.8–3.5 L/min) were optimized using central composite design (CCD) of response surface methodology (RSM). The maximum removal of phenol and ammonia was obtained to be 92.6, and 91.8%, respectively, in addition to the removal of 72.3% in the chemical oxygen demand (COD) level at optimum conditions. First-order and second-order kinetic models were analyzed to evaluate the pollutants removal kinetics in a MBBR. Finally, a second-order model was found to be appropriate for predicting reaction kinetics. The values of second-order rate constants were obtained to be 2.35, 0.25, and 1.85 L2/gVSS gCOD h for phenol, COD, and ammonia removal, respectively.