Faculty Publications
Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736
Publications by NITK Faculty
Browse
2 results
Search Results
Item Residence Time Distribution Studies in a Modified Rotating Packed Disc Contactor: Mathematical Modeling and Validation(De Gruyter Open Ltd, 2020) Kalnake, R.P.; Murthy, D.V.R.; Achar, A.; Raval, K.A modified rotating packed disc contactor (RPDC) with the maximum working volume of 65 liter is designed for biological waste water treatment. A hollow disc with radial vanes mounted on the disc was a modified design of this contactor. Stimulus-response experiments were conducted in the contactor to understand liquid mixing behavior under different operating conditions. The recycle stream was also used in the operation of the contactor. Experiments were conducted for different number of discs, rotational speeds and recycle ratios. The disc design and recycle ratio had marked influence on the mixing behavior. An increase in disc rotation and recycle ratio produced a well-mixed flow behavior. Moreover, the surface area available in the RPDC was about 4 times more than the surface area available in a standard rotating biological contactor (RBC) operating at similar conditions. A mathematical model was developed for the flow behavior under recycle and a good agreement was found between the model and experimental results. © 2020 Walter de Gruyter GmbH, Berlin/Boston 2020.Item Enhanced degradation of azo dye using mixed cultures of white-rot fungi in a modified rotating packed disc bioreactor and reuse of treated water(Elsevier Ltd, 2023) Kalnake, R.P.; Raval, R.; Murthy, D.V.R.; Vanzara, P.B.; Raval, K.Reactive azo dyes are toxic and carcinogenic. In this study, mixed cultures of white-rot fungi (WRF) are used to treat synthetic reactive black 5 (RB-5) wastewater in a modified rotating packed disc bioreactor (RPDB). The continuous degradation studies were carried out for 25 days under the influence of the recycle stream in which 3665 L of synthetic effluent was treated. The dye wastewater was completely decolorized with more than 93 % chemical oxygen demand (COD) reduction using the mixed fungal culture. During the continuous operation, the COD of influent reduced more than 85 % for successive 25 days of continuous operation at hydraulic retention time of 10.8 h. The dry biomass loading was about 0.14 g/g GAC at the end of the continuous process. The rate of COD removal followed first order kinetics with a rate constant of 0.026 per hour. The treated water was reused to produce melanin from microbial culture. © 2023 Elsevier Ltd