Journal of Environmental Protection, 2022, 13, 15-31 https://www.scirp.org/journal/jep ISSN Online: 2152-2219 ISSN Print: 2152-2197 DOI: 10.4236/jep.2022.131002 Jan. 12, 2022 15 Journal of Environmental Protection Mathematical Model Development and 3D Printing of Cylindrically Shaped Biofilm Carrier Media from Recycled Plastic Waste for Wastewater Treatment Selamo Basile Nyuysoni 1* , James M. Mutua 2 , Patrick G. Home 3 1 Department of Mechanical Engineering, Pan African University Institute for Basic Sciences, Technology and Innovation, Nairobi, Kenya 2 Department of Mechanical Engineering, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya 3 Department of Soil, Water and Environmental Engineering, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya Abstract Wastewater management and purification remain one of the greatest prob- lems of mankind. The biological wastewater treatment technique uses a bio- film media carrier where microorganisms attach themselves to the surface. This biofilter is usually made from virgin plastic pellets and can also be pro- duced from recycled waste plastic and used in wastewater treatment. The need to treat water using low-cost carrier media has led to finding alternative sources of materials for biofilter manufacturing. Therefore, this work is cen- tered on the recycling of waste plastic to make filaments which are then used for 3D printing of a high specific surface area (SSA) less clogging biofilm car- rier through the parametric redesign. In the current study, the polypropylene material was recycled to make a 2.85 mm diameter filament compatible with the Ultimaker S3. Moreover, analytical models and governing equations were developed for the design of the K3 Kaldnes and MB3 media. Empirical sur- face area (SA), specific surface area, and volume of the respective carriers were determined using the model developed. SolidWorks was used to design and evaluate the same parameters which were then compared to model re- sults. The errors in SSA obtained from the model with respect to the Solid- Works results for both the K3 Kaldnes and MB3 media were 0.34% and 0.76% respectively. With these small error margins, the model can serve as a tool and guideline for the designing of cylindrically shaped carriers. By transform- ing plastics into biofilters, waste plastics are mopped up reducing pollutions. How to cite this paper: Nyuysoni, S.B., Mutua, J.M. and Home, P.G. (2022) Mathe- matical Model Development and 3D Print- ing of Cylindrically Shaped Biofilm Carrier Media from Recycled Plastic Waste for Waste- water Treatment. Journal of Environmental Protection, 13, 15-31. https://doi.org/10.4236/jep.2022.131002 Received: November 18, 2021 Accepted: January 9, 2022 Published: January 12, 2022 Copyright © 2022 by author(s) and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access