Mathematical Model Development and 3D Printing of Cylindrically Shaped Biofilm Carrier Media from Recycled Plastic Waste for Wastewater Treatment

Selamo Basile Nyuysoni,Patrick G Home,James M Mutua

doi:10.4236/jep.2022.131002

Abstract

Wastewater management and purification remain one of the greatest problems of mankind. The biological wastewater treatment technique uses a biofilm media carrier where microorganisms attach themselves to the surface. This biofilter is usually made from virgin plastic pellets and can also be produced 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 centered 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 carrier 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 surface 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 results. The errors in SSA obtained from the model with respect to the SolidWorks 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 transforming plastics into biofilters, waste plastics are mopped up reducing pollutions. Consequently, the deployment of such biofilters will enhance efficient wastewater treatment for a cleaner environment and the wellbeing of human race.

Highlights

Pollution remains one of the world’s critical problems major sources of water contamination which leads to water pollution are oil pollution, atmospheric deposition, global warming, radioactive waste, underground storage leakage, industrial waste, marine dumping, sewage and wastewater [1]
This work is centered on the recycling of waste plastic to make filaments which are used for 3D printing of a high specific surface area (SSA) less clogging biofilm carrier through the parametric redesign
This study shows that analytical models can be developed for cylindrically shaped carriers

Summary

Introduction

Pollution remains one of the world’s critical problems major sources of water contamination which leads to water pollution are oil pollution, atmospheric deposition, global warming, radioactive waste, underground storage leakage, industrial waste, marine dumping, sewage and wastewater [1]. If appropriate and efficient methods are not used in mitigating these pollutions, it could result in illnesses, death of mankind, and other marine habitats. Mechanical, chemical, and biological methods are used in wastewater treatment. The biological technique is achieved by using biofilm media carriers produced from virgin plastic pellets. These pellets are extruded to make standard filaments for the 3D printing of biofilters. In the recycling of plastics, the plastic wastes are collected, processed, ground to make pellets [2]. There are generally seven categories of plastic generally recycled which include low-density polyethylene (LDPE), polyethylene terephthalate (PET), primarily polycarbonate (PC), high-density polyethylene (HDPE), polyvinyl chloride (PVC), polypropylene, and polystyrene (PS) [3] [4]

Methods

Results

Conclusion