3D printing and injection moulding of plastic packaging : an environmental and financial comparative assessment

Abstract

Over the past few years, manufacturing companies have become more environmentally conscious and are exploring alternative processes which reduce their environmental burden. 3D printing has been introduced as a potential alternative to conventional manufacturing processes to produce products which reduce the negative impacts on the environment. The aim of this dissertation was to analyse the environmental and economic feasibility of using 3D printing instead of injection moulding (IM) to produce cosmetic plastic packaging. The 3D printing technology used for this analysis was fused deposition modelling (FDM). To assess and compare the environmental impacts caused by using IM and FDM to produce the compacts, a life cycle assessment (LCA) exercise was carried out. The impacts of raw material production and manufacturing processes were assessed for both technologies to produce eighteen million compacts over twelve years. Results obtained showed that using FDM created a larger environmental impact when compared to using IM. Electricity consumption during printing was the greatest contributor, accounting for more than 80% of the total impact. This led to the conclusion that using FDM created an environmental burden which is five times greater than the impact of using IM to produce the cosmetic plastic packaging. In addition, through a life cycle costing (LCC) exercise, the economic feasibility of implementing FDM instead of IM to manufacture the compact was analysed. Using costing models, the cost per compact when manufactured using IM and FDM were found to be € 0.09 and € 1.58, respectively. The largest contributor to the FDM cost per compact was the material costs, which is much more expensive than that used for IM. Moreover, a net present value (NPV) model was used to understand the costs incurred over twelve years of compact production. The total NPV using FDM resulted to be 17 times greater than the total NPV when using IM. This further led to the conclusion that FDM is not a financially viable alternative compared to using IM to manufacture the compacts. Finally, quality testing was also carried out, where the injection moulded compacts resulted to be of superior visual and functional quality compared to the FDM printed compacts. In summary, this dissertation concluded that currently 3D printing is not a feasible alternative for IM to mass produce the compacts.