Six Sigma Production Implementation of PET-Modified HMA – A Latin American Case Study

ABSTRACT The increase in consumption of goods and products, mainly of disposable products, at the global level has resulted in a considerable impact to the environment. Specifically, waste plastics can be associated with an extremely high social cost and can greatly affect the local environment when not properly discarded. The United Nations Environment Programme estimates that 6.4 million tons of garbage end up in the oceans at an alarming rate of 200 kg per second. Plastics represent 80 % of these wastes. This paper proposes the use of waste plastics in the production of hot mix asphalt (HMA) based on a process production implementation using the identify, define, optimize, and validate Six Sigma methodology for quality control assurance. The procedure involved consumer use requirements, material analysis, HMA design, production design, quality control processes, and, finally, the construction of test sections in two different countries in Latin America: Costa Rica and Bolivia. One of the challenges documented in the paper was the implementation of the waste material-modified HMA on small, local producer facilities while meeting all production requirements to ensure the success of the process. Also, based on circularity principles, the project represents a revolution regarding the implementation of a linear production system within a circular process that is partly intended to ensure that the footprint of waste plastics on the environment is reduced while taking advantage of the properties of the waste polymers to improve the performance of the modified HMA.