The Council for Scientific and Industrial Research (CSIR), in collaboration with the Department of Science and Innovation (DSI), is working on a demonstration project to evaluate the feasibility of using waste plastic in local road construction.
The project aims to identify different low-value plastic waste types – meaning waste plastics that are not currently attractive to the South African recycling sector – and evaluate their use as a binder/bitumen modifier in asphalt road surfacing.
Georges Mturi, senior researcher and manager of CSIR’s Advanced Material Testing Laboratories, says the idea is to support industry and government in finding new and local end-use markets for waste plastic.
“These requirements ensure that roads are built using quality materials that comply with proven performance criteria, in order to produce durable roads,” he said.
“As such, any new plastic materials or plastic-modified materials utilised in the local industry must be incorporated into road specimens and tested for compliance to the set criteria before they can be implemented in South Africa.”
The use of waste plastic in road construction is not new.
The technology has been used both in Africa and internationally, including Australia, Canada, Ghana, India, Kenya, the Netherlands, New Zealand, Nigeria, the United Kingdom and the United States of America.
However, the South African road construction industry is governed by strict national standards and specifications to ensure the performance of road pavements.
CSIR expert professor Linda Godfrey said the intention is to make sure that this technology is implemented in a responsible manner in South Africa.
“At a time when there is so much attention on the leakage of plastic into the environment, it is important that this technology is implemented in a way that does not cause further environmental harm; for example, through the generation of microplastics from the wear and tear of these road surfaces,” she said.
“We want to support the growth of the waste and recycling sector in South Africa by providing credible evidence to support decision-making.”
First plastic road
The Kouga Municipality in the Eastern Cape begun work on South Africa’s first plastic road in August 2019.
The idea of a plastic road was first mooted by the DA-led municipality as far back as 2016, with the project officially receiving approval at the start of 2019.
Horatio Hendricks, executive mayor of Kouga Municipality, said the local authority had entered a partnership with Scottish company MacRebur and South African civil engineering experts to build ‘the first plastic road’ in Jeffrey’s Bay.
“The backlog in road repairs for our region is estimated to be more than R500-million. While Kouga is strong financially, we simply do not have the rates base to deal with this backlog decisively,” Hendricks said.
MacRebur – which has already tested plastic roads in the United Kingdom and other countries across the globe – will head up the project.
They will receive assistance from Port Elizabeth-based civil engineering and construction companies SP Excel and Scribante Construction.