New Delhi: In a first for India’s national highway sector, waste plastic has been mixed directly with bitumen in a pilot road section on NH-44 in Jhansi, Uttar Pradesh, in an effort to find a new use for plastic waste while reducing conventional bitumen consumption.
The pilot stretch was laid on Thursday using Waste Plastic Modified Bitumen (W-PMB 76-10), a technology developed by IIT (BHU), Varanasi, under a research programme funded by the Ministry of Road Transport and Highways.
Officials associated with the project said the technology could reduce conventional bitumen consumption by around 4%. The modified material is also estimated to cost about 20% less than conventional bitumen, although its performance and suitability for wider use will depend on the results of long term field monitoring.
Under the new wet process technology, processed waste plastic is mixed directly with bitumen before the material is used for road construction. This differs from the method previously used in India, where waste plastic was incorporated as a dry mix with aggregates during construction of the bituminous layer.
The pilot stretch will be monitored by IIT (BHU) to assess its engineering performance and durability under actual road conditions.
The technology uses low density polyethylene (LDPE) a common plastic found in discarded irrigation pipes, files and plastic folders. The waste material is processed with the involvement of local recyclers and micro, small and medium enterprises creating a potential link between plastic recycling and road infrastructure.
India generates around 25,000 tonnes of plastic waste every day according to the report. The new approach could provide an additional avenue for using some of this waste in infrastructure projects.
Laboratory testing cited by officials has indicated that LDPE modified bitumen can offer greater resistance to moisture damage and rutting at high temperatures. The modified binder increases the stiffness and high temperature performance of asphalt, which could help pavements withstand deformation under heavy traffic and high ambient temperatures.
The technology has also received a patent.
However the Jhansi road section is still a pilot project. Its long term durability, environmental performance maintenance requirements and economic benefits will need to be assessed through continued monitoring before the technology can be considered for wider deployment across national highways.
If the field trials demonstrate the expected performance, the technology could potentially contribute to both plastic waste management and reduced demand for conventional bitumen in road construction.