Materials News Waste plastics take the high road The world needs more roads as economies expand, development surges, and population increases. The World Bank estimates a total US$34 trillion of road investments required to achieve the global sustainable development goals (SDG) agenda adopted by all UN-member countries. To date, total infrastructure investments are at US$26 million, thus, leaving an US$8 million investments gap.
flooding”. The Zwolle bike path is equipped with sensors to track the road’s performance, including temperature, durability and the number of bike passages. Utilising waste plastics for road building is, however, not a novel concept. In early 2000, Professor Rajagopalan Vasudevan, an Indian scientist from the Thiagarajar Engineering College, Madurai, broached the “frugal technology” concept of modified bitumen with waste plastics. In 2002, he paved a 60-ft road within the Madurai campus with the plastic bitumen mix in ratio of 5 g of plastics per 50 g bitumen. He has since paved 5,000 km of plastic roads in 11 states across India. Vesudevan, who contends that banning plastics has adverse impact on the low income sectors, explains the process of plastic modified bitumen as easy and that requires no complex machines. The plastic wastes are shredded into as small as 2 mm pieces and the shredded plastic is added into the hot aggregate, which is thereafter blended into the bitumen. The plastic coats the stones in a The 30-m long pilot plastic road in Zwolle consists of recycled plastics equivalent to thin film, resulting in good more than 218,000 plastic cups binding. The need for more roads has opened up an avenue The method, aside from helping to stem the for waste plastics to be put in good use, by mixing amount of plastic waste in India, estimated at 62 them up in asphalt and with traditional road building m i l l i o n t o n n e s / y e a r, w i t h o n l y 2 4 % o f w h i c h i s materials (sand, stone, gravel, cement). recycled, according to data from the UNDP (United The PlasticRoad project, a collaboration between Nations Development Programme)” SGP, has also road construction specialist KWS, drainage and water h e l p e d g e n e r a t e j o b s f o r t h e c o u n t r y ’s i n f o r m a l plastic pipes maker Wavin recycling workers, such as the waste or rag pickers. and French oil and gas group Moreover, Vesudevan said that the plastic-modified To t a l , c l a i m s a s t h e w o r l d ’s bitumen improves road strength and reduces road first plastic road. The 30-m fatigue. long pilot plastic road opened in Zwolle, the Netherlands, in Industry initiatives stem plastic waste in Asia September 2018, and consists V i e t n a m i s A s i a ’s f a s t e s t r i s i n g e c o n o m y t h a t of recycled plastics equivalent is hinged on its rapid industrialisation and to more than 218,000 plastic urbanisation. On the other hand, it has also been cups. listed in the 2015 Stemming the Tide report by the According to the partners, Professor Rajagopalan Ocean Conservancy and the McKinsey Centre for Vasudevan's modithe PlasticRoad will “allow for Business and Environment as one of Southeast fied plastic bitumen roads to be built faster with less Asia’s largest marine waste pollution contributor. technology has since impact on the surroundings In 2017 alone, the country generated approximately paved 5,000 km of and less CO2 emissions. The 3 8 , 0 0 0 t o n n e s o f m u n i c i p a l w a s t e s . H o w e v e r, plastic roads in 11 improved drainage will also recycling rates of collected wastes lag at a measly states across India. help to build resilience against 10-15%/year, according to the Vietnam Environment (Screengrab from Youheavy rainfall and reduce Tube) Administration. JULY 2020
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