Recycled plastic has many fields of application, one of them is the creation of road surfaces. There are about 40 million km of roads on the planet, 1.6 trillion tons of asphalt are spent annually on expanding this network and creating new highways. One of the main components of the asphalt mix is bitumen, the content of which varies from 10 to 60%. Partial replacement of this material with recycled plastic will solve the problem of environmental pollution and improve the practical characteristics of the road surface.
In 2002, engineers at the Indian company KK Plastic Waste Management Ltd patented the technology for using plastic waste in road paving.
This company owns a plant in Bangalore that processes today up to 30 metric tons of plastics per day.
It took the Indians 5 years to develop the technology for processing PET bottles, plastic glasses, and bags into a component of the asphalt mix.
The company created the KK Poly Blend polymer blend, which replaces 8% of bitumen in the asphalt mix and improves the performance of the road surface.
The lifespan of roads created on the basis of this material is doubled. KK Plastic Waste Management Ltd built 2,000 km of roads and recycled 8,000 tons of plastic waste.
From India, the idea migrated to Western Europe, one of the leaders of the Scottish company MacRebur brought it to his country and after 18 months of research patented highly effective additives based on recycled plastic. They are available in the form of granules and flakes, which are added together with bitumen in the production of coatings.
The modified asphalt mix becomes 60% stronger, and the canvas based on it serves 10 times longer.
The leaders in the production of plastic asphalt in North America are Canadians. Green Mantra has developed an innovative technology that allows you to use up to 20% recycled plastic when creating a roadway.
Modified asphalt concrete is actively used today for laying and repairing roads in Vancouver.
Road Technology: Components and Laying
The process of creating building material for pavement goes in several stages:
• collection, sorting and treatment of plastic waste;
• grinding of polymeric materials;
• adding crushed and molten plastic to bitumen;
• heating the mixture and applying it to the aggregate at a temperature of 160 degrees;
• bitumen treatment;
• Adding a mixture of plastic to improve grip.
The result is an asphalt mix, which is laid on the prepared base in a classic way. Pavers are used to compact and create a perfectly even blade.
A unique innovative technology for the use of plastic waste is developed by the Dutch company VolkerWessels.
It consists in casting from recycled plastic hollow slabs for the roadway. In the voids, it is planned to lay urban communications. Plates on such plastic roads will be stacked on a pad of compacted sand.
A distinctive feature of the technology is the use of a large amount of waste, as well as quick installation.
Russian experts analyzed the potential of this system and came to the conclusion that such a plastic road surface can be used in the climatic conditions of our country only for the construction of sidewalks and park paths.
How to make a do-it-yourself coating?
Fans of the tradition of doing everything with their own hands can reproduce the technology for the production of asphalt from plastic.
The resulting material can be used for minor repairs to the canvas in the parking lot near a private house or cottage.
To work, you need to collect plastic bottles, remove corks and labels.
The crushed plastic is heated to the melting temperature. The waxy mass is poured into preheated bitumen, gravel is added and mixed.
The resulting mixture is poured into a pit or crack, heated with a burner for laying the surfaced roof and rammed.
Advantages and disadvantages
The main advantage of using plastic waste to create a pavement is the improvement of the environmental situation in large cities.
The high potential for plastic consumption by road companies is a stable and constant disposal of garbage polluting not only big cities, but also the world's oceans.
Among the advantages of a road surface with plastic:
• increased strength;
• high water resistance;
• increasing the intervals between repairs;
• reduction in operating costs;
• high tensile strength;
• operation at temperatures in the range from -40 to + 80ºС;
• good grip on the wheels of cars;
• increased resistance to engine oil and fuel;
• reduction of deformation of the coating and the absence of gauge;
• minimum number of cracks due to plasticity of plastic;
• long term of operation.
Externally, the coating does not differ from traditional asphalt concrete.
Benefits of using recycled plastic coatings for cities:
• reduction of road maintenance costs;
• minimum costs for the modernization of asphalt plants;
• the cost of asphalt is lower than when using coatings with modified bitumen;
• reduction of waste disposal costs at landfills.
Roads with asphalt based on plastic bottles and other waste will improve the socio-economic status of the city.
Among the disadvantages of the coating:
• the cost is 3% higher than the usual asphalt concrete pavement;
• deterioration in performance at high temperatures;
• lack of a regulatory framework for the implementation of coverage.
The production requires a large amount of plastic waste - you need a separate waste disposal system.
Road surfaces based on recycled plastic waste are one of the most promising areas for the development of road construction. It is possible that this area will soon become one of the stable sales channels for the plastic processing business.
The use of innovative materials will help reduce the cost of laying and maintaining highways, rid cities of plastic waste.
Plastic roads in Russia
Technologies for the use of recycled polymer materials in road construction in Russia were developed by the company Rusnano OJSC.
The Innovation Road program was created, within the framework of which new coatings were to be used in the construction of highways in Tatarstan, Moscow, and the Ryazan Region.
The project remained at the development stage, faced with the need to adjust GOSTs, SNiPs, and technical regulations.
In Russia, they improve the quality of pavement for roads with the help of plastic additives developed by SIBUR Holding.
Polymer-bitumen binders are produced from petroleum products.
Recycling of plastic is not implemented in the company, due to the high costs and lack of implemented technologies in the country for the massive collection of polymer waste.
Technologies similar to Indian and Canadian are being developed in Yaroslavl and Novosibirsk. It is planned to use asphalt mixes based on recycled plastic for road repairs, and in the future for laying highways.
For the implementation of projects, the introduction of technologies for the collection and sorting of plastic waste, a change in existing legislation is required.