Recycling in the megacity environmental protection in São Paulo

As in every large metropolis, extensive urbanization processes are under way in São Paulo, creating up to 16,000 t of rubble daily. The road rehabilitation programme for the 17,000-km-long road network creates an additional 20,000 m³ of asphalt material each month, which has been stored in refuse dumps up to now. The municipal authorities decided to take action and created a legal basis for the reuse of reclaimed asphalt pavement and construction rubble in the construction of new roads. The cold recycling process is a particularly attractive option here, featuring the complete recycling of the reclaimed material and its cost-effective processing while saving a great deal of time, too. The municipal administration of São Paulo also opted to use reclaimed asphalt pavement (RAP) with foamed bitumen for the current project to rehabilitate the 5-km stretch between the Avenida dos Sertanistas and the Rua Bento Guelfi. “This marked a new departure in urban road rehabilitation in Brazil, where RAP had only ever been used to construct new peripheral roads outside of cities,” explained Antonio Monfrinatti, Managing Director of Reciclotec, the Wirtgen Group’s authorized dealer in São Paulo.

The local road construction contractor Fremix (ANE Group) set up a recycling point in the direct vicinity of the job site for the processing of the construction and recycling materials as well as the RAP. This was where the Wirtgen Group machines really came into their own. Fremix elected to use “in-plant” cold recycling to produce the RAP. In other words, the asphalt removed by a Wirtgen Cold Milling Machine W 1000 F was processed in a mobile plant – the Wirtgen KMA 220 – along with foamed bitumen and then repaved on the roadway. “The plant performed impressively, producing high-quality cold mix from recycled construction materials – CDW (civil demolition waste) – and achieving a high mixing capacity of up to 220 t/h,” concluded Valmir Bonfim, Engineer at Fremix. The KMA 220 was economical in every respect: timeconsuming trips by trucks between the mix production site and the job site were minimized. With an output of 200 t/h, a complete truck load of 20 t of cold recycling mix was produced every six minutes while simultaneously reducing CO² emissions.

Thanks to the efficient cold recycling process the project in São Paulo was concluded swiftly and successfully and the Avenida Sapopemba reopened for urban traffic. The municipal administration of the Brazilian metropolis has raised the bar in urban road rehabilitation with this construction project, setting a shining example to other Latin American city centres.