Mapping and recycling proposal for the construction and demolition waste generated in the Brazilian Amazon.

Abstract

Due to the scarcity of aggregate deposits in the region of the Brazilian Amazon, cities such as Rio Branco (state of Acre) rely on complex logistical operations to guarantee their supply. These operations substantially raise the cost of natural aggregates and, together with their environmental impact, justify the recycling of construction and demolition waste (C&DW) in the region. Therefore, the present study investigates the quantity and composition of the C&DW generated in the urban area of Rio Branco and proposes a recycling plant for the city. Periodic and systematic visits to construction sites were carried out to formulate representative indexes for the generation and composition of the C&DW. These indexes supported an economic feasibility analysis for the recycling plant, as well as a discussion of the environmental impact of this plant on the inert landfill currently used in Rio Branco. As a result, a C&DW generation index per constructed area of 0.22 t/m2 was found for new construction works and 0.41 t/m2 for renovation works, with unit weight of 0.98 t/m3 and 0.92 t/m3

, respec- tively. According to its composition, 100% of C&DW was deemed reusable and/or recyclable. In the last 20 years

(1999 - 2018), 3.2 million tonnes of C&DW were generated in the city, averaging 517 kg/(inhab•year). Economic indicators show feasibility for the installation of a recycling plant with a processing capacity of 90 t/h, improving the environmental, economic, and social aspects of the construction sector in the area.