Alternatives for a circular economy: building materials based upon açaí seeds

Açaí fruit is a biologically renewable resource from the Amazon, whose tonnes of seeds are being discarded everyday in the region. However, the promising studies show the great potential of  the seeds in the construction market, responding to the waste problem and strong demand for affordable and local building materials.

The current production of traditional building materials, such as concrete, bricks, and tiles, results in exploration and depletion of natural resources, as well as the consumption of a high amount of energy for extraction, transport, and processing. In addition, in this linear economy model, a large amount of waste is generated.

An economically viable solution to this problem is the utilisation of waste materials for new products, which radically limits the extraction of raw resources and minimises the amount of waste discarded into the environment. In this way, each material is recovered and reused in cyclical flows, over and over again, which allows its trajectory from cradle to cradle, preserving and transmitting its value. For this purpose, research is being carried out towards exploring solutions aimed at reusing resources to produce sustainable and environmentally friendly construction materials. Examples of such initiatives are being developed in the Amazon, around açaí (Euterpe oleracea), the most consumed fruit in the region.
According to the World Trade Organization (WTO), around 90% of all açaí consumed in the world is produced in the state of Pará, Brazil. In 2018, the total production of açaí in Pará was around 1.4 million tons, with approximately fifty thousand families participating in the process. The production generates almost 450 million USD per year, representing 70% of the income source of the riverside population and generating employment for thousands of families who work in the fruit processing factories in the city of Belém [1].

However, only 4% of the fruit´s total weight, the pulp, is used by the industry. The rest, mainly the seeds, remains without a defined utility and is commonly discarded. This creates a considerable problem for the region, as the volume of waste produced is high: the state government of Pará estimates a total volume of around 1.6 to 2 tons per day, whose disposal is made mainly in open sky landfill sites [1]. With this problem in mind, the researcher Francielly Rodrigues Barbosa in association with Beatriz Cintra, architect and researcher from the University of São Paulo, developed a project in which they use a valuable raw material – açaí seeds – to produce low-cost bricks. In this way, they create an alternative for low-income populations in the peripheries of the Amazon cities, who could not afford to buy traditional building materials.