Industrial Symbiosis in Wastewater Treatment Plants

Tiago José de Oliveira Casaleiro

Key information

Authors:

Tiago José de Oliveira Casaleiro (Tiago José De Oliveira Casaleiro)

Supervisors:

Cristina Galvão Ascenço; Ana Paula Vieira Soares Pereira Dias (Ana Paula Vieira Soares Pereira Dias)

Published in

September 21, 2021

Abstract

The world population is increasing, as a result, natural resources are increasingly exploited, and more and more waste is produced. It is predicted that by 2050, the amount of resources equivalent to three planets Earth will be consumed. We currently live in a linear economy and there is a need to disconnect economic growth from environmental stresses, and that is where the concept of the Circular Economy came from. A Circular Economy implies the production of high-quality products that are functional, safe, efficient, and affordable. These products are provided to citizens to have greater durability and can be reused, repaired, or even recycled with a guarantee of high quality. Industrial Symbiosis can be seen as a tool to achieve a Circular Economy, since it advocates the recovery of waste from one industry, which are called by-products, using them as raw material for another industry. The sludge produced in wastewater treatment plants can be valorised in the context of Industrial Symbiosis, having various uses such as energy recovery, application in agricultural soil, nutrient recovery, heavy metal extraction, production of building or construction materials, enzyme recovery, production of bioplastics (PHAs), biopesticides production, protein extraction, and production of adsorbent materials. With the growing number of wastewater treatment plants in the world, the production of sludge has increased and is a concern. So, wastewater treatment sludge from three different industrial sectors (municipal wastewater treatment, wine production and diary production) were highlighted due to their potential to be valorised.