Evaluation of the cultivation of the microalga Chlorella minutissima in landfill: bioremediation potential and production of chlorophyll and carotenoids

• Grant number: 24/17299-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2025
• End date: February 28, 2026
• Field of knowledge: Engineering - Chemical Engineering - Chemical Technology
• Principal Investigator: Daniela Helena Pelegrine Guimarães
• Grantee: Beatriz dos Santos Faria
• Host Institution: Escola de Engenharia de Lorena (EEL). Universidade de São Paulo (USP). Lorena , SP, Brazil

Abstract

The amount of solid waste disposed of has increased in recent decades, resulting in higher generation of leachate in landfills, a liquid derived from decomposition and containing toxic substances that can contaminate soil and water, raising environmental concerns. In response, society seeks sustainable solutions for leachate treatment, such as the use of microalgae as a cultivation medium in the bioremediation process. These organisms metabolize nutrients from leachate, contributing to its bioremediation and allowing for biomass production, which can be utilized in bioenergy and biofuels. Microalgae of the Chlorella genus are particularly effective in this process, helping to reduce toxicity and valorize the generated resources. The main objective of this project is to assess the bioremediation potential of the microalga Chlorella minutissima cultivated in landfill leachate, as well as to optimize pigment production from this species in a semi-continuous reactor. Initially, it will be necessary to study the behavior of the microalga will be studied in a batch reactor, where the effects of leachate concentration, CO2 concentration in the culture feed, aeration flow rate, and LED wavelength will be evaluated using a Taguchi L9 orthogonal array. The response variables will include bioremediation potential and biomass and pigment productivity. Following the results from batch cultures, cultivation in a semi-continuous reactor will be initiated, aiming to increase biomass and pigment productivity. The effects of the same variables, along with feed flow rate, will be analyzed after determining the specific growth rate from batch cultures. The bioremediation potential of Chlorella minutissima will be evaluated using DQO techniques and heavy metal analysis.