A pioneering environmental decontamination project in Rio de Janeiro’s polluted Marapendi Lagoon is demonstrating the potential of an integrated ecological and industrial solution. Led by Professor Felipe Landuci, the initiative focuses on the cultivation of local filamentous algae, which thrive in nutrient-rich, polluted waters. The algae act as a natural bio-remediation agent, effectively “cleaning” the lagoon by absorbing and sequestering excess nutrients originating from sewage discharge, a primary cause of the lagoon’s degradation.

The project, which began in March and has already completed two harvests, utilizes a 75 m² floating raft system. The primary goal is to quantify the amount of nutrients removed from the water column and to explore the economic viability of the resulting biomassBiomass is a complex biological organic or non-organic solid product derived from living or recently living organism and available naturally. Various types of wastes such as animal manure, waste paper, sludge and many industrial wastes are also treated as biomass because like natural biomass these More. The harvested algae represent a valuable resource, as they are rich in nitrogen, phosphorus, and potassium, making them an excellent organic fertilizer for agricultural applications.

Of particular interest to the biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More sector is the conversion of this algal biomass into biochar. This process, which involves heating the material in a low-oxygen environment, yields a stable, carbon-rich substance. The resulting biochar has a variety of high-value applications, including use as a soil amendmentA soil amendment is any material added to the soil to enhance its physical or chemical properties, improving its suitability for plant growth. Biochar is considered a soil amendment as it can improve soil structure, water retention, nutrient availability, and microbial activity.   More to improve fertility and water retention, as a component in water filtration systems, and as a clean-burning solid fuel. This project highlights a novel and sustainable approach to waste valorization, turning a significant environmental problem—eutrophication—into a profitable resource stream. The project’s success has garnered approval for expansion from the Municipal Secretariat of Environment and Climate, signaling strong support for this green technology and its potential to benefit both the environment and local economy, including a noted increase in fishing production within the lagoon.

SOURCE: Algae is tested in Marapendi Lagoon for effective environmental depollution