Nature-based solutions for wastewater treatment and bioenergy recovery: A comparative Life Cycle Assessment.

The aim of this study was to assess the environmental impacts of up-flow anaerobic sludge blanket (UASB) reactors coupled with high rate algal ponds (HRAPs) for wastewater treatment and bioenergy recovery using the Life Cycle Assessment (LCA) methodology. This solution was compared with the UASB reactor coupled with other consolidated technologies in rural areas of Brazil, such as trickling filters, polishing ponds and constructed wetlands. To this end, full-scale systems were designed based on experimental data obtained from pilot/demonstrative scale systems.

Wastewater-based epidemiology for preventing outbreaks and epidemics in Latin America - Lessons from the past and a look to the future.

Wastewater-based epidemiology (WBE) is an approach with the potential to complement clinical surveillance systems. Using WBE, it is possible to carry out an early warning of a possible outbreak, monitor spatial and temporal trends of infectious diseases, produce real-time results and generate representative epidemiological information in a territory, especially in areas of social vulnerability. Despite the historical uses of this approach, particularly in the Global Polio Eradication Initiative, and for other pathogens, it was during the COVID-19 pandemic that occurred an exponential increase in environmental surveillance programs for SARS-CoV-2 in wastewater, with many experiences and developments in the field of public health using data for decision making and prioritizing actions to control the pandemic.

Reduction and liquid-solid partitioning of SARS-CoV-2 and adenovirus throughout the different stages of a pilot-scale wastewater treatment plant.

Investigating waterborne viruses is of great importance to minimizing risks to public health. Viruses tend to adsorb to sludge particles from wastewater processes by electrostatic and hydrophobic interactions between virus, aquatic matrix, and particle surface. Sludge is often re-used in agriculture; therefore, its evaluation is also of great interest to public health.

Relationships between abiotic and biotic variables in a maturation pond and their influence on E. coli removal.

The effects of depth and climate seasonality on zooplankton, algal biomass, coliforms and Escherichia coli in a small full-scale shallow maturation pond receiving pre-treated domestic wastewater were evaluated during a tropical climatic seasonal cycle. The experiment revealed that the zooplankton community was dominated by rotifers and protozoans, and concentrations were influenced by seasonality. A negative correlation between zooplankton, and pH, dissolved oxygen, temperature and ultraviolet radiation, and chlorophyll-a and Escherichia coli were observed at all depths.

Effect of digestate loading rates on microalgae-based treatment under low LED light intensity.

Low red-LED irradiances are an attractive alternative for enhancing microalgae photobioreactors treating digestate due to their potential contribution in decreasing area footprints with low energy consumptions. However, more information is required regarding the influence of digestate load on treatment performance and biomass valorisation when low-intensity red-LEDs are applied. Thus, this study assessed microalgae-based photobioreactors treating food waste digestate under different concentrations (5%, 25%, 50%, and 75%, v/v) at low red-LED irradiance (15 µmol·m·s).

Planning for achieving low carbon and integrated resources recovery from sewage treatment plants in Minas Gerais, Brazil.

There is an enormous deficit in sanitation infrastructure in most Brazilian cities. To tackle this challenge, it is crucial to conceive the new sanitation infrastructure based on sustainability principles, including an integrated approach for the management of the liquid, solid and gaseous phases. This study aimed at developing sustainable sewage treatment flowsheets for different scales and regional scenarios in the state of Minas Gerais.

Treatment of food waste digestate using microalgae-based systems with low-intensity light-emitting diodes.

Anaerobic digestion of food wastes coupled with digestate post-treatment using microalgae-based systems could recover large amounts of energy and nutrients worldwide. However, the development of full-scale implementations requires overcoming microalgae inhibition by high ammonia concentrations and low light transmittances affecting photosynthesis. This study evaluated the potential of microalgae-based reactors supplied with red light-emitting diodes (LEDs) at low intensity (660 nm and 15 µmol·m·s) to treat food waste digestate.

Effect of temperature on microbial diversity and nitrogen removal performance of an anammox reactor treating anaerobically pretreated municipal wastewater.

The effects of temperature reduction (from 35 °C to 20 °C) on nitrogen removal performance and microbial diversity of an anammox sequencing batch reactor were evaluated. The reactor was fed for 148 days with anaerobically pretreated municipal wastewater amended with nitrite. On average, removal efficiencies of ammonium and nitrite were high (96%) during the enrichment period and phases 1 (at 35 °C) and 2 (at 25 °C), and slightly decreased (to 90%) when the reactor was operated at 20 °C.

Microalgae harvesting and cell disruption: a preliminary evaluation of the technology electroflotation by alternating current.

Some species of microalgae have high productivity and lipid content, which makes them good candidates for biodiesel production. Biomass separation and cell disruption are important steps in biodiesel production from microalgae. In this work, we explored the fundamentals of electroflotation by alternating current (EFAC) with non-consumable electrodes to simultaneously harvest microalgae and disrupt cells from mixed microalgae obtained from waste stabilization ponds.