Microalgae and wastewater treatment

Area of Science:

• Environmental Science
• Biotechnology
• Aquatic Ecology

Background:

• Aquaculture wastewater poses environmental challenges due to high organic load and nutrient content.
• Microalgae are increasingly recognized for their potential in wastewater treatment and resource recovery.

Purpose of the Study:

• To evaluate the efficiency of a microalgae-based system for treating aquaculture wastewater.
• To assess the removal of chemical oxygen demand (COD), biochemical oxygen demand (BOD), nutrients, and heavy metals.
• To analyze the impact of wastewater on the amino acid profile of microalgae.

Main Methods:

• Utilized microalgae species Scenedesmus and Chlorella in batch and continuous culture systems.
• Monitored key water quality parameters including COD, BOD, phosphorus, nitrogen, ammonia, and heavy metals.
• Analyzed the amino acid composition of microalgae grown in wastewater versus synthetic media.

Main Results:

• The microalgae system significantly reduced COD and BOD below discharge limits.
• Complete removal (100%) of phosphorus, nitrogen, and ammonia was achieved.
• Heavy metal removal efficiencies ranged from 52.3% to 100%.
• Wastewater enhanced the content of specific amino acids (Asp, Thr, Ser, Glu, Gly, Tyr, Pro) in microalgae.

Conclusions:

• Microalgae aquaculture wastewater treatment systems are highly effective in pollutant removal.
• These systems offer a sustainable solution for aquaculture wastewater management.
• Wastewater cultivation alters microalgal nutritional composition, potentially impacting their use in other applications.