Microalgae based wastewater treatment: a shifting paradigm for the developing nations.

Area of Science:

• Environmental Science
• Water Treatment Engineering
• Microbiology

Background:

• Untreated wastewater disposal causes eutrophication and water scarcity.
• Conventional wastewater treatments are costly and inefficient at nutrient removal.
• Developing countries face challenges with expensive and ineffective aerobic secondary treatments.

Purpose of the Study:

• To assess the effectiveness of Chlorella vulgaris for municipal wastewater treatment.
• To evaluate nutrient and physico-chemical parameter removal efficiencies.
• To explore a cost-effective and eco-friendly wastewater treatment alternative.

Main Methods:

• Lab-scale batch study using primary treated municipal wastewater effluent.
• Utilized Chlorella vulgaris for treatment with a 7-hour detention time.
• Analyzed parameters: pH, EC, TDS, TSS, TS, COD, phosphate, ammonia, nitrate, and DO.

Main Results:

• Chlorella vulgaris achieved high removal efficiencies: 98.32% phosphate, 97.26% ammonia, and 84.71% COD (non-filtered).
• Filtered effluent showed even higher removal: 98.53% phosphate, 98.63% ammonia, and 89.41% COD.
• Significant reduction of organics and nutrients below desirable limits was observed.

Conclusions:

• Microalgal treatment with Chlorella vulgaris is effective for municipal wastewater.
• This method offers a sustainable, energy-saving, and cost-effective solution, especially for developing nations.
• Chlorella vulgaris can reduce effluent nutrient and organic concentrations without external aeration.