Porous solid carbon source-supported denitrification in simulated mariculture wastewater

Area of Science:

• Materials Science
• Environmental Science
• Biotechnology

Background:

• Mariculture wastewater poses environmental challenges due to high nitrate levels.
• Developing effective and economical carbon sources for denitrification is crucial for sustainable aquaculture.
• Porous solid carbon materials offer potential for enhanced biological wastewater treatment.

Purpose of the Study:

• To synthesize and characterize a novel porous solid carbon source using semen litchi (SL), poly(vinyl alcohol) (PVA), and sodium alginate (SA).
• To investigate the impact of SL content on the structural properties and denitrification performance of the synthesized beads.
• To evaluate the efficacy of SL/PVA/SA beads as a carbon source for nitrate removal in simulated mariculture wastewater.

Main Methods:

• Preparation of SL/PVA/SA beads via an aqueous method.
• Characterization of bead structure, including surface morphology, pore size, and porosity.
• Evaluation of denitrification performance in simulated mariculture wastewater, assessing acclimation time, nitrate removal rate, and longevity.

Main Results:

• SL/PVA/SA beads exhibited a macroporous network structure with increased surface roughness and uniform pore distribution as SL content increased.
• Porosity decreased with higher SL content, but beads maintained good porosity (e.g., 71.29% for 50% SL).
• Beads showed rapid acclimation and achieved 100% nitrate removal within two days; 50% SL beads demonstrated the longest lifespan and highest denitrification rate (243.5 mg N L⁻¹ d⁻¹).

Conclusions:

• SL/PVA/SA beads are a promising, cost-effective solid carbon source for efficient denitrification in mariculture wastewater.
• Optimizing SL content enhances bead structure and prolongs denitrification efficiency.
• The developed material offers a sustainable solution for treating nitrogen-rich aquaculture effluent.