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Crystallization of Membrane Proteins in Lipidic Mesophases
Published on: March 28, 2011
Assessing struvite precipitation in a pilot-scale fluidized bed crystallizer.
M Iqbal1, H Bhuiyan, D S Mavinic
1Environmental Engineering Group, Department of Civil Engineering, University of British Columbia, Vancouver, BC, Canada.
Environmental Technology
|November 4, 2008
Summary
Recovering phosphate as struvite from wastewater using a fluidized bed reactor is cost-effective. Optimal conditions ensure high phosphate removal and pure struvite product, minimizing operational issues.
Area of Science:
- Environmental Engineering
- Chemical Engineering
- Water Treatment Technologies
Background:
- Phosphate recovery from wastewater is crucial for resource management and pollution control.
- Struvite crystallization offers a viable method for phosphate removal and nutrient recovery.
- Biological wastewater treatment plants generate effluents suitable for struvite precipitation.
Purpose of the Study:
- To evaluate the effectiveness of a pilot-scale fluidized bed reactor for phosphate recovery via struvite crystallization.
- To determine optimal operating parameters for maximizing phosphate removal and product purity.
- To investigate the impact of specific ions and organic ligands on struvite precipitation.
Main Methods:
- Utilized a pilot-scale fluidized bed reactor at the University of British Columbia (UBC).
- Controlled pH (8.0-8.2) and recycle ratios (5-9) to manage supersaturation.
- Employed the PHREEQC model to assess the influence of acetate on struvite precipitation.
- Analyzed the effects of calcium and carbonate ions on crystallization.
Main Results:
- Achieved effective phosphate recovery from anaerobic digester centrate as nearly pure struvite.
- Optimal reactor performance observed at a supersaturation ratio of 2-6.
- Magnesium to phosphate and ammonium to phosphate molar ratios were critical for system performance.
- Acetate concentrations below 100 mg/L did not significantly inhibit struvite precipitation.
- Calcium and carbonate ions did not affect struvite purity due to kinetic control of their precipitation.
Conclusions:
- The fluidized bed reactor is an effective technology for cost-effective phosphate recovery from wastewater.
- Precise control of operating parameters is essential for maximizing efficiency and product quality.
- Struvite crystallization can yield high-purity products with minimal interference from common ions and organic ligands.
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