Reverse Osmosis Membrane Performance Analysis
Investigated the effects of operating pressure on water and salt transport in single and double membrane RO configurations using NaCl feed solutions. Determined water permeability, salt permeability, and rejection coefficients to optimize membrane performance for desalination applications.
Technical Skills Demonstrated
Membrane Process Operation
- Single and double membrane RO system setup
- NaCl feed solution preparation and handling
- Pressure variation (20-74.7 psi operating range)
- Cascade configuration with retentate recycling
Analytical Characterization
- Conductivity sensor calibration (6 calibration curves)
- Linear regression analysis (R² > 0.99)
- Salt concentration determination (0-20,000 µS/cm)
- Real-time monitoring and data collection
Transport Phenomena Analysis
- Water permeability coefficient calculation
- Salt permeability coefficient determination
- Rejection coefficient quantification
- Solution-diffusion model application
Process Performance Evaluation
- Selectivity ratio analysis (A/B ratios)
- Water recovery optimization (42% vs 68%)
- Membrane configuration comparison
- Trade-off analysis (permeability vs selectivity)
Key Performance Metrics
1.29×10⁻⁴
Single Membrane Water Permeability
m/(s⋅bar) with superior salt selectivity performance
3.28×10⁻⁴
Double Membrane Water Permeability
m/(s⋅bar) - 2.5× increase over single membrane
4.31 bar⁻¹
Single Membrane Selectivity
A/B ratio demonstrating superior desalination efficiency
Engineering Trade-offs: Single membrane configurations demonstrated superior selectivity (A/B = 4.31 bar⁻¹) with lower salt permeability (3.64×10⁻⁵ m/s vs 9.01×10⁻⁵ m/s), making them optimal for high-purity desalination. Double membrane systems achieved 68% water recovery compared to 42% for single membranes, but at the cost of reduced salt rejection efficiency. The analysis provides critical design parameters for optimizing RO systems based on water quality versus quantity requirements.
Complete Research Report
Detailed methodology, conductivity calibration, and membrane performance analysis