Caustic Brine Recovery - Sugar Refinery
Case Study
Brine Recovery in Sugar Refinery
In the sugar refining industry, the process of decolorizing raw sugar with high ICUMSA value is crucial. Two methods have been employed for color removal: Granular Activated Carbon (GAC) and Ion Exchange Resin. While GAC is effective in removing color, it is energy-intensive to regenerate. On the other hand, Ion Exchange Resin removes color along with inorganic contaminants but generates large quantities of colored liquid effluents during regeneration.
To address this challenge, the sugar refinery explored various technologies for recycling effluent water, eventually opting for brine recovery using PROMEM Membrine Solution.
Challenges Faced
High energy consumption in GAC regeneration.
Generation of colored liquid effluents during Ion Exchange Resin regeneration.
Inefficient brine recovery with conventional Reverse Osmosis (RO) processes.
Loss of caustic during brine recovery due to the neutralization process.
Technical Issues
The refinery attempted to reduce the brine pH from 12 to 8 so that their Nanofiltration membrane could tolerate the brine solution. However, the membranes could not withstand harsh conditions such as high pH and high temperatures (up to 70°C), leading to regular fouling, flux drop, and color passage issues.
Solution: PROMEM Membrine Technology
Diva Envitec Pvt Ltd, with extensive experience in brine recovery systems, provided high pH- and high-temperature-resistant nanofiltration membranes. These membranes were surface-modified with charge alterations, where Zeta Potential played a crucial role in separation.
Implementation & Results
Brine Flow Capacity: 12 m³/hour (NaOH 2%, NaCl 10%).
Operating Parameters: 8,400 hours/year (24h/day, 350 days/year) at 70°C.
System Retrofitting: Replaced 60 neutral pH membranes with 48 PROMEM membranes.
No Acid (HCl) dosing required, eliminating 1,747 tonnes/year of acid use.
- No Caustic Make up required, as the operation happens at High pH
Higher recovery efficiency: Increased brine recovery from 40-50% to 90%.
Energy Savings: No cooling required for brine processing.
Extended membrane lifespan, eliminating yearly replacements.
Proposed Tubular Reactor to further increase brine recovery to 100%.
Zero Liquid Discharge (ZLD) achieved, eliminating the need for evaporators and ATFD systems.
Key Benefits
Cost & Resource Savings
Caustic Soda Saved: $608,000 per year (neutralization eliminated).
Acid Saved: $554,800 per year.
Energy Saved: $90,972 per year (no heating required).
Total Annual Savings: $1,253,772.
Improved Brine Recovery
Up to 90% brine recovery.
No fouling issues, enhancing membrane efficiency.
No flux drop or choking reported.
Sustainable & Eco-Friendly Process
Minimal chemical consumption.
Efficient color removal, reducing effluent load from 150,000 ICUMSA to as low as 100 ICUMSA.
Zero Liquid Discharge (ZLD) achieved, ensuring 100% brine recovery.
Future Scope
With the success of this implementation, the client is planning an expansion, with Diva Envitec Pvt Ltd as the chosen supplier.
Conclusion
By adopting PROMEM Membrine Solution, the refinery has achieved:
Significant cost savings.
Enhanced process efficiency.
Environmental sustainability.
This innovative solution not only resolves inefficiencies of conventional brine recovery but also sets a new industry benchmark for sustainable sugar refining.
For more information on optimizing your sugar refinery’s brine recovery process, connect with us today!
