From 35,000+ TDS Seawater to Drinking Water: A Desalination Solution for a New Resort in Zanzibar
The Challenge
A new resort in Zanzibar faced a significant water challenge: their main water source was seawater with TDS exceeding 35,000 mg/L.
The resort had limited freshwater and needed a dependable source of drinking water.
Thus, the resort required a desalination system that could convert seawater into usable water efficiently, while maximizing recovery.
The Alantech Solution
According to the conditions of the site, Alantech has created a multi-stage seawater desalination system.
Treatment Procedure:
Sea Water → Chlorination → DAF → pre-filtration → RO → Second Stage RO → Treated Water
Designing Treatment Around the Water
RO cannot perform seawater desalination alone.Proper conditioning of the feed before it reaches the membranes is required to protect the RO system and to ensure stable operation.
Alantech designed a treatment train for this resort which starts with chemical pretreatment, dissolved air flotation and prefiltration followed by a multi-stage RO process.
Key treatment stages
Chlorination: primary treatment and biological control.
DAF: Suspended and floatable pollutant removal.
Prefiltration: extra RO membrane protection.
1st Stage RO: Sea water desalination > 35000 TDS, 40% recovery.
Second-Stage RO: Further water recovery, achieving a recovery of about 80% at the process conditions given.
From Seawater to a Trustworthy Drinking Water Source
The ultimate goal wasn’t just to make desalinated water.
It was producing a consistent water source for the resort’s drinking water requirements.
Therefore, the treatment system was designed as a complete process, not as a stand-alone RO installation.
More Than RO. A Total Desalination Solution.
This project is an example of an important principle in seawater desalination:
Desalination starts successfully before the RO membrane.
Alantech has developed a solution that focuses on water quality, membrane protection and enhanced water recovery by combining appropriate pretreatment with multi-stage RO configuration.
Got a seawater desalination challenge?
Alantech designs and builds custom desalination systems for resorts, hotels, industrial and coastal projects tailored to your water quality, capacity and application needs. Your water source may be sea water. It doesn't have to be a difficult solution.Contact Alantech for your Seawater Desalination Requirement.
