Aquatech is supplying the equipment for two (2) 525 gpm seawater distillation system to Saudi Arabian Oil Company’s Ras Tanura Refinery in Saudi Arabia.
General Project Description
Aquatech was successful in meeting the strict guidelines of Technical & Delivery requirements.
In general the infrastructure was made capable of supporting the needs of up to new 525 US GPM desalination units.
The evaporator is a four effect thermal vapor compression system with the following conditions:
- Seawater temperature range from 48°F to 95°F.
- Seawater TDS 51,000 ppm.
- Distillate (final product from MED unit) purity 5 ppm TDS.
- Design capacity of 525 USGPM with turndown to 50% of design capacity.
Operate at a Gain Output Ratio of 6.5 kg of distillate/ kg of steam input to the thermocompressor
The most important feature of Ras Tanura Project is the Superior Metallurgy of Components of MED plant.
Shell, all 4 effects : UNS S 31254 (SMO 254)
Shell Internals - tubesheets, spray headers, supports : UNS S 31254 (SMO254)
MED Tubes: Titanium
Ejectors : UNS S 31254 (SMO 254)
Valves & Instruments : SMO 254 / SS 317L / Monel etc.
Aquatech’s Multiple Effect (MED) Thermal Vapor Compression design is a 4 effect unit which incorporates SPRAY-FILM technology, a registered trademark of Aquatech. Aquatech’s MED design is the result of over 25 years of experience in the design, manufacture, start-up and operation of MED evaporator systems worldwide.
For this system, steam or water vapor condenses inside horizontal tubes. Seawater is sprayed over the outside of the horizontal tubes and acts as a heat sink for the condensing vapor. The latent heat of vaporization transfers from the water vapor through the tube wall to the thin seawater film on the outside of the tubes. For every pound of water vapor that condenses, approximately one pound of water evaporates from the seawater film once the seawater has reached the saturation temperature.
SPRAY-FILM technology offers superior quality seawater distribution via spray nozzles over the tubes. The spray nozzles ensure that the seawater flows uniformly and generously over the heat transfer surface. The seawater feed flow rate in this system is conservatively designed to keep the heat transfer surface well wetted.