Waste Heat Distiller
Aqua-Chem has more than 40 years of experience supplying watermakers to naval forces. We offer a range of plate-type distillers for use on naval supply ships. Aqua-Chem is currently delivering 53 tpd units for installation on the T-AKE, Lewis and Clark Class dry cargo ships, a solution proven to provide high-purity distilled water for ship systems and hotel services as well. An older version of this unit, designed to produce 38 tpd, is in use on the T-AO, Kaiser Class fleet replenishment oilers.
Heat Source – Diesel engine jacket cooling water, Steam, Hot Transfer Oil is used to supply heat to the unit. Use of "waste heat" requires little or no additional energy input. If necessary, supplemental steam or electric heaters can be provided to compensate for insufficient heat during low engine load operations.
Pumps and Motors – Aqua-Chem typically provides the seawater feed pump and the distillate pump. The pumps are manufactured using corrosion-resistant alloys, and the motors are industrial marine-grade Totally Enclosed Fan-Cooled (TEFC) motors.
Materials of Construction – We use corrosion-resistant, duplex stainless steel, copper-nickel and stainless steel for the shell and piping, and titanium plate packs for the heat exchanger.
Automation – Watermakers are designed for simplicity of operation. Units are controlled by manual startup and shutdown with automatic operation. Product water is continuously monitored with automatic diversion if salinity exceeds programmed limits.
Accessories/Options – Remineralizers, hydrophores, UV sterilizers, booster pumps, electric heaters and other options are available on request.
- Compact units with simple operation.
- Use of waste heat requires little or no additional energy input.
- Low-temperature operation reduces corrosion and scaling potential.
- Reliable and durable materials with proven performance after more than four decades of marine use.
- Local start and automatic operation with automatic safety shutdowns. Product water is continuously monitored with automatic diversion if salinity exceeds programmed limits.
- Factory tested to ensure trouble-free startup.
How Aqua-Chem Seawater Plate Distillers Work
- Seawater first passes through the condenser on one side of each plate in the upper plate pack. It condenses the water vapor into distilled water on the other side of each plate.
- About 10 percent of incoming seawater is then diverted to the evaporator or lower plate pack of the distiller.
- The heating water from the waste heat source passes through the evaporator and heats the seawater to boiling. Since the unit operates at a vacuum, the seawater boils at 120° F to 140° F.
- The water vapor rises toward the top of the unit and passes through a wire mesh mist eliminator before entering the upper plate pack and condensing into distilled water.
- Distilled water collected in the upper plate pack drains to the distillate pump. Before being pumped to the storage tank, the conductivity is continuously monitored and automatically dumps to drain if the conductivity is too high.
- The bulk of the seawater flows through the eductor. The seawater drives this suction device which draws vacuum, removes air and gases from the water vapor, and removes concentrated seawater from the bottom of the distiller.