Alfa Laval - DPU-2 - Two stage freshwater generator

DPU-2 - Two stage freshwater generator

Conversion of seawater into freshwater by vacuum distillation for the supply of high quality freshwater for domestic and process utilization. For installation onboard ships, rigs, and onshore remote locations.

high quality freshwater

DPU-2 benefits

  • Simple and compact design
  • Titanium plate heat exchangers
  • Housing in non coated seawater resistant stainless steel
  • Combined condenser cooling, ejector water and feed water system
  • Freshwater pump and control system

DPU - Two-stage titanium plate type fresh water generator

  • High capacity on waste heat available.
  • High quality freshwater, the low content of dissolved solids (salinity) ensures the supply of pure water which can be used directly as make-up for steam boilers.
  • Long lifespan, the high grade corrosion resistant materials, i.e. the titanium plates, ensure a long lifespan of the equipment.
  • Low operation and maintenance costs. Start-and-forget operation, combined with easy access to the interior, reduces man-hours required for operation and maintenance to a minimum.
  • Simple installation due to compact design, low weight and the possibility to assemble on the spot.

 

 

Kako deluje

DPU, Titanium plate type fresh water generator

Capacity range

The DPU-36-C series covers a capacity range from 10 to 55 m3/24h, depending on the heating medium and cooling water temperatures.

The capacities shown in fig. 1 are capacities at a cooling water temperature of 32°C. The fresh water generator can be dimensioned to suit any jacket water temperature from 55–90°C at any cooling water temperature required.

The quantity of freshwater produced can be altered simply by varying the number of plates in the internal plate heat exchanger.

Working principle

The feed water to be distilled is taken from the sea cooling water outlet of the condenser (1). It enters the evaporator (10) where it evaporates at about 40–60°C as it passes between the plates heated by the heating medium. The evaporating temperature corresponds to a vacuum of 85–95%, maintained by the brine/air ejector (not shown on fig. 2). The vapours generated pass through a demister where any drops of seawater entrained are removed and fall due to gravity to th brine sump at the bottom of the generator chamber. The clean freshwater vapours continue to the condenser (9), where they condense into freshwater as they pass between the cold plates cooled by the sea cooling water.

Installation

The DPU-36-C fresh water generator is designed for automatic operation in periodically unmanned engine rooms and other automated operations.