Horizontal inner Tube Evaporator

The Wärtsilä Horizontal inner Tube Evaporator (HiTE) is a multi-stage evaporator specifically designed for producing small to medium capacities of 30 to 120 tons of distillate per day. It guarantees freshwater for human consumption or clean process water for technical applications. It serves in a wide range of operational areas where alternative technologies like reverse osmosis or plate technology reach their limits. Shallow waters with poor seawater quality is an example of this. 

The HiTE operates smoothly even at partial load, for example during dynamic positioning (DP) operations. The unit’s control system is fully automated, and its smart processes adapt automatically to the amount of energy available. The HiTE is able to utilise waste heat, which is very convenient for vessels with varying engine profiles. The 4-stage HiTE offers up to 75% energy savings with a specific heat consumption of 180 kWh/t compared to single stage designs (700 kWh/t). For a 3-stage HiTE this is 240 kWh/t.  

    • Capacity 30 – 150 t/d
    • Steady production of fresh water at a wide temperature range between 0 - 35°C
    • Flexible in using heat sources with either steam, engine jacket water or a combination of these two
    • Full-automatic or semi-automatic operation
    • Multi-stage design
    • Lowest energy consumption in its range due to the multi-stage design
    • Designed to make maintenance easy for longer operation
    • Unique process optimizes efficiency and dependability
    • Part-load capable makes the HiTE flexible to adapt to demand and/or supply (down to 50%)
    • High quality distillate ≤8 ppm
    Spare parts and service

    Please send the vessel name, equipment type, serial number (if known), your company details and spares and/or service requirements to wsc.aftersales@wartsila.com and we will respond as soon as possible.

    Principles of operation

    In the Horizontal inner Tube Evaporators (HiTE), evaporation takes place inside the tubes. The sea water is fed into the tubes, which is then heated from outside of the tubes either by steam or hot water. The seawater is heated until it reaches boiling temperature inside the tube. Due to both raising temperature as well as decreasing pressure during upstream flow more and more vapour is released. The resulting turbulent fluid/vapour mixture has a very good heat transfer, increasing the efficiency of the unit. The vapour is condensed to the desired distillate of high quality.

    The design uses multiple stages at which seawater is evaporated. The follow-up stage uses the heat from the previous stage to heat up the seawater. This way the energy is recovered, increasing the total capacity of fresh water produced.

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