Sewage Treatment Plants

The Super Trident® sewage treatment plants from Wärtsilä Water & Waste are the cost-effective and safe answer to disposing of waste at sea, maintaining the quality of the world’s oceans.

Our sewage treatment plants are certified to meet IMO MEPC 227(64) guidelines, which will be applicable to new ships from 1 January 2016.

Optimised for the treatment of black and grey wastewater flows, and suitable for conventional gravity and vacuum fed collection systems, all plants are controlled automatically. This allows unattended operation, with reduced maintenance requirements and lower long-term operating costs.

The systems are compact and modular in design, suitable for between-deck installations, and are adaptable to customer new build specifications.


    Benefits of Super Trident® sewage treatment plants

    • Cost-effective, environmental friendly & safe answer to dispose of waste water at sea
    • Proven effluent quality: clean, safe effluent suitable for discharging overboard
    • Low operational costs with:
      • minimal maintenance and spare parts required
      • minimal human intervention during operation
    • Simple & robust construction
    • Compatible with gravity and vacuum collection systems
    • Collecting tank integral part of STP


    Main features

    • IMO & MED certified
    • Single power supply input point
    • Solids handling centrifugal discharge pump
    • Chemical disinfection and dechlorination
    • Automatic control
    • Compact design


    STC 13 line

    System IMO certified
    (LxWxH in mm)
    Weight full
    STC-01-13 1740 1890 1400 1181 1550
    STC-02-13 3120 2518 1863 1336 3030
    STC-03-13 4660 2622 1863 1681 3959
    STC-04-13 6010 2722 2080 1821 5027
    STC-06-13 9360 3072 2280 1971 7367

    STC 14 line

    System IMO certified
    (LxWxH in mm)
    Weight full
    STC-08-14 11840 3000 2670 2000 9294
    STC-10-14 15810 3400 2750 2000 11314
    STC-13-14 20830 4400 2750 2000 15036
    STC-15-14 25704 3700 3215 2300 17836
    STC-20-14 33974 4620 3215 2300 22422
    STC-25-14 40778 4620 3490 2500 27446
    STC-30-14 47422 5012 3470 2700 30898
    STC-40-14 64150 6012 3915 2680 43614
    STC-50-14 80182 7000 4145 2900 55526
    STC-60-14 100800 7000 4180 3500 69754


    As standard

    • Main tank
    • Air compressor
    • Discharge pump
    • Electrical control panel
    • Chlorination & dechlorination systems


    • Fitted vacuum sewage collection equipment
    • Conditioning water flow meter
    • Standby compressor (mounted)
    • Standby discharge pump (mounted)
    • Maceration
    • Separate sewage feed system
    • Retrofit options available to aid installation


    • Asian Hercules II
      “Asian Hercules II”, a 3,200 MT Floating Sheerleg Crane vessel, has 4 main hoisting winches, each capable of hoisting speeds 2m/min with a full load. Delivered in 1997, the vessel has an accommodation facility for 34 persons.

      Asian Hercules II

    • Twister
      The Wärtsilä AQUARIUS® UV Ballast Water Management System (BWMS) was installed onboard the Twister, a Chemgas BV owned LPG carrier.

      For retrofit applications and upgrades, where space availability can be a determining factor, the modular configuration of Wärtsilä’s AQUARIUS® range was a particular advantage and the entire installation process took just 3 weeks.


    • Leonidas
      Delivered in 2009, the 318,000 dwt Leonidas features a machinery installation incorporating a Wärtsilä 7RT-flex82T. The vessel is also equipped with the Super Trident Sewage Treatment Plant ST2A, certified to meet IMO MEPC 159(55) guidelines.


    • HMS Daring
      The HMS Daring, commissioned in 2009, is the first of six vessels of the new Type 45 class. Each Type 45 Destroyer has an IEP (Integrated Electric Propulsion) system consisting of two gas turbine alternators and two Wärtsilä 12V200 diesel alternators. (photo courtesy of BVT)

      HMS Daring

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    Contact us

    Please fill in the form, we aim to respond within 1-2 business days depending on the enquiry. For an existing installation, provide all necessary details to identify the installation and the equipment. Fields indicated with an asterisk (*) are required. 

    For spare parts, please e-mail us with the Equipment Serial Number or the name of the vessel at For urgent support, contact +44 1202 662 693.

    For technical support & service, please email us with the Equipment Serial Number or the name of the vessel at For urgent support, contact +44 1202 662 616.

    Equipment Serial Number is taken from the equipment nameplate and includes all letters and numbers as given on the equipment nameplate.

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