Volume flow measurement of electrically conductive liquid medium


  • No moving parts, no maintenance and Marine type approvals
  • Standard accuracy ±0.3% of measured value
  • Wear resistant liner


Ballast water treatment onboard a gas carrier

Flow measurement in ballast discharge neutralising systems

A major consequence of global trade is the transport of up to 12 billion tons per annum of ballast water across the oceans. This ballast water is important for maintaining the stability, trim and structural integrity of large marine vessels. However, taking in and later discharging ballast water can potentially transfer invasive aquatic species from one ocean to the next, which can negatively effect local ecosystems and biodiversity. The US Coast Guard (USCG) regulations and IMO Ballast Water Management Convention require ships to implement a ballast water management plan - to ensure that any organisms present in the ballast water are neutralised. Although it is possible to connect to port solutions for treatment of ballast water, it is more common that vessels will install their own fixed systems on board.

Ballast water treatment systems use a variety of technologies, such as filtration, UV irradiation and chemical additives. KROHNE offers a wide range of flowmeters suitable for providing accurate and reliable flow data for feed/discharge lines, in addition to models used to control the dosing of additives within the water treatment systems. The OPTIFLUX 2100 is a cost effective electromagnetic flowmeter ideal for ballast water applications. This range carries marine type approvals from DNV-GL and other major classification societies, comes with an internal pipe liner material suitable for highly aggressive environments, and is available in most nominal bore sizes up to DN1200. These flowmeters offer a full bore obstruction-less design, with no moving parts to wear, and there is no pressure loss in the flow system.