Testing beyond IMO

Wilhelmsen Technical Solutions says that there is general concern in industry about insufficient information on the operation of ballast water treatment systems (BWTS) in real life conditions. The company took this into consideration during the IMO testing of the Unitor BWTS.

According to Wilhelmsen, in order to make a test more difficult, one can either make the test conditions more demanding, or use more challenging test methods. Wilhelmsen says it, and Resource Ballast Technologies, the  technology provider for the Unitor BWTS, did both.

The IMO BWTS test protocol specifies ‘challenge water’ conditions. These detail the minimum numbers of various organism types and water characteristics, such as suspended solids, per unit volume in the water that must be tested. In the land-based testing of the Unitor BWTS, where the challenge water make-up could be controlled, the parameters were set far above the minimum requirements. Despite testing at multiple times the required level, the system met IMO’s D2 performance standards.

One demanding testing method employed was the use of a FlowCAM for analysis during shipboard trials. In parallel testing it was found that the FlowCAM recorded higher organism counts than those found when the samples were sent to a laboratory for analysis. It is thought that this is because some organisms died in transit. Wilhelmsen believes that few, if any, other systems have been subject to such stringent shipboard analysis.

The Unitor BWTS is a fully inline system treating ballast water on intake only. With what is claimed to be one of the smallest footprints and lowest power consumptions in the market, it is said to be a flexible and economical solution for both newbuilds and retrofits.

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