Cathelco BWMS for Harvey offshore vessel
The Harvey Stone, a Rampage 6400 multi-purpose field support vessel (64.8m loa; 18m beam), is due to be delivered in Q2 2016. The BWMS will have a capacity of 150m3/hr.
The Cathelco system received IMO type approval in May 2014 and went on to gain AMS (Alternate Management System) acceptance from the US Coast Guard a few months later. Cathelco’s agent in New Orleans, Green Marine & Industrial Equipment Co, won the Harvey order.
Peter Smith, sales director of Cathelco, noted that the company is one of just a few UV system suppliers with no restriction on the salinity of waters in which its equipment can function. “Our system has been approved and accepted to work in marine, brackish and fresh water, allowing vessels to enter the Great Lakes and other inland waterways,” he noted.
The AMS approval recognises that the system will continue to function with UV light transmittance values as low as 45% (seawater typically boasts transmittance of around 75%).
Cathelco’s BWT systems are available with capacities from 34m3/hr to 1,200m3/hr in a single unit. The system automatically adjusts to different sea water qualities, measuring turbidity as well as UV light transmittance – is a far more reliable parameter for calculating the UV dose as well as ensuring that power is used economically. Stepless power control ensures that UV power is used as economically as possible.
Cathelco notes that its UV chambers are some of the smallest on the market. Each unit is a twin chamber with two lamps, doubling UV exposure. A helix-shaped water flow ensures increases the surface area of water exposed to the UV lights.
An innovative system uses special cleaning balls to remove residue from the quartz sleeves and internal surfaces of the chamber. No chemicals are therefore used in operation or cleaning, and there are no mechanical parts to scratch the surface of the sleeves.
