OceanSaver said it has received a rush of ballast water treatment (BWT) system orders for large vessels. The Norwegian firm, a BWT specialist developing solutions since 2003, has won orders for more than 40 systems in the last six months, with some 21 units delivered so far this year. The latest contracts, worth approximately $30 million, cover a diverse range of large tonnage, from a number of key international markets, with VLCCs, Aframax tankers, product tankers and Cape Size bulk carriers.