seatec - Finnish marine technology review 1/2012 | Page 50

NEW ON BOARD CHALLENGES IN CONVERSION PROJECTS C onversions are a big part of every cruise ship’s life. Reasons need attention as well; sometimes the existing systems do not al- for conversions are many: keeping the vessel attractive to low expansions, or there is not enough capacity left for planned passengers, increase the earning capacity, update the technolo- conversion. gy, reduce energy consumption or improve stability among others. Additional challenges in conversions are the availability of To verify the feasibility of any significant conversion, the two drawings: typically it is difficult or even impossible to get hold of most important items to check are escape arrangements and sta- all the original drawings. Also following rules and regulations is bility; if the staircases are not wide enough it is often better to not that straightforward: often you cannot – and should not – reconsider the conversion scope. Similarly, if a conversion needs follow the current regulations, but you have to know what reg- a sponson-ducktail due to stability, it is better to know this well ulations were in force when the ship was built. in advance. Even if conversions are often more challenging than new- Even if easier to solve, structural fire protection is an impor- buildings, with good engineering you can avoid costly surprises, tant item. A structural fire protection plan needs to be prepared get the authorities’ approval in time and help contractors to have early enough in order to get the new arrangement approved by correct materials and drawings for their work. authorities and to enable the contractors to buy correct materials for the work. Ship wide electrical safety systems and HVAC WatMan SWRO S eawater Reverse Osmosis (SWRO) rejects typically 98.5–99.5% of the salinity in one pass. In large-scale production, energy consumption creates a noticeable expense. In conventional SWRO systems, typical energy consumption varies from 6 to 10 kWh/m3-fresh water, depending on salinity, temperature and recovery rate among others. In state-ofthe-art systems with energy recovery the energy consumption can be as low as 2...4 kWh/m3-fresh water. On the other hand, 1-pass SWRO can produce fresh water with about 100 mg/l of chloride at its best. These high rejection systems always need an average feed pressure of 55–70 bars. So called 2-pass SWRO can remove even up to 99.9 % of the total salinity, meaning less than 20 mg/l of chloride, without significantly increasing the energy consumption. These high rejections are often required to achieve high potable water quality. WatMan SWRO Systems can help you to produce extremely low-salinity fresh water with very low energy consumption. This means less energy, less maintenance, less down-time, less costs and more customer satisfac [ۋ