What you need to know
The Ballast Water Management Convention could be in force as early as 2012. If you have existing ships, you should be planning for retrofitting a ballast water treatment system (BWTS) now. The good news is that there are a number already available. But how do you decide which one is right for you? Here are our top ten things to consider when selecting a BWTS.
Step 1:Is it approved?
To install a BWTS on board your ship,it must be ‘type approved’ by the flag administration or a Recognised Organisation in accordance with the relevant IMO Guidelines*. If the system uses an active substance, this will need to have received final approval fromthe IMO before type approval canbe granted.
Step 2:Does it have enough capacity?
All BWTS have a ‘total capacity rate’ (TCR). This indicates how many cubic metres of ballast water the system can process each hour. You will need to choose a system with a TCR high enough to handle your ship’s ballast capacity and operational pumping rate.
Step 3:Is it gas safe?
If your ship is a tanker, and the system is going to be installed in a ‘gas dangerous area’ (i.e., in the cargo area), your system must be certified ‘gas safe’.
Step 4:How much space does it need?
System footprints range from approximately 0.25 m2 to 145 m2, depending on their TCR. Some are single units while others can be installed as separate components. This may be useful if you do not have a single space on board ship which is big enough or if access for bringing a single system on board is difficult.
Step 5: What are the capital and operating costs?
A BWTS is a big investment and could cost as much as $2,000,000 depending on the manufacturer. As for operating cost, it depends on the type of system and starts from as little as a few dollars per 1,000 m3 of treated water. Many system suppliers quote operating costs below $20 per 1,000 m3.
Step 6: Do you have enough power available to run the system?
Some systems have very high power requirements – as much as 220kW per 1,000 m3 of treated water. You should check whether you will need to run another generator when the system is in operation or even install an additional generator set. Another consideration is whether you have a spare breaker available in the electrical distribution board to provide power to the BWTS. If not, you will need to find an alternative solution.
Step 7:Will it integrate with your existing systems?
It is advantageous to integrate the alarms and controls for the treatment system with those for the ballast pumping system, so that both can be operated from all control panels.
Step 8:Are consumables, spares and servicing support readily available?
It is important to be able to keep your BWTS operational. If it stops working, you will be in contravention of the Convention and could face fines or detention. Check that spares, consumables and servicing are readily available in all the areas where your ship is trading.
Step 9:What are the implications for crew training?
Whatever BWTS you’re considering, training will be required on operating and maintaining the system, and health and safety aspects such as chemical handling. Training requirements will need to be included in the ballast water management plan required by the Convention.
Step 10:How might it affect tank structure and coatings?
Corrosion and coating degeneration are two potential effects that system substances and processes may have on tanks. You should get assurance from the system manufacturer that tanks will not be adversely affected.
This article is an extract from Lloyd’s ”Shipping And The Environment” issue 02/Spring 2011