Fighting ecological invaders efficiently

May 11, 2012

Siemens is using a special water-treatment technique to make ship traffic more environmentally friendly. By disinfecting the ballast water in ships, a system named Sicure protects marine environments from damage due to the introduction of alien plant and animal species. In addition, Sicure can also process cooling water. This combination of features is unique worldwide. Siemens has now received full certification for Sicure from the International Maritime Organization (IMO). A new IMO guideline will require that all ocean-going ships be equipped with certified disinfecting equipment for sterilizing their ballast water. This regulation will mean that over 50,000 ships worldwide will have to be retrofitted in the near future.

Ships that aren't carrying a load are stabilized by taking on directly from the sea. However, when discharging that water again, ships can introduce organisms into foreign ecosystems. For example, it was ballast water that introduced the European zebra mussel into the Great Lakes of North America where they have caused extensive damage to and drainage systems. Another example of the phenomenon is provided by the mitten crab, a species from northern Asia, which was brought to North America and Europe where it has caused the extinction of a number of local species. In order to limit natural and , the IMO now requires ships to be equipped with a certified ballast water processing system that conforms to specified standards. Actually, these systems aren't in use 95 percent of the time, because the process of taking on or releasing ballast water doesn't last very long. 

In contrast, because of its ability to process both ballast water and cooling water, the new Sicure system can be in operation continuously, making a separate system for the cooling water unnecessary. The IMO has confirmed Sicure's positive environmental credentials as well as its compliance with safety standards. Sicure is a further development of the Chloropac system, which has successfully been processing seawater in cooling circulation systems for 35 years. The process of electrolysis produces hypochlorite, a disinfectant, from the salt contained in seawater. The system is a combination of a filtering phase followed by an electrolysis phase, where the introduction of the hypochlorite is precisely regulated. Additionally, by injecting a small amount of hypochlorite solution into the water before it enters the ballast water filter, the Sicure system reduces the risk of fouling through biological contaminants. This added step, which reduces system failures and maintenance, has been registered as a patent by Siemens.

Explore further: Sweeping air devices for greener planes

add to favorites email to friend print save as pdf

Related Stories

Coasts' best protection from bioinvaders falling short

Nov 04, 2011

Invasive species have hitchhiked to the U.S. on cargo ships for centuries, but the method U.S. regulators most rely on to keep them out is not equally effective across coasts. Ecologists from the Smithsonian Environmental ...

Satellite data reduce invasion of alien species

Dec 20, 2010

(PhysOrg.com) -- Every day, thousands of different organisms are carried far from their natural habitat in water used as ship ballast. To reduce the transfer of invasive aquatic species between ecosystems, ...

Great Lakes invasive species studied

May 23, 2006

The longstanding problem of various invasive species entering the Great Lakes via the St. Lawrence Seaway is now gaining attention from scientists.

Microbial stowaways: Are ships spreading disease?

May 29, 2008

Ships are inadvertently carrying trillions of stowaways in the water held in their ballast tanks. When the water is pumped out, invasive species could be released into new environments. Disease-causing microbes could also ...

Scientists block ship-borne bioinvaders before they dock

Mar 28, 2011

The global economy depends on marine transportation. But in addition to cargo, the world's 50,000-plus commercial ships carry tiny stowaways that can cause huge problems for the environment and economy. A ...

Recommended for you

Sweeping air devices for greener planes

10 hours ago

The large amount of jet fuel required to fly an airplane from point A to point B can have negative impacts on the environment and—as higher fuel costs contribute to rising ticket prices—a traveler's wallet. ...

User comments : 0