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Environmental Monitoring


January 2016 Issue

Model to Predict
Arctic Winter Sea Ice

Climate scientists at the National Center for Atmospheric Research (NCAR) present evidence in a new study that they can predict whether the Arctic sea ice that forms in the winter will grow, shrink or hold its own over the next several years.

The scientists found that changes in the North Atlantic ocean circulation could allow overall winter sea ice extent to remain steady in the near future, with continued loss in some regions balanced by possible growth in others, including in the Barents Sea.

This type of decadal prediction provides information over a timeframe useful for policy makers and regional stakeholders.

I-Design Scrubber
Enhances PureSOx

The Alfa Laval PureSOx exhaust gas cleaning system is a flexible choice for SOx abatement with compact construction and multiple configurations. With the launch of an inline I-design scrubber, the PureSOx platform is now even more versatile.

An important consideration in creating an inline PureSOx scrubber was the water trap. Because the absorber section is located atop the jet section in the I-design, no water trap is created between the two. A key focus was eliminating the potential for water backflow, which is done by means of an internal water trap combined with overboard arrangements.

The I-design scrubber can be configured with multiple inlets, so one scrubber can handle exhaust gas from multiple sources, including boilers and the main and auxiliary engines.

Another alternative for inline PureSOx configurations is reflux, with two separate loops: one for the jet and a second for the absorber. In the jet loop, clean water is evaporated by means of the waste heat in the exhaust gas, then recondensed as clean water in the absorber loop. As a result, the water in the absorber stage is significantly cleaner.

The water cleaning unit is a vital component of PureSOx. When the scrubber is in closed-loop mode, the unit removes soot from the circulation water, thus protecting the scrubber and enabling compliant discharge of bleed-off.

Environmental Award

COMPAC, Thordon Bearings’ seawater-lubricated propeller shaft bearing system, won the Tanker Shipping & Trade Environment Award for enabling ship owners to cost-effectively comply with stringent marine pollution rules.

COMPAC prevents the seepage of millions of liters of oil into the world’s oceans and reduces ship operating costs associated with aft seals and lubricating oil. Risk of costly emergency aft seal repairs is eliminated, and there are lower maintenance and operational costs.

NPS Report on US
Climate Actions

The National Park Service (NPS) released a report detailing actions underway to address climate change threats to infrastructure, recreation, and natural and cultural resources. This follows a study that revealed sea level rise caused by climate change could pose a risk to more than $40 billion worth of national park assets and resources.

U.S. Secretary of the Interior Sally Jewell highlighted the report during a meeting in Paris with representatives from the UNESCO World Heritage Committee, where the delegates discussed shared challenges in protecting World Heritage sites in the face of a changing climate. Jewell was in Paris for the 21st Conference of Parties (COP21) of the United Nations Framework Convention on Climate Change Conference.

“What’s happening in our national parks is a small window into the impacts of climate change on natural and cultural resources around the world,” Jewell said. “This report offers positive examples of what we can do, at a local level, to adapt and build resilience in the face of a changing climate—even as we work to curb carbon pollution around the world.”

There are 23 U.S. World Heritage sites.

Ballast Water Rules
Confusing, ICS Says

The IMO Ballast Water Management Convention will enter into force worldwide November 24, 2016. ICS believes IMO should finalize the revision of the G8 Type Approval Guidelines as soon as possible to ensure that ship owners can have absolute confidence that the expensive equipment they will soon have to install will be effective in treating ballast water conditions worldwide and be regarded as fully compliant during Port State Control inspections.

The fixing of a definite implementation date gives ship owners some of the certainty needed to make important decisions about whether to refit the new mandatory treatment equipment or start sending ships for early recycling.

However, the entry into force of the new IMO regime does not resolve the difficulties that exist in the U.S., ICS argues. There is still great uncertainty regarding the more stringent U.S. approval regime for treatment equipment, which started to be enforced January 2014 (the U.S. not being a party to the IMO Convention).

The U.S. regulations require all ships that discharge ballast water in U.S. waters to use a treatment system approved by the Coast Guard (USCG). No systems have yet been approved, and ships have been granted deadline extensions for fitting the required treatment systems or permitted to install a USCG-accepted Alternate Management System type-approved in accordance with IMO Guidelines.

Mobil Marine Lubricants
Approved, Endorsed

Thruster builders, including Nakashima, HHI Hyundai and KTE Nakashima Korea, have endorsed use of the Mobil SHC Aware Gear Series, a range of high-performance Environmentally Acceptable Lubricants (EAL), following approvals by seal manufacturers Kemel, BVI and Hwaseung R&A.

The series offers excellent wear protection and safeguards equipment from rust and corrosion. It possesses outstanding oxidation properties, which help to extend oil life, and offers a wide operating temperature range and excellent low-temperature start-up. The lubricants comply with the U.S. Vessel General Permit (VGP). They protect from cavitation, and their seal compatibility helps to minimize leaks.


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