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The outcome of the PPR meeting in February 2020

It’s been about a month since the PPR (Pollution Prevention and Response) meeting in London. What, then, is the verdict from a scrubber manufacturer perspective? Or are you more interested in what impact the agreed outcome will have on shipowners? Regardless of the question, the answer is more or less the same. But before we dig into the specifics, let’s divide the answer into two tracks, just as IMO does: first the EGCS (exhaust gas cleaning system) Guidelines, then EGCS discharges.

The EGCS Guidelines

The draft guidelines were accepted as proposed. However, there were a few previously unsettled issues that the PPR Sub-Committee needed to agree upon. I will touch on a few of these soon, but first, some general remarks.

It is very positive that the draft text relating to how an EGCS should be approved remained as proposed. This means that the approval procedure is more evident, both from a manufacturer and a class society point of view. To date, the approval process has led to many discussions with each and every class society, which has unfortunately delayed approvals on some occasions. This major obstacle has now been removed.

Additionally, MEPC.1/Circ.883 (scrubber malfunction and breakdown) remains as it is and was not incorporated into the EGCS Guidelines. This is good for a number of reasons, but above all because it allowed the new version of the EGCS Guidelines to be finalized. If there are no objections to the current proposal issued by the PPR Sub-Committee, the Guidelines will enter into force six months after the next MEPC meeting.

Now back to some of the open points that the PPR Sub-Committee agreed upon during the meeting. Nitrate sampling is still mandatory (SOx scrubber systems do not pick up NOx since the physical capabilities to do so are not present), but if a manufacturer has analytical results from similar systems, these can be used for the new system. This means that the result of the nitrate sampling no longer halts the IAPP Certification.

The definition of continuous monitoring of discharge water has changed from every 4.85 minutes to every 1.5 minutes. This is positive in the sense that it gives the scrubber business a solid enforcement mechanism. In essence, it will be possible at all times to provide evidence that the quality of the discharge water was indeed within limits. So, no more pointing fingers here.

PAH (polycyclic aromatic hydrocarbon) is still an outstanding issue with regard to technical aspects, but we are getting closer. A few stakeholders have difficulties comprehending the phenanthrene equivalence concept and its usage as a proxy for oil. At this session, a definition of the measurement methodology was agreed upon. However, the PPR Sub- Committee might need to return to this point after completion of the discharge water impact assessment, which I will describe below.

EGCS discharges

IMO is assessing the impact of EGCS discharge water on the marine environment. The aim is, of course, to verify that the current discharge limits stated in the EGCS Guidelines are appropriate. However, it is also an exercise in developing a methodology for how to do an impact assessment, which will be useful if a nation wants to set more stringent criteria in its territorial sea area.

Alfa Laval endorses this work since it means that we as an industry can get rid of any misconceptions and become wiser about the impacts on the marine environment (modelled or analytical). However, the endorsement does come with a certain amount of apprehension, because we see how the discussions relating to the IMO Ballast Water Convention have been prolonged when it comes to assessing impacts on living organisms. Some will argue that there is a significant difference, which there is – but to quote Aristotle: “The more you know, the more you realize you don’t know.”