IN 999 – IMO Cargo Blending Ban - Further Details: Member Feedback Invited

[This note was originally issued as IMCA SEL 05/10 and M 06/10.]

IMCA SEL 25/09 and IMCA M 28/09 invited feedback from members to help decide whether IMCA should take action regarding a recent International Maritime Organization (IMO) circular banning cargo blending during the sea voyage, which it appeared could have implications for vessels involved in well stimulation work. It is important to note that this could also have consequences for support vessels using chemical products, such as muds and brines.

It is clear from our research that, although the IMO circular could be open to interpretation, the blending ban was not intended to apply to the offshore industry. It was therefore decided that IMCA would not make a submission to IMO at this stage, but the secretariat will be monitoring any further discussions on this issue at the IMO sub-committee on bulk liquids and gases (BLG), which is meeting next week.

We would therefore welcome any further information members might have about the types and quantities of oil or chemical products being blended on board offshore support vessels, why certain products may need to be blended en route, and how the blending is carried out.

For those interested in this issue, the background to the IMO ban and the thinking behind the proposed IMCA approach are explained in more detail below.

The IMO circular was in response to possible environmental and safety concerns about the blending at sea of biodiesel cargoes on tankers, but the wording of the circular implies a ban on the blending during the sea voyage of all liquid cargoes regulated by the International Convention for the Prevention of Pollution from Ships (MARPOL). This would include not only oil, which is regulated under MARPOL Annex I, but also chemical products, which fall under MARPOL Annex II. This is no doubt because IMO is still trying to decide whether biofuels and biofuel blends should be regulated as MARPOL Annex I or MARPOL Annex II products, but there are concerns that the IMO circular could be interpreted as preventing well stimulation vessels from carrying out blending for well operations, and might also have implications for other offshore support vessels carrying MARPOL Annex II products, such as drilling fluids.

While this does not apply to chemical processing, the circular prohibits blending operations that use the ship’s cargo pumps and pipelines to internally circulate two or more different cargoes within the ship to achieve a cargo with a different product designation.

The type of routine blending operations being carried out in the offshore industry clearly do not pose the same stability or pollution risks as a tanker creating a new product designation which it may not be properly equipped to handle. It is our understanding that most onboard blending for well operations uses dedicated mixing units and is carried out while the vessel is on station or even connected to the wellhead, when it might even be counted as an installation in certain locations.

On the other hand, it appears that for operational reasons some products may have to be blended en route, and in some jurisdictions even operations carried out alongside could be interpreted as taking place during the sea voyage. It is also not clear to the secretariat to what extent other types of offshore support vessels are engaged in onboard blending, and whether these make use of the ship’s own cargo pumps and pipelines.

So there could be a small chance that the IMO ban could be misinterpreted as applying to offshore operations. However, this seems very unlikely to happen in the main production regions and there is also no indication at present that the IMO circular is actually being enforced. It is clear that the ban was not intended to apply to the offshore industry and trying to obtain an explicit exemption for offshore vessels might raise more questions or just create further confusion, especially if some vessels or operations are excluded and others are not.

On balance, it has therefore been decided not to initiate any request for an exemption at this stage, but to monitor the discussions and ensure that if IMO develops any subsequent blending regulations the wording makes clear that they relate only to biofuel blending on tankers. It is understood that other sectors of the shipping industry have similar concerns and appear to be taking the same approach. In the meantime, the secretariat will continue to try to build up a clearer picture of the type of onboard blending operations that may be taking place on offshore vessels, in case we need to remind IMO why the blending ban was not intended to apply to offshore operations.