Revised IMO guidelines for the approval and certification of exhaust gas cleaning systems, or scrubbers, are due for adoption at the next meeting of the Marine Environment Protection Committee (MEPC 75).
Regulation 4 of MARPOL Annex VI on “Equivalents” allows for the use of alternative compliance methods if they provide at least the same reduction in sulphur oxide emissions as using compliant fuels (maximum 0.10% sulphur content in emission control areas and maximum 0.50% outside ECAs). The EGCS Guidelines specify the criteria for the testing, survey, certification and verification of EGCS to ensure they meet the emission equivalence requirement, while also meeting discharge water quality criteria.
They also cover continuous monitoring requirements for emissions to air and for discharge water quality. Discharge water criteria include minimum pH, maximum PAHs (Polycyclic Aromatic Hydrocarbons) concentration; provisions to minimise suspended particulate matter, including heavy metals and ash, and to prevent discharge of nitrates beyond specified levels.
The draft 2020 EGCS Guidelines, updating the 2015 EGCS Guidelines, were finalised at the Sub-Committee on Pollution Prevention and Response (PPR 7) in February. In general, requirements to ensure scrubbers perform in line with limits on emissions to air and discharges to water have been made more stringent.
It is expected that MEPC 75 will adopt them in early April and require the revised guidelines to be applied to new exhaust gas cleaning systems installed after a date to be decided by the Committee. That could be as soon as the date of adoption plus six months. If so, the revised guidelines would apply when approving systems installed from early October this year onwards. Existing systems approved under the 2015 EGCS Guidelines would not need to be approved again, meaning these should not be affected by changes to requirements around installation of the EGCS and its associated monitoring equipment.
The Guidelines also provide for discharge water data collection. In this regard, it was agreed that Administrations will be invited to apply these when sampling washwater from EGCS that have been approved in accordance with the earlier versions of the EGCS Guidelines. The guidelines also note that discharge water quality criteria should be reviewed in the future as more data becomes available.
The draft 2020 EGCS Guidelines do not include an annex in the 2015 version regarding how to deal with a temporary failure of a single monitoring instrument and recommended actions, as this was dealt with in MEPC.1/Circ.883, issued by MEPC 74 last year.