1 INTRODUCTION
1.1 Regulation 13.5 of MARPOL Annex VI requires marine diesel
engines to meet the Tier III NOX emission levels when operating in a
NOX Tier III emission control area in accordance with the provisions
in regulations 13.5.1 and 13.5.2.
1.2 One method for reducing NOX emissions is to use Exhaust Gas
Recirculation (EGR), which is an internal engine process resulting in a
NOX reduction which will meet the requirements of the regulation. By
means of this process, condensate of exhaust gas will be generated and discharged as
bleed-off water, which should be handled differently depending on the fuel oil
sulphur content. EGR may also be used as a Tier II compliance option.
1.3 These Guidelines cover the discharge of EGR bleed-off water. They are
recommendatory in nature; however, the Administrations are invited to base their
implementation on these Guidelines.
2 GENERAL
2.1 Purpose
The purpose of these Guidelines is to specify requirements for the discharge to the
sea of bleed-off water when using EGR.
2.2 Application
These Guidelines should apply to a marine diesel engine fitted with an EGR device
having a bleed-off water discharge arrangement, for which the EIAPP Certificate is
first issued on or after 1 June 2019. It should be noted that any discharge of oil
or oily mixtures into polar waters is prohibited by the Polar Code (see also paragraphs 3.1 and 3.2 of these Guidelines).
2.3 Definitions
2.3.1 "Bleed-off water" means water to be discharged directly, or via a holding tank,
to the sea from an EGR water treatment system.
2.3.2 "EGC" means exhaust gas cleaning.
2.3.3 "EGCS Guidelines" means the 2015 Guidelines for exhaust gas cleaning
systems (resolution MEPC.259(68), as may be amended).
2.3.4 "EGR record book" means a record of the maintenance and servicing of the
monitoring equipment required by these Guidelines. This may be met by following the
relevant requirements of the EGCS Guidelines. This record would include the date,
time, location and quantity of residues delivered ashore from the EGR water
treatment system or may be recorded in the EGCS Record Book.
2.3.5 "Manual for EGR bleed-off discharge system" means the manual containing the
system description, discharge limits and the relevant items required for Onboard
Monitoring Manual (OMM) in the EGCS Guidelines or the Revised Guidelines.
2.4 Required documents
The EGR record book and manual for EGR bleed-off discharge system should be approved
by the Administration. The following documents should be retained on board the ship
as appropriate and should be available for surveys as required:
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.1 manual for EGR bleed-off discharge system;
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.2 certificates for type approval of oil content meters (15 ppm alarm);
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.3 operating and maintenance manuals of oil content meters (15 ppm alarm);
and
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.4 EGR record book.
3 DISCHARGE OF EGR BLEED-OFF WATER INTO THE SEA
3.1 Bleed-off water when using fuel oil not complying with the relevant limit
value in regulation 14 of MARPOL Annex VI
3.1.1 The bleed-off water discharged to the sea from an EGR water treatment system
may or may not be combined with the discharge water from an EGC system. In either
case, this discharge to the sea should be documented, monitored and recorded, as
appropriate, in accordance with the relevant requirements of the EGCS Guidelines.
Upon request, the Administration should be provided with bleed-off water samples
according to appendix 3 of the EGCS Guidelines, as applicable.
3.1.2 Bleed-off water which is retained onboard in a holding tank should not be
discharged to the sea, except when:
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.1 the ship is en route1 and outside polar waters,2 ports, harbours or
estuaries; and
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.2 the bleed-off water discharged meets the provisions of paragraph
3.1.1.
3.2 Bleed-off water when using fuel oil complying with the relevant limit value in
regulation 14 of MARPOL Annex VI
3.2.1 In case the EGR system is in operation and the sulphur content of the fuel oil
used for the engine complies with regulation
14 of MARPOL Annex VI, the discharge of bleed-off water should meet the
requirements of paragraph 3.1, unless the following conditions are satisfied:
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.1 the ship is en routefootnote outside polar waters,footnote ports, harbours or estuaries;
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.2 the sulphur content of the fuel oil used for the engine when the EGR
system is in operation complies with the relevant requirements of regulation 14 of MARPOL Annex VI;
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.3 the oil content meter is type approved in accordance with the annex of
resolution MEPC.107(49), as amended;
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.4 the oil content of the bleed-off water discharge and 15 ppm alarm is
continuously monitored and recorded; and
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.5 the oil content of the discharge does not exceed 15 ppm.
3.2.2 When the EGR system is operated in polar waters,footnote ports, harbours or estuaries, the discharge of
bleed-off water to the sea should comply with section 3.1.
3.2.3 Bleed-off water which is retained on board in a holding tank should not be
discharged to the sea, except when:
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.1 the ship is en routefootnote and outside polar waters,footnote ports, harbours or estuaries; and
-
.2 the bleed-off water discharged meets the provisions of paragraph
3.2.1.
4 RESIDUES FROM EGR WATER TREATMENT SYSTEMS
4.1 Residues from EGR water treatment systems should be delivered ashore to adequate
reception facilities. Such residues should not be discharged to the sea or
incinerated on board.
4.2 Each ship fitted with an EGR unit should record the storage and disposal of
bleed-off water residues in an EGR record book, including the date, time and
location of such storage and disposal.
5 BLEED-OFF WATER ADDITIVES
5.1 In case additives are used for enhancing the bleed-off water quality, an
assessment of the additive should be performed and documented unless the below
substances are used and documented with a Material Safety Data Sheet:
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.1 neutralization agent (caustic substance), such as Sodium Hydroxide (NaOH)
or Sodium Carbonate (Na2CO3); and
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.2 flocculants, which are used for marine approved oily-water separating
equipment.
5.2 For those technologies which make use of chemicals, additives, preparations or
create relevant chemicals, not including those in paragraph 5.1, in situ, there
should be an assessment of the bleed-off water additives. The assessment could take
into account relevant guidelines such as the Procedure for approval of ballast
water management systems that make use of active substances (G9) (resolution MEPC.169(57)), and, if necessary, additional bleed-off water
discharge criteria should be established.
6 SURVEY AND CERTIFICATION
The bleed-off discharge system and the EGR record book should be subject to survey on
installation and at initial, annual/intermediate and renewal surveys by the
Administration. The bleed-off discharge system and the EGR record book may also be
subject to inspection by port State control.