RESOLUTION MEPC.340(77)
(adopted on 26 November 2021)
2021 GUIDELINES FOR EXHAUST GAS CLEANING SYSTEMS
THE MARINE ENVIRONMENT PROTECTION COMMITTEE,
RECALLING Article 38(a) of the Convention on the International
Maritime Organization concerning the functions of the Marine Environment
Protection Committee (the Committee) conferred upon it by international
conventions for the prevention and control of marine pollution from ships,
RECALLING ALSO that, at its fifty-eighth session, the Committee
adopted, by resolution MEPC.176(58),
a revised MARPOL Annex VI which significantly strengthens the emission limits
for sulphur oxides (SOX),
NOTING that regulation 4 of MARPOL Annex VI allows the use of an
alternative compliance method at least as effective in terms of emission
reductions as that required by the Annex, including any of the standards set
forth in regulation 14, taking into account guidelines developed by the
Organization,
RECALLING that, at its fifty-ninth session, the Committee adopted,
by resolution MEPC.184(59),
the 2009 Guidelines for exhaust gas cleaning systems,
RECALLING ALSO that, at its sixty-eighth session, the Committee
adopted, by resolution MEPC.259(68),
the 2015 Guidelines for exhaust gas cleaning systems (hereinafter
referred to as the "2015 EGCS Guidelines"),
RECOGNIZING the need to update the 2015 EGCS Guidelines,
HAVING CONSIDERED, at its seventy-seventh session, draft amendments
to the 2015 EGCS Guidelines, prepared by the Sub-Committee on Pollution
Prevention and Response at its seventh session,
1 ADOPTS the 2021
Guidelines for exhaust gas cleaning systems (hereinafter referred to as the
"2021 EGCS Guidelines"), as set out in the annex to the present
resolution;
2 INVITES
Administrations to implement the 2021 EGCS Guidelines and apply them to exhaust
gas cleaning systems installed on ships the keels of which are laid or which
are at a similar stage of construction on or after 1 June 2022; or exhaust gas
cleaning systems installed on ships the keels of which are laid or which are at
a similar stage of construction before 1 June 2022 which have a contractual
delivery date of EGCS to the ship on or after 1 June 2022 or, in the absence of
a contractual delivery date, the actual delivery of the exhaust gas cleaning
system to the ship on or after 1 June 2022; or amendments, as those specified
in paragraphs 4.2.2.4 or 5.6.3 of the 2021 EGCS Guidelines, to existing exhaust
gas cleaning systems undertaken on or after 1 June 2022, when allowing the use
of an exhaust gas cleaning system in accordance with regulation 4 of MARPOL
Annex VI;
3 REQUESTS Parties
to MARPOL Annex VI and other Member Governments to bring the 2021 EGCS
Guidelines to the attention of shipowners, ship operators, shipbuilders, marine
diesel engine manufacturers and any other interested groups;
4 INVITES
Administrations to provide for discharge water data collection as described in
appendix 3 of these Guidelines, and to also apply that appendix when
undertaking related sampling from exhaust gas cleaning systems that have been
approved in accordance with the earlier versions of the EGCS Guidelines;
5 AGREES to keep
these Guidelines under review in the light of experience gained with their
application; and
6 ALSO AGREES that
these Guidelines supersede the 2015 EGCS Guidelines adopted by resolution MEPC.259(68).
ANNEX
2021 GUIDELINES FOR EXHAUST GAS CLEANING SYSTEMS
1 INTRODUCTION
1.1 MARPOL Annex VI
requires ships to use fuel oil with a sulphur content not exceeding that
stipulated in regulations 14.1 or 14.4. Regulation 4 allows, with the approval
of the Administration, the use of an alternative compliance method at least as
effective in terms of emission reductions as that required by the Annex,
including the standards set forth in regulation 14. The Administration of a
Party should take into account any relevant Guidelines developed by the
Organization pertaining to alternatives provided for in regulation 4.
1.2 These Guidelines
have been developed to allow for the testing, survey, certification, and
approval of Exhaust Gas Cleaning Systems (EGCSs) in accordance with regulation
4 of MARPOL Annex VI.
1.3 Equivalency with
the relevant requirements of regulation 14 of MARPOL Annex VI should be
demonstrated by using these Guidelines as a basis of compliance with the
relevant Emission Ratio limit value as given in table 1. Where the design or
operation of an EGCS requires controls in addition to those given in these
Guidelines in order to meet the requirements of regulation 4.4 of the
above-mentioned Annex, they should be subject to special consideration by the
Administration and should be communicated to the Organization when submitting
the notification required by regulation 4.2 of MARPOL Annex VI.
Table 1: Fuel oil sulphur limits in regulations 14.1 and 14.4 and
corresponding Emission Ratio limit values
Fuel oil sulphur content (% m/m) |
Emission Ratio SO2(ppm)/CO2(% v/v) |
0.50 |
21.7 |
0.10 |
4.3 |
Note: The use of the above Emission Ratio limit values is only
applicable when using petroleum-derived distillate or residual fuel oils. See
appendix 2 for the assumptions and rationale which form the basis of the
Emission Ratio method.
1.4 These Guidelines
are recommendatory in nature; however, Administrations are invited to base the
implementation of the relevant requirements of regulation 4 of MARPOL Annex VI
on them.
2 GENERAL
2.1 Purpose
2.1.1 The purpose of these
Guidelines is to specify the criteria for the testing, survey, certification
and verification of EGCSs under regulation 4 of MARPOL Annex VI to ensure that
they provide in service, at any operating load point at which they are to
operate, including during transient operation, effective equivalence to the
requirements of regulations 14.1 or 14.4 of MARPOL Annex VI, as applicable.
2.1.2 These Guidelines
describe two schemes for approval of an EGCS: Scheme A (system certification
with in-service continuous operational parameter monitoring and periodic
emission checks) and Scheme B (continuous emission monitoring by means of an
approved monitoring system together with periodic operational parameter
checks):
.1 in Scheme A, the
EGCS is subject to approval by the Administration and should be as given in
section 4 subject to performance tests, sea trials or other similar physical
tests that verify that the system in service will result in the intended
performance; and
.2 in Scheme B, the
exhaust gas monitoring system of the EGCS is subject to approval by the
Administration and should be as given in section 5. Approved exhaust gas
monitoring system should continuously indicate the Emission Ratio while the
EGCS is in operation, allowing verification against the applicable limit.
2.1.3 Emission testing in
relation to either Scheme A or Scheme B should be undertaken, as appropriate,
as given in section 6.
2.1.4 Data recording,
retention and the preparation of reports using that data in relation to either
Scheme A or Scheme B should be, as appropriate, as given in section 7.
2.1.5 Details of the
monitoring systems for exhaust emissions, operating parameters, inlet water,
washwater and discharge water in relation to either Scheme A or Scheme B should
be documented, as appropriate, as given in section 8.
2.1.6 For ships which are
to use an EGCS in part or in total as an approved equivalent to the
requirements of regulations 14.1 and/or 14.4 of MARPOL Annex VI, there should be
an approved SOX Emissions Compliance Plan (SECP) as given in section
9.
2.1.7 Discharge water
monitoring which is equally applicable to Scheme A and Scheme B should be
undertaken as given in section 10.
2.2 Application
2.2.1 These Guidelines apply
to any EGCS as applied to fuel oil combustion unit(s), excluding shipboard
incinerators, installed on board a ship.
2.2.2 For the purpose of
these Guidelines, the term "EGCS" should be generally, but not
exclusively (see 2.2.3), understood as "wet EGCS".
2.2.3 In the absence of
specific guidelines for EGCSs which use technologies or operate in modes that
are not defined in 2.3, these Guidelines may also be applied as appropriate.
2.2.4 These Guidelines
apply to:
.1 EGCSs installed on ships
the keels of which are laid or which are at a similar stage of construction on
or after 1 June 2022; or
.2 EGCSs installed on
ships the keels of which are laid or which are at a similar stage of
construction before 1 June 2022 which have a contractual delivery date of EGCS
to the ship on or after 1 June 2022 or, in the absence of a contractual
delivery date, the actual delivery of the EGCS to the ship on or after 1 June
2022; or
.3 amendments as those
specified in 4.2.2.4 or 5.6.3 to existing EGCSs undertaken on or after 1 June
2022.
2.3 Abbreviations,
definitions and required documents
2.3.1 Abbreviations as
given in table 2 and definitions as given in table 3 are applied in these
Guidelines.
Table 2: Abbreviations
CL |
Closed-Loop |
CO2 |
Carbon dioxide |
EGC |
Exhaust gas cleaning |
EGCS |
Exhaust gas cleaning system |
ETM-A |
EGCS - Technical Manual for Scheme A |
ETM-B |
EGCS - Technical Manual for Scheme B |
MCR |
Maximum Continuous Rating |
SECP |
SOX Emissions Compliance Plan |
SECC |
SOX Emissions Compliance Certificate |
SO2 |
Sulphur dioxide |
SOX |
Sulphur oxides |
OL |
Open-Loop |
OMM |
Onboard Monitoring Manual |
PAH |
Polycyclic Aromatic Hydrocarbons |
PAHphe |
Polycyclic Aromatic Hydrocarbons as phenanthrene equivalents
(see table 3) |
UTC |
Universal Time Coordinated |
Table 3: Definitions
12-hour period |
A period of 12 consecutive hours determined on a rolling basis
with new 12-hour periods beginning past each hour of EGCS operation. |
Bleed-off water |
An amount of aqueous solution removed from the washwater of an
EGCS operating in closed-loop mode to keep its required operating properties
and efficiency. |
Certified Value |
The Emission Ratio specified by the manufacturer that the EGCS
is certified as meeting when operating on a continuous basis on the
manufacturer-specified maximum fuel sulphur content and within the specified
operational parameters. Applicable to Scheme A only. |
Closed-loop mode |
EGCS operating mode in which the washwater is passed several
times through the EGC unit. In order for the washwater to keep its required operating
properties and efficiency, its pH usually has to be adjusted, e.g. by adding
chemicals such as NaOH. In addition, a small amount of washwater is bled,
periodically or continuously, from the system. This bleed-off water, unless
meeting discharge water criteria, needs to be treated to meet discharge water
criteria, or is regarded as EGCS residue. |
Continuous monitoring |
Process and technology used for evaluation of EGCS compliance
through representative measurement, at a specified frequency, for selected
parameters. |
Discharge water |
Any water from an EGCS to be discharged overboard. |
EGC unit |
Device within which exhaust gas and cleaning medium are mixed.
An EGC unit may have a single or multiple fuel oil combustion unit(s)
connected to it. |
EGCS Electronic Data Recording, or Electronic Logging System |
Automatic record of the EGCS in service operating parameters.
The record of parameters does not involve any user input. |
EGCS Record Book (or Electronic Record Book) |
A user-input record of the EGCS, component adjustments,
corrective and planned maintenance and service records as appropriate. It can
have an electronic format. |
EGCS residue |
Material removed from the washwater or the bleed-off water by a
treatment system or discharge water that does not meet the discharge
criterion, or other residue material removed from the EGCS. |
Emission Ratio |
SO2 expressed in ppm/CO2 expressed in %
v/v. |
Exhaust Gas Cleaning System (EGCS) |
A system that includes one or more EGC units and which is based
on technology that uses a wet cleaning medium for the reduction of SOX
from an exhaust gas stream from installed fuel oil combustion unit(s),
operating in either open-loop or closed-loop mode. A hybrid EGCS can operate
in both open-loop mode and closed-loop mode. Several EGC units may utilize a
common uptake system with a single exhaust gas monitoring system. Several EGC
units may utilize a common washwater, water supply, treatment and/or
overboard system and discharge water monitoring equipment. |
Extractive sampling system |
System which extracts a sample flow from the exhaust gas stream
and transfers it by heated lines to the measurement instrument. |
Fuel oil combustion unit |
Any engine, boiler, gas turbine, or other fuel oil fired
equipment, excluding shipboard incinerators. |
Inlet water |
Water entering the ship as a cleaning medium for an EGC unit. |
In situ |
Measuring directly within an exhaust gas stream. |
Load range |
Interval ranging from minimum practicable to maximum rated power
of diesel engine or maximum steaming rate of the boiler. |
Open-loop mode |
EGCS operating mode in which the washwater, typically seawater,
is passed through the EGC unit only once before it is being discharged
overboard as discharge water. |
Phenanthrene equivalent |
It corresponds to the signal produced by a PAH monitor with
excitation wavelengths between 244 nm and 264 nm (254±10 nm) and detection
wavelengths between 310 nm and 410 nm (360±50 nm) calibrated against a known
set of phenanthrene concentrations within the expected measurement range when
exposed to EGCS discharge water containing a range of different PAH species. |
Washwater |
Cleaning medium brought into contact with the exhaust gas stream
for the reduction of SOX. |
Wet EGCS |
EGCS using liquid cleaning medium. |
2.3.2 Relevant documents
for EGCSs approved in accordance with Scheme A and Scheme B are listed in table
4.
Table 4: Relevant documents for Scheme A and Scheme B
Document |
Scheme A |
Scheme B |
SECP |
X |
X |
SECC |
X |
|
ETM Scheme A |
X |
|
ETM Scheme B |
|
X |
OMM |
X |
X |
EGCS Record Book or Electronic Record Book |
X |
X |
3 SAFETY NOTE
3.1 Due attention is to
be given to the safety implications related to the handling and proximity of exhaust
gases, the measurement equipment and the storage and use of pressurized
containers of pure and calibration gases. Sampling positions and permanent
access platforms should be such that this monitoring may be performed safely.
For positioning the EGCS discharge water outlet, due consideration should be
given to the locations of the existing seawater inlets. In all operating
conditions the design of the EGCS should take into consideration the necessary
balance between low pH water discharge and the anti-corrosive resistance of the
surfaces in contact with that discharge stream. To avoid premature failure of
sea chests, discharge pipework and hull penetration finishes, due care should
be taken in the preparation of surfaces and the correct selection and application
of protective coatings to withstand the corrosive effects of low pH discharge
water.
3.2 In cases where
exhaust gas duct bypass lines are arranged on board, appropriate measures
should be taken to prevent leakage of exhaust gases from the damper to bypass
lines.
4 SCHEME A - EGCS
APPROVAL, SURVEY AND CERTIFICATION USING PARAMETER AND EMISSION CHECKS
4.1 Approval of EGCSs
4.1.1 General
Options under Scheme A of these Guidelines provide for:
.1 individual EGCS
approval;
.2 serially
manufactured systems; and
.3 production range
approval.
4.1.2 Individual EGCS
approval
4.1.2.1 An EGCS should be
certified as capable of meeting the Emission Ratio value, the Certified Value,
specified by the manufacturer (e.g. the Emission Ratio value the system is
capable of achieving on a continuous basis) with fuel oils of the
manufacturer's specified maximum % m/m sulphur content and for the range of
operating parameters, as listed in 4.2.2.1.2, for which they are to be approved.
The Certified Value should at least be suitable for ship operations under
requirements given by MARPOL Annex VI regulations 14.1 and/or 14.4.
4.1.2.2 Where testing is
not to be undertaken with fuel oils of the manufacturer's specified maximum %
m/m sulphur content, the use of two test fuels with a lower % m/m sulphur
content is allowed. The two fuels selected should have a difference in % m/m
sulphur content sufficient to demonstrate the operational behaviour of the EGCS
and to demonstrate that the Certified Value can be met if the EGCS were to be
operated with a fuel of the manufacturer's specified maximum % m/m sulphur
content. In such cases a minimum of two tests, in accordance with subsection
4.3 as appropriate, should be performed. These tests need not be sequential and
could be undertaken on two different, but identical, EGCSs.
4.1.2.3 The maximum and, if
applicable, minimum exhaust gas mass flow rate of the system should be stated.
The effect of variation of the other parameters defined in 4.2.2.1.2 should be
justified by the equipment manufacturer. The effect of variations in these
factors should be assessed by testing or otherwise as appropriate. No variation
in these factors, or combination of variations in these factors, should be such
that the emission value of the EGCS would be in excess of the Certified Value.
4.1.2.4 Data obtained in
accordance with this section should be submitted to the Administration for
approval together with the ETM-A.
4.1.3 Serially
manufactured systems
4.1.3.1 In the case of
nominally similar EGCSs of the same mass flow ratings as that certified under
4.1.2, and to avoid the testing of each EGCS, the Administration, based on a
submission of the equipment manufacturer, should take the necessary measures to
verify that adequate arrangements have been made to ensure effective control of
the conformity of production arrangement. The certification of each EGCS under
this arrangement should be subject to such surveys that the Administration
should consider necessary as to assure that each EGCS has an Emission Ratio
value of not more than the Certified Value when operated in accordance with the
parameters defined in 4.2.2.1.2.
4.1.4 Product range
approval
4.1.4.1 In the case of an
EGCS of the same design, but of different maximum exhaust gas mass flow
capacities, the Administration may accept, in lieu of tests on an EGCS of all
capacities in accordance with 4.1.2, tests of EGCSs of three different
capacities provided that the three tests are performed at intervals including
the highest, lowest and one intermediate capacity rating within the range.
4.1.4.2 Where there are
significant differences in the design of EGCSs of different capacities, this
procedure should not be applied unless it can be shown, to the satisfaction of
the Administration, that in practice those differences do not materially alter
the performance between the various EGCS types.
4.1.4.3 For EGCSs of
different capacities, the sensitivity to variations in the type of combustion
machinery to which they are fitted should be detailed together with sensitivity
to the variations in the parameters listed in 4.2.2.1.2. This should be on the
basis of testing, or other data as appropriate.
4.1.4.4 The effect of
changes of EGCS capacity on washwater and discharge water characteristics
should be detailed.
4.1.4.5 All supporting data
obtained in accordance with this section, together with the ETM-A for each
system, should be submitted to the Administration for approval.
4.2 Survey and certification
4.2.1 Procedures for the
certification of an EGCS
4.2.1.1 In order to meet
the criterion of subsection 4.1 either prior to, or after installation on
board, each EGCS should be certified as meeting the Certified Value specified
by the manufacturer (e.g. the Emission Ratio the system is capable of achieving
on a continuous basis) under the operating conditions and restrictions as given
by the EGCS Technical Manual (ETM-A) as approved by the Administration.
4.2.1.2 Determination of
the Certified Value should take into account the provisions of these
Guidelines.
4.2.1.3 Each EGCS meeting
the criterion of 4.2.1.1 should be issued an SECC by the Administration. The
form of the SECC is given in appendix 1.
4.2.1.4 Application for an
SECC should be made by the EGCS manufacturer, shipowner or other party.
4.2.1.5 Any subsequent EGCS
of the same design and rating as that certified under 4.2.1.1 may be issued
with an SECC by the Administration without the need for testing taking into
account 4.2.1.1 subject to 4.1.3 of these Guidelines.
4.2.1.6 EGCSs of the same
design, but with ratings different from that certified under 4.2.1.1 may be
accepted by the Administration subject to 4.1.4 of these Guidelines.
4.2.1.7 EGCSs which treat
only part of the exhaust gas flow of the uptake in which they are fitted should
be subject to special consideration by the Administration to ensure that under
all defined operating conditions the overall Emission Ratio value of the
exhaust gas downstream of the system is no more than the Certified Value.
4.2.2 EGCS Technical
Manual "Scheme A" (ETM-A)
4.2.2.1 Each EGCS should be
supplied with an ETM-A provided by the manufacturer. This ETM-A should, as a
minimum, contain the following information:
.1 the identification of the system
(manufacturer, model/type, serial number and other details as necessary)
including a description of the system and any required ancillary systems. In
case a system contains more than one EGC unit, each EGC unit should be
identified;
.2 the operating limits, or range of
operating values, for which the unit is certified. These should, as a minimum,
include:
.1 the maximum and, if applicable, minimum
mass flow rate of exhaust gas;
.2 the maximum and, if applicable, minimum
exhaust gas mass flow rate capacity of the EGC unit;
.3 the maximum fuel oil sulphur content the
EGCS is certified for;
.4 the Certified Value;
.5 the power, type and other relevant
parameters of the fuel oil combustion unit which the EGCS is to be connected
to; for boilers also the maximum air/fuel ratio at 100% load should be given;
and for diesel engines whether the engine is of 2 or 4-stroke cycle should be
indicated;
.6 the maximum and minimum washwater flow
rate, inlet pressures and minimum inlet water alkalinity (ISO 9963-1-2:1994);
.7 the exhaust gas inlet temperature ranges
and maximum and minimum exhaust gas outlet temperature with the EGCS in
operation;
.8 the maximum exhaust gas differential
pressure across the EGC unit and the maximum exhaust gas inlet pressure;
.9 the salinity levels or fresh water
elements necessary to provide adequate neutralizing agents; and
.10 other factors concerning the design and
operation of the EGCS relevant to achieving a maximum Emission Ratio value no
higher than the Certified Value;
.3 any requirements or restrictions
applicable to the EGCS or associated equipment necessary to enable the system
to achieve a maximum Emission Ratio value no higher than the Certified Value;
.4 maintenance, service or adjustment
requirements in order that the EGCS can continue to achieve a maximum Emission
Ratio value no higher than the Certified Value. The maintenance, servicing and
adjustments should be recorded in the EGCS Record Book;
.5 corrective actions to be applied if the
following occurs or is expected to occur: operating conditions are outside
approved ranges or limits; the discharge water quality criteria are not met; or
exceedances of the Certified Value;
.6 a verification procedure to be used during
surveys to ensure that the system's performance is maintained and that the
system is used as required (see subsection 4.4);
.7 washwater and discharge water
characteristics across the operating load range;
.8 design requirements for the treatment and
monitoring of washwater and control of discharge water, including, for example,
bleed-off water from closed-loop EGCS operation or discharge water temporarily
stored within the EGCS; and
.9 detail the procedure
to produce reports regarding operation in a non-compliant condition, or in a
condition where the ongoing compliance would be temporary indicated in
accordance with 8.2.8.
4.2.2.2 The ETM-A should be
approved by the Administration.
4.2.2.3 The ETM-A should be
retained on board the ship onto which the EGCS is installed and should be
available for surveys as required.
4.2.2.4 Amendments to the
ETM-A which reflect EGCS changes that affect performance with respect to
emissions to air and/or water should be approved by the Administration. Where
additions, deletions or amendments to the ETM-A are separate to the ETM-A as
initially approved, they should be retained with the ETM-A and should be
considered as part of it.
4.2.3 In-service surveys
4.2.3.1 The EGCS should be
subject to survey on installation and at initial, annual/intermediate and
renewals surveys by the Administration.
4.2.3.2 In accordance with
regulation 10 of MARPOL Annex VI, the EGCS may also be subject to inspection by
port State control.
4.2.3.3 Prior to use, each
EGCS should be issued with an SECC by the Administration.
4.2.3.4 Following the
installation survey given in 4.2.3.1, sections 2.3 and 2.6 of the Supplement to
the ship's International Air Pollution Prevention Certificate should be duly
completed.
4.3 Emission limits
4.3.1 Each EGCS should be
capable of reducing emissions to equal to or less than the Certified Value at
any load point, including fuel oil combustion unit idling, when operated in
accordance with 4.2.2.1.2.
4.3.2 In order to
demonstrate performance, emission measurements should be undertaken, with the
agreement of the Administration, at a minimum of four load points. One load
point should be at 95% to 100% of the maximum exhaust gas mass flow rate for
which the unit is to be certified. One load point should be within ± 5% of the
minimum exhaust gas mass flow rate for which the unit is to be certified. The
other two load points should be equally spaced between the maximum and minimum
exhaust gas mass flow rates. Where there are discontinuities in the operation
of the system, the number of load points should be increased, with the
agreement of the Administration, so that it is demonstrated that the required
performance over the stated exhaust gas mass flow rate range is retained.
Additional intermediate load points should be tested if there is evidence of an
emission peak below the maximum exhaust gas mass flow rate and above, if
applicable, the minimum exhaust gas flow rate. These additional tests should be
of sufficient number as to establish the emission peak value.
4.4 Onboard
verification procedures for demonstrating compliance
4.4.1 For each EGCS, the
ETM-A should contain a verification procedure for use during surveys as
required. This procedure should not require specialized equipment or an
in-depth knowledge of the system. Where particular devices are required, they
should be provided and maintained as part of the system. The EGCS should be
designed in such a way as to facilitate inspection as required. The basis of
the verification procedure is that if all relevant components and operating
values or settings are within the approved ranges, then the performance of the
EGCS can be assumed to meet the requirements without the need for actual
continuous exhaust emission monitoring.
4.4.2 Included in the
verification procedure should be all components and operating values or
settings which may affect the operation of the EGCS and its ability to meet the
Certified Value.
4.4.3 The verification
procedure should be provided by the EGCS manufacturer and approved by the
Administration.
4.4.4 The verification
procedure should cover both a documentation check and a physical check of the
EGCS.
4.4.5 The surveyor should
verify that each EGCS is installed in accordance with the ETM-A and has an SECC
as required.
4.4.6 At the discretion of
the Administration, the surveyor should have the option of checking one or all
of the identified components, operating values or settings. Where there is more
than one EGC unit within the EGCS, the Administration may, at its discretion,
abbreviate or reduce the extent of the survey on board; however, the entire
survey should be completed for at least one of each type of EGC unit on board
provided that it is expected that the other EGC units perform in the same
manner.
4.4.7 The EGCS should
include means to automatically record when the system is in use. These means
should automatically record, at least at the frequency specified in 5.4.2, as a
minimum, washwater pressure and flow rate at the EGC unit's inlet connection,
exhaust gas pressure before and pressure drop across each EGC unit, fuel oil
combustion unit load, and exhaust gas temperature before and after the EGC unit
against the respective operating limits, or range of operating values. The data
recording system should comply with the requirements of sections 7 and 8. In
the case of a system consuming chemicals at a known rate as documented in
ETM-A, recordings of such consumption in the EGCS Record Book also serves this
purpose.
4.4.8 Under Scheme A, if a
continuous exhaust gas monitoring system is not fitted, a daily spot check of
the Emission Ratio for a duration of not less than five minutes at a minimum
recording frequency of 0.1 Hz at normal working condition for each outlet to
the atmosphere should be undertaken to verify compliance in conjunction with
the continuous monitoring of the parameters stipulated in 4.4.7. The exhaust
gas readings should be allowed to stabilize before commencing recording.
Readings from the calibration procedure should be automatically recorded or
noted in a calibration protocol. Emission values, which are used to determine
the Emission Ratio, obtained after stabilization should be recorded. If a
continuous exhaust gas monitoring system is fitted, only daily spot checks of
the parameters listed in paragraph 4.4.7 would be needed to verify proper
operation of the EGC unit.
4.4.9 An EGCS Record Book
should be maintained on board the ship recording maintenance and service of the
system including like-for-like replacement. This EGCS Record Book should be
available during surveys as required and may be read in conjunction with
engine-room logbooks and other data, as necessary, to confirm the correct
operation of the EGCS. The form of this record should be provided by the EGCS
manufacturer and approved by the Administration. Alternatively, this
information may be recorded in the ship's planned maintenance record system as
approved by the Administration. Alternatively, this information may be recorded
in an Electronic Record Book as approved by the Administration. The EGCS Record
Book entries should be maintained on board the ship for a minimum period of
three years after the last entry has been made.
5 SCHEME B - EGCS
APPROVAL, SURVEY AND CERTIFICATION USING CONTINUOUS MONITORING OF EMISSION
RATIO
5.1 General
5.1.1 Scheme B provides
for the approval of the means of continuous Emission Ratio monitoring,
supported by daily parameter checks, which will subsequently be used at surveys,
and otherwise as required, to demonstrate compliance with the objectives as
given in the SECP.
5.2 Approval
5.2.1 The ETM-B, as
defined in these Guidelines, should be approved by the Administration.
5.3 Survey and
certification
5.3.1 The EGCS's exhaust
gas monitoring system should be subject to survey on installation and at
initial, annual/intermediate and renewals surveys by the Administration in
order to demonstrate that it functions as given in the OMM. The scope of the
installation or initial survey should include EGCS operation, as required, in
order to demonstrate the functionality of the exhaust gas monitoring system.
5.3.2 Following the
installation survey given in 5.3.1 and approval of documents as listed in
2.3.2, sections 2.3 and 2.6 of the Supplement to the ship's International Air
Pollution Prevention Certificate should be duly completed.
5.4 Exhaust gas
monitoring
5.4.1 The exhaust gas
composition of the Emission Ratio should be measured at an appropriate position
after the EGC unit and that measurement should be as given in section 6 as
applicable. A suitable position could be downstream of the EGC unit, but before
any possible mixing of outside ambient air or other additional air or gases
with the exhaust gas.
5.4.2 SO2(ppm)
and CO2(%) and, to not less than one decimal place, the Emission
Ratio should be continuously monitored and recorded against the applicable
Emission Ratio limit onto a data recording and processing device at a rate
which should not be less than 0.0035 Hz whenever the EGCS is in operation. This
monitoring may be suspended for service and maintenance periods of gas analyser
and associated equipment as required by the OMM. Zero and span check
calibration and instrument drift data should, as given in the OMM, be either
recorded by the data recording system or manually entered in the EGCS Record
Book as appropriate to the means used.
5.4.3 If more than one
analyser is to be used to determine the Emission Ratio, these should have
similar sampling and measurement times and the data outputs aligned to ensure
that the Emission Ratio is fully representative of the exhaust gas composition.
5.5 Onboard
verification procedures for demonstrating compliance with emission limits
5.5.1 The data recording
system should be as given in sections 7 and 8. Data and the associated reports
should be available to the Administration as necessary to demonstrate
compliance as required and, in accordance with regulation 10 of MARPOL Annex
VI, may also be subject to inspection by port State control.
5.5.2 Daily spot checks of
the parameters listed in 4.4.7 are needed to verify proper operation of the
EGCS and should be recorded in the EGCS Record Book or in the engine-room
logger system.
5.6 EGCS Technical
Manual "Scheme B" (ETM-B)
5.6.1 Each EGCS should be
supplied with an ETM-B provided by the manufacturer. This ETM-B should, as a
minimum, contain the following information:
.1 the identification of the system
(manufacturer, model/type, serial number and other details as necessary)
including a description of the system and any required ancillary systems. If a
system consists of more than one EGC unit, each EGC unit should be identified;
.2 the operating limits, or range of
operating values, for which the system is designed. These should, as a minimum,
include:
.1 the maximum and, if applicable, minimum
mass flow rate of exhaust gas;
.2 the advised maximum fuel sulphur content
for the operational conditions the EGCS is designed for (Note: higher sulphur
content fuel oils may be used provided the relevant Emission Ratio value is not
exceeded);
.3 the power, type and other relevant
parameters of the fuel oil combustion unit for which the EGCS is to be
connected to. For boilers, the maximum air/fuel ratio at 100% load should also
be given for diesel engines whether the engine is of 2 or 4-stroke cycle;
.4 the maximum and minimum washwater flow
rate, inlet pressures and minimum inlet water alkalinity (ISO 9963-1-2:1994);
.5 the exhaust gas inlet temperature ranges
and maximum and minimum exhaust gas outlet temperature with the EGCS in
operation;
.6 the maximum exhaust gas differential
pressure across the EGC unit and the maximum exhaust gas inlet pressure;
.7 the salinity levels or fresh water
elements necessary to provide adequate neutralizing agents; and
.8 other parameters as necessary concerning
the operation of the EGCS;
.3 any requirements or restrictions
applicable to the EGCS or associated equipment;
.4 corrective actions to be applied if the
following occurs or is expected to occur: operating conditions are outside
approved ranges or limits; the discharge water quality criteria are not met; or
exceedances of the maximum allowable Emission Ratio;
.5 washwater and discharge water
characteristics across the operating load range;
.6 design requirements for the treatment and
monitoring of washwater and control of discharge water, including for example
bleed-off water from closed-loop EGCS operation or discharge water temporarily
stored within the EGCS; and
.7 detail the procedure
for producing reports regarding operation in a non-compliant condition, or in a
condition where the ongoing compliance would be temporary indicated in
accordance with 8.2.8.
5.6.2 The ETM-B should be
retained on board the ship onto which the EGCS is fitted. The ETM-B should be
available for surveys as required.
5.6.3 Amendments to the
ETM-B which reflect EGCS changes that affect performance with respect to
emissions to air and/or water should be approved by the Administration. Where
additions, deletions or amendments to the ETM-B are separate from the ETM-B as
initially approved, they should be retained with the ETM-B and should be
considered as part of it.
5.7 Onboard procedures
for demonstrating compliance
5.7.1 An EGCS Record Book
should be maintained on board the ship recording maintenance and servicing of
the emission monitoring and ancillary components as given in the OMM including
like-for-like replacements. The form of this record book should be approved by
the Administration. This EGCS Record Book should be available at surveys as
required and may be read in conjunction with engine-room logbooks and other
data as necessary to confirm the correct operation of the EGCS. Alternatively, this
information may be recorded in the ship's planned maintenance record system as
approved by the Administration. Alternatively, this information may be recorded
in an Electronic Record Book as approved by the Administration. The EGCS Record
Book entries should be maintained on board the ship for a minimum period of
three years after the last entry has been made.
6 EMISSION TESTING
6.1 Emission testing
should follow the requirements of the NOX Technical Code 2008 except
as provided for in these Guidelines.
6.2 CO2
should be measured using an analyser operating on the non-dispersive infrared
(NDIR) principle and with additional equipment such as dryers as necessary. SO2
should be measured using analysers operating on NDIR or non-dispersive ultra-violet
(NDUV) principles and with additional equipment such as dryers as necessary.
Other systems or analyser principles may be accepted, subject to the approval
of the Administration, provided they yield equivalent or better results than
those of the equipment referenced above. For acceptance of other CO2
systems or analyser principles, the reference method should be in accordance
with the requirements of appendix III of the NOX Technical Code
2008.
6.3 The analysing
equipment should be installed, operated, maintained, serviced and calibrated in
accordance with the requirements as given in the OMM, at a frequency which
ensures that the requirements of 1.7 to 1.10 of appendix III of the NOX
Technical Code 2008 are met at all times the equipment is in operation.
6.4 An exhaust gas
sample for SO2 should be obtained from a representative sampling
point downstream of the EGC unit.
6.5 SO2 and
CO2 should be monitored using either in situ or extractive sampling
systems.
6.6 Extractive exhaust
gas samples for SO2 determination should be maintained at a
sufficient temperature to avoid condensation of water in the sampling system
and hence loss of SO2.
6.7 If an extractive
exhaust gas sample for determination needs to be dried prior to analysis it should
be done in a manner that does not result in loss of SO2 in the
sample as analysed.
6.8 The SO2
and CO2 values should be compared on the basis of the same residual
water content (e.g. dry or with the same wetness fraction).
6.9 In justified cases
where the CO2 concentration is reduced by the EGC unit, the CO2
concentration can be measured at the EGC unit inlet, provided that the
correctness of such a methodology can be clearly demonstrated. In such cases
the SO2 and CO2 values should be compared on a dry basis.
If measured on a wet basis the water content in the exhaust gas stream at those
points should also be determined in order to correct the readings to dry basis
values. For calculation of the CO2 value on a dry basis, the dry/wet
correction factor may be calculated in accordance with paragraph 5.12.3.2.2 of
the NOX Technical Code 2008.
6.10 Extractive sample
systems should be verified to be free of ingress leakage in accordance with the
analysing equipment manufacturers' recommendations at intervals as defined in
the OMM. It should be verified that the system is free of ingress on initial
start-up and as given in the OMM with the findings from those checks recorded
in the EGCS Record Book.
6.11 The span gases for
the SO2 and CO2 analyser should be a mixture of SO2
and/or CO2 and nitrogen at a concentration of more than 80% of the
full scale of the measuring range used. The span gas for the CO2
should conform to the requirements of section 2 of appendix IV of the NOX Technical
Code 2008. Other equivalent arrangements, as detailed in the OMM, may be
accepted by the Administration.
7 DATA RECORDING AND
PROCESSING DEVICE
7.1 The recording and
processing device should be of robust, tamper-proof design with read-only
capability.
7.2 The recording and
processing device should record, whenever the EGCS is in operation, the data
described in 4.4.7, 5.4.2, and 10.3 as applicable, including overboard
discharges from any associated tanks within the system, against UTC and ship's
position as given by a Global Navigational Satellite System (GNSS) and whether
the ship was inside or outside an Emission Control Area as given by regulation
14.3 at that time. The device should also be capable of:
.1 (Scheme B only) being automatically set, or
pre-set, with the Emission Ratio limit value as appropriate to the sea area, in
relation to regulation 14.3, where the ship is operating;
.2 being automatically set, or pre-set, with
the applicable overboard pH limit value;
.3 being automatically set with the
applicable PAH limit value;
.4 recording the aggregated time in excess of
15 minutes over any rolling 12-hour period that the differential PAH value is
above the set limit value by more than 100%;
.5 being pre-set with the applicable turbidity
limit value;
.6 recording the aggregated time in excess of
15 minutes over any rolling 12-hour period that the rolling average
differential turbidity value is above the set limit value by more than 20%; and
.7 recording preset and
set limit values.
7.3 The recording and
processing device should be capable of preparing reports over specified time
periods.
7.4 Data should be
retained for a period of not less than 18 months from the date of recording. If
the device is changed over that period, it should be ensured that the required
data is retained on board and available as required for inspection.
7.5 The device should
be capable of downloading a copy of the recorded data and reports in a readily
useable format clearly indicating periods of non-compliance. Such copy of the
data and reports should be available to the Administration or port State
control as requested.
8 ONBOARD MONITORING
MANUAL (OMM)
8.1 An OMM should be
prepared to cover each EGCS installed in conjunction with a fuel oil combustion
unit, which should be identified, for which compliance is to be demonstrated.
8.2 The OMM should, as
a minimum, include:
.1 for extractive exhaust gas sampling
systems, the position from which the gas sample is drawn together with details,
arrangement and operating ranges of the analysers and all necessary ancillary
components or requirements including, but not limited to, sample probe
assembly, sample transfer line and sample treatment unit;
.2 for in situ exhaust gas analysers, the
location and arrangement of the analyser in the exhaust duct, operating ranges
and all necessary ancillary components or requirements;
.3 for inlet water and discharge water
monitoring, the positions from which the water samples are drawn, the location and
arrangement of the analysers together with details of any necessary ancillary
services such as sample transfer lines and sample treatment units;
.4 the analysers to be used for monitoring of
exhaust gas, inlet water, discharge water, their service, maintenance, and
calibration requirements. Templates covering the minimum information which
should be included are provided in appendix 5;
.5 the zero and span check procedures of the
exhaust gas analysers and calibration of washwater, discharge water and inlet
water analysers together with reference materials to be used and the required
frequency of those checks;
.6 the operating parameter instruments to be
used described in 4.4.7 or 5.5.2;
.7 the installation, operation, adjustment,
maintenance, servicing and calibration requirements and procedures of the
analysers, associated ancillary equipment and operating parameter measurement
instruments;
.8 the means by which ongoing compliance
would be temporarily indicated in the case of the failure of a single
monitoring device, taking into account that transitory periods of emission
exceedances and/or isolated spikes in the recorded output in the Emissions
Ratio do not necessarily mean non-compliant exceedance of emissions and should
therefore not be considered as a breach of the requirements;
.9 the data recording system and how it is to
be operated, data retained and the types of reports which it can produce;
.10 guidance as to data or other indications
which may signify a malfunction of either an analyser, an item of ancillary
equipment or an operating parameter sensor together with the fault-finding and
corrective actions which should be taken;
.11 other information or data relevant to the
correct functioning or use of the monitoring system or its use in demonstrating
compliance; and
.12 where the information
described in .1 to .11 above is referring to detailed descriptions of
procedures, reference can be made to additional documents (e.g. manufacturer's
documentation) which should be considered part of the OMM.
8.3 The OMM should
specify how the EGCS, operating parameter measurement instruments and the
exhaust gas and discharge water monitoring systems are to be surveyed in order
to verify that:
.1 the EGCS conforms to the ETM-A or ETM-B as
applicable;
.2 the operating parameter instruments
installed and used on board are as approved per the OMM;
.3 the exhaust gas and discharge water
monitoring systems used on board are as approved per the OMM;
.4 inspection, maintenance, servicing,
calibration and adjustments have been undertaken as required and those actions
recorded in the EGCS Record Book as required; and
.5 the operating
parameter instruments and the exhaust gas and discharge water monitoring
systems are correctly functioning.
8.4 Under scheme B,
where operation of the EGCS is required in order to demonstrate the
functionality of the monitoring system during installation or initial surveys,
the OMM should describe the operational condition(s) which demonstrate the
operational behaviour of the monitoring system and which should be used when
surveying in accordance with paragraph 5.3.1. The description of operational
condition(s) may include:
.1 the connected fuel
oil combustion unit load point(s); and
.2 the minimum operating
time at a given load point.
8.5 The OMM should be:
.1 approved by the
Administration; and
.2 retained on board
the ship onto which the EGCS is installed and should be available for surveys
as required.
9 SHIP COMPLIANCE
9.1 SOX
Emissions Compliance Plan (SECP)
9.1.1 For a ship which is
to use an EGCS, in part or in total, as an approved equivalent means to the
requirements given by regulation 14.1 or 14.4 of MARPOL Annex VI there should
be an SECP for the ship, approved by the Administration.
9.1.2 The SECP should list
each fuel oil combustion unit which may use fuel oil supplied in accordance
with the requirements of regulations 14.1 and/or 14.4 of MARPOL Annex VI.
9.1.3 The SECP should list
each fuel oil combustion unit which may use Scheme A and/or B of these
Guidelines together with identification of the EGCS to which it is connected
and whether this control may be applied continuously or only inside or only
outside the Emission Control Areas given by regulation 14.3 of MARPOL Annex VI.
9.1.4 The SECP should
advise that records should be kept of actions initiated to meet the requirement
of these Guidelines in case of breakdown of the EGCS or associated equipment,
and that the relevant flag and port State's Administration should be notified,
in accordance with MEPC.1/Circ.883/Rev.1.
9.2 Demonstration of
compliance
9.2.1 Scheme A
9.2.1.1 The SECP should
refer to, not reproduce, the ETM-A, EGCS Record Book or engine-room logger
system and OMM as specified under Scheme A.
9.2.1.2 For all fuel oil
combustion units listed under 9.1.3, details should be provided demonstrating
that the rating and restrictions for the EGCS as approved, under 4.2.2.1.2, are
complied with.
9.2.1.3 Required parameters
should be monitored and recorded as described in 4.4.7 when the EGCS is in
operation in order to demonstrate compliance.
9.2.2 Scheme B
9.2.2.1 The SECP should
refer to, not reproduce, the ETM-B, EGCS Record Book or engine-room logger
system and OMM as specified under Scheme B.
10 DISCHARGE WATER
10.1 Discharge water
quality criteria1
____________________
1 The discharge water
quality criteria should be reviewed in the future as more data become
available, including relevant research and development results, on the content
of discharge water and its effects, taking into consideration any advice given
by GESAMP. Guidance for voluntary discharge water data collection is included
in appendix 3.
10.1.1 EGCS discharge water
should comply with the following criteria prior to being discharged into the
sea:
10.1.2 pH criteria
10.1.2.1 The discharge
water pH should comply with one of the following requirements, which should be
recorded in the ETM-A or ETM-B as applicable:
.1 The discharge water should have a pH no
lower than 6.5 measured at the ship's overboard discharge with the exception
that, during manoeuvring and transit, a maximum difference of 2 pH units is
allowed between the inlet water and overboard discharge values.
.2 The pH discharge limit, at the overboard
monitoring position, is the value that will ensure a pH no lower than 6.5 at a
distance of 4 m from the overboard discharge point with the ship stationary,
and is to be recorded as the overboard pH discharge limit in the ETM-A or
ETM-B. The overboard pH discharge limit can be determined either by means of
direct measurement, or by using a calculation-based methodology (computational
fluid dynamics or other equally scientifically established empirical formulae)
as agreed by the Administration, and in accordance with the following
conditions to be recorded in the ETM-A or ETM-B:
.1 all EGC units connected to the same
outlets are operating at their full loads (or highest practicable load) and with
fuel oil of the maximum sulphur content for which the units are to be certified
(Scheme A) or used with (Scheme B);
.2 if a test fuel with lower sulphur
content, and/or test load lower than maximum, sufficient for demonstrating the
behaviour of the discharge water plume is used, the plume's mixing ratio must
be established based on the titration curve of seawater. The mixing ratio would
be used to demonstrate the behaviour of the discharge water plume and that the
overboard pH discharge limit has been met if the EGCS is operated at the
highest fuel sulphur content and load for which the EGCS is certified (Scheme
A) or used with (Scheme B);
.3 where the discharge water flow rate is
varied in accordance with the EGCS gas flow rate, the implications of this for
the part load performance should also be evaluated to ensure that the overboard
pH discharge limit is met under any load;
.4 reference should be made to a seawater
alkalinity of 2.2 mmol/L and pH 8.2;2 an amended titration curve
should be applied where the testing conditions differ from the reference
seawater, as agreed by the Administration (example titration curve for
reference seawater conditions is presented in appendix 4); and
.5 if a
calculation-based methodology is to be used, details should be submitted to
allow its verification such as but not limited to supporting scientific
formulae, discharge point specification, discharge water flow rates, designated
pH values at both the discharge and 4 m location, titration and dilution data.
_________________
2 These values could be
revised within two years for new installations following the adoption of these
amended Guidelines upon further inputs on the physical state of the seas
resulting from the use of exhaust gas cleaning systems.
10.1.3 PAHs (Polycyclic
Aromatic Hydrocarbons)
10.1.3.1 The discharge
water PAH should meet the criteria below. The appropriate limit should be
specified in the ETM-A or ETM-B.
10.1.3.2 The maximum
continuous PAH concentration in the discharge water should not be greater than
50 µg/L PAHphe (phenanthrene equivalent) above the inlet water PAH
concentration. For the purposes of this criterion, the PAH concentration in the
discharge water should be measured downstream of the water treatment equipment
including any reactant dosing unit, if used, but upstream of any dilution for
control of pH, if used, prior to discharge.
10.1.3.3 The 50 µg/L limit
described above is normalized for a discharge flow rate, before any dilution
for pH control, of 45 t/MWh where the MW refers to the aggregated MCR of all
those fuel oil combustion units whose EGCS discharge water PAH is being
monitored at that point. In cases where sensors are installed in a separate
measurement cell, the PAH limit applies to the flow in the main discharge pipe
from which the water is bypassed. This limit would have to be adjusted upward
for lower washwater flow rates (t/h) per MW, and vice versa, according to the
table below.
Table 5: Criteria for discharge water PAH concentration
Specific Discharge Water flow rate (before dilution for pH control) (t/MWh) |
Discharge concentration limit (µg/L PAHphe equivalents) |
Measurement technology |
0-1 |
2250 |
Ultraviolet light* |
2.5 |
900 |
- " -* |
5 |
450 |
Fluorescence3 |
11.25 |
200 |
- " - |
22.5 |
100 |
- " - |
45 |
50 |
- " - |
90 |
25 |
- " - |
* Alternative measurement
technologies may be used with the agreement of the Administration.
_________________
3 For any flow rate >
2.5 t/MWh fluorescence technology should be used.
10.1.3.4 For an aggregated
15-minute period in any rolling 12-hour period, the continuous PAHphe concentration
limit may exceed the limit described above by up to 100%. This would allow for
an abnormal start-up of the EGC unit.
10.1.4 Turbidity/Suspended
particulate matter
10.1.4.1 The discharge
water treatment system should be designed to minimize suspended particulate
matter, including heavy metals and ash. The turbidity of the discharge water,
following treatment equipment, including any reactant dosing, but upstream of
any other dilution unit, if used, should meet the criteria below. The limit
should be recorded in the ETM-A or ETM-B.