sulphur compliance methods: sox scrubbers and marine

MARINE ENVIRONMENT DIVISION

Sulphur Compliance Methods:

SOx Scrubbers and Marine Alternative Fuels

Seminar on the regulations and reduction

of air emissions from ships

Bangkok, Thailand, 27 June 2019

Dr Zabi Bazari

IMO Lead Consultant


Content

• Regulatory requirements and drivers

• Compliance options:

• Multi-fuel option

• Exhaust Gas Cleaning System (SOx Scrubbers)

• LNG as marine fuel

• Biofuels

• Other fuels and their overall comparisons


Regulatory drivers for change

Reg. 14 Sulphur Oxides & Particular Matter (SOx & PM)

Significant reduction in

regulatory sulphur levels.

Compliance options:

1. Use of compliant fuel oil

(e.g. low sulphur fuel)

2. SOx scrubbers

3. LNG


• Sets a target of 50% reduction in GHG

emissions from international shipping

by 2050 relative to 2008.

• Compliance options

• Such a big reduction almost certainly

will need new low-carbon or zero-

carbon fuels.

• Thus, regulatory scene for:

• Short term is driven by SOx

concerns.

• Long–term is driven by CO2

concerns.

Initial IMO GHG Strategy


ECA compliance strategies - SOx

Option 1. Use compliant fuel oil (e.g. low sulphur fuel)

→ Multi–fuel bunkering

• Fuel system segregation (various tanks as a minimum).

• Segregated cylinder lube oil tanks may be required.

• Fuel change over and log book recording needed for ECA-SOx

operation.

• More complex system and therefore more vigorous “fuel management”.

• Planning of voyages for having correct fuel onboard prior to entering an

ECA-SOx.

• Cost concerns / availability concerns / fuel quality concerns


Option 2 - SOx Scrubber (EGCS)


EGCS (Exhaust Gas Cleaning System)

• EGCS is the term used by the IMO for

SOx scrubbers.

• Regulation 4 of MARPOL Annex VI

allows the use of “equivalents”; subject

to approval by the Flag Administration.

• EGCS has been accepted by IMO as

an “equivalent” method to sulphur

compliance.


SOx scrubber – How does it work?

• Processes:

• PM also ends up in

washwater.

• NOx is also partially

converted to acids

(nitrous or nitric)


SOx scrubber: How does it work?

• SOx is removed via using

wash water.

• System includes:

• Water supply

• Water treatment

• Exhaust gas monitoring

• Water quality monitoring

• Supply of water treatment

agent

• Types of scrubbers:

• Open loop

• Closed loop

• Hybrid (open/closed)Source: Force Technology, 2012

See: http://www.youtube.com/watch?v=J8_D7ASh0_g

http://www.youtube.com/watch?v=J8_D7ASh0_g


Scrubber – Monitoring of exhaust gases for compliance

• Compliance method via monitoring

according to MEPC.259(68) :

• Ratio of SO2 (ppm) to CO2(% v/v)

should be according to the table.

• The Table is valid when petroleum

based distillates or residuals are

used.

Source: ABS Advisory on “Exhaust Gas Scrubber Systems”


Scrubber – Monitoring of wash-water quality

The following parameters need to be monitored:

• pH > 6.5 (with some exceptions)

• PAH (Polycyclic Aromatic Hydrocarbons) has specific limits < 50 micro gram/Litre

PAH when flowrate is 45 t/MWh (normalised value).

• Turbidity/suspended particles: Need to be limited and continuously monitored

and be below certain limits.

• Nitrates: These need to be monitored and specific limits observed. The limit is

below 60 mg/litre for a capacity of 45 tonnes/MWh (normalised value).

• Specific techniques or standards are given for wash water monitoring equipment.


Scrubber certification – Applicable regulations

The IMO EGCS Guidelines (MEPC.259(68)) permit two schemes for survey and

certification purposes:

• Scheme A (Unit Certification with periodic Emissions and Parameter Checks)

• Scheme B (Continuous Emission Monitoring with Parameter Checks).

The Guidelines make provisions for each EGCS’s:

• Approval

• Survey and certification

• Emissions limits and emissions monitoring

• On-board demonstration of compliance

• Washwater criteria

• Washwater monitoring


• SOx Emissions Compliance Certificate (SECC) for systems certified based on

Scheme A.

• EGCS Technical Manual (ETM): Includes all technical details of the system

including verification methods.

• Approved SOx Emissions Compliance Plan (SECP): This is for a ship that has

EGCS and indicates how the ship overall is going to comply with sulphur

regulation.

• EGCS Record Book: For recording of changes to the system in terms of

maintenance, EGCS residue, supply of agents, etc.

• On-board Monitoring Manual (OMM): Details all aspects of monitoring system for

exhaust gases and washwater.

• All the above need to be approved by Flag Administration and are also subject to

Port State Control.

Documentations required on-board


Scrubber residues – Delivery to port reception facilities

• All residues from water treatment plant should be kept on board.

• They cannot be incinerated on-board and must be delivered to reception facilities.

• All information about EGCS residues (storage, delivery, times, dates, quantities,

location, etc.) should be recorded in an EGCS Record Book.

• EGCS Record Book could be an independent one or be part of existing log books,

or an electronic recording system as approved by Administration.


• Concerns on washwater quality and its impacts

• Some countries set limits for the content of pollutants in ports, estuaries and

coastal areas.

• This may mean that the discharges of washwater in some areas will face

restrictions.

• In some areas, washwater discharges might be prohibited by port State

legislation.

• The resulting lack of harmonisation / clarity will hamper the uptake of

scrubbers.

• To alleviate the above concerns, MEPC 74 (May 2019) agreed to include

investigation of this matter at PPR 7 with a reporting back by 2021.

• MEPC 74 also encouraged GESAMP to establish a task team to assess the

available evidence relating to the environmental impact of discharges of EGCS

effluent.

EGCS (Open-loop SOx Scrubber) concerns - Uncertainties


Option 3 - Liquefied Natural Gas

(LNG) as Marine Fuel


LNG as marine fuel

• Natural gas is mainly methane (~ 95%) with some ethane and propane

(together about 2-3%)

• Cooled to around -162°C, at which point it contracts by a factor of

600:1 to form a liquid

• LNG is re-gasified before burning in engines or boilers

• Clean fuel (SOx and PM are negligible)

• LNG may be used to meet the NOx Tier III


LNG as compared to liquid fuels

• Volumetric energy density of LNG is less than FO (fuel oil)

• LNG (22 TJ/m3) and FO (39 TJ/m3)

• Mass energy density of LNG is higher than FO

• LNG (55 MJ/kg) and MDO (42.8 MJ/kg)

• Almost no sulphur

• Very low flash point at ~ -149 0C (gas oil is ~74 0C).

• Vey high auto-ignition temperature of 540 (Gas Oil is ~315 0C) – Thus

combustion need to start externally.

• Dual fuel engines

• Spark ignited engines


Dual fuel engines: Basic principles

• Work according to diesel principle (Compression Ignition).

• Liquid fuel is used as pilot injection to initiate combustion.

• NG is mixed with air prior to pilot injection.

• The design could facilitate a varied ratio between liquid fuel and LNG.

Source: Wartsilla


Pure natural gas engines


• Works with 100% gas.

• Single fuel natural gas engines

• Low pressure gas

• Spark plugs initiate combustion:

• Works according to Otto cycle

• Less efficient than the diesel

options

Source: Rolls Royse (Bergen K-GE)


LNG emissions compared to HFO and MDO

http://www.naftrade.com/uploads/8/0/2/5/8025081/lng.pdf


LNG as fuel: Other

considerations

• DF and pure natural

gas engines have

some Methane Slip

• LNG has a significantly

more Supply Chain

GHG Emissions

(upstream) as

compared to liquid

fuels

Source: ICCT White Paper on Assessment of the fuel cycle impact of liquefied natural gas as used in international shipping


IMO - LNG studies

Main studies / initiatives performed:

• Feasibility study on the use of LNG as a

fuel for international shipping in the

North American ECA

• Pilot study on the use of LNG as a fuel

for a high speed passenger ship from

the Port of Spain ferry terminal in

Trinidad and Tobago

• Feasibility study on LNG fuelled Short

Sea and Coastal Shipping in the Wider

Caribbean Region


LNG as fuel regulatory aspects: IGF Code

• IMO IGF Code “International Code of Safety for Ships using Gases or other Low-Flash Point Fuels”.

• Harmonised with IGC Code with more focus is on bunkering and fuel management aspects.

• There is no specific rule on LNG as marine fuel in MARPOL Annex VI

IGF Code contents:

1. Preamble

2. General

3. Goals and functional requirements

4. General requirements

5. Ship design and arrangement

6. Fuel containment system

7. Material and general pipe design

8. Bunkering

9. Fuel supply to consumers

10.Power generation and propulsion

11.Fire safety

12.Explosion protection

13.Ventilation

14.Electrical installations

15.Control, monitoring and safety

system.


LNG: Pros and cons

Pros

• Clean fuel:

• No sulphur

• Up to 90% less NOx

• No Particulate Matters

• GHG reduction potential

• LNG is often cheaper than MGO when available

• Less engine maintenance?

Cons

• Lack of infrastructure for LNG bunkering

• LNG safety issues

• Cost of LNG ships

• Range of LNG ships

• Methane slip

• Port operation: Likely need for BOG gas combustion

• Reduced cargo space

• Large fuel tank volumes due to low energy density and need for insulation and containment


Vessels expected to use LNG as marine fuel: Main features

• Operate mostly inside the ECA, e.g. short sea shipping

• Coastwise and regionally bound vessels, e.g. ferries, tugs, offshore vessels

• Fuel cost sensitivity

• Sufficient size and on-board space to accommodate the installation

• LNG bunker availability and cost

• Possibilities for conversion

• Fleet renewal demand

• Liner service, vessel on fixed routes

• Environmental profile is beneficial


Comparison of compliance alternatives



Other Alternative Fuels


Biofuels


Bio-fuels production from bio-mass


Biofuels generations


• The production cycle include production of bio-material and process conversion (all would require land, energy, water, etc.).

• Depending on the above, biofuels are divided into generations:

• 1st generation: Produced directly from food crops (wheat, sugar, etc.)

• 2nd generation: Produced from non-food crops such as wood, organic waste, food crop wastes, food wastes, etc.

• 3rd generation: Based on specially engineered energy crops

such as algae with no impact on food/dforestation.


Biofuel production

• Currently mainly produced from food crops.

• Production involves:

• Land use

• Energy use

• Fertilizer use

• Water use

• Production of biofuels are generally subsidised.

• Sustainable production of biofuels is currently an issue.

• Sustainable production potential is currently limited worldwide.


Diagram source: http://www.geni.org/globalenergy/library/articles-renewable-energy-transmission/graphics/biofuels_compare.gif

The lifecycle “CO2 performance” of various bio-fuels vary significantly.

How green are biofuels?


Methanol


• Traditionally methanol is produced from wood but now mostly through “industrial

synthesis” from natural gas

• Methanol has the advantage of remaining liquid at ambient temperature

• Methanol and LNG are similar in terms of energy density

• Low emissions fuel

Stena Germanica ferry converted to methanol


Methanol: IMO Study


• A study was done for IMO. The main conclusions are:

• Methanol produced from natural gas (synthetic methanol) has higher GHG

emissions than conventional fuels.

• Methanol produced from biomass (bio methanol) have the potential to reduce

emissions provided that the electricity used for its production is clean.

• The lifecycle NOx emissions of methanol is 45% of conventional fuels per unit

energy

• The lifecycle SOx emissions of methanol is approximately 8% of those from

conventional fuels per unit energy

• Technology Readiness exists to a large extent and feasible. However, there are

additional safety barriers.

• From cost/economic perspective, methanol can only be justified if MGO prices

are high and the ship is largely operating in ECA zones.


Biodiesel


FAME (Fatty Acid Methyl Esters )

• Biodiesel refers to a mixture of

different FAME.

• FAME is produced from vegetable

oils, animal fats and waste cooking

oils.

• FAME has physical properties similar

to those of conventional diesel.

• It is also non-toxic and

biodegradable.

Source: European Biofuel Technology Platform, factsheet


Biodiesel pros

• Clean burning – No SOx, HC or PM; reduced CO2

• Biodegradable in water / non-toxic / high flash point 1600C

• Usable in existing diesel engines with little or no modification

• Improves lubricity – additive for ultra low sulphur distillates

• Blends well with petroleum diesels.


Biodiesel issues

• Limited availability

• Food-fuel links, impact on food production

• Relatively expensive and normally subsidised.

• Cold filter plugging properties: Low temperature issues

• Solvent may degrade rubber & attack lead, copper, brass, zinc

• Oxygen Content 10-12 %

• Lower Heating Value than fossil fuel

• Fuel stability issues: Storage max 6 months recommended.


• Hydrogen (H2) is the

candidate fuel.

• Production mainly from

renewable electricity.

• Supplement to LNG and

other gaseous fuels.

• Long term prospect

positive.

• Compatible with fuel cell

technology as well as

future hybrid electric

propulsion zero-carbon

ships.

Renewable electricity marine energy pathway - Hydrogen

Batteries Synthetic fuel


Ammonia (NH3) as Marine Fuel

(a form of synthetic fuel)

Image courtesy of C-Job-Naval-Architect, Netherlands, https://www.maritime-executive.com/article/new-research-shows-benefits-of-ammonia-as-marine-fuel

https://www.maritime-executive.com/article/new-research-shows-benefits-of-ammonia-as-marine-fuel


“Green ammonia” as marine fuel

• “Green Ammonia” has recently

been advocated as a marine fuel.

• Green Ammonia refers to

ammonia produced using

renewable electricity.

• Existing ammonia (not-green) is

produced from fossil fuel and is

highly energy-intensive, water-

intensive and GHG-intensive

material.

• Green Ammonia is thus fully

linked to renewable electricity

sector.


• Current not-green ammonia

• Used by the international fertiliser industry

• Global market and international transportation already exist.

• Production is based on use of fossil fuels (highly GHG-intensive).

• Existing ammonia as marine fuel is much worse than fossil fuels.

• Future green ammonia: When developed, it will provide advantages:

• Existing global logistics infrastructure (unlike e.g. hydrogen).

• Does not require cryogenic storage (unlike e.g. hydrogen).

• Energy density of liquid ammonia is reasonable (unlike e.g. batteries).

• Changes to ship engines or future fuel cells technologies are feasible.

• Although toxic, corrosive and unsafe, the risk profile can be managed.

Green versus not-green ammonia


Ammonia properties

• Ammonia liquefies at -33 oC; or at a moderate pressure of 10 bar.

• Requires less energy for liquefaction than H2 / Less boil off gases

• Liquid ammonia requires 46% less on-board storage space than H2

• Lower fire risk compared to H2 (narrower flammability range and

higher ignition temperature).

• Heating value is 18.67 MJ/kg; less than half of current marine fuels.

• Production is water intensive (~1.5 tonne water/tonne ammonia) and

energy intensive (~28 MJ/kg when natural gas is used as feedstock).


Ammonia as marine fuel: Pathways

• Production from renewable energy is key.

• Three main pathways:

• Pathway 1: As H2 carrier thus conversion back to H2 and then use. Fuel cell is ideal technology.

• Pathway 2: As a primary fuel via burning in dual fuel engines.

• Pathway 3: As a mix of pathways 1 and 2.


Ammonia as marine fuel - Emissions

• Green ammonia will produce significantly less life-cylce GHG

emissions.

Source: Sailing on Solar, Environmental Defence Fund and Riccardo report, 2019


Solar-to-liquid fuels (green kerosene for jet fuel)

• A new technology for converting solar energy into liquid synthetic fuel.

• SUN-to-LIQUID project (EU funded) has recently produced its “solar kerosene” under real field conditions, using sunlight, water and CO2.

• The project has developed a solar reactor, located at the top of a tower, to reach reaction temperatures of more than 1,500 °C.

• The solar reactor then synthesizes hydrogen and carbon-monoxide, produced from water and CO2.

• Compared to conventional fossil-derived jet fuel, the net CO2 emissions to the atmosphere can be reduced by more than 90%.

• The produced fuel is a drop in one for aviation.


Summary of alternative marine fuels and conclusionIFO LSFO MGO FAME Methanol LPG LNG

Engine and fuel

system costDrop-‐in Drop-‐in Drop-‐in Drop-‐in Dual fuel Gas tank

Dual fuel

Cryo tanks

Projected fuel

costRefining Refining Land use

Infra-‐

structure

Infra-‐

structure

Emission

abatement cost

SOx, NOx,

PM, CO2

NOx,

PM, CO2

Safety related

costFlash point Venti lation Press/temp

Indirect cost Ethics Cargo space Cargo space Cargo space

Serious impediment

Signifficantcost

Feasible solution available


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London

SE1 7SR

United Kingdom

Tel: +44 (0)20 7735 7611

Fax: +44 (0)20 7587 3210

Email: [email protected]

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sulphur compliance methods: sox scrubbers and marine

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