Wärtsilä NO X Reducer Wärtsilä NO X Reducer Environmental Efficiency June 2011
Environmental efficiency • Stringent legislations concerning NO X. • Retroactive legislations are introduced. • Regulations in the shape of fees, taxes or incentive programs are brought on from many parties including individual countries that have parties, including individual countries that have introduced fairway dues, NO X tax or NO X fund initiatives. June 2011
Revised Marpol Annex VI Regulation 13 NO X (g/kWh) 18 16 Primary methods operation area Primary methods operation area Tier I >130 kW 14 New ships 2000 12 10 Tier II >130 kW 8 Wärtsilä NOR New ships 2011 6 operation area Secondary methods operation area 4 Tier III >130 kW N New ships 2016 in hi 2016 i 2 designated Emission Control Areas (ECA) 0 0 200 400 600 800 1000 1200 1400 1600 1800 2000 Rated engine speed (rpm) June 2011
NO X formation and reduction • Nitrogen Oxides (NO x ) are formed g ( x ) during the combustion process from oxygen (O 2 ) and nitrogen (N 2 ) in air. • The NO X Reducer SCR catalyst converts NO X molecules back to harmless O 2 and N 2 molecules by y 2 2 means of urea. June 2011
NO X reducer – description • The Nitrogen Oxide Reducer (NOR) is designed by Wärtsilä and is based on selective catalytic reduction (SCR) technology. The NO X b d l ti t l ti d ti (SCR) t h l Th NO reducer portfolio covers Wärtsilä’s medium-speed engine portfolio for marine applications. • The size of the NO X Reducer is optimised in terms of modularity, performance and costs. The typical NO X emission reduction is 90 %. • The main component of the NO X reducer installation is the reactor with the catalyst inside. Other modular essential parts of NOR system are a reagent pumping unit a reagent dosing unit a control unit and an reagent pumping unit, a reagent dosing unit, a control unit and an injection unit. June 2011
NO X reduction functional principle (SCR) Nitrogen oxides (NO X ) are reduced into nitrogen (N 2 ) and reduced into nitrogen (N 2 ) and water vapour (H 2 O) using ammonia or urea at a suitable temperature on the surface of the t t th f f th catalyst. Operating temperature ~ 300 – 450 °C 300 450 C June 2011
Minimum recommended temperature in the SCR inlet vs fuel sulphur content June 2011
Proven catalytic elements for marine applications. pp y Catalytic elements June 2011
NO x Reducer layout Soot blowing NOR reactor Control system cables Compressed air Urea piping Compact unit (dosing & control) Compressed air Urea tank Urea tank Injector Injector Pump unit June 2011
Wärtsilä NOR system overview Dosing / Dosing / Dosing / Dosing / Control Control Control unit unit unit June 2011
Main components – Reactor • Wide range of sizes designed for various customers’ needs. various customers needs. • High level of standardization and modularisation. • Reactor structure optimized for marine applications. • Reactor can be run without reagent Reactor can be run without reagent injection, only soot blowing remains in operation; no by-pass is required. • Soot blowing inlets are located on S t bl i i l t l t d opposite reactor walls for ensuring efficient cleaning which covers the whole element surface area. h l l t f June 2011
Main components – Urea injection and mixing • The injection unit feeds the optimum amount of urea solution with air to the mixing duct g • Mixing duct gives the necessary time for urea to evaporate, decompose and mix with p , p exhaust gas • Appropriate mixing duct arrangement ensures pp p g g uniform flow around the injector to obtain homogeneous distribution of ammonia into the flow • When turned off, the injector is automatically purged by compressed air from urea solution in order not to have urea deposits in it in order not to have urea deposits in it. June 2011
Main components – Urea pumping unit • The pumping unit supplies urea solution to multiple dosing units • In large multiple engine installations it is possible to simply increase the number of pumps in order to deliver the desired amount of urea • All piping is made of stainless steel • Preferably accommodated close to the urea tank June 2011
Main components – Urea dosing unit • Defines the correct dosing rate and adjusts urea flow accordingly with a control valve. • Combines the control of urea solution dosage and compressed air with automatic d d d i ith t ti injector cleaning features. • All piping is made of stainless steel. • An independent dosing unit for each NOR reactor. • Recommended to be installed close to the urea injector. June 2011
Main components – Control system • The control system is a part of the dosing unit g • Controls the NOR operation by monitoring engine parameters monitoring engine parameters • Integrated interface to the engine automation system automation system • Hardware and software commonality with the engine automation system UNIC platform • Soot blowing control and safety features are included June 2011
Wärtsilä NOR performance • High activity over a wide temperature range g • Efficient SCR process • Durable catalyst against ageing and erosion erosion Performance NOx emission levels as per IMO Tier III* Urea consumption p Typically 15-20 l/h / MW yp y Operation Fuels: MGO / MDO / HFO with <1.0 % S content (higher sulphur content possible upon request) ( g p p p q ) NOR delivery means ensuring the compatibility of the NOR system with the engine. *at sufficient high exhaust temperature conditions June 2011
Selection of NOR reactor for Wärtsilä engines June 2011 • NOR reactor is selected according to engine power.
NO X reducer system – typical consumables • Reducing agent • Compressed air for reducing agent injection and soot blowing Compressed air for reducing agent injection and soot blowing • Electricity (~1 kW per NOR unit) • Catalytic elements TYPICAL COST DISTRIBUTION June 2011
NOR Benefits Owner Benefits Shipyard Benefits • Quality and functionality guaranteed • Fully integrated supply by by Wärtsilä one supplier • C Control system commonality for t l t lit f • P Possible integration with noise ibl i t ti ith i NOR and the engine attenuation system • • Complete system user manual Complete system user manual • • Single point responsibility Single point responsibility • Catalyst system components and • Quick installation due to pre- service available by Wartsila y fabricated and -tested modules worldwide • Start up and commissioning • Training courses • Calibration expertise • Short delivery time June 2011
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