WP3 Exhaust Gas Cleaning Love Hagström D.E.C. Marine AB
WP3 Layout NOx Primary reduction methods After treatment SCR SOx PM Wet Scrubber Dry Scrubber Particulate filter DPF
Primary NOx reduction methods EffShip Engine methods Fuel injection/ valve timing Fuel nozzle design Wet methods Direct water injection, DWI Inlet air humidification, HAM Wt Water/ /fuel emulsification EGR Exhaust gas recirculation
Wet methods EffShip DWI (Direct Water Wt Injection) HAM (Humid Air Motor) up to 50% NOx reduction up to 70% NOx reduction Heat absorption by added water Lower peak temperatures
EGR Exhaust Gas Recirculation Less oxygen in inlet air Slower combustion Up to 70% NOx reduction [MAN]
SCR Selective Catalytic Reduction Urea consumption <5% of fuel cons. (TierIII) NOx + Urea Nitrogen + Water Power consumption <0.1% of engine power Injection air for urea atomization Dust blow for preventing ash deposit
SCR Selective Catalytic Reduction Vanadium (V 2 O 5 /TiO 2 ) catalyst blocks Withstands SOx in exhaust gas Large contact surface & open area Operation temperature 270 500 C
EffShip Pre turbo SCR Higher exhaust pressure Higher exhaust temperature Suitable for 2 stroke engines FFinal Seminar, G Gothenburg, M March 21, 2013 3 Pre turbo SCR
OXI Oxidation Catalyst CO SCR + OXI NOx 99% 100% VOC 90% PM 50% 0% NOx SCR VOC OXI CO 90%
NOx reduction summary Engine modifications Water methods EGR SCR Compliance Tier II Tier II Tier II III Tier III Fuel penalty YES YES YES NO PM/ Soot INCREASE INCREASE INCREASE DECREASE
Open loop Sea water Scrubber py g y g g p Open loop Sea water once through SOx + Seawater Sulphates Sulphates out to sea Oil/ Soot to sludge Dilution to ph>6 Fcopyright Lloyds register group Limited
Closed loop Fresh water Scrubber EffShip py g y g g p Closed loop Sox + Fresh water + NaOH Sulphates Recirculation of scrubbing water Sulphates out with bleed off Oil/ Soot to sludge Fcopyright Lloyds register group Limited
Scrubber tower design Scrubber tower Maximize liquid/gas contact Maximize reaction time Lowering temperature Corrosion resistant material Images copyright NC State University Co current flow packed wet film tower Fg py gy
Scrubber tower design Wet film tower/ venturi AVC Advance Vortex Chamber GTM in line scrubber [Wärtsilä] [Clean marine] [Green tech marine]
Otherwet scrubber types Hybrid wet scrubbers Can use either open or closed loop cycle Requires both sea water and fresh water system ULF Scrubber (CSNOx) Ultra low frequency waves makes wash water reactive Reduces SOx (SAE), CO2 and NOx (CNR) Pilot installation of open loop system 2009 Interest for ULF has diminished due to lack of reports [Ecospec]
Dry scrubber EffShip Dry adsorbtion unit Operation temperature 240 440 C SOx adsorbs onto CaOH granules (Limestone), transforms to gypsym Onshore disposal of reacted granules (20% more weight after reaction) [Couple Systems] No discharge into sea
SOxscrubber comparison Position Wet Scrubber After SCR/ Boiler Dry Scrubber Before Boiler
SOxscrubber comparison EffShip
SOxscrubber comparison EffShip
DPF Diesel Particulate Filter Wall flow Honeycomb Ultra low sulphur fuels only! Regeneration temperature DPF 550 600 C CDPF 400 450 C CDPF + OXI 320 350 C
WP3 Summary Primary NOx reduction Up to 70% NOx reduction with EGR/ water Fuel penalty & increased PM SCR Over 95% NOx reduction Proven maritime technology No fuel penalty but requires urea CDPF Over 90% PM reduction Only ULSF fuels SOx Scrubbers Up to 99% SOx reduction Only few pilot installations Heavy and voluminous OXI Boosting SCR and CDPF VOC, CO & PM reduction