INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 1 Reviewer Meeting, Brussels, 8 th April, 2011 SPB2 Aftertreatment for Passenger Car CNG Engine Aftertreatment system for PC CNG gas engine with special regard on CH4 conversion, assessment of options for NOx abatement

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 2 Introduction – Answers to Reviewers Comments DAIMLER

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 3 1. Counter current HEX with 3-way catalyst (TWC) SPB2: Technical Approach Methane air Cold start burner TWC - Integrated system (catalytic coated HEX) - Amplification of adiabatic temperature rise - Efficient control of catalyst operation temperature 3. Engine measures - for faster light-off without fuel penalty - Lambda strategies for enhanced CH4 conversion TWC 2. Improved catalyst material for better CH4-lightoff Three technological approaches for improving the methane conversion

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 4 SPB2: Technologies and Approach (modifications Amendment II) Development of specific active methane oxidation catalysts (WPB2.2) Catalyst preparation (precious metal and metal oxide technologies) Test of powdered catalysts, structured catalysts, substrates (metal and ceramics) Characterization studies Development of a dedicated thermal management system (WPB2.3) Design and set-up of an integrated exhaust gas heating device (catalytic coated HEX) Modelling of heating device and catalytic combustion, simulation of behaviour Manufacturing, testing and optimisation of HEX Development of operation strategies on engine test bench (WPB2.4) Identification of engine measures for faster light-off Testing of catalyst materials and HEX Optimization of operation strategies for improved CH4-Conversion Demonstration of an exhaust gas aftertreatment system for Euro 6 (WPB2.5) Set-up of CNG engine and vehicle with the exhaust aftertreatment system (transient bench) Optimization of the catalyst heating including cold-start Demonstration of the system performance (Euro 6 legislation) in NEDC on engine test bench Validation of the catalyst activity in a vehicle configuration for Euro 6 compliance (SPA2)

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 5 Reasons for delay: DB2.10 delayed from month 21 to 31: Additional effort necessary for finalizing the 2d HEX bench prototype due to more stringent technical boundary conditions. Lab unit delivered DB2.11 delayed from month 22 to 32: Availability of engine test bench/mechanical engine problems and delayed delivery HEX1/Catalysts DB2.12 delayed from month 24 to 32: Delay in the delivery of raw materials from suppliers. Feed back from current engine tests not available for finalisation of 2d generation of catalyst samples MB2.2 and MB2.3 delayed: Extension of SP duration of 3M SPB2: Deliverables/Milestones

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 6 SPB2: WPB2.2 – General Comments - Compiling mistake occurred during PDF conversion. - Catalyst definition corrected. - Availability of DI-injectors. - At last review meeting the MPI procedure has been presented. - Delay due to availability of DI injectors  extension of project duration required. - Challenging work and delay in delivery of raw materials. - Feed back from engine bench delayed. - 2d Gen of catalysts not available. - Feed back from engine bench about lambda-sweep delayed.

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 7 SPB2: WPB2.2 – Comment 1 In the 24M progress report it is mentioned that the reference catalyst has been improved with incorporation of Pt. The new material demonstrates a better thermal stability and therefore a better THC activity after 40 and 80h ageing. Additionally new catalyst formulations based on Pd/CeO2/Al2O3 and Pd/Al2O3 have been developed at POLIMI and ICS/PAS and exhibit a better CH4 conversion than the reference material at equivalent PGM-loading (6% wt). Moreover the development of a new control strategy based on lambda-sweep allows better conversions for all Pd-based catalysts.

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 8 SPB2: WPB2.2 – Comment 2 There is no fundamental modification of the heat exchanger concept. The counter current flow technology is further developed as described in the DoW. One essential development aspect of the system consists in the cold start strategy where especially the coated zone of the HEX has to be heated up very fast. First studies reported in the 24M PR and in DB2.9 demonstrate that this burner system is not fully suitable for such an application. Therefore a new cold start concept based on a bypass system has been developed taking advantage of the direct flow of hot gases from the engine in the U-turn section. However, if there should be a need for additional energy input during cold start, an electrically heated catalyst (Emicat) can be incorporated in the bypass line.

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 9 WPB2.2 : Advanced Catalyst Development ECOCAT

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 10 SPB2/WPB2.2 – Response to Reviewers’ comments Comment on ”lower efficiency of catalyst prototypes versus reference one”  Reference catalyst has been improved with incorporation of Pt in the Pd-Rh washcoat  New material demonstrates a better thermal stability and better THC activity after 40 and 80 h ageing  New catalyst formulations based on Pd/CeO 2 /Al 2 O 3 and Pd/Al 2 O 3 have been developed by POLIMI and ICSC-PAS  Better methane conversion was exhibited compared to the reference material at equivalent PGM-loading (6-% wt)  A development of a new control strategy based on lambda-sweep allows better conversions for Pd-based catalysts  At 450°C methane conversion was improved from ca. 20 % up to 90 % under lambda sweep (0,98-1,02) compared to the constant feed  Ideal operation point is correlated to temperature and lambda: sligthly rich operation under transient conditions improves CH 4 conversion

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 11 SPB2/WPB2.2 – Response to Reviewers’ comments  Engine results (relative emissions) for the 40 and 80 hours aged Pd-Rh and Pt-Pd-Rh catalysts  A small amount of Platinum has been incorporated in the reference washcoat formulation  Engine tests carried out on a bi-fuel vehicle showed a significant reduction of the deterioration factors for all the measured emissions

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 12 SPB2/WPB2.2 – Response to Reviewers’ comments  Catalytic performance of Puralox supported Pd catalysts (Pd-Al 2 O 3 ) in relation to Ecocat reference sample (after ageing at 600°C and 800°C –GHSV=50000 h -1 )  After most severe treatment, two Puralox ‐ supported catalysts, Pd 6 Puralox (org) and Pd 10 Puralox, show higher activity than the Ecocat reference

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 13 SPB2/WPB2.2 – Response to Reviewers’ comments  Catalytic performance of Pd- CeO 2 --Al 2 O 3 material compared to the Ecocat reference sample (in lean conditions as fresh and after HT-700°C/20h – GHSV= h -1 ) Fresh Aged  Significant performance improvement achieved in respect of the reference at lean conditions

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 14 SPB2/WPB2.2 – Response to Reviewers’ comments  Catalytic performance of Pd-CeO 2 -Al 2 O 3 material compared to the Ecocat reference sample (in λ=1 conditions as fresh and after LS-1030°C/20h aged (LS = lean 10 min + stoichiometric 50 min) – GHSV= h -1 )  At stoichiometric conditions after ageing the new sample has better light off performance; as fresh both the samples (the reference and Pd-CeO 2 -Al 2 O 3 ) have comparable performance FreshAged

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 15 SPB2/WPB2.2 – Response to Reviewers’ comments  Identification of superior and more stable CH 4 conversion performances under -sweep ( ) than under constant feed conditions -sweep Constant feed  Improvement by the operation strategy (reference catalyst)

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 16 SPB2/WPB2.2 – Response to Reviewers’ comments  Ideal operation point is correlated to temperature and lambda  Sligthly rich operation under transient conditions improves CH 4 conversion  Improvement by the operation strategy (reference catalyst)

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 17 SPB2/WPB2.2 – Low cost claimed by Ecocat  Ecocat is involved to do the the up-scaling, coating and the producing of the catalysts for the further tests in laboratory and in engine  In addition, the improvement of the reference catalyst has been a task during the period  Due to the very challenging work to develop an efficient methane catalyst with early light off together with good NOx abatement there have been delays in the materials development which have been postponed the majority of the coating and up-scaling works of the 2 nd generation catalysts to the third year of the project  In addition, no feed-back from the engine test for the 1 st generation samples has been available due to the delays in the engine bench activities in SPA2 and WPB2.4.  The feed-back is needed to guide the catalyst material development for the most efficient way  Therefore, the up-scailing of the 2 nd generation materials and the preparation of the samples to the engine bench testing will be done during the third year of the project  Limited resources have delayed the work in Ecocat

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 18 SPB2/WPB2.2– Updated activities planning  Up-scaling and the coating trials of the new catalyst formulations based on Pd/CeO 2 /Al 2 O 3 and Pd/Al 2 O 3 which have been developed by POLIMI and ICSC-PAS are in progress in Ecocat  Results available on M32 meeting (May 25-26, Finland)  These 2 nd generation samples will be then coated and tested in laboratory scale (real catalysts)  Simultaneously the proto samples will be prepared for the engine tests in AVL/Daimler  Deliverable DB2.12 Catalyst samples Gen.2/new formulations will be created delayed on M32 (originally planned on M28)

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 19 WPB2.3 : Exhaust Heating/Catalyst Concepts USTUTT

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 20 Development of different cold start strategies for coated heat exchanger according to DB2.9 (USTUTT):  Option 1: Cold start burner (section of DB2.9)  Option 2: Cold start burner and/or bypass system (section of DB2.9)  Option 3: EMICAT ® and bypass system (section DB2.9) WPB2.3 Outline referring to reviewer’s comments Reviewer’s comment related to technical issues of WP B2.3: Answer:  Inconsistent numbering due to later.pdf conversion.  Countercurrent hex is still the essential part of our concept!  Challenges and possible solutions for cold start will be described in this presentation.

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 21 Challenges / Drawbacks:  Thermal inertia and countercurrent hex strongly retard heat-up of catalyst section during cold start  Secondary emissions and back pressure sensitivity of fuel burner Solutions:  Reduce material thickness (realized for MK2 prototypes)  Use bypass system and electric heater (EMICAT ® ) instead of cold start burner WPB2.3 Development work  Cold start strategy development (DB2.9)  Lambda-sensitivity of TWC requires additional lambda control of fuel burner  No impact on lambda value if electric heater or bypass is applied Original design:  Challenges / solutions during cold start phase

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 22 WPB2.3 Development work  Cold start strategy development work (DB2.9)  Bypass strategy Normal mode:  Exhaust flows through inflow and outflow channels of hex Bypass mode (test bench only!):  Hex is separated from exhaust flow  Protection of hex in case of engine malfunction Cold start mode:  Hot exhaust enters hex at U-turn and exits through outflow channels.  Cat. light-off temperature can be further reduced with H 2 / CO – rich exhaust Basic idea: Feed hot engine exhaust directly into coated end of heat exchanger  Is the engine exhaust sufficient as heat input?

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 23 Model / Prototype geometric parameters: WPB2.3 Development work  Cold start strategy development work (DB2.9) Parameter MK1 prototypeMK2 prototypeComputer model Total channel height h c 2.9 mm Channel width w c 2x50 mm 100 mm Total cross section m m 2 Number of channels 4x27 53 Metal sheet thickness s m 0.15 mm Thickness fins 0.15 mm0.075 mm0.15 / mm Cells per inch hex / cat 16 / 3030 / 3016 / 30 and 30 / 30 Cell densities hex / cat 133/250 cpsi250/250 cpsi133/250 and 250/250 Overall length L 300 mm Coated length L c 120 mm100 mm120 / 100 mm  Compromise between hex efficiency and pressure drop!

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 24 WPB2.3 Development work  Cold start strategy development work (DB2.9)  Bypass system; simulated network:  Hot gas source as additional support during cold start Cold start mode:  During first 92 seconds of NEDC  Required time period found by optimization  Constant hot gas support Normal mode:  During remaining NEDC  T-controlled hot gas support I/0 Flap as new element  Is the bypass during cold start alone with a state-of-art catalyst heating strategy sufficient ?

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 25 Resulting emission values for methane WPB2.3 Development work  Cold start strategy development work (DB2.9) MK2 prototype EU6 THC emission limit  Significant reduction of THC emissions compared to originally proposed solution  Remaining gap without auxiliary heating could be closed with appropriate engine operation strategies (e.g. „cylinder unbalancing“) Bypass switch time

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 26 WPB2.3 Development work  Cold start strategy development work (DB2.9)  Additional option: EMICAT and bypass system: Cold start mode:  During first 92 seconds of NEDC  T-controlled EMICAT support (analogous to hot gas support)  No additional gas feed required Normal mode:  During remaining NEDC  No further heating support

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 27 Resulting emission values for methane WPB2.3 Development work  Cold start strategy development work (DB2.9) MK2 prototype EU6 THC emission limit Bypass and Emicat switch time  Very short initial energy input is sufficient!

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 28 WPB2.3 Conclusions Simulations underlined importance of thermal inertia during cold start:  MK2 prototype will be significantly lighter due to reduced fin thickness. For efficient cold start, a bypass strategy was developed:  Bypass operation only during cold start (92s)  The Emicat ® system is a very promising amendment to the bypass strategy.  Special engine operation strategies (“unbalanced cylinders”) produce a CO/H2-rich exhaust during cold start and could make additional heating obsolete. In combination with a heat exchanger, only very short operation periods of cold start support required! → Auxiliary heat remains in the system!

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 29 WPB2.4 : Engine Testing/EAT System Management AVL

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 30 SPB2 WPB2.4 – AVL - Answers to Reviewer Comments Comment on “catalyst characterization based on MPI engine not in line with revised DoW and delays”: Characterization on MPI: In the last review meeting it was explained that the catalyst characterization tests can also be done with MPI instead of DI. Comparison measurements have been done to prove that the exhaust gas composition is similar. This work-around was necessary because no sufficiently working DI injectors were available. Waiting for DI components would have caused additional delays. From the technical point of view there is no disadvantage to do the catalyst characterization (at stabilized conditions) with MPI instead of DI. For further investigations regarding catalyst heating after cold start and strategies for fast catalyst light-off for sure DI injectors will be used. These investigations are in progress and are part of the investigations within the next month. Delays: It is right that there are significant delays, therefore AVL recommends an extension of the project duration for 3-6 month. Reason of the delay is the availability of DI injectors as already mentioned several times.

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 31 SPB2 WPB2.4 – AVL - Answers to Reviewer Comments Comparison of exhaust gas composition at Lambda 1, using different operation strategies The diagram below shows the exhaust gas composition range with different operation strategies. With the used configurations (MPI balanced / unbalanced) for TWC characterization the exhaust gas composition is in the same range as it is with direct injection. So the results done with MPI are valid also for DI THC MPI or DI operation / Variation of composition due to unbalancing DI operation / Variation of composition due to homogenization (injection timing) MPI operation / balanced (as used for catalyst characterization step 2 / balanced) MPI operation / unbalanced (as used for catalyst characterization step 2 / unbalanced) CH 4 COO2O2 NOx % % 3% 2% 1% 0 CO, O 2 [%] THC, CH 4, NOx [ppm]

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 32 SPB2 WPB2.4 – AVL – Updated planning See roadmap from Dr. Weibel

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 33 SPB2 WPB2.4 – AVL - Additional technical information Done in the last month:  5 different samples were characterized with the same procedure that allows the comparison of conversion rate for the different formulations  Also the strategy of cylinder unbalancing was tested. As already reported this strategy allows to increase the CO content in the exhaust gas that leads to higher exothermic reaction and so better conversion efficiency  Actually the effect of Lambda oscillation is investigated for the different catalyst formulations and the optimization of the parameters for this oscillation Next Steps:  Characterization of 2 samples with alternative catalyst formulations  Conversion efficiency after ageing of all 7 catalyst formulations Catalyst Characterization

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 34 Peak of conversion reached with rich mixture Exact positioning of conversion peak is temperature and/or engine operating point dependant Improvement of light off through adaption of lambda strategy Further improvement expected with usage of advanced engine operating strategies (cylinder unbalancing) Cat #2a Cat #1 Cat #2a Cat #1 Cat #2a Cat #1 SPB2 WPB2.4 – AVL - Additional technical information

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 35 SPB2 WPB2.4 – AVL - Additional technical information This example of the comparison between balanced an unbalanced cylinders shows the significant increase in conversion efficiency. Also the Lambda range with high conversion is much wider than with balanced cylinders Catalyst Characterization Significantly more exothermic reaction due to CO increase

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 36 SPB2 WPB2.4 – AVL - Additional technical information  Setup and first tests were done  Together with UNI Stuttgart the operation strategy for the different phases can now be defined.  The phases are (similar to conventional catalysts without Heat exchanger)  Phase 1: Catalyst heating – Time before catalyst light-off  Phase 2: Catalyst warm-up – Time from CO light-off to full conversion  Phase 3: Normal operation  Phase 4: Keeping HEX warm in low load phases Heat exchanger (test bed prototype #1) testing: TWC (to compare sizes) Flaps

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 37 Conclusion/Road map SPB2

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 38 SPB2: Summary / Conclusion (24M Meeting) WPB2.2: Advanced catalyst development - Developed mixed oxides are better than systems described in the literature but not alternatives for Pd based catalysts - Novel active Pd based formulations have been indentified and scaled up for real catalytic testing, showing better performances than the reference catalyst - Additional Pt on reference catalyst improved durability - Sulfur poisoning is an issue for the Pd based catalysts, but regeneration is feasible - Operation strategy based on optimal controlling of lambda oscillation and lambda setting provide improvement of catalyst performances - Implementation of the NSC technology on a CNG engine possible. Regeneration of NSC with H2 generated in the rich phase

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 39 WPB2.3: Exhaust heating – Catalyst concepts - Identification of EAT operation strategy on laboratory scale - Cold start strategies identified for efficient HEX heat up - Identification of hex design improvements. Implementation on 2d generation HEX - 1 st generation of laboratory and bench scale HEX successfully manufactured WPB2.4: Engine testing / EAT system management - Baseline testing performed both with DI and MPI - Engine measures for faster lightoff identified - EAT/CH4 catalyst evaluation started – 2 formulations are tested in preconditioned condition. Improvement of light-off through adaption of lambda strategy - HEX system on engine test bed ready for testing SPB2: Summary / Conclusion (24M Meeting)

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 40 SPB2: Road Map Catalyst / HEX testing (24M Meeting) Catalysts tested: Pd/Rh 170 g/ft3 Pd/Rh 200 g/ft3 Pd/Rh 300 g/ft3 Pt/Pd/Rh 200 g/ft3 Catalysts tested: Pd/CeO2 200 g/ft3 Pd/CeO2 300 g/ft3 New formulation ? Catalysts tested: Best formulation

INGAS INtegrated GAS Powertrain INGAS “reviewer meeting”, “Brussels”, “April 2011” 41 SPB2: Road Map Catalyst / HEX testing (New Time Table) Catalysts: Pd/Rh 170 g/ft3 Pd/Rh 200 g/ft3 Pd/Rh 300 g/ft3 Pt/Pd/Rh 200 g/ft3 Catalysts: Pd/Al2O3 300 g/ft3 Pd/CeO2 300 g/ft3 Catalysts: Best formulation Deliverable/MS: New delivery date New time table