SAE World Congress is now WCX17: SAE World Congress Experience. WCX17 is a full-sensory event experience that immerses you in the forefront of the automotive and mobility industries. The theme for the 2016 Society of Automotive Engineers (SAE) World Congress and Exhibition is “Powering Possibilities” and Aramco’s strong fuels research and development program is a natural fit for technical sessions. SAE standards are internationally recognized for their role in helping ensure the safety, quality, and effectiveness of products and services across the mobility engineering industry. The more than 10,000 standards in the SAE. Manufacturing Management Program. Standard: AS6500; WIP; Issuing. SAE World Congress TV: Interview with Jim Forlenza. Extruding-Expelling Soybeans and Utilizing the Products at Planetary Outposts. SAE International is a global association committed to being. Its three premiere events include SAE World Congress, SAE Commercial Vehicle Engineering Congress. Ford and GM 10-speed program debuts - Duration: 58. SAE 2. 01. 0 World Congress . The latest in the series was held in Detroit, USA, from 1. April, 2. 01. 0. There were upwards of a dozen sessions focused on vehicle emissions technology, with most of them on diesel emissions. More than 4. 0 papers were presented on the topic. Attendance was up relative to last year, with most sessions having perhaps 1. Of the attendees 8. US, of which 5. 0% were from the Detroit area, with 7% from Europe and 6% from Asia. Original equipment manufacturers (OEMs) represented 2. This review focuses on key developments in diesel emissions control from the conference. Papers can be purchased and downloaded from the SAE website (1). Conference report: 2010 SAE Congress. This year’s SAE Congress, held from April 13-15. An important keynote address by Christopher Laroo of the US EPA discussed progress on a test program looking at dioxin. SAE Collegiate Design Series. Collegiate Design Series Schedule. SAE Clean Snowmobile Challenge. Houghton, Michigan USA. Fort Worth, Texas USA. Attention Young Professionals: the Young Professional Program at SAE World Congress provides the exposure, training, and access to a wealth of opportunities empowering the next generation of mobility engineers to build the. As in previous years, the diesel sessions were opened with a review paper of key developments from 2. Selective Catalytic Reduction Technology. Selective catalytic reduction (SCR) is the leading nitrogen oxides (NOx) emission control technology for both heavy- duty and light- duty diesel applications. The field is advancing rapidly with new developments being reported on catalyst enhancements and system improvements. As engines become more efficient and regulators become more concerned about low- load NOx emissions, better low- temperature SCR system performance will be required. Currently good performance is limited by urea injection issues (evaporation and hydrolysis) at temperatures below 2. Reggie Zhan (Southwest Research Institute, USA) reported on a new mixer that allows urea injections at temperatures as low as 1. Pio Forzatti (Politenica di Milano, Italy) demonstrated that ammonium nitrate (NH4. NO3) injections can substitute for nitrogen dioxide (NO2) to enhance the low- temperature (2. Some results are shown in Figure 1 for an iron- ZSM5 zeolite catalyst. The effect was somewhat more pronounced with a vanadia (V2. O5) catalyst. The reaction mechanisms were described and involve the nitrate oxidising NO to NO2. Fig. 1. Ammonium nitrate can serve as an . Conditions: gas hourly space velocity (GHSV) = 3. Ammonia readily adsorbs on the acidic reaction sites of Fe- zeolite, but much less so on the basic Cu- zeolite sites. This can inhibit the low- temperature performance of Fe- zeolites. On the other hand, NO2 adsorbs on Cu- zeolite reaction sites, inhibiting further NO oxidation. Most interestingly, this behaviour results in better low- temperature transient performance for Fe- zeolites, because the adsorbed ammonia readily reacts with NOx. Conversely, the Cu- zeolite draws ammonia from physical absorption sites instead, and the early reaction can be further inhibited by the suppressed NO oxidation reaction. Generally, low- temperature SCR reactions are controlled by the rate of chemical reaction mechanisms rather than by mass transfer. In that regard, higher catalyst loadings can enhance low- temperature performance. In addition, Takahiko Ido (Ibiden Co Ltd, Japan) showed in his presentation that a strong relationship exists between ammonia adsorption and de. NOx efficiency, which is also tied to zeolite catalyst loading (6). Because most of the stored ammonia resides in the front half of extruded Fe- . However, at higher temperatures, more urea is needed to maintain the performance of the smaller extruded catalyst. Vanadia SCR catalysts are used in Europe and emerging markets. In the US and Japan diesel particulate filters (DPFs) are fitted on all heavy- duty trucks, and vanadia catalysts have durability issues in these applications caused by high- temperature exposure during DPF regeneration. Advances are now reported by David Monroe Chapman (Cristal Global, Saudi Arabia) (7) on vanadia SCR catalysts that have no volatility up to 7. De. NOx performance of the new vanadia SCR catalyst at 2. Gang Guo (Ford Motor Co, USA) reported on their leading de. NOx approach to bring larger personal vehicles into US Tier 2 Bin 5 compliance (8). Fast SCR catalyst light- off is critical, so the Cu- zeolite SCR catalyst is located upstream of the DPF, and urea storage and dosing strategies are very important. The authors showed that with an exhaust gas recirculation (EGR) strategy, the SCR becomes active after about 1. US Federal Test Procedure US- FTP7. In the first 6. 0 seconds or so after light- off, a high dosing rate of urea (urea: NOx ratio of 5: 1) provides 3. NOx than a stoichiometric injection. Ammonia slip can be an issue, so Cu- zeolite SCR catalyst is added to the downstream DPF to capture and utilise the ammonia. Regarding urea storage, injection of 1. Ammonia stored in the entry sections of the SCR catalyst is most critical to performance. Finally, regulators have a concern about dioxin and furan emissions when using Cu- zeolite catalysts. These extremely toxic components can form if chlorine, polyaromatic hydrocarbons (PAHs) and copper catalyst are present together under exhaust conditions. Laroo (US Environmental Protection Agency (EPA)) made a presentation (no SAE paper available) updating the industry on the EPA's test programme to investigate this (9). As shown in Figure 2, there is no evidence that a Cu- zeolite SCR catalyst produces any additional dioxins or furans (expressed in Figure 2 as International Toxic Equivalent (ITEQ) to dioxin). When a pgm catalyst is added to the exhaust system, as is used in practice on the diesel oxidation catalyst (DOC) and catalysed DPF, toxic emissions are expected to be reduced relative to engine- out levels, and the preliminary results show a trend in that direction. Fig. 2. Preliminary results (9) on the US EPA's dioxin emission programme using Cu- zeolite SCR catalysts show no dioxin formation in the SCR catalyst under worst- case conditions (no precious metal, no urea). Current inventory value for dioxin/furan emissions from diesel engines = 8. DOC = diesel oxidation catalyst, DPF = diesel particulate filter (with pgm catalyst coating), DEF = diesel exhaust fluid (i. The de. NOx efficiency is nominally 7. SCR system at . As a result, efforts are focused on improving efficiency while reducing pgm usage. One of the leading concepts is to use the LNT to generate ammonia during the periodic rich regeneration part of the cycle, and then to store and use this ammonia in a downstream SCR catalyst (2). Papers of note from this SAE Congress extend the understanding of this system, and improve upon the performance. Yuuichi Kodama (Komatsu Ltd, Japan) and Victor Wong (Massachusetts Institute of Technology (MIT), USA) showed that increasing flow rate (space velocity up to 8. However, increasing the space velocity by decreasing the length gave no benefits beyond 5. Further, the total system performance was minimally affected by decreasing LNT length. Hypotheses concerning ammonia and NOx reduction kinetics, rich- lean mixing interfaces, and oxygen storage dynamics with length were proposed but not investigated. Other factors impacting ammonia generation are residual oxygen in the rich gas (strong negative impact), and longer rich times (positive impact). The ratio of NO: NOx in the feed gas had little impact. Water- gas shift reformers result in less ammonia production, but improve system low- temperature de. NOx performance. Lifeng Xu et al. The effect is more pronounced with less aggressive LNT rich purges (less rich, shorter duration). In one case with only two purges over a whole certification test cycle, the system removed ~7. NOx with the LNT accounting for most of it (5. SCR performance was attributed to the non- ammonia species. The leading hypothesis is that organo- nitrogen compounds, which may include isocyanic acid (HNCO), form during the rich purge, and are captured and utilised by the downstream SCR catalyst. The researchers showed that a low- pgm LNT + SCR system (3 g l. Cu- zeolite performs better than Fe- zeolite. Interestingly, they looked at a variety of LNT and SCR configurations (in series or alternating), and concluded that the series arrangement is best due to faster LNT light- off. On a vehicle, the system achieves ~9. NOx efficiency for a system roughly the same size as an SCR- only system. In another paper Joseph R. Theis (Ford Motor Co, USA) investigated the ageing properties of the LNT + SCR system (1. With constant LNT management, the SCR advantage decreases if the LNT is aged for 4. The effect is attributed to pgm ageing on the LNT and less efficient ammonia production. Longer rich periods as the system ages can counteract these impacts. During LNT desulfation, the SCR effectively oxidises hydrogen sulfide (H2. S) and carbonyl sulfide (COS) to sulfur dioxide (SO2). Hai- Ying Chen (Johnson Matthey Inc, USA) reported on further optimisation of both the LNT and the SCR using NOx adsorber catalysts (NACs) (1. The LNT was improved by decreasing the oxygen storage capacity (OSC) and replacing 2. NAC with palladium. The results are shown in Figure 3. The lower OSC allows more ammonia to be produced at higher temperatures without as much oxidation. The palladium promotes the NOx reduction function. The Cu- zeolite in the SCR catalyst was improved by adjusting the support material. It better withstands rich- lean cycling, wherein hydrocarbons are adsorbed in the rich period and then oxidise in the lean period, creating damaging exotherms. Fig. 3. The ammonia producing capability of a lean NOx trap (LNT) was improved by optimising the oxygen storage capacity (OSC) and pgm content. About 3% of the global warming potential of the exhaust comes from the N2. O emitted by the LNT during the rich period. Another 2. 4% is attributed to the fuel that is dosed to make a rich purge gas. The balance, 9. 4. Diesel Particulate Filters. Although DPFs have been in commercial production for original equipment manufacturer (OEM) application for more than ten years, there is still much optimisation activity in the field. Papers on DPF regeneration dominated this part of the SAE Congress, with new understanding on current and new regeneration methods being gained. James R. Warner (Ford Motor Co, USA) investigated current DPF regeneration dynamics (1.
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