Refinery Options Available to Meet Increased Octane and Volume Demand With Stringent Specifications

Transcription

1 A Monthly Publication by Asian Clean Fuels Association Refinery Options Available to Meet Increased Octane and Volume Demand With Stringent Specifications Today s refiners are faced with an octane deficit generated by lead removal and the increased octane demand to improve vehicle efficiency and lower gasoline sulphur. Continuously stricter emission regulations; increased petrol demand; and, together with policy makers and automakers, they also strive toward improved local energy security. INSIDE THIS ISSUE Vol. 4 Issue 8 - Nov/Dec 2006 Refinery Options Available to Meet Increased Octane and Volume Demand With Stringent Specifications Expert Talk: Interview with Yasunori Takei, Japan Automobile Manufacturers Association (JAMA) Clean Fuels Development in Asia India Rescinds Ethanol Blend Programme Many options are available to meet one or more of these drivers. Refiners can invest in technical operating solutions like catalytic reforming, isomerization, fluid catalytic cracking, alkylation and hydrotreating. They can produce or import high-octane petrol components like ethanol, MTBE, TAME, TAEE and ETBE. Or they can utilise octane-enhancing metallic additives like MMT or Fe. Refinery expansions to increase production are usually costly and time-consuming. As a technical and economic alternative to making operating changes or expending capital to add needed capacity, refiners can also look to produce or import high-octane petrol components. Adding oxygenates to petrol allows refiners to produce petrol without lead and other metallic additives. With oxygenates, refiners can produce cleaner fuels, with improved combustion characteristics and lower olefins and aromatics, to meet stricter emission standards. In this way refiners can also help expand supply diversity and, in the case of ethanol and ETBE, support the local agriculture sector and the request for increased use of renewables. These incremental demands for improvements in petrol quality, volume and supply diversification will continue to place a growing emphasis of the use of locally produced renewable around the globe. ACFA has decided to systematically analyse the different clean fuels refinery solutions available in future issues. In this issue, ACFA includes an overview of the different ways ethanol currently is being utilised as a blending component with petrol. ETHANOL BLENDS Ethanol is a high-octane oxygenate that today typically is being produced from renewable sources such as corn or sugar crops. Surprisingly, numerous studies (refer to figure 1, p4) highlight the lack of energy and production cost-efficiency of utilizing corn ethanol. In one study, industry expert Tad Patzek concludes that the cumulative energy consumed in corn farming and ethanol production is six times greater than what the end product provides your car engine in terms of power. Anhydrous ethanol (ethanol without water) can be blended with petrol in varying quantities. Splash or inline blending of ethanol is generally completed at either 5 vol % or 10 vol %. (Continued on p4) Chemical Properties of MTBE, ETBE, TAME and Ethanol MTBE ETBE TAME Ethanol Molecular Weight (g/mol) Boiling Point (ºC) Vapour Pressure (kpa) Density (g/l) Octane Number Neat Solubility (g/100g H 2 0) miscible You can reach us at acfanews@acfa.org.sg. Visit our website at Copyright Asian Clean Fuels Association.

2 Yasunori Takei has been with Toyota Motor Corporation since 1982 working in the fuel and lubricant area. Currently, he is mainly in charge of fuel research. Mr. Takei is a member of the Fuels and Lubricants (F&L) Committee of the Japan Automobile Manufacturers Association (JAMA) and chairman of the Petrol Yasunori Takei Subcommittee, as well as a leader of the Global Communication Group and LPG Working Group under the F&L Committee. He also is a member of the Asia SAE F&L Steering Committee and a leader of the Fuel Working Group. Mr. Takei played a key role in JAMA s involvement in the publication of the 4th edition of the World-Wide Fuel Charter (WWFC). JAMA, a non-profit trade association for Japanese car, truck, bus and motorcycle manufacturers, currently has 14 members (Nissan, Honda, Hino, Mazda, Suzuki, Toyota, Mitsubishi, Kawasaki, UD, Daihatsu, Fuji, Isuzu, Yamaha and Fuso) and maintains offices in Asia, Europe and the US. To learn more about how the automobile industry and Toyota are viewing the current and future fuel and engine system, ACFA News is pleased to have Mr. Takei share his views. Q1: Can you tell us briefly what changes have been made in the 4th edition of the WWFC? The main revision is the realignment of categories. The sulphur and emission standards are reviewed due to the recent progress of engine and emission control technologies. Review of miscellaneous specification limits and updates of test methods were done. Much data and photos are added as evidence of the fuel impacts. Q2: Fuel qualities in Asian countries differ widely due to varying progress on development. Some countries are still using leaded petrol whereas other countries like Japan, Hong Kong, South Korea and Taiwan have implemented very strict fuel quality and emission standards. Does this situation pose a concern for JAMA? EXPERT TALK Interview with Yasunori Takei of Japan Automobile Manufacturer s Association WWFC 4TH EDITION NOW AVAILABLE You can get a copy from the following associations or their websites: Alliance ACEA EMA JAMA JAMA has a strong interest for harmonization of emission regulations and fuel quality in Asia. ASEAN Automobile Federation (AAF) has proposed the implementation of Euro II emission regulations and Euro II fuels by 2007 and Euro IV emission regulations and Euro IV fuels by 2012 to the governments in ASEAN countries. We already have Euro IV technologies and can introduce these technologies into the market if the fuel quality standards are met. JAMA strongly supports AAF s position. It will provide huge benefits for people living in Asia by promoting improved air quality in Asian countries as well as contributing to the developments in the auto and parts industries in Asia. Q3: Advancements in vehicle emissions control technology need to be coupled with better fuel quality. In what ways does fuel quality affect vehicle performance and emissions reduction efficiency? For petrol systems, the key is how to maximize the performance of after-treatment systems. The important parameters are the airfuel ratio control and the performance of the catalyst itself. The three-way catalyst can purify HC, CO and NO x at the same time with stoichiometric condition of the air-fuel ratio. The distillation properties like T50 and deposits in the intake systems are key properties for the air-fuel ratio management. It is important to control distillation properties to appropriate levels and to use adequate detergent additives to prevent deposits. For the catalyst performance, sulphur and metals are key issues. Sulphur in petrol can easily poison the catalyst and deteriorate the conversion efficiency. Lowering sulphur is essential to achieving stringent emission regulations. Metals like lead, manganese and ferrocene cause serious damage not only to the catalysts but also to the spark plugs and oxygen sensors, and, as a result, affect not only exhaust emissions but also fuel economy and driveabilty. The actual market experience related to metals is described in the WWFC 4th edition. Furthermore, some researchers have reported health effects by manganese recently. For diesel, EGR and oxidation catalyst are typical systems for Euro II emission regulations. For Euro IV, cooled EGR and DPF will be adopted. Sulphur is a key property for those systems. With higher sulphur fuels than the regulatory requirement, engine durability will be lowered. The effects on emissions will also be serious. In some cases, exhaust emissions may be higher than without the catalyst. Q4: Sulphur is viewed as the new lead and most countries are doubling their effort in reducing sulphur from petrol and diesel. Can you elaborate why and what level of sulphur is ideal? (Continued on p3) November/December 2006 Page 2

3 EXPERT TALK Interview with Yasunori Takei of Japan Automobile Manufacturer s Association (continued from p2) Sulphur is a key property for the emission reductions from both petrol and diesel engines. Sulphur poisons the catalysts and then deteriorates the conversion efficiency. From the viewpoint of emission reduction, lower sulphur provides better emissions. We strongly recommend the WWFC as a suitable sulphur level for the required emission levels: Em. Stds Cat 1 Cat 2 Cat 3 Cat 4 Tier 0, Euro I Tier 1, Euro II or III U.S./Cal LEV or ULEV, Euro III, JP 2005 Tier 2, Cal LEV II, Euro IV, HD U.S. 2007/10, non-road Tier 4, Euro V Sulphur (ppm) Petrol 1, Diesel fuel 2,000 * Note: *1) 3,000 ppm is allowed as a transitional limit. Q5: Beside sulphur, what other properties of petrol and diesel are important to ensure that the automobile is operating efficiently and tailpipe emission is minimized? What can you tell us about the position of JAMA with regard to metallic additives? For petrol three-way systems, air-fuel ratio management is the other key technology to control emissions at low level. Adequate distillation properties and deposit control in the intake systems (use of adequate detergents) are very important for the air-fuel ratio control. For diesel systems, distillation properties (90% distillation temperature/t90) and lubricity will be important properties. The former has major effects on emissions and the latter closely relates to the durability of Fuel Injection Equipment (FIE) systems. Impurities like water, sediments and particulates are also very critical properties for the durability of fuel supply systems and injector deposit formation in both petrol and diesel vehicles. Good housekeeping in fuel distribution systems is essential to minimize the impurities. JAMA never recommends metallic additives in petrol or diesel fuels. Our experience in the real market is described in the 4th edition of WWFC. Q6: According to the WWFC, oxygenates (ethers and alcohols) are added to petrol to increase octane, extend petrol supply, reduce vehicle emission (tailpipe and evapourative) and improve engine performance and/or durability. When oxygenates are used, why are ethers preferred? Bioethanol is an important alternative fuel. However, ethanol easily absorbs moisture and increases vapour pressure as it is blended in petrol. In some cases, material compatibility is an issue. When ethanol-blended petrol is introduced into the market, adequate specification of the ethanol and its blends, good housekeeping to prevent contamination, fuel quality monitoring systems to control fuel quality at the pump, and countermeasures like pump labels are recommended. On the other hand, the characteristics of ethers are more similar to that of petrol. So we expect less of an issue in vehicle performance as ethers are blended into petrol. Some people may point out that MTBE was prohibited in some states in the US. But that is an issue of the fuel distribution systems. Petrol consists of more than 200 chemicals and contains certain toxics like benzene and xylene. It is also reported that ethanol carries chemicals into underground water and diffuses those chemicals quickly and widely. The important thing is risk management in the fuel distribution systems to prevent the leakage of fuels to the atmosphere or groundwater. Q7: Diesel vehicles are often viewed as highly polluting compared to petrol vehicles but they are used extensively in many Asian countries, especially for heavy vehicles and for public transportation. What new technologies are being developed by the automobile industry to reduce emissions from diesel vehicles and how will they affect diesel fuel quality? To realize petrol level of emissions, Euro IV level of diesel technologies will be necessary at the least. That system is typically Turbo Intercooler CR-DI engine with Cooled EGR to reduce NO x and DPF for reducing particulate matter in exhaust gases. As for fuel quality, sulphur free or less than 50 ppm at least is essential in order for this system to meet the petrol level of emissions. It is also important for the durability of FIE to improve lubricity and to prevent the contamination of impurities like water and particulate. Metals in fuels promote injector deposits and will affect the life of DPF. Metals including metal additive and/or sulfated ash should be minimized. Q8: What role do biofuels play in the WWFC? What studies are the committee currently working on in regard to the use of biofuels? Is the WWFC committee planning to introduce specifications for alternative fuels and biofuels? Biofuels are important as alternative fuels for CO 2 reduction and energy security. Members of the WWFC steering committee have great interest in learning more about these fuels. November/December 2006 Page 3

4 Refinery Options Available to Meet Increased Octane and Volume Demand With Stringent Specifications (continued from p1) In general, the car manufacturers approve the use of up to 5 vol % ethanol while some car manufacturers also accept blends up to 10 vol % for their newer models (refer to World-Wide Fuel Charter). For blends with more than 10 vol % of ethanol, engine modifications are required (refer to figure 2). Figure 1 Splash blending of ethanol presents challenges to the refiners like pipeline fungibility and increased Reid Vapour Pressure (RVP). Whereas ethanol is completely miscible in petrol, the presence of small amounts of water will rapidly lead to phase separation, i.e. ethanol will be absorbed by any water present in the system. This can result in poor vehicle performance and possibly engine damage. The actual phase separation conditions are a function of ethanol content, temperature and properties of the petrol phase, but the effect is particularly marked at low ethanol concentrations. Therefore, only anhydrous ethanol should be considered for blending in petrol. As there typically is a small amount of water in finished petrol, the ethanol also has to be transported separately, in new logistic systems, from petrol. Blends of ethanol and petrol also result in a disproportionate increase in the vapour pressure of the finished petrol. Higher petrol vapour pressure can also cause drivability problems in vehicles. As a consequence, the base petrol must be tailored to recognize the volatility increase that ethanol addition will produce in the finished blend. The changes necessary to the petrol include the replacement of relatively expensive ethanol with the most economical and readily available butane stream. E-85 E85, a mixture of 85% ethanol and 15% petrol, has recently been receiving heightened marketing attention by some global vehicle manufacturers. It seems their preferred way, over pure ethanol, Figure 2 Source: U.S. Department of Agriculture, July to support the strong local policy drive towards ethanol and improved energy independency. The use of E85 requires special alternative fuel vehicles, a flex fuel vehicle (FFV) and a new logistic system for the refined products. An FFV is capable of running on either petrol or a high-content ethanol blend. In addition, the vehicle can operate on any intermediate blend of the two fuels, giving the consumer the option of filling with either fuel depending on their availability and price. It is determined that E85 will cost consumers more money especially due to its 20-30% lower energy content. Local financial support, both for purchase of vehicle and fuel, is required to enable E85 to enter the market. In the October 2006 Consumer Report, it was determined that E85 will cost consumers more money especially due to its 20-30% lower fuel economy than petrol blends due to ethanol s lower energy content. Because of this fuel mileage loss, drivers would need to pay proportionally less at the pump to encourage use of E85. ETHERIFICATION Renewable ethanol can also be utilised for the production of ethyl tertiary butyl ether (ETBE). ETBE is about 42% ethanol and is produced by processing renewable ethanol with a natural gas-based liquid known as isobutylene. Global auto manufacturers and refiners prefer this way in case they are required to utilize renewable fuels (refer to World Wide Fuel Charter). ETBE, as MTBE, improves emissions immediately and no changes to the refining, pipeline and distribution operation or automotive technology are required. Unlike ethanol, ETBE can be blended into the final petrol right in the refinery and (Continued on p6) November/December 2006 Page 4

5 Clean Fuels Development in Asia ACFA promotes the use of cleaner transportation fuels based on four important attributes: 1) use of sound science and facts to support decision-makers; 2) cost effectiveness and viability to support widespread use; 3) environmental improvement and protection; and 4) promotion of available safe technologies. To help advance this mission, ACFA s executive director, Clarence Woo, recently spoke at two international conferences about the importance, development and benefits of clean fuels in the Asian region. His talks in both cases were very well received and helped to advance the organisation s mission of clean air through clean fuels. Mr. Woo spoke at the 9th IMPCA Asian Methanol Conference held earlier in 2006 in Singapore. His talk, Clean Fuels Development in Asia, explained the need for improved fuel quality in the region to help reduce vehicle emissions that cause serious health impacts from air pollution. One complicating factor in the region is different vehicle characteristics extensive use of two-stroke engines, for example compared to more industrialized countries. He noted demands on future fuels in Asia, including: Completing lead phase-out; Progressive sulphur level reductions; Benzene, aromatics and olefins reductions; Use of non-lead metallic additives; and Expanded use of oxygenates & biofuels. While there are challenges for clean fuels refinery upgrading needed; changes in distribution systems and product handling; vehicle improvements Mr. Woo stated that effective options are readily available, especially the use of oxygenates like MTBE. He presented the benefits of MTBE and other oxygenates to improve petrol quality and reduce vehicle emissions immediately when used. He highlighted recent successes in outreach and educational efforts on clean air through clean fuels. Mr. Woo also spoke in October at the 4th Annual Methanol Forum held in Houston (US). His speech, MTBE Trends in Asia, addressed a similar theme about clean fuels developments in the region. He also focused on the association and the industry s commitment to Responsible Care in product management. He noted current support to ensure proper petrol tank management. India Rescinds Ethanol Blend Programme The Indian government has backed away from a 5% ethanol blended petrol programme, originally to have taken effect this November. The Petroleum Ministry argued that since there are competing demands on ethanol supply such as chemical industries and potable alcohol prices of ethanol would rise dramatically if the programme was made mandatory. Instead, the PSU oil firms will be given freedom to protect their commercial interests at arriving at a viable ethanol pricing. The government had previously decided to push ahead with the mandatory programme; however, changed when realizing that the volume required could not be supplied by the domestic industry. The Petroleum Ministry is proceeding to allow oil firms to acquire sugar and ethanol assets outside the country, along the same lines as equity oil. The government is also considering lowering the import duty on alcohol to 7.5% and possibly waiving all or part of the excise duties proportional to the ethanol volume blended in petrol. The Agriculture Ministry is working to safeguard the interests of domestic farmers it plans to give huge incentives for alcohol production made from food grains. November/December 2006 Page 5

6 Scientists Issue Declaration to Prevent Health Effects from Metals Human exposure to dangerous heavy metals like lead and manganese has long been recognised to cause serious health effects. During the summer of 2006, scientists from 27 nations convened an International Workshop on Neurotoxic Metals: Lead, Mercury and Manganese, in Brescia, Italy. Data were presented on environmental sources and distribution; human exposure; health effects, focused on neurotoxicity or effects to the nervous system; risk assessment and prospects for prevention. The outcome of the symposia was The Declaration of Brescia on Prevention of the Neurotoxicity of Metals. Initial recognition of neurotoxic effects from metals occurred in high-exposure conditions lead poisoning in smelter workers and manganese poisoning in miners. As better investigative methods, analytical tools and diagnostic understanding are developed, effects at much lower exposure levels became recognised; the extent of toxicity was much greater than initially known and the size of the affected population much larger. Unfortunately, early warnings were frequently ignored and often resisted. Despite this knowledge, even today, gasoline containing heavy metal additives continues to be used in some parts of the world. Refinery Options Available to Meet Increased Octane and Volume Demand With Stringent Specifications (continued from p4) then be shipped to its point of sale through the traditional transportation pipeline. ETBE extends petrol supply, provides octane, improved combustion and enhances vehicle performance. It is a more economical way to use ethanol as it reduces volatility and allows refiners to continue using readily available butanes. Figure 3 Figure 4 The workshop resulted in a series of recommendations on developing effective strategies, prevention of neurotoxicity of metals, and future research directions. Some of these recommendations include: Intensified attention must be paid to early warnings of neurotoxicity; Tetraalkyllead must be eliminated without delay from the gasoline supplies of all nations; Current exposure standards for lead need to be reduced urgently, especially for children; Exposures of pregnant women and young children to manganese need to be reduced; Addition of organic manganese compounds to gasoline should be halted immediately in all nations; and Exposure standards for manganese need to be reconsidered. The workshop scientists reinforced the importance of further research on the exposure and health effects of metals. In Europe, ETBE is the preferred way by both refiners and vehicle manufacturers to use ethanol. Bioethers are key tools to enable bioethanol market penetration and the EU biofuel directive fulfillment. Many MTBE units have today been converted to allow the use of either MTBE or ETBE dependent on their tax situation and raw material availability. If you have any enquiries or feedback on ACFANews, please contact us at acfanews@acfa.org.sg or contact Lee Chook Khean at or cklee@acfa.org.sg. Visit our website at November/December 2006 Page 6