Barbosa F.C.,FCB Consulting |
Barbosa F.C.,In Land National Transport Agency
SAE Technical Papers | Year: 2012
Environmental concerns related to intensive fossil fuel use have pursued the development of programs to promote the production and use of renewable fuels. This is specially true for diesel fuel used in transit bus fleets, in which the intensive and concentrated use in densely populated areas generates adverse environmental effects in cities all over the world. Although improvements in fossil fuel quality have been achieved in the last decades, most have to be done to make breath cleaner in world metropolis. One of the most promising options, known as Biodiesel, is an ester produced from vegetable oil or animal fat, in a chemical reaction with methanol or ethanol, through a process known as transesterification. It contains, on average, 8% and 12.5% less energy than diesel fuel in a volume and in a weight basis, respectively, which affects engine power, in accordance with the blend used. Biodiesel and, hence, biodiesel blends, as oxygenated fuels, may reduce engine's emissions, like smoke, PM, CO and HC. However, oxygen content also increases NOx emissions, which has to be considered for ozone nonattainment areas. As a biofuel, it degrades with the presence of water, oxygen and elevated temperatures, forming products that can be detrimental to engine components, and also can freeze or become a gel into the injection system at low temperatures, which demands a strict control of its properties, and blend percentages, in accordance with technical standards established by regulatory authorities. Brazil, one of the world leaders in Biodiesel use, with a compulsory program of 5% blend for all the country's diesel fleet, had an annual consumption of 2.5 billion of litters in 2011, 80% of which derived from soybean. Besides the regular 5% blend program, there are some experimental programs with transit bus fleets, ranging from 20% to 100% blends, with a high mileage and technical experience. This knowledge, allied to available capacity of Brazilian biodiesel industry, has enforced technical discussions about standard improvements and the increasing of biodiesel blend use for transit bus fleets in metropolitan areas. Also, the so called "Sugarcane Diesel", obtained from sugarcane thought a "biorefining" process, and used in a 10% blend in diesel engines without any modifications in experimental programs with transit fleets in São Paulo and Rio de Janeiro, has showed PM emission improvements, without any increase in fuel consumption and NOx emissions. This work is supposed to present an overview of biodiesel engine technology and standardization process and some of the results obtained in Brazilian Transit Bus Fleets Experiments, highlighting the possible next steps, into a technical and regulatory perspective. Copyright © 2012 SAE International.
Barbosa F.C.,In Land National Transport Agency |
Dos Reis J.M.,In Land National Transport Agency |
De Souza A.P.M.,In Land National Transport Agency |
Rodrigues A.S.,In Land National Transport Agency
SAE Technical Papers | Year: 2012
Brazilian Freight Rail Sector emerged in the end of 19th century, when the first railways were constructed, under the first known grant system in the country. Later, in the beginning of 20th century, rail system was expanded to support the increasing economical activity related to the agroexportation business, specially coffee crops. This not planned process resulted in a non integrated network, that has undermined the economical feasibility of rail system and bankruptcy of some rail companies. This culminated with the nationalization of 42 private railways into a national company named Rede Ferroviária Federal SA - RFFSA, in 1957, with the objective to recover and improve freight transport to support activities associated to some industrial process, basically mining and related activities and, later, agricultural production for exportation (grains). During eighties, however, economical crisis and the consequent lack of public investments challenged the operational capacity of RFFSA, resulting in its inability to meet demand for rail freight services and the need of heavy public subsidies. This culminated with the privatization of freight rail system into vertical companies, under a regional format corridors. Concessions were awarded between 1996 and 1998, on a price cap model, under a contractual regulatory approach, with production-safety targets. Performance improved greatly in the first years of concession, with great investments in rehabilitation of tracks, rolling stock and facilities. On a regulatory perspective, however, the network arrangement did not lend to a competitive design, since lines were disposed as isolated corridors, with no economical links between them and no regulatory enforcement to stimulate interoperability. In 2002, Agência Nacional de Transportes Terrestres - ANTT, a regulatory agency, was created, with a mission to monitor the companies' compliance with contracts and stimulate the improvement of rail sector. In its initial activities, ANTT has developed a basic regulatory framework, aimed at the fulfillment of contractual obligations. However, to improve competition and increase rail market share in Brazilian transport matrix, much has to be done, but honoring awarded contracts. Under this context, in 2011, ANTT developed a regulatory package, focused on stimulating competition, establishing shippers and companies rights and regulating investments from concessionaires and shippers. Moreover, ANTT is working on contractual tariff revision, which aims the alignment of rail tariffs to the present cost structure of rail sector, in order to transfer to users part of rail sector's some productivity earnings. So, this work is supposed to present a historical view of the evolution of Brazilian freight rail sector, with a critical view of virtues and weakness of concessions, and the efforts of the regulatory agency to improve the sector, while honoring contracts awarded. Copyright © 2012 SAE International.