Navegando por Assunto "Diesel"

Agora exibindo 1 - 2 de 2

Acesso aberto (Open Access)
Análise técnico-econômica da substituição parcial do combustível diesel pelo gás natural em motores marítimos na região amazônica
(Universidade Federal do Pará, 2007-12-07) FRANCO, Alcides Canêjo Linhares; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
The international experience indicates the existence of five main elements related to the expansion of the natural gas consumption as following: a) availability of natural gas reserve; b) restriction offers of other energy ones (especially for the electricity generation); c) concern with the environment by a environmental legislation more rigorous, each day; d) the investments attraction by the private companies permission for the distribution and commercialization of the natural gas; e) the generalized permission for the industry, attracting private companies, because of the opportunity of the investment. In this scene, the construction of the gas line Coari (extraction base) Urucu-Manaus with about 670 kilometers of total extension that will be ready on April of 2008, as divulged by Petrobras on 05/21/2007 and will carry 4.7 million cubic meters per day of natural gas in the first phase of operation. The foreseen total investment is of R$2.4 billions. The natural gas will substitute the diesel and the combustible oil used, mainly, in the production of great part of the consumed electric energy in the Amazon State. It will be used also in the industrial and commercial processes, as well as supplying, with safety, auto-machine vehicles (automobiles, pickups, light trucks, bus). This last application stimulated this research, that establish a technical-economic analysis of the partial substitution of the fuel diesel by the natural gas in maritime engines in the Amazon Region, because the boats are vehicles that cross the rivers of this Region and are used for load and passengers transportation. First, it is demonstrated that it is possible, in technical conditions, the conversion of the diesel engines to consume the diesel mixed with natural gas to the taxes of substitution of diesel for natural gas from 5% to 90%, using available technologies that are in the Brazilian market, under the view of energy and environment performances. Later it presents an economic analysis of the conversion, considering the reservoirs for natural gas compressed - NGC offered in the national market and the kits of conversion. The research reveals: a) the economic viability of the enterprise if the weights and the volumes of the natural gas reservoirs are neglected, especially the first one; b) the no economic viability, considering the transport of the reservoirs, in the boats, that had no financial results because of the prices of the taxes resulting of the space occupied by the volumes and the weights of these reservoirs.
Acesso aberto (Open Access)
Propriedades termodinâmicas de propanóis na fase gasosa via DFT
(Universidade Federal do Pará, 2021-05-03) LOPES, Franklin dos Santos; CHAVES NETO, Antônio Maia de Jesus; http://lattes.cnpq.br/3507474637884699
The main objective of this study is to evaluate the effect of the thermodynamic properties of propanols propan-1-ol, propan-2-ol and their isomers 2- methylpropan-1-ol and 2-methylpropan-2-ol in addition to elaborating a proposal for mixtures with fuels, gasoline, diesel, and kerosene-based on the Functional Density Theory to determine thermodynamic properties, such as specific molar heat at constant pressure, entropy, Gibbs free energy, a variation of the formation enthalpy for calculating the heat of combustion. The excited state of the propanols and their isomers, applied to their energy figures transferred by the functional hybrid of the B3LYP structures, in the bases 6–311 ++ g (d, p) and 6-31g (d) were simulated using the software package Gaussian 09W and the semi-empirical method PM3. To obtain the physical properties of the chemical reactivity in the gas phase of each component and its combustible isomers, the temperature range of 0.5K - 1500K was used at a constant pressure of 1atm and in a vacuum. The addition of propane and its isomers in the combustion phase provided a greater energy balance as a whole, with 2-methylpropan-1-ol and 2-methylpropan-2-ol generating 13.38 and 13.88 KJ / ga more of gain energy per unit mass than ethanol (22.73 KJ / g) and methanol (12.70 KJ / g), the progressive increase of fractions 10%, demonstrates that propan-1-ol with 33.49 KJ / g and propan-2-ol 33.53 KJ / g, obtained the highest energy losses when compared to gasoline, which reached 13.81 and 13.77 KJ / g respectively in pressures, temperature patterns. TheX combustion of propan-1-ol was the lowest in all events over fractions in the case of diesel fuel 11.31 KJ / g and kerosene 12.71 KJ / g.