Estudo do processo de craqueamento termico de frações residuais do petroleo

Abstract

The obligation that petroleum industry has to supply the market demand for light products, although exists a decrease in light oil reserves and the fact that the refining process profitability is represented by the ability to obtain these lighter products. Against this context is necessary the application of crude oil "upgranding" technologies and methodologies development to simulate the phenomena occurring in these processes, in order to evaluate the feed behavior at the unit and based on predictions, set operational politics with the objective to avoid negative impacts in the final products, unit processes and its profitability.Among the "upgranding" technologies are solvent deasphalting, hydrotreating, hydroconversion, visbreaking, delayed coking and others, however, there is a strong preference in using the last two technologies, being the most economical and requires less investment.With the aim to anticipate operational situations was developed a simulator that can predict the light products yields generated at the furnace, at pilot and industrial units of delayed coking and visbreaking, depending on the feed characteristics and conversion, it also calculates the kinetic constants that describes the rate formation of distillates, intermediate (pre-coke stage), and coke. The importance of developing such simulators for this equipment lies that this is the responsible of providing the temperature necessary to achieve the thermal cracking reactions. In the heating process occurs the asphaltene deposition, the coke precursors, which along the unit operation will be deposited on the furnace tubes. In order to control the pressing generated by the coke and the decrease in heat transfer is needed reductions in operating temperature, causing lower conversions. Thus, is important define operational politics that allows good yields, profitability and run lengths the greatest possible.With the obtained results through the simulators, can be known in advanced the unit behavior as operation temperature, drop pressure, wall temperature, conversion, kinetic constants and parameters of Arrhenius equation, which will facilitate the operational analysis of thermal cracking units when is change for example, feed and operational variables .