Osvaldo José Venturini

Technical and Economic Evaluation of IGCC Systems Using Coal and Petroleum Coke Considering the Brazilian Scenario

The increasing trend in global production of petroleum coke (petcoke) is the result of their multiple and innovative industrial applications. From this point of view and also considering the current situation of the traditional energy reserves worldwide, it is important to conduct studies in this area through analysis of the main components of the power plants utilizing this fuel (petcoke). The main target of this study is to realize a techno-economic evaluation of IGCC (Integrated Gasification Combined Cycle) technology, using Brazilian coal, petcoke and a mix of 50% coal and 50% petcoke as fuel. In this paper, the gasification process and the combined cycle are analyzed, considering the implementation of the IGCC technology in the Termobahia power plant. Termobahia is a cogeneration combined cycle power plant, located in the Brazilian state of Bahia that produces 190 MW of electricity and 350 ton/h of steam. The steam produced is sold to an oil refinery (RLAM) located next to it. In first part of this work, the production of the synthesis gas (syngas) from coal gasification was simulated using CeSFaMBi™ software. In the next part, the syngas produced is used to analyze the power plant performance through GateCycle™ software. Finally, the obtained operational and economic parameters are compared with the actual operational parameters of the Termobahia power plant in terms of costs, fuel substitution and combined cycle performance variables, as net power, global efficiency and heat rate.© 2011 ASME

Relevant Points for Thermodynamic Diagnosis Application Using the Reconciliation Method

After some hours of operation, every power plant’s equipment begins to show degraded performance. The amount of equipment degradation and the gain that can be achieved in plant heat rate and power generation by the replacement or repairing of each component is important information for proper plant maintenance management. This paper aims to show how diagnosis and prognosis of a power plant can be performed based on thermodynamic data measured by plant instrumentation on site. Some important points such as how to increase the accuracy of the prognostic by developing the complete Taylor series and how it affects the thermodynamic state are also explained. Practical considerations for implementing a thermodynamic diagnosis/prognosis system in a real plant are also discussed. The system receives thermodynamic data from the plant information system (PI) and after a filtering step, the performance factors (PFs) of each component are calculated based on the component’s performance curves. Thus, the current state can be modeled using these PFs. By replacing the calculated performance factors, component by component, with factors that represents no degradation, future cycle performance can be estimated. This work is a partial result of an ongoing research program that implements a thermodynamic diagnosis/prognosis system on a 130 MW combined cycle co-generation power plant.Copyright

Aerodynamic Analysis Using CFD for Gas Turbine Combustion Chamber

In the past few years, with the development of advanced numerical computational codes, numerical simulation became a promising option to developing and improving the technology in different fields. The obtained results by simulations are used to get important information during the design phase or optimization of industrial equipment. Its employment generates reliable results at low cost due to the reduced number of experiments as well as the opportunity to develop new products and perform many simulations before its production. However, the numerical simulation credibility can only be verified when compared to the obtained results by experiments. This work aims to present and evaluate different aerodynamics models applied to combustion chambers using a CFD tool. In addition, aerodynamic analysis is made in a model of combustion chamber, where the flow is simulated with successive refining of the mesh as part of its validation process. For it, it is used a Low Nox Emission Combustion Chamber from Floxcom project as reference to validate turbulence models. Once that it is done, the selected turbulence model with satisfactory precision is used to describe the aerodynamic behavior of an annular combustion chamber from velocity and pressure distribution, which are important parameters to set load losses and recirculation intensity, which can affect the complex phenomenon of combustion.Copyright