SIMULATION OF PULVERIZED COAL INJECTION IN A BLAST FURNACE

ABSTRACT A three-dimensional multiphase CFD model using an Eulerian approach is developed to simulate the process of pulverized coal injection into a blast furnace. The model provides the detailed fields of fluid flow velocity, temperatures, and compositions, as well as coal mass distributions during the devolatilization and combustion of the coal. This paper focuses on coal devolatilization and combustion in the space before entering the raceway of the blast furnace. Parametric studies have been conducted to investigate the effect of coal properties and injection operations

PREDICTION OF RACEWAYS IN A BLAST FURNACE

ABSTRACT In a blast furnace, preheated air and fuel (gas, oil or pulverized coal) are often injected into the lower part of the furnace through tuyeres, forming a raceway in which the injected fuel and some of the coke descending from the top of the furnace are combusted and gasified. The shape and size of the raceway greatly affect the combustion of the coke and the injected fuel in the blast furnace. In this paper, a three-dimensional (3-D) computational fluid dynamics (CFD) model is developed to investigate the raceway evolution. The furnace geometry and operating conditions are based on the Mittal Steel IH7 blast furnace. The effects of Tuyere velocity, coke particle size and burden properties are computed. It is found that the raceway depth increases with an increase in the tuyere velocity and a decrease in the coke particle size in the active coke zone. The CFD results are validated using experimental correlations and actual observations. The computational results provide useful insight into the raceway formation and the factors that influence its size and shape

COMPUTATIONAL FLUID DYNAMICS BASED INVESTIGATION OF SENSITIVITY OF FURNACE OPERATIONAL CONDITIONS TO BURNER FLOW CONTROLS

This is the extended second Semiannual Technical Report for DOE Cooperative Agreement No: DE-FC26-02NT41580. The goal of this project is to systematically assess the sensitivity of furnace operational conditions to burner air and fuel flows in coal fired utility boilers. Our approach is to utilize existing baseline furnace models that have been constructed using Reaction Engineering International's (REI) computational fluid dynamics (CFD) software. Using CFD analyses provides the ability to carry out a carefully controlled virtual experiment to characterize the sensitivity of NOx emissions, unburned carbon (UBC), furnace exit CO (FECO), furnace exit temperature (FEGT), and waterwall deposition to burner flow controls. The Electric Power Research Institute (EPRI) is providing co-funding for this program, and instrument and controls experts from EPRI's Instrument and Controls (I&C) Center are active participants in this project. This program contains multiple tasks and good progress is being made on all fronts

A COMPUTATIONAL WORKBENCH ENVIRONMENT FOR VIRTUAL POWER PLANT SIMULATION

This is the tenth Quarterly Technical Report for DOE Cooperative Agreement No: DE-FC26-00NT41047. The goal of the project is to develop and demonstrate a computational workbench for simulating the performance of Vision 21 Power Plant Systems. Within the last quarter, good progress has been made on all aspects of the project. Calculations for a full Vision 21 plant configuration have been performed for two gasifier types. An improved process model for simulating entrained flow gasifiers has been implemented into the workbench. Model development has focused on: a pre-processor module to compute global gasification parameters from standard fuel properties and intrinsic rate information; a membrane based water gas shift; and reactors to oxidize fuel cell exhaust gas. The data visualization capabilities of the workbench have been extended by implementing the VTK visualization software that supports advanced visualization methods, including inexpensive Virtual Reality techniques. The ease-of-use, functionality and plug-and-play features of the workbench were highlighted through demonstrations of the workbench at a DOE sponsored coal utilization conference. A white paper has been completed that contains recommendations on the use of component architectures, model interface protocols and software frameworks for developing a Vision 21 plant simulator

A COMPUTATIONAL WORKBENCH ENVIRONMENT FOR VIRTUAL POWER PLANT SIMULATION

This is the eighth Quarterly Technical Report for DOE Cooperative Agreement No: DE-FC26-00NT41047. The goal of the project is to develop and demonstrate a computational workbench for simulating the performance of Vision 21 Power Plant Systems. Within the last quarter, good progress has been made on all aspects of the project. Calculations for a full Vision 21 plant configuration have been performed for two coal types and two gasifier types. Good agreement with DOE computed values has been obtained for the Vision 21 configuration under ''baseline'' conditions. Additional model verification has been performed for the flowing slag model that has been implemented into the CFD based gasifier model. Comparisons for the slag, wall and syngas conditions predicted by our model versus values from predictive models that have been published by other researchers show good agreement. The software infrastructure of the Vision 21 workbench has been modified to use a recently released, upgraded version of SCIRun

A COMPUTATIONAL WORKBENCH ENVIRONMENT FOR VIRTUAL POWER PLANT SIMULATION

This is the fourteenth Quarterly Technical Report for DOE Cooperative Agreement No: DE-FC26-00NT41047. The goal of the project is to develop and demonstrate a Virtual Engineering-based framework for simulating the performance of Advanced Power Systems. Within the last quarter, good progress has been made on all aspects of the project. Software development efforts have focused primarily on completing a prototype detachable user interface for the framework and on integrating Carnegie Mellon Universities IECM model core with the computational engine. In addition to this work, progress has been made on several other development and modeling tasks for the program. These include: (1) improvements to the infrastructure code of the computational engine, (2) enhancements to the model interfacing specifications, (3) additional development to increase the robustness of all framework components, (4) enhanced coupling of the computational and visualization engine components, (5) a series of detailed simulations studying the effects of gasifier inlet conditions on the heat flux to the gasifier injector, and (6) detailed plans for implementing models for mercury capture for both warm and cold gas cleanup have been created