Temperature balancing in steam methane reforming furnace via an integrated CFD/data-based optimization approach. (2nd September 2017)

• Record Type: Journal Article
• Authors: Tran, Anh; Aguirre, Andres; Crose, Marquis; Durand, Helen; Christofides, Panagiotis D.
• Is Part Of: Computers & chemical engineering. Volume 104(2017)
• Page Start: 185
• Page End: 200
• Publication Date: 2017-09-02
• Subjects: Methane reforming -- Furnace-balancing -- Process operation -- Process optimization -- Data-based modeling -- Valve defects; Chemical engineering -- Data processing -- Periodicals; 660.0285
• DOI: 10.1016/j.compchemeng.2017.04.013
• Languages: English
• ISSNs: 0098-1354

Abstract

Abstract : Highlights: Computational fluid dynamics modeling of steam methane reforming furnace. Hybrid data-based and geometry/physics-based model identification. Optimization-based furnace balancing using data-based and CFD-based models. Substantial reduction of temperature non-uniformity in the furnace and handling of faulty burners. Abstract: In this work, we introduce a furnace-balancing scheme that generates an optimal furnace-side feed distribution that has the potential to improve the thermal efficiency of a reformer. The furnace-balancing scheme is composed of four major components: data generation, model identification, a model-based furnace-balancing optimizer and a termination checker. Initially, a computational fluid dynamics (CFD) model of an industrial-scale reformer, developed in our previous work, is used for the data generation as the model has been confirmed to simulate the typical transport and chemical reaction phenomena observed during reformer operation, and the CFD simulation data is in good agreement with various sources in literature. Then, we propose a model identification process in which the algorithm is formulated based on the least squares regression method, basic knowledge of radiative heat transfer and the existing furnace-side flow pattern. Subsequently, we propose a model-based furnace-balancing optimizer that is formulated as an optimization problem within which the valve position distribution is the decision variable, and minimizing the sum of the weighted squared deviations of the outer reforming tube wall temperatures from a set-point value for all reforming tubes with a penalty term on the deviation of the valve positions from their fully open positions is the objective function. CFD simulation results provide evidence that the optimized furnace-side feed distribution created by the furnace-balancing scheme can reduce the severity of nonuniformity in the spatial distribution of furnace-side temperature in the combustion chamber even when the reformer is under the influence of common valve-related disturbances.