Thermal–Fluid Optimization of Stack Architecture for Enhanced Efficiency and Emission Control in Incinerator-Fired Heaters

Abstract

In this paper, a novel integration of an incinerator and a fired heater system is proposed to enhance overall heat recovery and emission performance in oil and gas field operations. The hot flue gases from the incinerator are directed beneath the convection section of the fired heater to maximize heat utilization. Effective mixing between the incinerator and heater flue gases at the convection section inlet is critical to achieving uniform temperature distribution and optimal thermal efficiency. Additionally, the stack design must simultaneously satisfy the contrasting draught requirements of the incinerator, which operates under forced draught, and the fired heater, which relies on natural draught. Computational Fluid Dynamics (CFD) simulations were employed to evaluate the flow characteristics, temperature uniformity, and draught performance of the integrated stack system. The initial CFD analysis identified design limitations, prompting geometric modifications to improve gas mixing and flow stability. The optimized configuration demonstrated satisfactory thermal and flow characteristics, ensuring both efficient heat recovery and emission control. Implementing these improvements at the design stage prevented potential operational challenges and significant cost and schedule impacts during plant commissioning.