Assessment of optimum slurry pipe design for minimum erosion

Abstract

Particulate erosion in the slurry handling unit of a thermal power plant is a major concern. Pipe bends are the most erosion-affected elements of a pipeline unit; hence, adopting a cost-effective method to reduce pipeline erosion is a necessity. This work aims to propose an optimal pipe bend design to minimize particulate erosion by analyzing the erosive wear of geometrically different pipe bends for bottom ash slurry flow using computational fluid dynamics code, i.e., FLUENT. A three-dimensional simulation study of erosive wear was carried out by applying Euler-Lagrange modeling along with the standard k - ε turbulence model to solve the complex multi-phase flow. Pipe bends with different bending angles (30°, 45°, 60°, and 90°), diameters (50 to 250 mm), and bending ratios (r/D = 1 to 2.5) were evaluated in different flow conditions. The wear location shifted to the upper section of the bend and its magnitude was significantly reduced with an increase in pipe diameter and bending angle. The dynamics of multiphase slurry through different bends was analyzed to understand the complex wear phenomenon. The simulation result showed good agreement with the previous published findings. Finally, the least erosion-affected pipe bend design was suggested for the slurry transport unit.