Numerical investigation of Bi-model slurry transportation through horizontal pipe bend

Slurry transportation through a pipeline is an essential element in modern processing and mining industries across the globe. However, this mode of transportation is a complex phenomenon that requires high suspension stability of the particulates and high-energy requirements to deliver the solid materials continuously. Various studies and techniques are available concerning solid transportation through a long-distance pipeline. However, all the methods focus on basic slurry parameters like pressure drop (PD), concentration and velocity distribution for the uni-model slurry system. Further, in a real-life situation, multiple particles of different sizes and char-acteristics transport with the carrier fluid (generally water). Thus, an accurate bi-model slurry system must be developed to validate the long-distance transportation characteristics. Therefore, in the present work, a computational study is carried out through a horizontal bend with two different particles, Silica Sand (SS) and Fly Ash (FA), at four mixture ratios' (65:35, 75:25, 85:15 and 95:05) to investigate the slurry flow characteristics through 90 degrees horizontal pipe bend. Eulerian multiphase model coupled with RNG k-epsilon turbulence model is used for a wide range of velocities Vm = 3-5 m/s at efflux concentrations Cw = 40-60%. The computational results are also synchronized with experimental data for bi-model slurry flowing through a horizontal bend with a bend radius of 148.4 mm and a diameter of 53 mm. The work outcomes reveal a significant drop in pressure with an increase in the percentage of FA in a slurry mixture. It is found that a slurry mixture (SS: FA) ratio of 65:35 is said to be the most efficient mixture combination in terms of energy efficiency for long-term transportation. Further, the contours of the solid concentration, granular pressure (GP), granular temperature (GT) and wall shear stress (WSS) are also envisaged and discussed in detail to analyze the effects of FA in SS slurry.

Automated summary

Slurry transportation through a pipeline is complex and requires high suspension stability and energy to deliver solid materials. Most studies only focus on basic parameters for uni-model slurry systems, ignoring the effects of multiple particles. This study investigates the characteristics of bi-model slurry flow through a horizontal bend, revealing that a slurry mixture ratio of 65:35 is the most efficient for long-term transportation due to a significant pressure drop.