PERFORMANCE CHARACTERISTIC OF CENTRIFUGAL SLURRY PUMP HANDLING SOLID LIQUID MIXTURES

Abstract

Centrifugal slurry pumps are generally used for hydraulic transportation of solids for disposal of ash produced in thermal power plants and mineral tailings in material processing plants. Centrifugal slurry pumps are the development of conventional centrifugal pumps and are characterized by robust design, use of wear resistant materials, large passageways for the free passage of solids and ease of maintenance. They are normally single stage, end suction type having radial and mixed flow configuration to facilitate the motion of solid particles. The performance of the centrifugal slurry pump plays a key role in the successful operation of the hydraulic transportation system. The objective of present research work is to numerically predict the performance characteristics of centrifugal slurry pump handling bottom ash slurries of 20, 30 and 40 % concentration (by weight) using a commercial software Fluent. For numerical model, multiple reference frame (MRF) model along with multiphase mixing model is used to simulate slurry flow through the pump. It has been observed that, the pump performance with the slurry was lower than that with clear water and decreases with increase in the solid concentration. The numerical values of head, power and efficiency over the operating range of the pump have been found reasonably agreement with kazim et al. [ 19] head reduction correlation results at various rotational speeds and solid concentrations. Affinity law relationships for head, power and capacity have been applicable for the slurry pump handling clear water.