Pulp and paper pumps

Abstract

This chapter provides an overview of the pumps that are used in pulp and paper industry. In pulp and paper industry, high temperatures, very high suction pressures, low NPSHR requirements, poor lubricity, air entrainment, corrosive and acidic mixture of sodium or calcium bisulfite and sulfurous acid, and reliability are major considerations. The standard small process pump in pump and paper industry is the end suction, ANSI B73 or ISO 2858 chemical pump with centreline discharge open impeller and today more often than not mechanical seals. The larger pulp and low concentration transfer pumps are end suction, open impeller and adjustable wear plate, packing or mechanical seal type pumps with centerline discharge. Centrifugal stock pumps are used for consistencies up to approximately 5.5%, above this there are pumps with special internal features such as an inlet fluidizer that will allow consistencies up to as high as 18% consistency to be pumped. The pumps in the paper machine area are the screen, refiner, washer, cleaner and head box units as well as the refiner reject pump.