Pressure screening: changes in pulp properties in the screen basket

A pilot-scale pressure screen was used for experiments on changes in pulp p roperties in the screen basket. Pulp properties were found to undergo chang es in both the axial and radial directions with respect to the screen baske t. The axial change takes place because small particles pass through apertu res readily, while large particles tend to remain inside the basket. The ra dial variation in pulp properties occurs because the water, flowing radiall y, compress the fiber network close to the screen plate as water and fines pass through. According to the probability theory of pressure screening, th e properties of the plp also change in an axial direction in the accept cha mber. These changes affect the capacity and efficiency of the pressure scre en.