Method and apparatus for in-line production of milk of lime into an in-line production process of PCC arranged in connection with a fibrous web machine

摘要

A method and apparatus for in-line production of milk of lime into an in-line production process of PCC arranged in connection with a fibrous web machine. In the solution, lime is slaked in a slaking apparatus at a temperature of at least 80 degrees. The produced milk of lime is cleaned by separating excessively large calcium hydroxide particles immediately prior to introducing the milk of lime into the production process of PCC. The milk of lime is introduced into the in-line production process of PCC located in the production line of the end or intermediate product of the fibrous web machine.

主权项

1. A method for production of milk of lime in an in-line production process of precipitated calcium carbonate (PCC) arranged in connection with a fibrous web machine, the method comprising:
comminutating quick lime in a comminuting apparatus which forms a first part of a slaking apparatus; feeding water to the comminuting apparatus to form a slurry of comminuted quick lime and water; feeding the slurry of the comminuted quick lime and the water to a second part of the slaking apparatus; adding water to the second part of the slaking apparatus; slaking the comminuted quick lime in the second part of the slaking apparatus at a temperature of at least 80 degrees Celsius to produce milk of lime; cleaning the milk of lime by separating oversize particles and agglomerates; wherein
the second part of the slaking apparatus includes one of a displacement pump and a dynamic pump with a subsequent pressure pipe, whereby a retention time of the comminuted quick lime in one of the displacement pump and the dynamic pump with the subsequent pressure pipe corresponds a time for the slaking of the comminuted quick lime,feeding the milk of lime produced from one of the displacement pump and the dynamic pump with the subsequent pressure pipe to a cleaning step,in the cleaning step, removing oversize calcium hydroxide particles immediately prior to introducing the milk of lime to the in-line production process of PCC, andwherein the milk of lime is introduced into the in-line production process of PCC at a production line of the end or an intermediate product of a fibrous web machine.