FILTER CAKE REMOVAL METHOD OF CLOSED TYPE FILTER AND CLOSED TYPE FILTER

摘要

PURPOSE:To efficiently remove filter cakes attached to a filter plate in a closed type filter by feeding gas in a direction of passage of liquid to be filtered or in a reverse direction at a temperature of 100-150 deg.C and passing it through filter plates. CONSTITUTION:Slurry 16 is fed into a vessel 1 from a liquid feed port 15 and gas for pressurization is fed into the vessel 1 from a pressurization gas feed port 17 to pressurize the interior of the vessel 1 thereby effecting filtration, while filtrate is discharged from a filtrate discharge port 18. Cakes which are separated from the slurry 16 and left in the vessel 1 are washed as required and dried. The cakes are then scraped down by a smoothening arm 4 and discharged to the outside through a discharge pipe 5 and a cake outlet port 7. In each of said filtration, washing processes, the smoothening arm 4, slurry arm 6, etc., perform predetermined actions in response to the signals from a control means. Since gas for pressurization of too high temperature causes thermal decomposition of filter cakes or degradation of filter plate, a temperature 100-150 deg.C is preferable.