Abstract

The invention concerns a method for the preparation of finely divided calcium hydroxide, where burnt lime or calcium oxide is comminuted in an impact disintegrator (10), into which in addition to the calcium oxide part of the required amount of water led to wet the particles obtained, to bind the dust and to initiate the reaction, and the material comminuted and wetted in the impact disintegrator is led into a screw conveyor (20) being in connection with the impact disintegrator. The invention is characterized in that - the reaction is essentially completed in the screw conveyor (20) by feeding into the same the remainder of the amount of water needed for the reaction, and that - the temperature of the material in the last part of the screw conveyor is kept at a target temperature, which is essentially the vaporization temperature for water at the prevailing pressure, and the material is kept at the target temperature for a certain period of time, about 5...15 s, preferably about 10 s.

IPC Classes  ?

• C04B 2/02 - Lime
• C04B 2/08 - Devices therefor
• C01F 11/02 - Oxides or hydroxides
• C01F 11/16 - Purification
• B02C 13/22 - Disintegrating by mills having rotary beater elements with intermeshing pins
• B02C 13/286 - Feeding or discharge
• B02C 23/18 - Adding fluid, other than for crushing or disintegrating by fluid energy

Abstract

a) at the shaft (22) of the second rotor (18) in the opposite direction.

IPC Classes  ?

• B02C 13/20 - Disintegrating by mills having rotary beater elements with two or more co-operating rotors
• B02C 13/09 - Disintegrating by mills having rotary beater elements with horizontal rotor shaft with beaters rigidly connected to the rotor and throwing the material against an anvil or impact plate

Abstract

The invention concerns a method for maintaining of an overpressure in an impact mill during treatment of material to be carried out therein, and an impact mill that can be pressurized. The method is characterized in that the material components needed are fed into the rotor space by a feeding arrangement enduring pressure differences; the material exiting from the rotor space is discharged by a discharge arrangement enduring pressure differences, and the target pressure in the rotor space is secured by a pressurized gasket fluid, the pressure of which is kept at least the same as the target pressure of the rotor space, or preferably slightly higher than the target pressure of the rotor space. The gasket fluid is led beneath a gasket located between the rotor shafts, and/or beneath a gasket located between the rotor shaft and a support adjacent thereto.

IPC Classes  ?

• B02C 13/286 - Feeding or discharge
• B02C 13/22 - Disintegrating by mills having rotary beater elements with intermeshing pins

Abstract

Method for the preparation of finely divided calcium hydroxide, where calcium oxide is comminuted in an impact disintegrator into which in addition to the calcium hydroxide a small amount of water is led to wet the particles obtained and to bind the dust. The calcium oxide powder is led to a conveyor being in connection with the impact disintegrator and operating as a pre-quencher, to which conveyer water is added and where the material is subjected to a kneading effect. The material which is a mixture of calcium oxide and calcium hydroxide is led from the conveyor to a cistern operating as post-quencher, to which cistern the remaining portion of the total water amount required for quenching is added. The amount of water added to the impact disintegrator and to the pre-quencher is altogether 20...50 % of the total amount of water required for quenching, preferably about 1/3 of the total amount of water required for quenching, and the amount of water added to the post-quencher is 80...50 % of the total amount of water required for quenching, preferably about 2/3 of the total amount of water required for quenching.

IPC Classes  ?

• C01F 11/02 - Oxides or hydroxides
• C01F 11/16 - Purification
• C04B 2/04 - Slaking
• C04B 2/08 - Devices therefor

Abstract

The invention concerns an impact mill having a rotor apparatus comprising two concentric rotors (30, 40) equipped with coaxial shafts (10, 20), said rotors comprising blade rings (31, 32,.... and 41, 42, respectively), said blade rings being located within each other, and wherein said shafts (10, 20) are arranged within each other on the same side of the rotors (30, 40). The invention is characterized in that into the inner shaft (10) or into the outer shaft (20) is made at least one channel (14, 51, 52 or 25), running in the shaft, for the oil needed for lubrication of the bearings (11, 12) of the inner shaft.

IPC Classes  ?

• B02C 13/20 - Disintegrating by mills having rotary beater elements with two or more co-operating rotors
• F16C 33/10 - Construction relative to lubrication
• F16N 7/00 - Arrangements for supplying oil or unspecified lubricant from a stationary reservoir or the equivalent in or on the machine or member to be lubricated