To provide a crystallization method and a crystallization apparatus capable of producing mono-dispersed particles within a narrow particle size distribution width in cooling crystallization without seed crystals.
The crystallization method is for precipitating a crystal of a compound from a saturated solution, in which the compound is dissolved, by cooling the solution in cooling crystallization without seed crystals and the method is characterized in that the number of particles of the crystal precipitated from the saturated solution and the concentration of the saturated solution are actually measured while the solution being cooled according to the cooling temperature profile; the absolute number of particles of the crystal precipitated from the saturated solution is calculated by a mass balance from the actually measured number of particles and actually measured concentration; the excess crystal is dissolved in the solution by heating the saturated solution and carrying out heat control to control the absolute number of particles to be an aimed value when the absolute number of particles exceeds a threshold value; and thereafter, the saturated solution is cooled again according to the set cooling temperature profile.
| JPS62247802A | 1987-10-28 | |||
| JPH01176214A | 1989-07-12 | |||
| JPH05111602A | 1993-05-07 | |||
| JPH11267402A | 1999-10-05 | |||
| JP2005087087A | 2005-04-07 | |||
| JP2008273933A | 2008-11-13 |
Tadashi Takahashi
Takashi Watanabe
Suzuki Mitsuyoshi
Kazuya Nishi
Yasuhiko Murayama
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