CONTROLLER FOR CONVECTION IN HYDROTHERMAL CRYSTALLIZATION COLUMN

摘要

PURPOSE:To improve the speed of crystal growth without lowering the quality of a crystal by distinctly separating a passage of a rising overheated flow of a solution containing a dissolved substance for recrystalization from a passage of a descending cooled flow. CONSTITUTION:A funnel 6 made by forming a stainless steel thin plate is connected to a pipe-shaped body 8 vertically passing through the central axis of a group of seeds 3 and a dome-shaped guide 9 for changing the flow direction is attached over the upper end open part of the pipe 8. Conduit pipes 11, 11... respectively connected to holes 10, 10... made at several positions in the side wall of the funnel 6 are extended downwards from the inside of the funnel 6 and a solution-convection controller composed by assembling the above-mentioned units into one body is set to the inside of an autoclave (pressure cylinder) 1. A solution flow heated at the bottom part of the cylinder 1 and rising along the inner wall of the cylinder 1 is introduced through the funnel 6 and the pipe 8 to the top part of the group of seeds 3. The flow direction is changed to the downward by the guide 9 and the descending flow is allowed to pass through the group of seeds 3. The descending flow is subsequently collected to the conduit pipes 11, 11... and then discharged to the bottom part of the cylinder 1.