| 摘要 |
<p>There is provided a process for desupersaturation of supersaturated calcium sulfate solution which comprises injecting solutions into an inverted truncated substantially conical reaction vessel proximate to the apex thereof. Said vessel is provided with crystalline calcium sulfate, an entry port proximate to the said apex, an exit port proximate to the base and, in a preferred embodiment, a second exit port for the removal of excess calcium sulfate suspension. The size of the vessel, the amount of calcium sulfate charged and the rate and volume of injected supersaturate are predetermined to provide intimate contact between the supersaturate and the calcium sulfate charged while providing a volume adequate to permit sufficient settlement of the upper portions of the thus formed calcium sulfate suspension o that the treated waters may be drawn off at the top of said vessel through the first exit port in a form substantially free of suspended calcium sulfate. The charged calcium sulfate provides seed cores for the crystallization of the dissolved calcium sulfate whereby the charged waters are desupersaturated. A novel improvement in the otherwise conventional apparatus utilized, lies in the provision of a second exit port in the circumference of the vessel for the removal of calcium sulfate suspension to control the amounts thereof. Such a second exit port is suitably located in the lower portion of the vessel but above its apex.</p> |
