| 摘要 |
An apparatus and method for treating chemical production plant process condensate such that a contaminant-rich stream and a relatively pure aqueous stream is separately recoverable from the condensate, wherein the contaminants are substantially removed from the condensate by steam stripping and subsequent rectification in a relatively low pressure stripping/rectification tower. The tower overhead is then condensed with a portion of the condensed overhead being returned to the tap of the rectification section of the tower as reflux and the balance being withdrawn as a concentrated stream for reuse in the plant. In a second embodiment, separate stripping and rectification towers operate in series whereby the overhead of the stripping tower is delivered to the lower section of the rectification tower and the rectification bottoms are returned to the top of the stripping tower. The overhead from the rectification tower is then condensed with a portion returned at its top for reflux and the remainder being withdrawn as a highly concentrated stream for recycling to the ammonia plant. The mass flow to the ammonia plant is low enough because of high concentration that ammonia plant modifications are not needed nor is there significant thermal impact. The apparatus may be used in conjunction with existing low pressure equipment, avoiding costly major modifications.
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