RE-REFINING PROCESS AND SYSTEM FOR USE WITH UNQUALIFIED LIQUID AMMONIA IN OIL REFINING WASTE WATER PRODUCTION

摘要

Provided are a re-refining process and system for use with unqualified liquid ammonia in oil refining waste water production. The system comprises: a liquid ammonia rectification tower (1), a first level adsorption tank (2), a second level adsorption tank (3), an extraction tower (8) and an ammonia recovery tower (11), wherein connection relationships and a gas-liquid direction are as follows: a middle part of the liquid ammonia rectification column (1) which separates liquid ammonia from impurities is provided with a feed port, a material circulating port at a tower base of the liquid ammonia rectification tower (1) is connected to a feed port of a first level reboiler (7) at the tower base, a discharge port of the first level reboiler (7) is connected to a feed port of a second level reboiler (6), a material discharge port of the second level reboiler (6) is connected to a circulating feed port of the liquid ammonia rectification tower (1), and a heavy material discharge port at the tower base of the liquid ammonia rectification tower (1) is connected to a feed port of the extraction tower (8). The system may accurately adjust an operation process according to the impurity content of liquid ammonia to be processed such that the treatment process for unqualified liquid ammonia becomes more flexible and efficient. Further comprised is a re-refining process, which uses distillation technology to remove oil, adsorption technology to remove H ₂ S and like gas phase impurities, an extraction method to remove residue such as phenols and the like, thereby making the purification and reuse of unqualified liquid ammonia a reality.