Exam Question

### (a) Explanation of Reasons for Purifier Overflow
A purifier overflow signifies a critical operational issue where the lighter phase (purified oil) escapes through the heavy phase (water/sludge) outlet. This indicates a failure in maintaining the correct oil-water interface or a malfunction in the discharge system. The primary reasons for this phenomenon are:
* **Incorrect Gravity Disc (Interface Ring) Size:**
* The gravity disc, or interface ring, establishes the precise position of the oil-water interface within the separator bowl. Its internal diameter is crucial and selected based on the specific gravity difference between the oil and water at the operating temperature, as well as the desired interface position.