2023 Zia Oil Contamination in Urea Manufacturing Process – A Case Study on its Impact
The problem of oil ingress to urea process streams is prevalent in most of the urea plants. An elevated oil content can impact the plant operation in several ways. Most recent issue faced at FFC-GM is the contamination of Urea Process Condensate and ultimately causing the chocking of degasifier packing after passing through the Cation.
Actions taken to manage the problem:
1. More than 70% black (problematic) packing removed from degasifier.
2. Frequency of steam regeneration of carbon filter increased.
3. Checking of degasifier maximum flow on fortnightly basis.
4. Partial draining of degasifier on fortnightly basis.
5. Immediate diversion of urea process condensate in case of any upset at urea plant with improved coordination.
6. Analysis of organic matter by lab once in a day.
7. Removal / observation of oil from cation top vent once in a day.
8. Carbonate vessel (V-103) operating level value increased from 14 to 20% to minimize the impact of process upset at urea.
9. Flushing /overflow of CD header tank (T-105) carried out.
As the only solution is to control the oil ingress in system at the source. Following actions will resolve the issue on long term:
1. To track record of oil consumption of all the machines and proper maintenance to minimize the seal leakage issues.
2. To carry out study for decanting accumulated oil in carbonate vessel V-103 top surface after proper engineering study.
3. In many plants “oil sealing system” has been replaced with “water sealing system” at plungers of NH3 feed pump in order to counter the problem. Same to be studied for our system.
4. Re-Evaluation of frequency and oil analysis in process streams of ammonia / urea plants.