March 12, 2008
During the toubleshooting of ammonia synthesis loop pressure I found that there was some problem across the gas-gas exchanger bcoz its calculated temperature was not matching with the measured temperature. So we checked the Temp gauge at the first place & found it faulty. It was replaced & again temp mismatch was observed but this time difference was lower.
Therefore it was decided to measure the ammonia concentration in the hot gas at the exit for any leakage confirmation. Upon analysis it was found that the exchanger was leaking. It gave an opportunity prior to a major failure & major downtime to rectify the problem in a planned shutdown. On opening it was found that there was minor leakage from the seal packings.
The above probelm also contributed slightly to higher loop pressure due to higher ammonia concentration at the inlet of reactor compared to other plants.
After rectifying this we again found that actual ammonia at reactor inlet was still high. So another simulation was done. This time ammonia liquid separator was the culprit. The VLE data was indicating much lower ammonia concentration than actual one. So after few data points it was decided to check its demister pad for physical condition. On inspection it was found totally damaged & therefore ammonia carryover was taking place.
The rectification lead to a increase of 6% in the capacity at the same loop pressure.
Thus finally this program proved its value to the management and investment they made by sparing me for a month or so to prepare it. I thank again Mr. Pankaj Shah for giving me this opportunity.