(3a) Use of IR Camera During Ethylene Unit Startup | AIChE

(3a) Use of IR Camera During Ethylene Unit Startup

Authors 

Dolmage, D. - Presenter, Equistar Chemicals, LP


The Lyondellbasell Morris, IL Plant under went a 70-day turnaround during May & June 2010.  Two FLIR IR cameras (GasFindIR and new GF-320) were used during the commissioning phase of ethylene plant to detect hydrocarbon leaks. 

The ethylene plant systems were first pneumatic tested with either low pressure (70 psig) or medium pressure (245 psig) nitrogen prior to using the IR cameras.  All flanges, connectors, pump seals, and valve bonnets were snoop tested with soapy water.   An IR camera survey step was included in each hydrocarbon startup procedure.  Methane was introduced into the large systems containing nitrogen to produce a gas mixture of 5% CH4 / 95 % N2.  This gas composition was below the LEL yet it was very visible to the IR camera.  The IR camera cannot detect nitrogen (N-N bond), however, it can detect methane (C-H bonds) due to the wavelength selected. 

 The systems were surveyed for leaks as hydrocarbons were introduced in the vapor phase and then again when systems were chilled and liquids were present.  The IR camera was used around the clock to identify leaks missed with the N2 leak test packages.  Leaks do develop as process equipment chill down.  The camera is a powerful tool and made this exercise extremely beneficial.   One hundred and seventy one (171) hydrocarbon leaks were found and were stopped during the plant startup.