English to Russian Tech/Engineering Engineering (general)

AMMONIA PLANT
OPERATING MANUAL


Purifier cool-down
...

Purifier package cool-down shall start immediately following the completion of all process gas side dry-out activities.
- Using the purifier product gas pressurizing by-pass pressurize the purifier inlet & product gas sides backwards to match the plant front-end pressure
- Maintain the molecular sieve drier regeneration gas source located at the drier process gas outlet
- After equalizing the purifier package process gas side pressure to the plant front-end pressure using XXX fully open the purifier inlet gas YYy, using ZZZ fully open the purifier product gas AAA, and close the associated pressurizing bypass valves
- While monitoring all plant front-end conditions using BBB gradually close the purifier package process gas side bypass CCC
- Prepare the expander and generator for start-up
- Start the expander oil system and using nitrogen from the nitrogen distribution system immediately establish an expander seal gas flow
- After stabilizing both the expander oil and seal gas systems switch the expander seal gas source ***to be process gas taken*** from immediately upstream of the purifier package inlet and manually isolate the nitrogen supply to the seal gas system

Не могу понять часть: "switch the expander seal gas source ***to be process gas taken*** from immediately upstream ..."
переключите линию так, чтобы источником уплотняющего газа детандера был технологический газ, забираемый непосредственно.."

Прошу прощения, если звучит как бред...
Спасибо