Start Up and Commissioning of the Pipeline

Objective of the commissioning

·         To bring the constructed / installed system to deliver the desired function.

·         The Pipeline commissioning means introducing crude/ product/Gas in the pipeline from originating station, filling the entire length and then start delivering to receipt system.

What we need prior to commissioning?

·         The pipeline and associated facilities are completed in all respect

·         All Fire and Safety equipments / facilities are tested and commissioned

·         Availability of dedicated communication

·         Statutory Clearances obtained

·         Availability of Product (HSD)/ Crude oil – Not less than line-fill

·         Required Manpower is placed at all locations

·         Availability of water and its disposal plan

·         Availability of a dedicated commissioning team

Commissioning Steps : 

1.      Drying – Purging of super dry air

Compressed Super dry air is purged using air compressors with accessories viz. Moisture Separator, Oil Separator and Dryer. The air shall be supplied in the pipeline at (-) 20 deg. C dew point.

Super dry air with dew point (-) 20 deg. C will have sufficient capacity to absorb water vapour to the extent of 30 % of the desired capacity.

2.      Vacuum Drying

The process utilizes high capacity vacuum to reduce pressure within the Pipeline to a level from 760 Torr to 40 Torr. At this pressure (40 Torr), any water within the pipeline will start boiling and vaporizing.

Air left inside the Pipeline is subjected to a vacuum of 40 Torr, the water vapor will expand approx. 18.8 times, which will be displaced using high capacity vacuum booster pumps (rated capacity 5000 CuM/Hr)

When the vacuum of 7.6-10 Torr is achieved, it is confirmed that whole pipeline system has been dried to required level.

3.      Nitrogen Purging

At vacuum level 7.6 Torr and dew point (-) 20 deg.C, the oxygen content inside the Pipeline is 0.20%. To further dilute the oxygen content, nitrogen purging isdone almost 13 times more than pipeline volume. This will reduce oxygen content to 0.015%, which is considered negligible.

Now the Pipeline system is ready to receive Gas.

Daftar Pustaka :

http://petrofed.winwinhosting.net/upload/15-18June11/13.pdf