Ensure ENGIE a continuous service in the extension of a pipework connection in London

SUEZ has previously carried out several other pre-commissioning Ice Pigging® operations on ENGIE networks, so it was the obvious choice for this project.

The ice slurry was pumped into the pipework to form a long ice pig, this was then driven through the pipework by pushing water in behind the ice.

As the pig traveled through the network it has collected any swarf, welding debris and accumulated sediment which is then discharged from the network suspended in the ice. The operation also collected a large piece of insulation which had been left in the pipework during construction. Any objects like this can cause serious blockages if not removed before the network goes live.

Water in front of the pig is discharged normally while the sediment laden ice had been collected separately in a tanker for safe disposal. All of this took place without exceeding the normal operating pressure of the pipework or causing damage to the pipe wall.

SUEZ was able to utilize existing fittings for all pipe connections and therefore no enabling works were required for the operation.

All pipe was cleaned with Ice Pigging® in one day which related to big time saving at the end of a civils project with a tight schedule. The District Cooling networks in-situ pumps were not used at all during the process which represents a significant energy saving when compared with closed loop flushing, which requires high velocity pumping for several days. 
Ice Pigging produces superior results compared to flushing as it involves a physical cleaning action, rather than just a high velocity flush.