-The Wiegand® design convinced because of the favourable operating costs – despite higher investment costs
GEA Wiegand received two large orders for vacuum systems for the expansion of two Indian refineries. In the refinery sector particularly high emphasis is put on low-energy processes because the margins for the processing of crude oil consumer products are very small. In the inquiry the main focus was put on the total cost of ownership. Despite higher investment costs, the Wiegand® design convinced because of the favourable operating costs: a two-stage steam jet vacuum system with liquid ring vacuum pumps as finisher provides a considerable advantage for the final customer, thanks to the saving of motive steam.
The 1st jet pump stage sucks a mixture of hydrocarbon vapours, water steam and inert gases from the vacuum column and compresses the mixture. The gas/steam mixture condenses in surface condensers which again are evacuated by a second jet pump, the motive steam of which condenses in a downstream-arranged surface condenser. The gas/steam mixture is then further compressed in a group of liquid ring vacuum pumps. In this case, three of such vacuum pumps are installed in parallel and another vacuum pump is used as permanent reserve.