Space-saving PHEs chosen for turbine cooling

The turbine systems have been supplied by Rockfin Sp. z o.o., a long-term customer of Alfa Laval Poland which, in turn, supplied the PHEs for cooling applications. With space at a premium, the flexibility and compactness of the PHEs, combined with Alfa Laval’s capability to supply an innovative, non-standard installation design were major advantages for Rockfin.

Request for distillate coolers

The original request to Alfa Laval from Rockfin was for wanted to simplify the system as much as possible and was not prepared to accept any reduction in cold water flow or a controlled bypass system on the heat exchanger’s cold water side. The entire cold water flow must pass through the heat exchanger. Also, since space at the front of the  the bypass pipe from the pressure plate. If it becomes necessary some time in the future to change the flow proportions between the PHE and the bypass, it can be achieved easily by changing the size of the orifice. distillate coolers. The challenge with using PHEs for this application was that the cooling water flow was almost four times greater than the hot distillate flow. It was also a much bigger flow than was required by the PHE to achieve the desired cooling result.

Rockfin wanted to simplify the system as much as possible and was not prepared to accept any reduction in cold water flow or a controlled bypass system on the heat exchanger’s cold water side. The entire cold water flow must pass through the heat exchanger. Also, since space at the front of the PHE was limited, no valves could be situated there.

An innovative solution

Working with Rockfin, a sales engineer from Alfa Laval Poland suggested a typical PHE with a non-standard installation design. A bypass pipe was mounted between extra cooling water connections on the pressure plate at the back of the unit. As continuous water flow through the exchangers was expected during operation, a regulation valve on the bypass pipe was not required. It was simply a case of installing an orifice there to ensure the correct flow proportions between the PHE and the bypass.

Service of the PHE unit with a bypass mounted on the pressure plate is as easy as servicing a standard PHE. The plates can be cleaned without detaching the bypass pipe from the pressure plate. If it becomes necessary some time in the future to change the flow proportions between the PHE and the bypass, it can be achieved easily by changing the size of the orifice.

Alfa Laval PHEs chosen for all three applications

Based on the success of Alfa Laval’s distillate cooler solution, Rockfin also chose PHEs for the air seal oil coolers and the hydrogen seal oil coolers, a total of 10 sets. A spokesman for Rockfin said:

“We see Alfa Laval as a reliable supplier with a wide portfolio, fast response, and deep technical knowledge and experience.” 

The Medupi Power Station is still under construction. The first 800 MW turbine is expected to be commissioned in 2012.