Increasing SWRO efficiencies through turbocharger optimization: Fid-Bau Portal

Increasing SWRO efficiencies through turbocharger optimization

Ma, Ying / Kadaj, Eric R.

Turbocharger efficiency plays an extremely important role in desalination with membrane process technology because it directly impacts the cost of producing desalinated water. The goal of every energy recovery manufacturer has been to improve the performance of their products, especially the efficiency. Pump Engineering has used its close loop design methodology to explore the turbomachinery design specifically in desalination and has succeeded in achieving a 10 % efficiency increase on average in the last decade. One successful example was introduced in this paper. The close loop design methodology combined with the existing database suggested that a higher rotating speed can increase the efficiency. Therefore, a new turbocharger was designed, simulated and machined. The comparison showed that there are no significant geometry differences between the new and old turbocharger, except the dimensions of rotors have been decreased. Both the simulation and test results showed that the new turbocharger has better performance. The test results proved that the new turbocharger design has 5.2 % higher efficiency compared to the old design. The absolute and relative energy saving of the new turbocharger design was also calculated and explained here. With the new design, the turbocharger could save an additional US dollar 2650 per year, or an extra 7.8 %, for a small flow capacity of 772 m³/d. Furthermore, it appears that the increase in the turbocharger efficiency has no drawbacks on other equipment nor on the turbochargers themselves.