| Abstract: | Because of the ever increasing energy demand and costs, different recovery systems are becoming more and more useful and economical.On the Reverse Osmosis (RO) Systems about 70% of the energy for pumping is wasted at pressures of 800–1000 psi. This paper will discuss the application of reverse running centrifugal pumps as power recovery turbines to recover up to 80% of that energy. The economics of Hydraulic Power Recovery Turbine (HPRT) systems are explored with respect to the equipment cost, operating costs and payouts for the different sizes of R.O. Systems.HPRT's come in various sizes and types and configurations with efficiencies being a function of specific design, flow rate, pressure and speed. Typical design features of HPRT's are described for use in the R.O. System.Different schemes and equipment arrangements are available and require the use of steam turbines, motors, electric generators, clutches, and speed controls or a combination of the above for optimum results. Recommendation of the most economical equipment arrangement for the R.O. System is discussed.Head vs. capacity and BHP vs. capacity relationships are an essential criteria for selection and operation of HPRT's. An overview of the performance characteristics is illustrated. The conclusions will point to the use of reverse running pumps as hydraulic turbines for economical, reliable and efficient recovery of energy from the waste brine circuits of reverse osmosis system. |
