Written by: Mike Gardella
The capital city of Amman, Jordan, faced a crisis where 40 percent of its four million inhabitants only had running water from their taps one day a week. To address this critical shortage, the United States and the country of Jordan embarked on an ambitious development plan to convert the brackish water from three large “wadis” (streambeds) near the Dead Sea into fresh drinking water. The plan utilized reverse osmosis as part of a desalinization process to recover up to 85 percent of water put through its planned water treatment plant.
Power Units
Sorensen Systems was privileged to provide six complete hydraulic power operating systems, one each for six pumping stations in series, along the pipeline to lift the treated water from the desalination plant to the National Park Pump Station site in southern Amman. Today, approximately 700,000 people, about one third of the water distributed in the Greater Amman area receive water directly from this system. The project delivers 100,000 cubic meters of water each day to the city, a distance of 25 miles.
The power units designed and built for the project provide the system with a nominal 2,000 psi self-contained, pressurized hydraulic fluid system capable of simultaneously operating the valves at the specified speeds against the specified operating head requirements. In addition, the hydraulic fluid system was designed to automatically, simultaneously and immediately close the valves upon a loss of main electrical power or emergency shut down condition.
Reverse Osmosis
The project is referred to by names of the three “wadis” in the region, Ma’in, Zara Springs, and Mujib. The brackish water available from these streambeds will be subjected to a reverse osmosis (RO) desalination process, which is being increasingly used around the world as an efficient, reliable and cost-effective technology. The RO process uses the osmosis phenomenon, i.e., osmotic pressure difference between the saltwater and the pure water to remove salts from the water. To gain the effect required, there is a need for energy to operate the pumps that raise the pressure applied to feedwater. According to Mike Gardella, a 25 mile transmission pipeline conveys the potable water to Amman through six pumping stations with a total head of about 1,300 m.
An important part of the design requirement was providing the system with dual automatically alternating pumps. The pumps were arranged so that in the event of failure of one pump to generate its rated flow and pressure, the other pump will automatically start. The two pumps don’t run simultaneously. Another design specification called for all necessary controls, transformers, and components to cause the valves to perform the specified functions and operations, requiring only a single 400 volt, 3-Phase, 50 Hz electrical connection.
In addition to the needed potable water, the project had other benefits for the people of Amman. The project will reduce the over pumping of groundwater aquifers, to allow them to recover their full storage capacity as a reserve against future shortages. Also it will release water currently being pumped to Amman from other cities, in order to promote development in the outlying cities.
