feature stories | mining the dead sea Design Flow Design Head 5.18 m3/s 60 m Maximum Pump Hydraulic Power 4430 kW or 4.43 MW Pump Motor Rating 1 5000 kW 5 MW 11 kV 25 m 4m 4.4 m 33.4 m 1.6 m 93 tons 52 tons 64 tons 209 tons Wave Height Wave Period Max Observed Current Velocity 2.25 m 4.6 s 15 cm/s Motor Operating Voltage Pump Vertical Column Height Pump Discharge Section Height Height of Pump Motor Pump Overall Height Pump Column Diameter Pump Weight (Excluding Motor) Motor Weight Weight of Water in Pump Total Pump Weight The wave load marine design conditions are based on bathymetric and hydrodynamic surveys. The Dead Sea is a tideless environment, water level variations are meteorologically-induced. Designing APC’s third intake pumping station: a new design with old challenges and new ones APC is planning to ramp up KCl production to 2.45 million tons per year - current production is 2.0 MTY - and to 3.0 MTY in a projected second phase expansion. DSB intake capacity will be boosted with a higher pumping rate from four simultaneously working pumps. The first step into PS3’s design is a precise study for the derivation of the marine parameters, the crest level of the jetty and the on-shore causeway, the wave loads on the structures and the anticipated sedimentation within the new dredging channel and bassin. Crest level The crest level of the jetty and causeway was estimated based on the water level receding rate, the rise of water level due to meteorological factors, the rainfall runoff to the Dead Sea and the wave run up. The recorded jetty crest level according to the level data with respect to the Aqaba datum is -419 m. The derived crest level is at 3.60 m above the anticipated Dead Sea water level in 2009. Flow, head and power duties For a 2.45-MTY KCl capacity during the first phase of expansion, and 3.0-MTY during the second, PS3’s design must yield a capacity of 250 and 305 Mm3 of brine per year respectively. In terms of pumping station duty, this translates into: • First expansion phase intake: 17.2 m3/s • Second expansion phase intake: 20.7 m3/s Receding level effect The continuous dropping level of the Dead Sea means that the pumping head of the intake station will vary over its 15-year design life time. Each pump will be fitted with 3 different size impellers - a larger impeller will replace the smaller one with pumping head increase. At the start of operation in 2009 the initial pumping head will measure 40 m; in 2024, the end of PS3’s operation, the fitted pumping head will measure 60 m. PS3 is slated to begin pumping in 2009; at that time, Dead Sea level will be around -422.63 m. In 2024 - the end of PS3’s 15 year lifecycle - the Dead Sea is expected to have dropped some 16.5 m to -439.13 m. The safety of pumping operation requires a minimum 5 m as a maintained submergence level to avoid the potentially destructible vortex effect on the impellers; PS3 must then be positioned at a -444.15 m bed level. Dar’s designed alternative adopted by APC for their third intake pumping station provides a number of advantages over the natural alternative. The natural alternative: a sea bed contour line of -445 m • Positioning PS3 at the -445 m required natural sea floor means the intake station would be 600 m away from the shoreline • A very long and expensive access piled jetty • A geotechnically-determined unstable zone Dar-designed alternative: a safe and cost-effective solution • An intermediate PS3 location between the shoreline and the natural sea contour line • A 270-m long jetty - instead of 600 m • An underwater dredged channel between PS3 and the -445 m required contour line will insure 5 m submergence for the impellers up to the last day of pumping To cater for the required pumping flows and heads, PS3 will be equipped with 4 vertical type duty pumps. Each pump will be fitted with three different size impellers - larger impeller will replace the smaller impeller with pumping head increase. 1 PS3’s rough machined impellers for pumps No.3 &4, manufactured at Kubota Corporation, Japan 38