Case Study - ICL Dead Sea Works

Challenge

Background - Transporting briny water across the Dead Sea

Located in the southern basin of the Dead Sea, ICL Dead Sea Works is a leading global producer and supplier of potash products, extracted using solar evaporation at its 2-meter-deep evaporation ponds and exported to customers in over 60 countries. A drastic drop in the level of the Dead Sea in recent years threatens both the mineral extraction operations and local tourism, which brings in millions of dollars to Israel’s economy and provides thousands of jobs. A unique and complex project by ICL Dead Sea Works to build the largest pumping station in Israel – designed by Royal Haskoning DHV (The Netherlands) - is set to provide the answer.

Technical spec

A 60,000 m3/h flow, up a 43 m incline

The new pumping station will be tasked with pumping salt water from the northern basin to the southern basin. The briny solution will be delivered through 2 km of pipe, before flowing gravitationally through an open channel for 13 km. The facility has two parallel delivery systems from the Dead Sea elevation of -435 m, to the transmission channel at -392 m. Each delivery system itself has four parallel vertical centrifugal pumps (Ebara Corporation), 20,000 m 3 /h each, without non-return valves. Total flow is about 60,000 m 3 /h through a steel pipe Ø3048 mm in diameter. The entire area of
the main delivery system is served by an impressive branched system of Ø350 mm diameter pipes, supplying brackish water for flushing through transmission lines of 14" diameter.

Transporting briny water across the Dead Sea

A specific challenge the client sought to overcome was to protect the main system from hydraulic failure and energy losses. Due to the unique characteristics of the system, such as having no check valves, a siphoned flow section and unstable base ground, it is prone to water hammer, cavitation and air problems. Special protective accessories were needed to prevent severe potential damage.

A further, unique, challenge lay in protecting the protective accessories from clogging with salt sediment, by flushing salt residues out of the system. This would require a regular infusion of treated water into the system during operation to remove salt crystallization residues from every part - especially moving parts. To ensure a constant supply of relatively clean water, some accessories would need to be modified with specially-designed flushing nozzles.

Solution

Complex analysis, system-wide solution

A.R.I. - Dorot is one of just a few companies in Israel, and in the world, able to offer the necessary system-wide solution for a project such as this. As well as complex analysis, A.R.I. - Dorot supplies accessories suitable for any type of liquid, manufactured from structural materials able to withstand harsh industrial conditions, to meet customers’ precise requirements.

Having been commissioned by the project designer and Dead Sea Works to select the model, size and location of suitable accessories, A.R.I. - Dorot used ARIavCAD software to perform both a surge analysis and an air valve analysis.

Experiments were carried out at A.R.I. - Dorot's development laboratory to ascertain the valve specifications required to meet the specific needs of the project. As a result of the various analyses conducted, it was decided that unique, large-diameter vacuum breakers model VB-060 20”, 24" and 16" (Fig.1) would be used to eliminate vacuum damage in transient situations, and D 070 (Fig. 2) dynamic air valves of 4" diameter would be used to evacuate inherent air volume during start-up of the pumping unit. For the flushing system, non-metallic air valves, mainly D-040L 2" (Fig. 3), were selected to ensure sufficient flow through the 5 km supply pipeline.

A.R.I. - Dorot provided the customer and the designer with all the necessary elements - from the equipment, technical materials and three-dimensional drawings, to installation and maintenance instructions and close engineering support - to ensure the success of the project. As a result of the company’s input, the water delivery system is more reliable, and will be able to function properly in the long term.