Two separate contracts for membrane-based water and wastewater projects in Saudi Arabia have been awarded to ACWA Emirates LLC of Dubai.
The first is a fast-track irrigation water project in Riyadh for provision of 11,000 m³/d by combining groundwater and treated wastewater. The water is required to irrigate a vast expanse of landscaping and tree planting at the Princess Noura bint Abdul Rahman University for Women.
The project includes construction of a reverse-osmosis (RO) desalination plant that will treat the water from two wells up to 1,700 m deep accessing the deep, saline aquifer that lies beneath the city. Cooling towers will initially reduce the groundwater temperature from 70ºC to 35ºC before it passes through a mixed-media filter bed to remove any significant particulate matter.
This will be followed by several stages of RO treatment. An optimal multi-stage process is being used to maximise the efficiency of treated water recovery and minimise reject water.
ACWA’s second contract, for the Ministry of Finance, is for a 12,000 m³/d wastewater treatment and reuse plant at Al Shumaisi in the west of the country between Makkah and Jeddah. This will feature ACWA’s Memtreat® membrane bioreactor technology.
The plant will be constructed with four identical 3,000 m³/day streams, providing the facility with the flexibility during operation to bring in additional treatment capacity as flows increase, and redundancy for maintenance purposes. In this desert area, the main planned use for the high-quality effluent is irrigation.