Situated approximately 160 km North of Jeddah, the RAWEC owned Rabigh Independent Water Steam Power Producer (IWSPP) is located within the Rabigh Complex, the integrated refinery and petrochemical facility jointly owned by the 50/50 joint venture of Saudi Aramco and Sumitomo Chemical of Japan, and the largest Foreign Direct Investment in Saudi Arabia. (22.705621, 39.017356)
The Plant consists of a highly reliable combination of equipment, which efficiently and cost effectively produces environmentally acceptable electricity, water and steam. The Plant has been designed to operate fully loaded at the contracted capacity throughout the year except during scheduled outages which are aligned with the 4 yearly T&I of the Petro Rabigh complex. The plant design is driven by the following objectives:
- maximize the reliability of the plant
- ensure ease of operation
- minimize maintenance requirements
- maximize plant efficiency
- minimize auxiliary power requirements
- produce all utilities in economically sustainable manner
- minimize life cycle cost and
- ensure compliance with the environmental and safety regulations
Rabigh IWSPP, as a utilities provider, consists of a conventional thermal power plant and desalination facility with a total installed capacity of 840 MW Power, 6,110 t/h Steam and 12,000 t/h Water.
Rabigh IWSPP Major Equipment:
- 13 Boiler Units
- 7 Steam Turbine Units
- 24 RO Trains
- 13 Electrostatic Precipitator Units
- 5 Flue Gas Desulphurization Units
Power and Steam Production
The conventional thermal power plant is supplying power and steam to the whole Rabigh complex. The co-generation power plant consists of 13 steam generators (boilers) with 470 t/h capacity each and 7 steam turbine generators with a maximum output of 120 MW each, which efficiently and cost effectively produce reliable steam and electrical energy and throughout the year. The boilers are fired on heavy fuel oil that is received from the Petro Rabigh complex. To ensure environmentally acceptable operation, the flue gases are cleaned by means of electrostatic precipitators and a flue gas desulfurization process.
The Rabigh IWSPP 1 & 2, running as an integrated plant, is synchronized with the Grid through a new SEC Substation adjacent to the Rabigh Complex. Since the construction completion of Phase 2, this connection further enhances the backup power supply capacity of the integrated plant. Further, upon detection of grid conditions that require the Rabigh Complex from disconnecting from the grid, the Rabigh IWSPP has the capability to automatically switch to island mode operation, assuring continuation of uninterrupted utilities supply to Petro Rabigh.
The plant supplies steam on various pressure levels. The steam turbines are consuming High-High Pressure (HHP) steam. Moreover, through the Turbine Extraction System, steam of different conditions is extracted from the turbines at different stages. Through extraction, the plant can supply steam at various pressure level of High Pressure (HP Steam), Medium Pressure (MP Steam) and Low Pressure (LP Steam) to Petro Rabigh. Various steam conditioning is also achieved through let down stations and appropriate de-superheating.
The power plant also produces demineralized water through a water demineralization process which consumes water that is produced by the desalination plant.
Desalinated Water Production
With a capacity of 12,000 t/h, the Seawater Reverse Osmosis (‘SWRO’) Desalination Plant within RAWEC’s facilities is a three pass RO plant consisting of 24 individual RO units. Using a combination of seawater and brackish water membranes, it supplies high quality desalinated water at lower cost than similarly-sized multi-stage flash (“MSF”) thermal desalination plants.
The interconnection of desalination plant phase 1 & 2 allows shifting of desalinated water between two plants. Furthermore, the holding time of desalinated water tanks has increased during the addition of Phase 2, increasing the reliability of desalinated water supply.
The desalination plant employs energy recovery turbines to partially recuperate the power consumption of the high pressure pumps. This assists in achieving low auxiliary power consumption and increases the overall efficiency of the plant.