The Multi-Stage Flash (MSF) plants are the majority of desalination plants in the Middle East. MSF plants in the Middle East are currently producing over 70% of the total world capacity of land-based desalting.
The MSF process is used in large-scale distillers to produce potable water from seawater. In essence, the process involves heating seawater to a high temperature then passing it through a series of chambers (or stages) where the pressure and temperature are reduced progressively. This process causes the sea water to boil at each successive stage. The vapor thus released is condensed and collected as distilled water. The process of boiling by pressure reduction is known as "flashing".
In the MSF process, the seawater is invariably heated by low-pressure steam from an associated power plant. A technique known as "brine recirculation" improves the distiller efficiency so that it is possible to produce between 8 and 10 times as much distilled water as the steam consumption of the brine heater.
This quantity is defined as the performance ratio of the unit. The success and popularity of the MSF process is due to its simplicity, inherent robustness and vast amount of acquired experience which resulted in reducing material and operating costs and increasing reliability.
The basic technology of modern large-scale MSF is similar to the early units. However, improvements were implemented during the years such as the development of On-Line Ball Cleaning System, Scale Control Techniques, Corrosion Resistant Materials and increase of unit capacity. Distillers of up to 16.7 migd (million gallons per day) capacity have been built and units of 20 migd are planned. A typical power and desalination plant would have several distillation units with a combined output of up to 120 migd.
This course is designed to provide a comprehensive and up-to-date overview of the MSF distillation technology. The course will focus on practical engineering rather than academic considerations. It is suitable for engineers of all disciplines and water utility employees being trained to purchase, operate and maintain MSF distillers. The course will cover operation, maintenance, Heat Balance, performance, optimization and plant management. It will give clear step-by-step instructions for starting a large MSF plant and for subsequent troubleshooting. Further, the course is suitable for personnel in other types of distillation plant as well as for corrosion engineers and chemists. It deals with those aspects of desalination which significantly affect plant life and costs and includes theory as well as detailed information specific to the MSF process. In general, the course is useful for engineers and operators in both desalination and power plants, and will interest technical personnel in the process industries.
The course will describe also the common interface of MSF desalination with associated power plants in various configurations. Desalination Power Generation matching criteria including hybrid system configuration will be illustrated. The theoretical aspects of the course will be complemented by classroom exercises which will cover typical heat and mass balances, heat transfer calculations, typical calculation of MSF stage heat transfer areas, process streams overall power and desalination plant mass balance. A short session on material selection in MSF desalination and balance of plant including structural aspects is included.