Energy consumption and operational aspects of on load ball cleaning systems

Abstract

On load sponge ball cleaning systems have been proved to remove brine side fouling, maintain high heat transfer rates and high performance of MSF evaporators. Besides capital costs, service, and costs for sponge balls, the energy consumption of the system has to be taken into account. Energy consumption is influenced by hydraulic and exergetic losses of the system. Especially the exergetic losses of the system by recirculating the balls with hot or cold water influence the energy consumption considerably. With unfavourable conditions the continuous hot water recirculation from the brine heater outlet to the coldest recovery stage increases the heat consumption by as much as 5% with a 22,000 m 3/d MSF. Specially designed ball recirculation systems bring this heat loss down to negligible values. Besides the energy consumption the operational aspects of the different ball recirculation systems have been evaluated.