Assessing operability of a novel polisher arrangement using MMS

A condensate polisher is intended to remove both particulate matter and ionic material from the condensate. Condensate polishers have normally been placed directly in the condensate system downstream of the condensate pumps. This inline location has certain disadvantages. These disadvantages are discussed. Placing the polisher in a sidestream location, where water is removed from the condensate system, pumped through the polisher, and then returned to the condensate system provides a solution to these disadvantages. Several possible types of sidestream installations is described. This has a polisher taking unpolished condensate from one compartment from one compartment of a divided hotwell in a specially modified condenser and returning polished condensate to the other compartment. The polisher is supplied by its own dedicated pumps, which have a head requirement sufficient only to overcome the pressure drop through the polisher circuit at a flow rate of 110% of maximum condensate flow. This concept is very attractive but has not yet been tested even though it is being installed in several new units. A simulation was, therefore, performed using MMS to provide confidence that this particular sidestream polisher arrangement was operationally viable