CPU - Condensate Polishing Unit

In water treatment, a CPU (Condensate Polishing Unit) is a specialized system used to treat and purify the condensate water generated in power plants and industrial steam systems. The condensate is the water that forms as steam condenses after being used in various processes.

The primary purpose of a CPU is to remove impurities and contaminants from the condensate water before it is returned to the boiler or reused in the system. This helps prevent corrosion, scale formation, and other potential issues that can occur when untreated or poorly treated condensate is reintroduced into the system.

System Components

Cation Exchange Vessels: The CPU includes cation exchange vessels containing a bed of cation exchange resin. The cation exchange resin helps remove positively charged ions, such as sodium, calcium, and magnesium ions, from the condensate water.
Anion Exchange Vessels : The CPU also includes anion exchange vessels containing a bed of anion exchange resin. The anion exchange resin helps remove negatively charged ions, such as chloride, sulfate, and nitrate ions, from the condensate water.
Mixed Bed Polisher : After passing through the cation and anion exchange vessels, the condensate water may go through a mixed bed polisher. The mixed bed polisher contains a mixture of cation and anion exchange resins to further enhance the water purity by removing any remaining traces of ions.
Filtration System : Some CPU systems may incorporate a filtration system, such as activated carbon or multimedia filters, to remove particulate matter and further improve water quality.
Monitoring and Control : A CPU typically includes instrumentation and control systems to monitor the water quality, flow rates, and resin performance. This helps ensure the effectiveness of the treatment process and allows for timely regeneration or replacement of the ion exchange resins when needed.

Significance & Advantages

The treated condensate water from the CPU is then typically returned to the boiler or reused in the steam system, contributing to efficient and reliable operation while minimizing potential damage or issues caused by impurities.
Regular maintenance, including resin regeneration, monitoring of water quality parameters, and occasional resin replacement, is necessary to ensure the continued performance and efficiency of a Condensate Polishing Unit.