Process water characteristics in the water cooling systems in cooling systems in closed circuit (ISO 3046/1, UNI 8884)

The limits of the process water characteristics must be:

• pH > 7 (absence of acidity)
• hardness ≤ 30 Fr (1 French degree = 10 ppm)
• total alkalinity ≤ 450 ppm
• chlorides ≤ 1000 ppm
• silicon dioxide £ 60 ppm
• iron ≤ 1.5 ppm
• conductivity ≤ 3000 ms/cm
• dissolved gases: H₂S                                          » absent
• ammonia and hydrocarbons                                » traces
• oxygen and other gases                                    » within their solubility limits
• absence of organic substances
• absence of greases and oils