"Cathodic Protection" can get a little more involved then just adding zincs
Yep, we use a Cathodic Protection system to protect Titanium tubes in the condensers in refrigeration machines using river water as cooloing water. These annodes are connected to a monitoring system. The concept is to protect the equipment while sacrificing cheaper materials that attract the electrolysi,s before it attacks the expensive stuff!
From Wikipedia:
Cathodic protection (CP)
is a technique to control the corrosion of a metal surface by making it work as a cathode of an electrochemical cell. This is achieved by placing in contact with the metal to be protected another more easily corroded metal to act as the anode of the electrochemical cell. Cathodic protection systems are most commonly used to protect steel, water or fuel pipelines and storage tanks, steel pier piles, ships, offshore oil platforms and onshore oil well casings.
Cathodic protection can be, in some cases, an effective method of preventing stress corrosion cracking.
Galvanic CP
Today, galvanic or sacrificial anodes are made in various shapes using alloys of zinc, magnesium and aluminium. The electrochemical potential, current capacity, and consumption rate of these alloys are superior for CP than iron.
Galvanic anodes are designed and selected to have a more "active" voltage (technically a more negative electrochemical potential) than the metal of the structure (typically steel). For effective CP, the potential of the steel surface is polarized (pushed) more negative until the surface has a uniform potential. At that stage, the driving force for the corrosion reaction is halted. The galvanic anode continues to corrode, consuming the anode material until eventually it must be replaced. The polarization is caused by the current flow from the anode to the cathode. The driving force for the CP current flow is the difference in electrochemical potential between the anode and the cathode.
Potential problems
A side effect of improperly performed cathodic protection may be production of hydrogen ions, leading to its absorption in the protected metal and subsequent hydrogen embrittlement of welds and materials with high hardness. Under normal conditions, the ionic hydrogen will combine at the metal surface to create hydrogen gas, which cannot penetrate the metal. Hydrogen ions, however, are small enough to pass through the crystalline steel structure, and can in some cases lead to hydrogen embrittlement.
Hoist!