Local cathodic protection power stations

Figure 12-2 shows as an example the arrangement of the anode installation for the local cathodic protection of pipelines in a power station. The cooling water pipelines have a nominal diameter of DN 2000 and 2500 and a covering of earth up to 6 m. The fire-fighting pipelines have a nominal diameter of DN 100 and a covering of 1 m. All the pipelines have a bitumen coating. 

Fig. 12-2 Local cathodic protection in a power station. deep anodes O horizontal anodes Potential readings Ccu-cuso4 volts (A) free corrosion potential before commissioning the cathodic protection (B) 4 months after switching on...

Pumping or compressor stations are necessary for the transport of material in pipelines. These stations are usually electrically separated from the cathodically protected long-distance pipeline. The concrete foundations are much smaller than in power stations and refineries. Since the station piping is endangered by cell formation with the steel-reinforced concrete foundations, local cathodic protection is recommended. 

The effective costs of a cathodic protection station depend very much on the local conditions, particularly on the costs of the power supply and the extent of the anode bed. Table 22-2 contains the costs of a protection station with four silicon iron anodes. 

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