Anode protection against acid corrosion

Nowadays, anode protection can protect the air cooler and pipe bank in sulfuric acid plant safely and effectively. In 1966, the air cooler in a German sulphuric acid plant was protected by anode. Since then, more than 10000 square meters of cooling surfaces have been anodically protected in air-cooled or water-cooled sulfuric acid plants around the world. The DC output power of the potentiostat is more than 25 kW, equivalent to 2.5 w of energy per square meter of the protected surface.


In many chemical industry processes, anode protection has been used to prevent corrosion, even for vessels and pipelines with complex geometry. The application of anode protection can protect carbon steel from nitric acid and sulfuric acid corrosion. For sulfuric acid, the application temperature and concentration are limited. At the maximum temperature of 120 ℃, only when the concentration exceeds 90%, can the corrosion protection be effective.


In the production of sulfuric acid with heat recovery and waste sulfuric acid recovery, various concentrations of acid can be encountered at high temperature. Examples of corrosion damage have been observed, such as in sulfuric acid coolers, where corrosion has seriously affected its normal use, and the application of anodic protection can prevent such corrosion damage.


Through the further development of high temperature anode protection technology, economic heat recovery can be realized in some cases, and steam can be produced at high temperature, so as to significantly improve the comprehensive utilization rate of the device. Anodic protection is particularly suitable for stainless steel in acid. In addition to sulfuric acid, other media such as phosphoric acid are also considered. These materials are stable and inactive in nitric acid, but they cannot be passivated in hydrochloric acid. Because of its good passivity, titanium is also suitable for anode protection.


Shandong Linyi Bosi conductive materials Co., Ltd. is a high-tech enterprise specializing in the production of MMO flexible anode, conductive polymer flexible anode and titanium coated anode, mainly providing cathodic protection technology, engineering design, installation and technical services.