The Shortcoming of Titanium Metal in Seawater Desalination

The Shortcoming of Titanium Metal in Seawater Desalination

Although titanium has many advantages. It is also necessary to pay attention to some special cases of corrosion phenomenon in the application of titanium, such as electrochemical corrosion, gap corrosion, and so on. The potential of titanium is negative. The acceleration corrosion of other materials is easy to occur when in contact with other materials, and the cathodic protection method of a sacrificial anode is generally used. At the same time, the connection between the titanium pipe and the pipe plate is prone to gap corrosion in seawater with the temperature of 100 ℃ and the PH value of 8, and the gap can be eliminated by the method of pipe section sealing welding.

In addition, the electric potential of titanium in more than 80 ℃ seawater is lower than other materials. There is the possibility of the hydrogen absorption phenomenon and the production of hydrogen embrittlement. If hydrogen absorption occurs when titanium comes into contact with metals such as iron and zinc, it needs to be protected by the sacrificial anode method. Titanium has the necessary erosion resistance and impact resistance and is not affected by chlorine, nitrogen, and hydrogen sulfide and its compounds. Titanium has a good corrosion resistance capacity of oxidation and acid, is the first choice for the production of such pipes materials. Hydrogen absorption does not occur when titanium is in contact with copper alloys and stainless steel.

Titanium materials are used on the surface of equipment that contacts with high-speed flowing seawater. However, titanium welded pipe for a variety of reasons mainly includes the cost, is not part of the main tube of equipment at present.