ELTECH LIDA® ANODES - A Brief Review
LIDA® anodes utilize an innovative and patented design: a titanium base with a mixed metal oxide conductive coating. This coating forms a solid solution with the titanium substrate and is an excellent electronic conductor.
The mixed oxides are formed
on the surface through a process of thermal decomposition, creating an oxide
film which is typically anhydrous and almost insoluble in acids. Thermal control
of this process causes the mixed oxides to recrystallize, further increasing
their chemical stability.
These anodes are often referred to as composite anodes. Physically, this term
refers to a ductile, corrosion resistant base metal covered with the highly
conductive stable film described above. The base metal, titanium, provides the
required toughness for the system. The titanium substrate is classified as a
"valve metal" or film forming metal. Such metals in their natural
state are protected by thin, self-healing, tightly adherent oxide films which
are acid resistant and resist the passage of current in the anodic direction.
Thus, if an attempt is made to operate a valve metal as an anode, it is necessary
to raise the potential of the valve metal surface to a high value in order to
pass significant current through the anode.
Then, in order to use titanium as a realistic impressed current anode, the growth
of the insulating oxide must be prevented. The electroconductive film applied
to the surface of titanium satisfies this requirement and permits the flow of
electrical current at a low and steady voltage.
The wear rate of the LIDA® anodes is extremely low and uniform. The thickness
of the mixed oxide film decreases linearly with time at all points on the surface.
The wear rate of the anode is between 3 and 6 milligrams/ampere-year, and is
constant over all current densities in general or frequent use.
Elgard LIDA® anodes are resistant to abrasion with a hardness of approximately
6 on the Mohs scale. ELTECH mixed metal oxide anodes are available for soil,
fresh water, mud and seawater environmently. These anode systems function reliably
in cathodic protection systems in the soil as deep well or shallow groundbeds
as well as in natural water applications.
LIDA® anodes for soil application are available in two lengths, and two diameters,
to meet a range of current output requirements: 50 and 100 cm (20 and 40 inch)
and two diameters, 1.6 and 2.5 cm (.64 and 1.0 inch.
They are available as a single-unit assembly, or as a multi-unit assembly on
a single cable. ELTECH wire or tubular anodes are also available as cannestered
anodes, surrounded by carbonaeous backfill to minimize installation time and
handling on site. ELTECH mixed metal oxide anodes are also available in wire,
rod, mexh, ribbon, and disc form for a variety of impressed current CP applications.
According to OSHA Regulations, the precious metal coating and the substrate to which it is applied constitute and "Article." An "Article" is defined as being a manufactured item which is formed with specific shape or design during manufacture which has end-use function dependent in whole or in part upon its shape or design during end-use and which does not release or otherwise result in exposure to a hazardous chemical under normal conditions of use.
An "Article" is specifically excluded from the scope of the Hazard Communication Rule. As such, no MSDS would be required for sale of coated substrates.