Mesh cathode- an economic electrode for various applications

Stainless steel twin wire cathode mesh is produced from SS316L grade materials to wind cathode frames in sludging electrowinning cells. Twin wire wound mesh is produced from 0.152mm diameter wire and provides great surface area for precious metal electrowinning. Electrowinning mesh is also known as knitted stainless steel mesh which is a porous blanket of layered and knitted stainless steel wire which is used in electrowinning cells. This mesh can be fabricated to fit all cathodes and can be easily re-used by washing the metal on the cathode. This mesh can be used in new or old electrowinning cells and as per experts, the knitted stainless steel mesh can last for maximum 20 months before replacement.

There are numerous advantages of stainless steel mesh cathode such as

·        Reduced flux costs

·        Excellent labour savings as it is easy to install and needs installation only once in a lifetime

·        No melting or drying

·        It ensures excellent solution flow over big surface areas

·        It offers improved precious metal recovery, reduced slag loss and smaller melting furnace

·        It is dimensionally stable as it doesn’t sag after few hours of usage

·        Eliminates wire in bottom of cell

·        Low carbon content steel wool costs eliminated

·        Extends furnace liner life

·        No steel wool type ends and no environmental dangers

·        Knitted stainless steel wool stays for approximately 20 months

Mesh cathode is one of the types of flow-through cathode which is a three-dimensional cathode because of the fibrous or particulate nature of the cathode. Flow-through cathode has high real-to-apparent surface area ratio which can reach 10,000. The mesh cathode has an intertwining matrix of conducting fibers through which the contaminated solution flows and on which the metal deposits. Mesh cathode can be used as the anode in the conventional plating cell and metal can be stripped from flat cathode to recover the heavy metal. Mesh cathode cells have low capital costs and low removal limits as the plating mechanism is simple. During the copper and cyanide electrochemical removal from a heavy-metal-laden wastewater using a mesh electrode, the removal of 98% and 99% could be reached for cyanide and copper, respectively after 30h, however, the operation of mesh cathodes was affected such as blockage in the mesh by unequal depositing of metals in the mesh or due to huge particles being caught in the matrix, high operating costs as the process is complicated and batch processing of the solution.

 As per a study of the effect of cathode-mesh electric field on a streak image tube, pulse current density followed by a critical field value exists. Electric field is increased when the field strength is lower than the critical value in order to improve the temporal resolution of the image tube but the temporal resolution can’t be improved if the field is greater. The critical electric field is 10kV/mm under current density conditions of 20A/cm2 which is important for designing the streak image tube.