The anode baking furnace is probably one of the most demanding applications in so far as the aluminium industry is concerned.
High temperatures and a sulphurous environment place high demands on thermocouples.
TMS is able to offer the following, depending on the type of technology utilised:
Inconell 601 sheathed, wire and bead thermocouples
Although limited life (average 3 months) is obtained, recycling of the outer sheath is possible and replacing the sensor insert would allow full use of the cost intensive protection sheath.
Isopak fluewall thermocouple
Developed in-house, this robust mineral insulated inconell 601 sheathed thermocouple leads to significant improvement in thermocouple life. Most common diameter is 19mm and TC life of up to 8 months is achieved with type N sensor calibration. Life, however, is largely dependent on furnace technology, operating philosophy, fuel used, etc.
The trend worldwide appears to be to use 253MA tube as a protection sheath for placement in the packing coke to measure anode temperatures.
We can offer various configurations, some of which include:
Due to the harsh environment and various work practices, anode thermocouple life is an ongoing challenge. We are constantly testing new materials in the search for a more economic solution. Watch this space!
TMS has, together with one of the smelter customers, developed a burner nozzle for use on the bake furnace flue wall firing system.
Refurbishment of nozzles, together with the fact that the life achieved is up to 36 months, make this nozzle very cost effective. From a safety point of view, it totally eliminates the need to drill out blocked, red-hot nozzles on the furnace.
This clever design allows for cooling of the nozzle by allowing air through strategically placed suction holes, whilst at the same time aiding more efficient combustion, leading to significant fuel savings.