Metso Insights Blog Mining and metals blog Outotec® MeltGuard – a first step to take operators out of harm’s way
Feb 19, 2018

Outotec® MeltGuard – a first step to take operators out of harm’s way

Taking bath measurements in a flash smelting or electric furnace typically requires different measuring rods to be manually lowered and lifted into the furnace through an opening in the roof. In the case of bath level measurements, the process operator then interprets the levels based on the different solidification rates of different phases, such as the metal and slag. This means that the measurement results can vary widely based on the individual operator’s expertise and experience. Most importantly, standing on the furnace roof while opening the measuring port during production poses an unnecessary safety risk – one which can be avoided with modern approaches such as Outotec MeltGuard.

Outotec MeltGuard automates the different bath measurements so that operators no longer need to be on the furnace roof during measurements and when the measuring port is open. Instead, the measurements are controlled from the local control panel, which can be located well away from the furnace roof. This setup allows the operator to monitor the measuring sequence and the performance of Outotec MeltGuard without standing near the open measuring port to manually operate the rods. Using servos with accurate encoders allows immersion to be controlled so that measurement is always carried out in the same way – meaning, for example, that temperature measurements can always be taken at the same spot inside the furnace. Utilizing a sophisticated machine-vision algorithm to provide the level measurement results ensures that the different levels are always detected from the sounding rod in the same way, providing consistently reliable results.

The system can also be installed with an optional liquidus measurement probe, which makes it possible to control the actual superheat of the slag instead of just controlling melt temperatures. Optimizing the slag superheat can also improve the campaign time of the furnace by reducing refractory wear and decreasing the heat gradient through the furnace walls. The system can also include an optical pyrometer, which removes the need for disposable temptips. Outotec MeltGuard’s optional 360-degree interior furnace camera allows the condition of the furnace to be systematically monitored, further ensuring safe operation.

Outotec MeltGuard’s measurement capabilities:

  • Melt levels
  • Melt temperatures using:
    • Standard temptip
    • Optional: slag liquidus temperature temptip
    • Optional: optical pyrometer
  • Optional: furnace interior wall profile and 360-degree camera