# Development and Application of an Optoelectronic Sensor for Flame Monitoring of a Copper Concentrate Flash Burner

## TL;DR

A new optoelectronic sensor was developed to monitor flame conditions in copper smelting, enabling real-time control and improved efficiency.

## Contribution

The development of a non-invasive, real-time optoelectronic sensor for flame monitoring in copper flash smelting.

## Key findings

- The sensor successfully captured flame temperature, radiation, and flickering dynamics in industrial conditions.
- Fourier-based analysis revealed low-frequency oscillations and instability events in the combustion process.
- The sensor system provides a flame instability index to assess combustion quality in real time.

## Abstract

What are the main findings?
The developed optoelectronic prototype, using a VIS-NIR spectrometer and high-temperature optical fiber, successfully captured key combustion parameters—including total radiation, flame temperature, and flickering dynamics—under real industrial conditions in a copper flash smelting furnace.Fourier-based analysis, including STFT, revealed intrinsic low-frequency oscillations and instability events, clearly characterizing the pulsating behavior and combustion anomalies of the FSF burner.

The developed optoelectronic prototype, using a VIS-NIR spectrometer and high-temperature optical fiber, successfully captured key combustion parameters—including total radiation, flame temperature, and flickering dynamics—under real industrial conditions in a copper flash smelting furnace.

Fourier-based analysis, including STFT, revealed intrinsic low-frequency oscillations and instability events, clearly characterizing the pulsating behavior and combustion anomalies of the FSF burner.

What is the implication of the main finding?
The integrated sensing system offers a robust, non-invasive, and real-time diagnostic tool that enhances the operational control and efficiency of copper pyrometallurgy.Detailed insights into flame dynamics provided by the sensor will pave the way for the development of automated control strategies and predictive maintenance in industrial smelting operations.

The integrated sensing system offers a robust, non-invasive, and real-time diagnostic tool that enhances the operational control and efficiency of copper pyrometallurgy.

Detailed insights into flame dynamics provided by the sensor will pave the way for the development of automated control strategies and predictive maintenance in industrial smelting operations.

A flash smelting furnace operation is based on the exothermic reduction of copper concentrates in the combustion shaft, and these reactions occur at high temperatures (1250–1350 °C), where flame control is fundamental to optimizing copper reduction. Furthermore, inherent physicochemical reactions of the reduction process have been shown to emit spectral lines in the visible-near infrared spectrum (250–900 nm). Thus, an optoelectronic sensor prototype is proposed and developed for flame measurements of an industrial copper concentrate flash smelting furnace. The sensor system is composed of a high-temperature optical fiber probe, which functions as a waveguide to capture the emitted flame radiation and a visible-near infrared spectrometer. From the measured radiation, flame temperature and flame dynamics are analyzed. Flame temperature is estimated using the two-wavelength temperature estimation method, and flame dynamics are defined as variations in the total emissive power, which are studied in the time and frequency domain via the Fourier Transform method. These combustion dynamics are then used to create a flame instability index, which is used to characterize the flame combustion quality. The combination of this index and sensor platform provides a powerful tool to aid in proper flame control.