Sidewall eddy current monitoring of molten metal level and proximity in pyrometallurgical furnaces

为了优化何时和多长时间进行攻丝操作，需要准确了解火法冶炼炉中的熔融金属水平。此外，从炉膛侧壁测量熔金属的接近程度，可以提供剩余耐火壁的估计，这是炉膛长期结构完整性的重要指标。这项工作将重点关注开发一种新型电磁场传感系统的挑战，该系统可用于远程监测火法冶炼炉内熔融金属的水平和接近程度。这种能力目前还没有被现有的、商业上可用的检查系统所解决。该项目使用的技术将是涡流技术，该技术已经证明了其在各种应用中执行更远距离检测的能力，例如金属探测。该建议是我们之前使用涡流技术的实验工作的扩展，该技术证明了在模拟火法炉条件下检测熔融金属液位并结合对金属接近度的敏感性的可行性。这一阶段工作的主要重点是解决从测量的涡流信号中分离和报告两个关键工艺参数（金属液位和金属距离）所需的信号处理。按照第一阶段使用的方法，这项工作将涉及计算机建模和在实验室环境中使用实际线圈进行测试。最终的目标是建立一个在实际熔炉中进行测试的原型。这将需要优化参数，如线圈几何形状、线圈间距和到熔融金属浴的初始距离。此外，还有其他参数也会影响测量结果，例如高温、接近其他金属导体以及实际炉中的背景噪声，这些都需要探索。

Accurate knowledge of molten metal levels in pyrometallurgical furnaces is desired in order to optimize when and for how long tapping operations should be performed. In addition, proximity of molten metal, as measured from the furnace side wall, can provide an estimate of remaining refractory wall, an important gauge of the furnace's long term structural integrity. This work will focus on challenges to develop a novel electromagnetic field sensing system that could be used to remotely monitor the level and proximity of molten metal inside a pyrometallurgical furnace. This capability is not presently addressed by existing, commercially available, inspection systems. The technology used for this project will be eddy current based, which has demonstrated its capability to perform inspection at larger distances for various applications, such as metal detection. This proposal is an extension of our previous experimental work using eddy current based technology, which demonstrated the feasibility of detecting molten metal level combined with sensitivity to metal proximity under simulated pyrometallurgical furnace conditions. The main focus of this phase of work is to address the signal processing required to separate and report the two key desired process parameters, metal level and metal distance, from the measured eddy current signals. Following the approach used in the first phase, the work will involve computer modelling and tests using actual coils in a laboratory setting. The eventual target is to build a prototype for testing in an actual furnace. This will require optimization of parameters, such as coil geometry, coil spacing and initial distance to molten metal bath. In addition, there are other parameters, which can affect the measurements, such as high temperature, proximity of other metal conductors and background noise in an actual furnace, which need to be explored.