New sensors in pressure hydrometallurgy

随着全球对原材料的需求不断增加，加拿大金属行业正在扩张，并在世界各地投资新项目。加压湿法冶金是一种从矿石和精矿中回收金属的技术，它利用水介质中的高温和压力。它已经成为金属行业非常有吸引力的选择，因为它提供了几个比常压工艺更好的优势。目前的研究方案是一项持续的努力，重点是与加压湿法冶金过程直接相关的高温(100-300oC)浓缩电解液系统的理论进展和实验应用。由于这些过程中的化学反应发生得非常快，通常是在腐蚀性很强的环境中，并且在固体矿物颗粒的存在下，因此非常需要开发坚固耐用的传感器来在线测量关键过程变量，并对过程进行监测和控制。目前的研究方案旨在开发新的仪器和新的化学传感器，这些仪器和传感器将在工艺条件下在线工作。我们已经证明了一种基于电导的传感器能够监测腐蚀性泥浆中游离酸浓度的原理。我们还对最初为核电行业制造的陶瓷膜电极进行了改装，以适应湿法冶金行业的需要。再加上我们对高温水体系的同步化学建模和模拟研究，我们将这些传感器从实验室的成功转化为工业工具。为此，我们将开发无电极电导传感器在高温浆料系统中的应用。我们还将通过实施金属/金属氧化物电极来克服陶瓷膜电极的脆弱性。我们将测试和开发新的传感器来测量氧化还原电位。该项目将培训研究生和本科生/暑期学生在困难的实验条件下应用复杂的电化学技术。这项工作通过产生技术，使金属生产商在全球市场上更具竞争力，以满足未来几年对初级金属的需求，从而为加拿大经济做出贡献。

With increasing global demand for raw materials, the Canadian metals industry is expanding and investing in new projects around the world. Pressure Hydrometallurgy is a technology used for metal recovery from ores and concentrates that employs high temperatures and pressures on aqueous media. It has become a very attractive option in the metals industry as it offers several advantages over atmospheric processes. The present research programme constitutes an on-going effort that focuses on theoretical advances and experimental applications of high-temperature (100-300oC) concentrated electrolyte systems directly related to pressure hydrometallurgical processes. Because chemical reactions in these processes occur very fast, often under very corrosive environments, and in the presence of solid mineral particles, there is a great need to develop robust sensors that can measure key process variables on line and effect process monitoring and control. The present research programme, aims at developing novel instrumentation and new chemical sensors that will work on-line and at process conditions. We have already proven the principle of a conductivity-based sensor capable of monitoring free acid concentration in corrosive slurries. We have also adapted a ceramic membrane electrode that was originally built for the nuclear power industry to the needs of the Hydrometallurgical industry. Coupled with our concurrent chemical modelling and simulation studies on high temperature aqueous systems, we convert these sensors from laboratory successes into industrial tools. To do so, we will develop the use of electrodeless conductivity sensors in high temperature slurry systems. We will also overcome the fragility of the ceramic membrane electrode by implementing metal/metal oxide electrodes. We will test and develop new sensors to measure REDOX potential. The project will train graduate and undergraduate/summer students in sophisticated electrochemical techniques applied under difficult experimental conditions. This work contributes to the Canadian economy by generating technology that renders metal producers more competitive in the global markets to satisfy the demand for primary metals in the years ahead.