Mini-pilot scale equipment
The SOLVOMET centre is continuously investing in mini-pilot scale equipment for solvent leaching and solvent extraction experiments, allowing to tackle upscaling issues (from the lab-scale to the mini-pilot scale level) and to assist in the development of novel, commercial solvometallurgical flow sheets. Upscaling questions that are investigated by the SOLVOMET centre include:
- How can the solid-liquid separation be done after leaching, especially in case of viscous liquids?;
- How can the solvent be recycled after leaching?;
- How can loss of solvent on the solid particles be minimised?
1. Mini-pilot scale solvent extraction studies
Batch solvent extraction processes can be scaled up to a mini-pilot scale in a continuous counter current mode in our mixer-settler set-up, with the final goal to examine the possibility of scaling up the process and/or producing larger volumes of purified metal solution. First, a flow sheet is designed to determine the number of stage and optimal aqueous-to-organic phase ratio of extraction, scrubbing and stripping based on McCabe-Thiele diagrams. Furthermore, the kinetics are fully examined. Next, the process will be run in the mixer-settlers. The flow rates of each stage will be controlled to have the required aqueous-to-organic phase ratio. Samples of each stage will be taken on a regular basis to evaluate the performance and make adjustments if necessary.
SX Battery 1 (MEAB)
The mixer settler set-up of MEAB consists of 12 stages in total, which can be combined into an extraction, scrubbing and stripping step according to the objected flow sheet of the solvent extraction process. The mixer settlers are made of PVDF and can be used at room temperature (heating is not possible). The volume of the settler chamber is 1 L and a total flow rate up to 10 L/min can be achieved.
SX Battery 2 (Rousselet)
The mixer settler set-up of Rousselet Robatel consists of 12 stages, that can be heated up to 80 °C using a circulating water bath. The stages are each isolated and made of PVDF. The volume of the mixer chamber and settler chamber in each stage are 35 mL and 143 mL, respectively. The total flow rate can reach up to 6 L/h, with a motor speed up to 1500 rpm.
2. Solvent leaching studies
The SOLVOMET centre has obtained funding to invest in mini-pilot leaching equipment. This equipment will include:
- A jacketed reactor platform for temperature controlled batch leaching, with different reaction vessels (1 L and 5 L vessels, see image), optimised for use with viscous liquids (e.g. ionic liquids), with PC control software for automation of reaction parameters.
- Pressurised column leaching setup. A setup used for preparative medium-pressure liquid chromatography (MPLC) will be transformed into a setup for solvometalllurgical column leaching at pressures up to 50 bar. Glass columns of different diameters and lengths will be used.