Спрос на литиевые батареи стимулирует развитие технологий -Оборудование для литий-ионных аккумуляторов
A side effect of rising lithium demand is a trend of mining companies rushing to go public. “In the next few years, some companies will be on-line to extract lithium carbonate from spodumene ore, which is usually around 8% Li2O by weight. It is easy to start to meet demand,” said Jenike & Johanson (Tyngsboro, Mass; www. .jenike.com) project engineer Josh Marion said. This shock, combined with lithium's high value and its specific physical properties, underscores the importance of proper design at all stages of lithium processing - from initial mining all the way through to the final refining step. This is forcing processors to approach bulk solids handling in new ways when trying to achieve ideal benchmarks for product purity, particle size and density. “Many of the processing needs may be more like pharmaceutical production than conventional mineral processing. There are high demands on material quality from battery manufacturers, and without reliable solids handling, the required product consistency cannot be achieved,” explains Marion.(Lithium - Ion Battery Equipment)
Some of the major operational issues experienced by lithium processors include clumping, build-up and flow cessation. To extract lithium from spodumene ore after mining, the raw ore needs to go through a series of crushing and sizing steps to produce ore of the desired particle size. The concentrate is then sent to a concentration plant where it undergoes several drying, grinding, separation, dewatering and further size classification steps to produce spodumene concentrate. The concentrate then goes to a processing plant for calcination where various aqueous solutions, acids and other chemicals are added to extract different impurities such as iron, aluminum, silicon and magnesium. Finally, the wet cake is recrystallized and dried to a lithium hydroxide (LiOH) or lithium carbonate (Li2CO3) product. "Especially in the step where the lithium is in the wet cake, if you don't have enough dryers or if the processing equipment isn't designed to handle the slightly wet material, then you'll often build up lithium and lithium lumps throughout the plant. And, because of The hygroscopic nature of lithium salts, even if the material is dry, it may absorb moisture and cake," Marion said. He emphasized that attention to detail during the equipment design phase is critical to avoiding these bottlenecks and ensuring consistent product quality. "When selecting and designing equipment, it is critical to ensure that material properties at each stage of the process are considered," he added.
As LIB performance needs evolve, device manufacturers are developing new technologies to meet these needs. “Right now, the key parameters for lithium producers are purity and particle size,” said Ananta Islam, sales director for North America chemicals at GEA Group AG (Düsseldorf, Germany; www.gea.com). The presence of certain impurities directly affects battery performance, so lithium battery producers must follow a strict set of purity standards. Christian Melches, Senior Sales and Technical Manager at GEA, explains: “Users are looking for battery-grade products with extremely low levels of sodium, potassium, sulphur and heavy metals. Whether from brine materials commonly found in South America or spodumene, a typical lithium source in Canada and Australia Starting with the ore, these impurities are usually all present in considerable quantities. To address the purity issue, GEA offers crystallisation units (Figure 1) that can be used in combination to optimise purification.” The edge comes from knowing how to steer the process through the process itself to several crystals Another important consideration for a combined crystallizer is energy efficiency. One energy saving measure is the use of mechanical recompression of the crystallizer steam to generate the steam used to drive the process.
LiOH - currently the preferred form of lithium for most LIB manufacturers - requires an extremely precise particle size distribution, which requires specialized spray drying equipment. Teach explained that a typical particle size range for conventional spray drying may be 40-50 μm, but for LiOH processing, it is in the range of about 5-7 μm. To ensure material compliance, GEA developed and patented specific nozzles for lithium processing (Figure 2). "The Combi-Nozzle utilizes high-pressure nozzles and compressed air for secondary atomization to further reduce particle size," teaches. Lithium producers say smaller particle sizes are required to properly compact the powder, which directly affects LIB performance. According to the teaching, this special nozzle was developed based on the technology used by the pharmaceutical industry to spray dry particles for inhalable drugs that require very fine particles.