COSINE-200 is the next phase of the ongoing COSINE-100 experiment. The main purpose of the experiment is the performance of an unambiguous verification of the annual modulation signals observed by the DAMA experiment. The success of the experiment critically depends on the production of a 200 kg array of ultra-pure NaI(Tl) crystal detectors that have lower backgrounds than the DAMA crystals. The purification of raw powder is the initial but important step toward the production of ultra-pure NaI(Tl) detectors. We have already demonstrated that fractional recrystallization from water solutions is an effective method for the removal of the problematic K and Pb elements. For the mass production of purified powder, a clean facility for the fractional recrystallization had been constructed at the Institute for Basic Science (IBS), Korea. Here, we report the design of the purification process, material recovery, and performance of the NaI powder purification facility.

中文翻译：

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用于 COSINE-200 实验的超纯 NaI 粉末的大规模生产设施

COSINE-200 是正在进行的 COSINE-100 实验的下一阶段。该实验的主要目的是对 DAMA 实验观察到的年度调制信号进行明确验证。实验的成功关键取决于 200 kg 超纯 NaI(Tl) 晶体探测器阵列的生产，这些探测器的背景比 DAMA 晶体低。原料粉末的纯化是生产超纯 NaI(Tl) 检测器的第一步，但也是重要的一步。我们已经证明，从水溶液中分步重结晶是去除有问题的 K 和 Pb 元素的有效方法。为了大规模生产纯化粉末，韩国基础科学研究所（IBS）建造了一个用于分级重结晶的清洁设施。这里，