Experimental study on optimal operation of an actual-size batch crystallizer

实型间歇式结晶器优化运行试验研究

基本信息

批准号：
09555234
负责人：
NORIAKI Kubota
金额：
$ 6.53万
依托单位：
IWATE UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1999
项目状态：
已结题

项目摘要

Batch crystallization can be used for the production of a variety of fine chemicals in small scale. It has flexibility in operation. But, the method for control of crystal size, which has been long desired has not be established yet. In this research project, the effect of seeding on the product crystal size distribution was investigated experimentally using both large and small scale batch cooling crystallizers. The aim of this research was to establish the method for crystal size control. Experimental work was made with the potassium alum system. As a cooling mode, quenching (natural cooling) method was mainly employed. For comparison, the other methods, linear and controlled cooling methods, were also tested.At first, a small scale crystallizer (12 L) was used to investigate the effect of seed amount and initial solution concentration on the crystal size distribution of product. The size distribution of product crystals has been found to become uni-modal under the condition of enoug … More h seeding over a critical seed concentration. Under this condition, the product crystals were all grown seeds. The same result was obtained for solutions for high initial concentration. Even for the large scale crystallizer (600L) used, the uni-modal crystal size distribution was confirmed similarly to be obtained under the condition of enough seeding.In addition to the above experiments, the generation rate of fine crystals was measured to clarify the mechanism for the seeding effect on the production of uni-modal size distribution. Agglomeration (or sticking) of fine crystals to seed crystals and the short period of high supersaturation were shown to play important roles. By comparing the quenching method with the other cooling modes, the cooling mode itself was shown not to be an important factor in producing crystals of uni-modal size distribution. 'It is the seed amount that plays an important role.The results obtained in this project is expected to be extended to a useful and practical design method of a batch crystallizer for the production of the crystals of controlled size. Part of the results obtained in this project have been published in international journals (5 papers) and presented in meetings and symposia (1 6 papers). Less

批处理结晶可用于小规模生产各种精细化学物质。它具有灵活性。但是，尚未确定控制晶体大小的控制方法。在该研究项目中，使用大型和小型批处理冷却结晶器对播种对产物晶体尺寸分布的影响进行了研究。这项研究的目的是建立晶体尺寸控制的方法。实验性工作是用钾校友系统进行的。作为冷却模式，主要采用了淬火（自然冷却）方法。为了进行比较，还测试了其他方法，线性和受控的冷却方法。首先，使用小型结晶器（12 L）来研究种子量和初始溶液浓度对产品晶体尺寸分布的影响。已经发现，在索格的条件下，产品晶体的尺寸分布已成为单模式……在临界种子浓度上更多的h播种。在这种情况下，产物晶体都是生长的种子。对于高初始浓度的溶液，获得了相同的结果。即使对于所使用的大型结晶剂（600L），同样确认单模式晶体尺寸分布以在足够的播种条件下获得。在上述实验的情况下，还测量了细晶体的生成速率，以阐明对播种对单型模式尺寸分布产生的播种作用的机制。细晶体的聚集（或粘在种子晶体上）和高过饱和的短期发挥着重要作用。通过将淬火方法与其他冷却模式进行比较，冷却模式本身并不是产生单模式尺寸分布晶体的重要因素。 '是种子数量起着重要作用。预计该项目中获得的结果将扩展到用于生产受控尺寸晶体的批处理结晶器的有用且实用的设计方法。该项目获得的部分结果已在国际期刊（5篇论文）中发表，并在会议和座谈会（1 6篇论文）中发表。较少的