The Use of Sequestrants for the Removal of Calcium Salt Deposits from Stainless Steel Surfaces

摘要CTS-9905152 C。格兰特，NCSU这项研究将调查传质和表面反应的作用，在中性和碱性环境中使用螯合剂溶液从不锈钢表面去除钙矿物膜。 将使用三种类型的实验，范围从实验室到工业规模：（1）批溶出研究。 在这些实验中，通过将粉末颗粒悬浮在溶液中来研究矿物的溶解。 从传质的角度来看，该实验没有得到很好的表征，但它代表了文献中发现的溶解动力学的标准研究。(2)从旋转圆盘中溶解。 在这个实验中，钙矿物质的膜将沉积在不锈钢盘上。 通过在清洁溶液中连续旋转圆盘来去除薄膜。 该实验具有在膜的整个表面上均匀的良好表征的传质速率。 这将使我们能够隔离的溶解过程中的膜形态的表面演变的作用。(3)湍流管流中的溶解。 在这里，将量化典型条件下的清洁率。

AbstractCTS-9905152C. Grant, NCSUThis research will investigate the role of mass transfer and surface reactions on the removal of calcium mineral films from stainless steel surfaces using sequestrant solutions in neutral and alkaline environments. Three types of experiments will be used, that range from laboratory to industrial scale: (1) Batch dissolution studies. In these experiments the dissolution of the mineral is investigated by suspending powder particles in the solution. This experiment is not well-characterized from a mass transfer point of view, but it represents the standard study of dissolution kinetics found in the literature. (2) Dissolution from a rotating disk. In this experiment a film of calcium mineral will be deposited on a stainless steel disk. The film will be removed by continuously rotating the disk in the cleaning solution. This experiment has a well-characterized mass transfer rate that is uniform over the whole surface of the film. This will allow us to isolate the role of surface evolution of film morphology during the dissolution process. (3) Dissolution in turbulent pipe flow. Here the cleaning rates under typical conditions will be quantified.