国外动态──旧砂再生新水平（一）文章分两部分，将世界上广为应用的旧砂再生工艺及设备加以介绍。为了减少废旧砂的抛弃，这些设备的需求激增。尤其过去认为仅化学粘结剂砂对环保有害，现在长期以来认为无害的湿模粘土砂也是需要处理的材料，这样增加了开发旧砂再生系统的动 Foreign Dynamic ─ ─ a new level of regeneration of old sand (A) The article is divided into two parts, the world’s most widely used sand regeneration technology and equipment to be introduced. In order to reduce discarded sand, the demand for these devices has surged. In the past, in particular, it was thought that only chemical binder sands are harmful to the environment and wet sand clay that has long been considered harmless is also a material that needs to be treated, thus adding to the need to develop an old sand recycling system