Zanetti Maria Chiara, Fiore Silvia
Department of Georesources and Territory, Politecnico di Torino, Italy.
Waste Manag Res. 2003 Jun;21(3):235-42. doi: 10.1177/0734242X0302100307.
An industrial treatment was performed by the Sasil plant of Brusnengo (Biella, Northern Italy), which is part of the Gruppo Minerali S.p.A. (Novara, Northern Italy), to consider the reclamation of bentonite bonded moulding sands obtained from the Teksid Italia S.p.A. cast iron foundry plant in Crescentino (Vercelli, Northern Italy). An evaluation of the fine particles produced by the wet-mechanical regeneration treatment was made with the purpose of proposing their recycling as binding agents in moulding operations in the cast iron foundry and for the production of tiles in the ceramic industry. The pre-mixed product sold by bentonite suppliers (35% coal dust and 65% bentonite, 0.15 Euro/kg) could be made from the recovered fine fraction below 0.025 mm with the addition of active clay and coal dust, thus obtaining a product that will have physico-chemical properties similar to those of calcic bentonite. The improvements due to the addition of the fine particles to the usually employed clay for tile production were also underlined from the results of several baking tests. The recovery and recycling of sands and fine particles obtained from the reclamation of bentonite moulding sands will lead to a saving of raw materials and landfill space, with economic and environmental advantages.
位于布鲁斯内戈（意大利北部比耶拉省）的萨西尔工厂进行了一项工业处理，该工厂是Gruppo Minerali S.p.A.（意大利北部诺瓦拉省）的一部分，目的是考虑回收从位于克雷申蒂诺（意大利北部韦尔切利省）的泰克西德意大利股份公司铸铁铸造厂获得的膨润土粘结型砂。对湿机械再生处理产生的细颗粒进行了评估，目的是提议将其作为铸铁铸造厂造型作业中的粘结剂以及陶瓷工业瓷砖生产中的粘结剂进行回收利用。膨润土供应商出售的预混产品（35%煤粉和65%膨润土，0.15欧元/千克）可以由回收的小于0.025毫米的细颗粒与活性粘土和煤粉混合制成，从而获得一种物理化学性质与钙基膨润土相似的产品。几次焙烧试验的结果也突出了在通常用于瓷砖生产的粘土中添加细颗粒所带来的改进。从膨润土型砂回收中获得的砂和细颗粒的回收与再利用将节省原材料和填埋空间，具有经济和环境优势。
