(1. 北京科技大学 土木与资源工程学院，北京 100083；
2. 金属矿山高效开采与安全教育部重点试验室，北京 100083；
3. 贵州川恒化工股份有限公司，福泉 550500)
摘 要: 针对二水磷石膏充填存在充填成本高、水泥耗量大、固结体强度低等问题，以半水磷石膏替代胶凝材料，通过正交试验法确定半水磷石膏充填的最佳配方，并对其流动性和微观结构进行研究。结果表明：通过配方优化，半水磷石膏充填体3 d、7 d、28 d的强度可达到5.4 MPa、5.5 MPa、6.1 MPa，膏体坍落度为26 cm，扩展度为71 cm。半水磷石膏充填配比中的3个影响因素为外加剂掺量、尾砂掺量和浆料浓度。对于3 d抗压强度影响最大的因素是外加剂掺量，对于7 d强度影响最大的因素是浆料浓度，对于28 d强度影响最大的因素是外加剂掺量，对于料浆流动性影响最大的是浆料浓度。半水磷石膏固结体由半水相转化为二水相，形成致密的晶体结构，表明以半水磷石膏制备的膏体料浆具备矿山充填的可行性。充填材料固体中废弃物用量占98%以上，成本较低，具有良好的经济效益和社会效益，推广应用前景良好。
关键字: 膏体充填；半水磷石膏；正交试验；微观结构；固体废弃物
（1. School of Civil and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China;
2. Key Laboratory of High-efficient Mining and Safety of Metal Mines, Ministry of Education, Beijing 100083, China;
3. Guizhou Chanhen Chemical Corporation, Fuquan 550500, China）
Abstract:In view of a series of dehydrate phosphogypsum filling problems, such as high filling cost, large consumption amount of cement, low strength of consolidation and so on, hemihydrate phosphogypsum was used as paste filling material in the paste filling research. Through orthogonal experiment method, the best prescription of hemihydrate phosphogypsum was determined, and the liquidity and micro structure were also studied. The results show that the filling strength of hemihydrate phosphogypsum in 3rd day, 7th day and 28th day can reach to 5.4 MPa, 5.5 MPa and 6.1 MPa, respectively, and the paste collapsbillity is 26 cm, and the extension is 71 cm. The three factors that affect the filling ratio of hemihydrate phosphogypsum are admixture amount, slurry concentration and tailing amount. The most influential factor that affects the compressive strength of sample for 3rd day is the admixture amount. The most influential factor that affects the compressive strength of sample for 7th day is the slurry concentration. The most influential factor that affects the compressive strength of sample for 28th day is the admixture amount. The most influential factor that affects the slurry fluidity is the slurry concentration. Meanwhile, the hemihydrate phosphogypsum consolidation transforms from hemihydrate into dehydrate, then forms dense crystal structure and effectively solidifies the soluble phosphorus. Therefore, the paste slurry made with hemihydrate phosphogypsum can completely meet the requirement of filling process and performance index. Furthermore, the solid waste in the filling material accounts for more than 98%, and the cost is low, which has good economic and social benefits, also the popularization and application prospects are good and worth expecting.
Key words: paste filling material; hemihydrate phosphogypsum; orthogonal test; micro structure; solid waste
