(1. 北京科技大學(xué) 土木與資源工程學(xué)院，北京 100083；
2. 金屬礦山高效開采與安全教育部重點(diǎn)實(shí)驗(yàn)室，北京 100083)
摘 要: 以謙比希銅礦的尾砂作為試驗(yàn)樣品，對質(zhì)量分?jǐn)?shù)為64%~73%的尾砂漿體進(jìn)行流變試驗(yàn)，研究其流變特性，預(yù)測該礦膏體的臨界濃度。傳統(tǒng)測量方法認(rèn)為流動性指數(shù)為1時(shí)的料漿濃度即為臨界濃度，試驗(yàn)發(fā)現(xiàn)，該方案得到的數(shù)值較為保守。研究料漿濃度與其屈服應(yīng)力之間的關(guān)系，發(fā)現(xiàn)兩者呈顯著的DoseResp函數(shù)關(guān)系，為精確預(yù)測料漿特性提供有效方法。得到屈服應(yīng)力隨料漿濃度變化的演化規(guī)律，基于屈服應(yīng)力增長速率，演化分為兩個(gè)階段：單調(diào)遞增階段和單調(diào)遞減階段。屈服應(yīng)力在濃度變化范圍內(nèi)具有極大值和極小值，可以通過DoseResp函數(shù)精確預(yù)測，而屈服應(yīng)力變化速率的“極大值點(diǎn)”即為“臨界濃度”。因此，確定謙比希銅礦膏體臨界濃度為70.73%，與試驗(yàn)結(jié)果吻合。
關(guān)鍵字: 尾砂；流變學(xué)；臨界濃度；屈服應(yīng)力；演化規(guī)律
（1. School of Civil and Resources 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）
Abstract:The rheological experiments on slurries with mass fraction of 64% to 73% were implemented using tailings from Chambishi Copper Mine to study the rheology and determine critical concentration of paste tailings. Previous studies thought the critical concentration was determined when value n is 1. However, recent experiments show that method underestimates critical concentration of paste tailings. The relationship between slurry concentration and yield stress through investigation, which accurately predicts slurry characteristics, is found with function DoseResp fitting. The evolution law of yield stress in paste tailings consists of two stages. The growth rate of yield stress increases in former stage but decreases in the later. Besides, maximum and minimum yield stress exist. The critical concentration is confirmed as maximum growth rate of yield stress emerges. Hence, the critical concentration of paste tailings from Chambishi Copper Mine is 70.73%, which coincides with experiment results.
Key words: tailings; rheology; critical concentration; yield stress; evolution law
