从屈服应力角度完善膏体定义

Further development of paste definition from the viewpoint of yield tress

为了确定适合工业应用的膏体浓度范围，从屈服应力角度完善了膏体定义：以屈服应力为（200±25） Pa时料浆中固相的质量分数为恰饱和质量分数，反推饱和率为101.5%～105.3%时料浆中固相的质量分数范围，即为工业应用膏体浓度.采用不同矿山的两种尾矿（1^#尾矿和2^#尾矿）对膏体定义分别进行室内实验和工程验证.结果表明：1^#尾矿室内动态压密实验获得的底流中固相的最大质量分数为73.71%，膏体定义预测的理论膏体浓度最大值为73.89%，二者相差0.18%；2^#尾矿通过深锥浓密机获得底流中固相的最大质量分数为68%，膏体定义预测的理论膏体浓度最大值为68.97%，二者相差0.97%.完善后的膏体定义对膏体浓度预测更可靠.

In order to determine the suitable concentration of paste for industrial application, a further development of paste definition was proposed from the viewpoint of yield stress. The slurry saturation concentration is defined at the yield stress of （200 ±25） Pa. The suitable concentration of paste for industrial application is the slurry concentration range at the saturation ratio of 101. 5% to 105. 3% by back-stepping. Two tailings samples （named as Tailings 1 and 2） from different mines were used to testify the paste definition. Tailing 1 was used in laboratory experiment and Tailing 2 for engineering verification. The results show that the maximum concentration of Tailing 1 is 73. 71% by indoor dynamic consolidation experiment, and the maximum concentration of theoretic prediction by the paste definition is 73. 89%, which has the difference of 0. 18% compared with the laboratory experiment. The maximum underflow concentration of Tailing 2 can reach 68% by a deep cone thickener of some mine, and the maximum concentration is 68. 97% by prediction of the paste definition, a 0. 97% discrepancy in comparison with the underflow of the actual thickener. Hence, the paste definition proposed in the paper has high reliability for predicting the concentration of paste.