膏体尾矿屈服应力检测及其优化  

Yield stress measurements and optimization of Paste tailings

作　　者：吴爱祥[1] 焦华喆[1] 王洪江[1] 李辉[1] 仪海豹[1] 刘晓辉[1] 刘斯忠[1] 

机构地区：[1]北京科技大学土木与环境工程学院,金属矿山高效开采与安全教育部重点实验室,北京100083

出　　处：《中南大学学报（自然科学版）》2013年第8期3370-3376,共7页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(50934002,51104011,51074013);长江学者和创新团队发展计划项目(IRT0950);低品位难处理黄金资源综合利用重点实验室开放基金资助项目

摘　　要：屈服应力是高浓度非牛顿膏体的关键流变参数,是管道输送系统设计的基础,但目前该参数的实验获取不准确。针对桨式流变仪操作方法不同带来的屈服应力检测结果差距较大的问题,引入塌落度屈服应力理论对上述差异进行检验和校正,从而得到较为准确的浆体屈服应力和仪器操作方法。首先用控制剪切应力法(CSS)和控制剪切速率法(CSR)操作桨式流变仪检测屈服应力,然后利用塌落度流变理论所得屈服应力对桨式屈服应力进行对比分析。研究结果表明:塌落度法所得结果为浆体的动态屈服应力,CSS法流变曲线回归所得的宾汉姆屈服应力为静态屈服应力,并推荐恒定剪切速率的CSR法所得动态屈服应力能够反映物料性质,且剪切速率越低(<0.05s 1),检测结果越准确。Yield stress is the key parameter of high concentration non-Newton Paste, and the fundament for pipeline system design. But presently the value obtained from experimental test is not precise. For the disunity between the values from different test methods, the slump theology theory was brought in for verifying and revising the disunity, furthermore more exact yield stress value was obtained and the operation method of rheometer was commended. Firstly, the samples＇ yield stress was tested with vane rheometer, which was operated by Controlled shear stress （CSS） model and Controlled shear rate （CSR） model. Secondly, the values were compared with slump test results from the slump rheology theory. At last, the more exact yield stress value and more rational operation could be obtain. The results show that the value test by slump is the dynamic yield stress of sample, and the Bingham yield stress extrapolated from the rheology behavior of the CSS model is the static yield stress of sample. The results suggest that the performance of sample can be charactered veraciously by the dynamic yield stress calculated by CSR model of constant shear rate. The lower shear rate （〈0.05 s-l）, the more accurate value will be obtained.

关 键 词：膏体尾矿 屈服应力 桨式流变仪 塌落度流变理论 检测方法 

分 类 号：O373[理学—流体力学] TD926[理学—力学]