(1. 中南大學 能源科學與工程學院,長沙 410083;
2. 中南大學 流程工業(yè)節(jié)能湖南省重點實驗室,長沙 410083;
3. 湖南株洲冶煉集團股份有限公司,株洲 412004)
摘 要: 基于Fluent軟件,采用標準的k−ε湍流模型、歐拉−歐拉多相流模型、多重參考系穩(wěn)態(tài)流動方法,對浸出槽內(nèi)固液兩相流動過程進行數(shù)值模擬研究,且采用示蹤劑法研究流體在槽內(nèi)停留時間的分布。將臨界離底懸浮轉(zhuǎn)速的數(shù)值模擬結(jié)果與Zwietering臨界轉(zhuǎn)速進行比較,兩者吻合較好,驗證模型的有效性。應用數(shù)值模擬方法研究槳葉離底高度、槳葉間距和阻尼板高度對槽內(nèi)固相濃度分布和浸出液平均停留時間的影響規(guī)律。結(jié)果表明:在一定范圍內(nèi),增大槳葉間距有利于固相分布均勻,延長浸出液的平均停留時間,從而促進固液相之間的傳質(zhì)擴散,當槳葉間距為2D(D為浸出槽直徑)時,效果較優(yōu);在一定范圍內(nèi),增大阻尼板高度有利于槽內(nèi)固相的上浮;在允許范圍內(nèi),降低槳葉離底高度有利于改善槽底沉積現(xiàn)象,增大浸出液的平均停留時間,當槳葉離底高度為0.3D時,效果較好。
關(guān)鍵字: 浸出槽;歐拉−歐拉多相流模型;多重參考系;固液兩相流;停留, 時間
(1. School of Energy Science and Engineering, Central South University, Changsha 410083, China;
2. Hunan Key Laboratory of Energy Conservation in Process Industry, Central South University, Changsha 410083, China;
3. Hunan Zhuzhou Smelting Group Co., Ltd., Zhuzhou 412004, China)
Abstract:Based on Fluent software, the solid-liquid two-phase flow field of mechanical stirred zinc leach tank was simulated with standard k−ε turbulence model, Eulerian-Eulerian multiphase model and multi-reference flame method of steady-state flow. The residence time distribution of fluid in the tank was calculated mainly by tracer method. The result of critical suspended impeller speed was compared with the Zwietering correlation and the feasibility of the model and method was verified. The influences of some parameters, such as the distances between two impellers, the height of baffle and the distance of impeller from bottom, on solid concentration distribution and the residence time distribution of fluid in the tank were studied. The following conclusions are obtained. The increase of the distances between two impellers within a certain range is helpful for the uniform distribution of solid phase and increases the mean residence time of fluid, which promotes the mass transfer and diffusion between solid and liquid. The optimal distance is 2D (D is the diameter of leaktank). Increasing the height of baffle is advantageous to the raise of solid phase. Lowering the distance of impeller from bottom can decrease the solid deposition at the bottom and increase the mean residence time of fluid. The appropriate distance is 0.3D.
Key words: leach tank; Eulerian-Eulerian multiphase model; multi-reference flame method; solid-liquid two-phase flow; residence time


