شبیه سازی اختلاط ذرّات جامد در راکتور همزن دار نیمه‌صنعتی لیچینگ

نوع مقاله : علمی و پژوهشی

نویسندگان

• مهدی مزمل
• بابک حضرتی عظیم
• نیما صادقی

دانشگاه صنعتی سهند

10.22067/ma.v31i1.66875

چکیده

نحوه و سرعت اختلاط ذرّات یکی از متغیرهای مؤثر انحلال ذرّات جامد در محلول است. در پژوهش حاضر از یک نرم‌افزار رایانه­ای برای شبیه­سازی اختلاط ذرّات در یک راکتور همزن دار نیمه‌صنعتی استفاده‌شده است. سرعت همزن، چگالی پالپ، اندازه ذرّات و چگالی ذرّات جامد به‌عنوان متغیرهای تحت بررسی انتخاب شدند. تأثیر عوامل فوق بر سرعت حرکت ذرّات و انباشتگی ذرّات بررسی شد. سرعت همزن بر سرعت حرکت ذرّات تأثیر محسوسی داشته است ولی با افزایش نسبت جامد به محلول تغییر میانگین سرعت خطی ذرّات محدودتر است. افزایش ابعاد و چگالی ذرّات موجب کاهش سرعت حرکت ذرّات شده است. انباشتگی ذرّات با افزایش چگالی پالپ و اندازه ذرّات افزایش یافته است. سرعت همزن به‌طور محسوسی از مقدار مناطق بی‌اثر در راکتور کاسته است و چگالی ذرّات روی الگو انباشتگی بی‌تأثیر است.

کلیدواژه‌ها

• اختلاط
• راکتور همزن دار
• لیچینگ
• شبیه سازی

---

عنوان مقاله [English]

Simulation of Solid Particles Mixing in a Pilot Leaching Reactor

نویسندگان [English]

• .Mahdi .Mozammel
• Babak Hazrati Azim
• Nima Sadeghi

Sahand University of Technology

چکیده [English]

The mode and rate of agitation of the particles is one of the effective variables for dissolving solid particles in the aqueous solution. In the present study, a computer software has been used for simulation of the particle agitation in the pilot mixer reactor. The stirrer speed, pulp density, particle size and solid particles density were selected variables. The effect of above factors on velocity of particles and their accumulation was investigated. The stirrer speed has significant effect on the particle velocity, but by increasing the pulp density, average speed of the particles is more limited. Increasing the size and density of particles can reduce the speed of moving parts. Particle accumulation has increased with increasing pulp density and particle size. The stirrer speed significantly decreases the amount of inactive areas in the reactor. The density of particles does not effect on particle accumulation.

کلیدواژه‌ها [English]

• Mixing
• Leaching
• Agitating Reactor
• simulation

مراجع

1. Günkel, A. A. and Weber, M., E., "Flow phenomena in stirred tanks. Part I. The impeller stream", AIChE Journal, Vol. 21, pp. 931-939, (1975).

2. Harvey, P. S. and Greaves, M., "Turbulent flow in an agitated vessel. Part I: A predictive model", Transactions of the Institution of Chemical Engineers, Vol. 60, pp. 195-200, (1982).

3. Placek, J. and Tavlarides, L. L., "Turbulent Flow in Stirred Tanks", AIChE Journal, Vol. 31, pp. 1113–1120, (1986).

4. Pericieous, K. A. and Patel, M. K., "The source-sink approach in the modeling of stirred reactors", Phys Chem Hydrodynamics, Vol. 9, pp. 279-297, (1987).

5. Middleton, J. C., Pierce, F. and Lynch, P. M., "Computations of flow fields and complex reaction yield in turbulent stirred reactors, and comparison with experimental data", Chemical Engineering Research & Design, Vol. 64.1, pp. 18-22, (1986).

6. Brucato A., Ciofalo M., Grisafi F. and Micale G., "Numerical prediction of flow fields in baffled stirred vessels: a comparison of alternative modelling approaches", Chemical Engineering Science, Vol. 53, pp. 3653-3684, (1998).

7. Brucato A., Ciofalo M., Grisafi F. and Micale G., "Complete numerical simulation of flow fields in baffled stirred vessels: the inner-outer approach", Institute Of Chemical Engineers Symposium Series, Vol. 136, pp. 152-155, (1994).

8. Luo, J. Y. and Gosman, A. D., "Prediction of Impeller-Induced Flow in Mixing Vessels Using Multiple Frames of Reference", Institute of Chemical Engineers Symposium Series, Vol. 136, pp. 544-549, (1994).

9. Kasat, G. R., Khopkar, A. R., Ranade, V. V. and Pandit, A. B.," CFD simulation of liquid-phase mixing in solid–liquid stirred reactor", Chemical Engineering Science; Vol. 63, pp.3877-85, (2008).

10. Tamburini, A, Cipollina, A. and Micale, G. "CFD Simulation of Solid Liquid Suspensions in Baffled Stirred Vessels Below Complete Suspension Speed", Chemical Engineering, Vol. 24, pp. 1435-1440, (2010).

11. Derksen, J. J. “Highly resolved simulations of solids suspension in a small mixing tank”, AIChE Journal, Vol. 58, pp.3266-3278, (2012).

12. Tamburini, A, Cipollina, A, Micale, G, Brucato, A. and Ciofalo, M., "CFD prediction of solid particle distribution in baffled stirred vessels under partial to complete suspension conditions", Aidic Conference Series Journal, Vol. 11, pp. 391-400, (2013).

13. Tamburini, A., Cipollina, A., Micale, G., Brucato, A. and Ciofalo, M., "CFD simulations of dense solid–liquid suspensions in baffled stirred tanks: Prediction of suspension curves", Chemical Engineering Journal; Vol. 178, pp. 324-341, (2011).

14. Wadnerkar, D., Utikar, R. P., Tade, M. O. and Pareek, V. K., "CFD simulation of solid–liquid stirred tanks", Advanced Powder Technology; Vol. 23, pp. 445-453, (2012).