تعيين پارامترهاي عملياتي بهينه در مرحله دفع اورانيوم از فاز آلي ﴿تري اكتيل آمين﴾ به فاز آبي براي توليد كيك زرد با استفاده از يك ستون ضربه اي پر شده در مقياس نيمه صنعتي

چكيده انگليسي :

70Determination of Optimum Operating Parameters in the Stripping Stageof Uranium from Organic Phase Tri Octyl Amine to Aqueous Phase for Yellowcake Production by Using a Pilot Pulsed Packed Column Vahid Rafiei v rafiei@gmail com Date of Submission September 17 2013 Department of Chemical Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc language farsi Supervisor Seyyed Mohammad Ghoreishi ghoreshi@cc iut ac ir Seyyed Jaber Safdari jsafdari@aeoi org irAbstract Up to now nuclear energy comes from nuclear fission of the uranium Therefore uranium extraction is veryimportant Solvent extraction is one of the most important extraction methods which is widly used inproduction and processing of nuclear fuel and plays special role in the nuclear fuel cycle Liquid Liquidextraction is a method to separate compounds based on their relative solubilites in two different immiscibleliquids In the present study leach liquor from the Bandar Abbas yellowcake production plant was used asimpure aqueous solution of uranium resource and the stripping experiments were performed with sodiumcarbonate In this study first impunties elements in the uranium stripping were determined then theseelements in the aqueous solution were identified and amount of each element specially the uranium wasdetermined with ICP analysis In stripping process trioctylamine solvents containing uranium product ofthe extraction process that obtained in the purification of leach liquor solution is the dispersed phase ofpulse packed column and sodium carbonate solution is the continuous phase of column The effect ofconcentration of stripper the ratio of the organic to the aqueous phase and pulsation intensity the strippingof the uranium was investigated and optimal conditions for the stripping due to each factor was obtained One hundred gr lit of carbonate sodium solution volume ratio of organic phase to aqueous of 4 andpulsation intensity of 3 cm s was determined as the optimum state This project describes the results ofinvestigations carried out in a pulsed packed column on a pilot scale Pulsed packed column is one of theimportant equipment that is applied for liquid liquid extraction because of its high efficiency and lowrequired space in nuclear petrochemical and food industries The efficiency of liquid liquid extractors isprimarily dependent on the degree of turbulence imparted to the system and interfacial area available formass transfer The performance of this column can be improved by mechanical pulsation of the continuousphase Although pulsed columns use either sieve plate or packing most reported investigations have dealtwith the sieve plate type Studies are considered on the effect of operating variables on the flooding andholdup of a pulsed packed column The considered variables in experiments included pulsation intensity continuous phase flow dispersed phase flow phase ratio and pulsation intensity on flooding and holdupwere investigated Dispersed phase holdup is one of the most important variables for the design of pulsedextraction column The holdup is needed to calculate the interfacial area per unit volume and the absolutephase velocities Up to now no research h cadonsidered the effect of height on holdup in this type ofcolumn In this study the variation of the dispersed phase holdup with height was studied experimentally The results of experiments showed that with increasing pulse velocity dispersed and continuous flow rate flooding velocity will be decreased and with increasing pulse velocity dispersed and continuous flow rate dispersed phase holdup will be increased KeywordsLiquid Liquid Extraction Stripping Pulsed Packed Column Holdup Sodium Carbonate

رفيعي، وحيد

سديم كربنات , موجودي فاز پراكنده