【Daily Question】Chemical Engineering Principles 198: Multi-stage Countercurrent Extraction (October 10)
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This post was last edited by Zaihui Kangqiao on 2015-11-2 at 14:57. The Chemical Engineering Theory section is launching a \"One Question per Day\" activity starting today, aimed at helping everyone reinforce their basic knowledge in chemical engineering. Subsequent series will include those on \"Principles of Chemical Engineering\", \"Mass Transfer and Separation\", \"Thermodynamics in Chemical Engineering\", and \"Chemical Process Engineering\". We hope for your active support! Answers to the questions in the \"One Question per Day\" activity can be viewed directly, and the thread will be closed after 1 day! ! Participation earns 3 wealth points, with an additional 3 wealth points awarded for correct answers~~~ Short answer question: Explain how the theoretical number of stages is determined in multi-stage counter-current extraction First, draw the solubility curve and auxiliary curves on the triangular phase diagram ； Second, based on the production requirements, determine the composition point F of the feed solution, the composition point of the final raffinate phase, and the solvent point S, using the lever rule ； Third, the extended lines of F and S intersect at this operation point ； Fourth, extend to intersect at point ; after finding , extend to intersect at point ； And so on, until the composition of the final raffinate phase is less than this value. The number of connection lines made constitutes the theoretical series sought.
Describe how the theoretical number of stages is determined for multi-stage counter-current extraction operations First, draw the solubility curve and auxiliary curves on the triangular phase diagram ； Second, based on the production requirements, determine the composition point F of the feed solution, the composition point Rn of the final raffinate phase, and the solvent point S; then use the lever rule to find E1 ； Third, the operation of connecting the extended lines of FE1 and RnS intersects at point O ； Fourth, extend OR1 to intersect at point E2; after finding R2, extend OR2 to intersect at point E3 ； And so on, until the composition of the final raffinate phase is less than Rn. The number of connection lines made constitutes the theoretical series sought.
By alternately using equilibrium lines (i.e., phase equilibrium relationships) and operation lines (i.e., material balance relationships), until the composition of the solute in the raffinate phase obtained from a certain equilibrium line equals the specified final raffinate phase composition XN, the number of equilibrium lines drawn on the triangular phase diagram represents the theoretical number of stages required for a multi-stage counter-current extraction process
First, draw the solubility curve and auxiliary curves on the triangular phase diagram； Second, based on the production requirements, determine the composition point F of the feed solution, the composition point Rn of the final raffinate phase, and the solvent point S; then use the lever rule to find E1 ； Third, the extended lines of FE1 and RnS intersect at point ?, which is the operation point ； Fourth, extend ?R1 to intersect at point E2; after finding R2, extend ?R2 to intersect at point E3 ； And so on, until the composition of the final raffinate phase is less than Rn. The number of connection lines made constitutes the theoretical series sought.
Describe how the theoretical number of stages is determined for multi-stage counter-current extraction operations Answer: First, draw the solubility curve and auxiliary curves on the triangular phase diagram ； Second, based on the production requirements, determine the composition point F of the feed solution, the composition point Rn of the final raffinate phase, and the solvent point S; then use the lever rule to find E1 ； Third, the extended lines of FE1 and RnS intersect at point ?, which is the operation point ； Fourth, extend ?R1 to intersect at point E2; once R2 is identified, extend ?R2 to intersect at point E3 ； And so on, until the composition of the final raffinate phase is less than Rn. The number of connection lines made constitutes the theoretical series sought.
First, draw the solubility curve and auxiliary curves on the triangular phase diagram； Second, based on the production requirements, determine the composition point F of the feed solution, the composition point nR of the final raffinate phase, and the solvent point S; then use the lever rule to find 1E ； Third, the operation of connecting the extended lines of F1E and nRS intersects at point ； Fourth, extend 1R to intersect at point 2E; after finding 2R, extend 2R to intersect at point 3E ； And so on, until the composition of the final raffinate phase is less than nR. The number of connection lines made constitutes the theoretical series sought.
First, draw the solubility curve and auxiliary curves on the triangular phase diagram； Second, based on the production requirements, determine the composition point F of the feed solution, the composition point Rn of the final raffinate phase, and the solvent point S; then use the lever rule to find E1 ； Third, the extended lines of FE1 and RnS intersect at point ?, which is the operation point ； Fourth, extend ?R1 to intersect at point E2; once R2 is identified, extend ?R2 to intersect at point E3 ； And so on, until the composition of the final raffinate phase is less than Rn. The number of connection lines made constitutes the theoretical series sought.
First, draw the solubility curve and auxiliary curves on the triangular phase diagram； Second, based on the production requirements, determine the composition point F of the feed solution, the composition point Rn of the final raffinate phase, and the solvent point S; then use the lever rule to find E1 ； Third, the extended lines of FE1 and RnS intersect at this operation point ； Fourth, extend R1 to intersect at point E2; once R2 is found, extend R2 to intersect at point E3 ； And so on, until the composition of the final raffinate phase is less than Rn. The number of connection lines made constitutes the theoretical series sought.
First, draw the solubility curve and auxiliary curves on the triangular phase diagram； Second, based on the production requirements, determine the composition point F of the feed solution, the composition point nR of the final raffinate phase, and the solvent point S; then use the lever rule to find 1E ； Third, the operation of connecting the extended lines of F1E and nRS intersects at point ； Fourth, extend 1R to intersect at point 2E; after finding 2R, extend 2R to intersect at point 3E ； And so on, until the composition of the final raffinate phase is less than nR. The number of connection lines made constitutes the theoretical series sought.
First, draw the solubility curve and auxiliary curves on the triangular phase diagram； Second, based on the production requirements, determine the composition point F of the feed solution, the composition point Rn of the final raffinate phase, and the solvent point S; then use the lever rule to find E1 ； Third, the extended lines of FE1 and RnS intersect at ? – this is the operation point ； Fourth, extend ?R1 to intersect at point E2; once R2 is identified, extend ?R2 to intersect at point E3 ； And so on, until the composition of the final raffinate phase is less than Rn. The number of connection lines made constitutes the theoretical series sought.
Generally, the drawing method is used, as it is simpler