DEPRIESTER CHART WITH NPROPANOL PLUS
DEPRIESTER CHART WITH NPROPANOL SERIES

To conveniently put the mass balances in matrix form, renumber the column as shown in Figure 6-2. We will discuss only systems where K i = K i(T, p).Д¦.2 Component Mass Balances in Matrix Form If the K i depend on compositions, then compositions must be guessed and corrected before doing the temperature calculation. The energy balances are used last because they require values for x i,j, y i,j, and T j.ДЇigure 6-1 Flowchart for matrix calculation for multicomponent distillationДЇigure 6-1 is constructed for an ideal system where the K i depend only on temperature and pressure. Thus, temperatures are calculated using reasonable flow rate values. This procedure makes sense, since an accurate first guess of liquid and vapor flow rates can be made by assuming constant molal overflow (CMO). Temperatures are calculated and converged on first, and then new flow rates are determined.

The energy balance is used to calculate new flow rates. This procedure uses the equilibrium (bubble-point) calculations to determine new temperatures. The narrow-boiling or bubble-point procedure is shown in Figure 6-1.

DEPRIESTER CHART WITH NPROPANOL SERIES

For design problems, a good first guess of N and N F must be made (see Chapter 7), and then a series of simulation problems are solved to find the best design.Дistillation problems converge best if a narrow-boiling feed calculation is done instead of the wide-boiling feed calculation used for flash distillation in Chapter 2. This is then a simulation problem with distillate flow rate specified. The most convenient set of variables to specify are F, z i, T F, N, N F, p, T reflux, L/D, and D. The advantage of this approach is that even very difficult problems can be made to converge. Computer routines for simultaneous solution of these equations are easily written. Most of the equations can conveniently be written in matrix form. That is, all mass balances for component i are grouped and solved simultaneously, all energy balances are grouped and solved simultaneously, and so forth. The most common approach is to group and solve the equations by type, not stage-by-stage. (The physical operation is unchanged thus, the basic laws and the results are invariant.) What different calculation procedures do is rearrange the equations to enhance convergence, particularly when it is difficult to make a good first guess. The general behavior of multicomponent distillation columns (see Chapter 5) and the basic mass and energy balances and equilibrium relationships do not change when different calculation procedures are used. A relatively simple matrix approach using the Оё method of convergence will be outlined in this section. Details of these procedures are available in a variety of textbooks (Seader and Henley, 2006 Holland, 1981 King, 1980 and Smith, 1963). Since distillation is a very important separation technique, considerable effort has been spent in devising better calculation procedures. These methods are not restricted to cases where a good guess of compositions can be made.Д¦.1 Introduction to Matrix Solution for Multicomponent Distillation Because stage-by-stage calculations are restricted to problems where a good first guess of compositions can be made at some point in the column, matrix methods for multicomponent distillation will be used. Since multicomponent calculations are trial-and-error, it is convenient to do them on a computer.

DEPRIESTER CHART WITH NPROPANOL PLUS

Aspen Plus Troubleshooting Guide for SeparationsД¬hapter 6: Exact Calculation Procedures for Multicomponent Distillation

Chapter 17: Introduction to Adsorption, Chromatography, and Ion Exchange.

Chapter 16: Introduction to Membrane Separation Processes.

Chapter 14: Extraction of Partially Miscible Systems.

Chapter 13: Immiscible Extraction, Washing, Leaching, and Supercritical Extraction.

Chapter 11: Economics and Energy Conservation in Distillation.

Chapter 10: Staged and Packed Column Design.

Chapter 8: Introduction to Complex Distillation Methods.

Chapter 7: Approximate Shortcut Methods for Multicomponent Distillation.

Chapter 6: Exact Calculation Procedures for Multicomponent Distillation.

Chapter 5: Introduction to Multicomponent Distillation.

Chapter 4: Column Distillation: Internal Stage-by-Stage Balances.

Chapter 3: Introduction to Column Distillation.

Chapter 1: Introduction to Separation Process Engineering.Wankat Separation Process Engineering, Second Edition Chapter 6: Exact Calculation Procedures for Multicomponent Distillation by Phillip C.

Depriester chart with npropanol