Column grand composite curves

A horizontal distance between the column grand composite curve pinch point and the vertical axis represents excess heat, and therefore the scope for reduction in reflux ratio. For smaller reflux ratios, the column grand composite curve will move toward the vertical axis, and hence reduce the reboiler and condenser duties, which may be estimated by... 

Example 4.31 Column grand composite curves in a distillation column with a five-component mixture The... 

Example 4.32 Column grand composite curves in methanol plant Table 4.16 describes the existing base case operations for columns 1 and 2 of the methanol plant obtained from the converged simulations using the RKS equation of state to estimate the vapor properties. The activity coefficient model, NRTL, and Henry components method are used for predicting the equilibrium and liquid properties. 

Column 1 has 51 stages, and operates with a partial condenser with a duty of 1.371 MW at the top, and a side condenser with a duty of 8.144 MW at stage 2. It has no reboiler however, it receives a side heat stream with a duty of 15.299 MW at the last stage from Section 2 of the plant. The column grand composite curves in... 

Figure 5.12. Column grand composite curves tor column 1 in Example 5.15 (a) temperature-enthalpy deficit curves and (b) stage-enthalpy deficit curves (Table 5.3 describes designs 1 and 2).

Using the following input summary for RADFRAC columns, construct the column grand composite curves and stage exergy profiles with the property methods of Peng-Robinson. Discuss the results. 

To analyze the energy-saving potential of distillation columns, it is customary to construct the temperature enthalpy and stage-enthalpy curves, called column grand composite curves. Column grand eomposite curves are based on the practical near-minimum thermodynamic condition approximation proposed by Dhole and... 

Example 4.24 Column grand composite curves in methanol plant... 

FIGURE 5.8 (a) Column grand composite curves for column 1 and (b) exergy loss profiles for column 1. 

There are several key opportunities for column optimization, which include reflux ratio improvement, pressure changes, feed preheating, side reboiling/condensing, and feed stage location. A pinch tool called a column grand composite curve (CGCC) (Dhole and Linnhoff, 1993) was developed to provide an aid for the evaluation of these improvements. 

FIGURE 11.6. Construction of column grand composite curve. 

The methodology for column heat integration is explained by Figure 13.8, which can be applied for new and retrofit designs. Let us explain the methodology step-by-step as below. The T-H plot is the column grand composite curve (CGCC), which is discussed in Chapter 11. 

The objective of this work is to simulate the depropanizer distillation column of the NGL plant to compare the costs of the conventional distillation with the cost of a heat pump distillation system. Using the column grand composite curves (CGCC) of the depropanizer distillation column, the depropanizer column is suitable for retrofitting by... 

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