Page 59 - Process simulation and control using Aspen

52 PROCESS SIMULATION AND CO NTROL USING ASPEN

TABLE 1.6
Component Flow rate (kmol/hr)
n -pentane 10
ethanol 3
water 7 5
.
Applying the NRTL property method , simulate the decanter block to compute
the flow rates of two product streams.
1 . 10 A ternary mixture having the following flow rates is fed to a separator (Sep2) at
50oC and 5 bar (see Table 1.7).
TABLE 1.7
Component Flow rate (kmol/hr)

n-pentane 33.623
ethanol 0 . 476
water 3 .705
To solve the present problem using Aspen Plus, the following specifications are
provided along with a T/F ratio of 0.905478 (see Table 1.8 and Figure 1.69).

TABLE 1.8
Component Split fraction in stream T
n-pentane 0 . 999
ethanol 0 . 9
water (calculated by Aspen)

B -O

FIGURE 1.69 A flowsheet of a separator.

Applying the SRK property method, simulate the flowsheet, shown in Figure 1.69,
and determine the product compositions.
1 .11 Repeat the above problem with replacing the separator Sep2 by Sep and using
split fraction of water 0.4 in Stream T.
1 .12 A dryer, as specified in Figure 1.70, operates at 200 oF and 1 atm. Apply the
SOLIDS base property method and simulate the dryer model (Flash2) to compute
the recovery of water in the top product.