Distillation Design Questions and Answers Part-19

1. The 2N Newton method is based on algorithm of?
a) N X N
b) 2 X N
c) N X M
d) 2 X M

Answer: b
Explanation: The 2N Newton method is based on algorithm of 2 X N, while N X N is called as the Jacobin matrix.

2. XIJ and Yij are the component balances of
a) Equilibrium relation
b) Constant relation
c) Final relation
d) Direct relation

Answer: a
Explanation: XIJ and Yij are the component balances of Equilibrium relation, Whereas X=Y represents the final relation of the system

3. Which method uses the summation of the equations for vapor and liquid components?
a) NR Method
b) RF Method
c) Tomich Method
d) 2N Method

Answer: d
Explanation: Tomich Method uses the summation of the equations for vapor and liquid components, while RF and NR are based on the initial conditions of column.

4. The independent variables of independent functions are used as, Fi =
a) [E1 E2 E3 …. EN-1 EN, K1 K2 K3 …. KN-1 KN].
b) [T1 T2 T3 …. TN-1 TN, K1 K2 K3 …. KN-1 KN].
c) [S1 S2 S3 …. SN-1 SN, E1 E2 E3 …. EN-1 EN].
d) [K1 K2 K3 …. KN-1 KN, T1 T2 T3 …. TN-1 TN].

Answer: c
Explanation: As Fi= [S1 S2 S3 …. SN-1 SN, E1 E2 E3 …. EN-1 EN] T , where S is the same factor as used in Fenske’s equation and E are the respective energy of the systems.

5. The stages flow rate and the vapor flow rates are expressed, as
a) [E1 E2 E3 …. EN-1 EN, V1 V2 K3 …. VN-1 VN]
b) [T1 T2 T3 …. TN-1 TN, V1 V2 V3 …. VN-1 VN].
c) [S1 S2 S3 …. SN-1 SN, E1 E2 E3 …. EN-1 EN].
d) [K1 K2 K3 …. KN-1 KN, T1 T2 T3 …. TN-1 TN].

Answer: b
Explanation: As Xi= [T1 T2 T3 …. TN-1 TN, V1 V2 V3 …. VN-1 VN] T, where T is defined as respective temperature and the volume V corresponding to the same relation.

6. The initial assumption to Tomich method is
a) Set initial Temperature
b) Set total stages
c) Final Pressure
d) Initial Pressure

Answer: a
Explanation: The initial assumption to Tomich method is to set initial Temperature for each stage, for any other method feed rates and total mole balance are assumed.

7. The θj factor is a
a) Subtracted
b) Additive
c) Multiplier
d) Divider

Answer: c
Explanation: As |L/V| = θj*|Lj/Vj|CR and θj factor is a Multiplier, this is based on a correlation that acts as a correction factor of the calculation.

8. Newton’s method is a fixed point iteration method, As Pn
a) g(Pn-1)
b) (Pn-1)
c) g
d) Pn

Answer: a
Explanation: Always Pn = g (Pn-1) is fixed point as in newton method, while other method NR and RS stage iterations are made as the problem proceeds.

9. Newton’s method cannot continue, if for some Pn-1
a) f’(Pn+1)
b) f’(P)
c) f’(Pn-1)
d) P

Answer: c
Explanation: Newton’s method cannot continue if for some f’ (Pn-1), as the derivative at some point becomes zero then this is called as failure in the newton’s method.

10. Given ε>0. Then
a) f(a)f(b)>0
b) f(a)f(b)=0
c) f(a)f(b)=1
d) f(a)f(b)<0

Answer: d
Explanation: Choose a and b so that f (a) f(b)< 0, if a and b are not given they are assumed to be as the average value of f(0) for two consecutive negative and positive outcomes.