View

Q57

FAILNATpage 33holdREVIEW_LOW_CONFIDENCEP2UNREVIEWED

type=NAT · page=33–34 · marks=2 · content_conf=0.7999999999999999 · math_conf=0.778

Original PDF33

Loading original page…

file: GATE CH 2020 (with Solutions).pdf

pages: 33–34

No clips linked

An aqueous suspension at

60^0 C

is fed to the first effect of a double effect forward feed evaporator with a mass flow rate of 1.25 kgs

⁻¹.

The sum of the rates of water evaporated from the first and second effects is 1.0 kgs

⁻¹.

Temperatures of the exit streams from the first and the second effects are

100^0 C

and

60 ⁰ C,

respectively. Consider the specific heat of the aqueous suspension, and the latent heat of phase change for water to be 4 kJ kg

⁻¹ K^{ - 1}

and 2200 kJ kg

⁻¹,

respectively, over this temperature range. The steam economy (in kg per kg) is____(round off to 2 decimal places).

none

1.7774

V_1 = xV_2 = 1-x

m/\& = /frac{1.25kg}{s}

.

SteadF/m/S

L_1L^2

T_F = 60^0C,T₁=100⁰ C,T₂=60⁰ C

.

.

F = L_1+V_1

1.25 = L_1+x ⇒ L_1 = /frac{(1.25-x)kg}{s}

Energy balance on I^sᵗ stage

FC_p(T_1-T_F)+V_1/lambda{}_v = S/lambda{}_s

1.25(4 /times 10^3)(100-60)+x(2200 /times 10^3) = S(2200 /times 10^3)

200000+2200000x = 2200000S

11x-11S+1 = 0

11x = −1+11S…(i)

Energy balance on II stage

L_1CP(T_2-T_1)+V_2/lambda{}_v = V_1/lambda{}_s

(1.25-x)(4)(60-100)+(1-x)(2200) = x(2200)

4240x =2000

x = /frac{0.4716kg}{s}

On substituting this value in equation (i)

11(0.4716) = −1+11S

S = 0.5626kgs

.

Economy of =1.7774

Category: REVIEW_LOW_CONFIDENCE · Priority: P2 · Disposition: extraction_defect

Extractor validation_status=low_confidence.

Suggested action: compare_pdf_and_extracted

state=UNREVIEWED · resolution=— · trust=UNRESOLVED · WAVE-12 priority=P2

Review actions

Writes a viewer overlay only. Never converts verification REVIEW into automatic PASS.

ActionFieldReason

No overlay recorded yet.

Source PDF: GATE CH 2020 (with Solutions).pdf

Segment	Page	BBox	Asset	Equation	Link
stem	33	`—`	`—`none	`—`	`REVIEW`
stem	33	`—`	`—`none	`—`	`REVIEW`
stem	33	`—`	`—`none	`—`	`REVIEW`
stem	33	`—`	`—`none	`—`	`REVIEW`
stem	33	`—`	`—`none	`—`	`REVIEW`
stem	33	`—`	`—`none	`—`	`REVIEW`
stem	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`
solution	33	`—`	`—`none	`—`	`REVIEW`

Equations:none