Heat & Mass Balance Report

8/6/2019 Heat & Mass Balance Report

1/12

Heat and Mass Balance Over Roaster Plant III

Mass Balance

Concentrate feed 39.75 t/hr

feed in kg/hr 39750 kg/hrMoisture content 10 %

Relative humidity 0.111

Dry feed 39749.89 kg/hr

Concentrate composition

Component % Kg/hr

Zn 52 20669.94

Fe 8.5 3378.74

Lead 1.5 596.25

copper 0.1 39.75

suphur 30 11924.97

C 0.9 357.749

Cd 0.16 63.60

SiO2 2 795.00

Insolubles 1 397.50


2/12

1. Reactions of zinc:Zn + S ZnS

65.4 32 97.4

20

669.

94

10113.73 30783.68

ZnS + 1.5 O2 ZnO + SO2

97.4 48 81.4 64

30783.68 15170.60 25726.81 20227.47

2. Reactions of lead:

Pb + S PbS

207.2 32 239.2

596.25 92.08 688.33

PbS + 1.5 O2 PbO + SO2

239.2 48 223.2 64

688.33 138.13 642.29 184.17

3. Reactions of copper:Cu + S CuS

63.5 32 95.5

39.75 20.03 59.78

CuS + 1.5 O2 CuO + SO2

95.50 48 79.5 6459.78 30.05 49.77 40.06

kg/hr

kg/hr

kg/hr

kg/hr

kg/hr

kg/hr


3/12

4. Reacti iFe + S FeS

Fe + S2 FeS2

Amount of Fe presentin FeS 75 % = 2534.06 kg

Amount of Fe presentin FeS2 25 % = 844.69 kg

Fe + S FeS

56 32 88

2534.06 3982.09

2 FeS + 3.5 O2 Fe2O3 + 2 SO2

176 112 160 128

3982.09 2534.06 3620.08 2896.06

Fe + S2 FeS2

56 64 120

844.69 965.35 1810.04

2 FeS2 + 5.5 O2 Fe2O3 + 4 SO2

240 176 160 256

1810.04 1327.36 1206.69 1930.71


4/12

5. Reacti of cadmi m:Cd + S CdS

112 32 144

63.60 18.17 81.77

CdS + O2 CdO + SO2

144.00 32 128 64

81.77 18.17 72.69 36.34

6. For Silica:SiO2 SiO2

795.00 795.00

7. For Carbon:C + O2 CO2

12 32 44


5/12

Feed and Product rate for different components:

Concentrate Feed rate Oxides Wt of oxides Oxygen req. SO2

(kg/hr) (kg/hr) (kg/hr) (kg/hr)

ZnS 30783.68 ZnO 25726.80882 15170.5998 20227.4664

PbS 688.33 PbO 642.2906757 138.13 184.17

FeS 3982.09 Fe2O3 3620.08 2534.06 2896.06

FeS2 1810.04 Fe2O3 1206.69 1327.36 1930.71

CuS 59.78 CuO 49.77 30.05 40.06

SiO2 795.00 SiO2 795.00 0 0

C 357.75 CO2 44.00 32 0

CdS 81.77 CdO 72.69 18.17 36.34

Insolubles 397.50 397.50 0.00 0.00

Total 38955.93 32510.82 19250.36 25314.81

Oxygen Required for 38.956 tonnes of concentrate = 19250.36 kg/hr

Oxygen Required for 1 tonnes of concentrate = 494.16 kg/hr

= 346.13 m3/hr

Oxygen Required for 39.75 tonnes of concentrate = 13758.49 m3/hr

Air Required for 39.75 tonnes of concentrate = 65516.60 m3/hr

Excess air = 25 %

= 16379.15 m3/hr

CO2 = 82.1846667 m3/hr

SO2 = 8865.72238 m3/hr

Clean Air escaping from top = 68137.26 m3/hr

Total Air at furnace inlet = 81895.75 m3/hr

Gases escaping from furnace top = 77085.17 m3/hr

calcine from top of the furnace = 75 %

= 24383.11 kg/hr


6/12

C l ine from bottom oft e furnace = 25 %

= 8127.70 kg/ r

Dust removing capacit of boiler = 45 %

Dust removing capacit ofC clone separator = 40 %

Dust removig Capacit of HGP = 15 %

intlet outlet underflow

Boiler 24.38 t/ r 13.41 t/ r 10.97 t/ r

C clone separator 13.41 t/ r 3.66 t/ r 9.75 t/ r

HGP 3.66 t/ r 0.01829 t/ r 3.64 t/ r

Heat Balance

Reactions involved :

Hf(KJ/mol

)

ZnS + 1.5 O2 ZnO + SO2

Ent alp

y

-204.6 0 -348 -296.84 KJ/mol -440.24

PbS + 1.5 O2 PbO + SO2

-98.12 0 -

218.08

-296.84 KJ/mol -416.8

CuS + 1.5 O2 CuO + SO2

-48.5 0 -155.2 -296.84 KJ/mol -403.54

2 FeS + 3.5 O2 Fe2O3 + 2 SO2

-201 0 -825.5 -593.68 KJ/mol -1218.18

2 FeS2 + 5.5 O2 Fe2O3 + 4 SO2-355 0 -825.5 -1187.36 KJ/mol -1657.86

CdS + O2 CdO + SO2

-208.4 0 -235.6 -296.84 KJ/mol -324.04

C + O2 CO2

0 0 -393.5 KJ/mol


7/12

Total Heat of Above reactions = - 4460.66 KJ/mol

Heat Balance for Furnace:

Temp.of calcine at furnace inlet = 25 CTemp.of calcine at furnace outlet = 920 C

t = 895 C

= 1168 K

Calcine flyover

m = 24383.11 kg/hr

Q = 21248538.45 kj/hr

= 21248.53845 MJ/hr

Air = 68137.26 m3/hr

m = 88158.32 kg/hr

Cp = 1 kj/kg-k

Q = 102968915.5 kj/hr

= 102968.9155 MJ/hr

SO2

m = 25314.81 kg/hr

Cp = 0.645 kj/kg-k

Q = 19071167.99 kj/hr

= 19071.16799 MJ/hr

Calcine uderflow

m = 8127.70 kg/hr

Cp = 0.75 kJ/kg-

kQ = 7082846.15 KJ/hr


8/12

= 7082.84615 MJ/hr

CO2

m = 44.00 Kg/hr

Cp = 1.22 KJ/Kg-

KQ = 62698.24 KJ/hr

= 62.69824 MJ/hr

Radiation Loss 3%

40699.3869 MJ/hr

water evap. Q=ml = 8581320 Kj/hr

= 8581.32 MJ/hr

Total heat output = 159015.486 MJ/hr

Heat Input = 4460.66 KJ/mol

Total moles = 350.29 kmol/hr

Q input = 1562537.85 MJ/hr

Qo/p = 159015.49 MJ/hr

Q left = 1403522.37 MJ/hr

For cooling coils

Q = m*L

latent heat of vaporisation, L = 2.42 MJ/Kg

m = Q/L

m = 17399.04 Kg/hr

= 17.40 t/hr


9/12

enthalpy of liquid water, h1 = 104.86 kJ/kg at 25 C

enthalpy of superheated steam,

h2

= 4398 kJ/kg at 920 C

h = 4293.14 kJ/kg

Q = mh

m = Q/h

= 9.80766316 t/hr

Heat Taken by cooling

coil

= 3%

Q = h*A*t h = 0.828 MJ/hr-m2-C

A = 54.98 m2 t = 925 C

Heat retained = 97%

Heat Balance Over Waste Heat Re-Boiler:

Temp.of calcine at boiler

outlet

= 350 C Calcine underflow temp. in

boiler

= 900 C

Temp.of calcine at boiler inlet = 920 C t =

=

20

t ==

570 C 293 K

843 K

Calcine flyoverM = 13410.71 Kg/hr

Q = 8434832.922 Kj/hr

= 8434.832922 Mj/hr

Air = 68137.26 m3/hr

m = 88158.32 kg/hr

Cp = 1 kj/kg-k

Q = 74317462.16 kj/hr

= 74317.46216 MJ/hr

SO2

m = 25314.81 kg/hr

Cp = 0.645 kj/kg-k

Q = 13764550.18 kj/hr

= 13764.55018 MJ/hr


10/12

Calcine uderflow

m = 10972.40 kg/hr

Cp = 0.75 kJ/kg-k

Q = 2398647.08 KJ/hr

= 2398.64708 MJ/hr

CO2

m = 44.00 Kg/hr

Cp = 1.22 KJ/Kg-K

Q = 45252.24 KJ/hr

= 45.25224 MJ/hr

Radiation Loss = 3%

= 0 MJ/hr

waterevap.

Q=ml

= 8581320 Kj/hr

= 8581.32 MJ/hr

Heat leaving

BoilerQ entering Boiler = 1513349.34 MJ/hr

Total Q leaving from top = 105143.418 MJ/hr

Heat leaving from boilerbottm

= 2398.64708 MJ/hr

Q1 retaining inside boiler = 1405807.27 MJ/hr


11/12

Heat Balance Over Cyclone Separator:

Temp.of calcine at Cyclone outlet 300 C

Temp.of calcine at Cyclone inlet 350 C

t 50 C

323 K

Calcine flyover

m 3657.47 kg/hr

Q 881414.1164 kj/hr

881.4141164 MJ/hr

SO2

m 25314.81 kg/hr

Cp 0.645

kj/kg-

kQ 5273961.696 kj/hr

5273.961696 MJ/hr

water evap. Q=ml

8581320 Kj/hr8581.32 MJ/hr

Radiation Loss 3%

0 MJ/hr

Heat Entering at cyclone inlet = 105143.418 MJ/hr

Heat leaving from Cyclone top = MJ/hr

Heat leaving at cyclone bottm = 2350.43764 MJ/hr

Heat Entering HGP = 102792.98 MJ/hr

Air =68137.26 m3/hr

m =88158.32 kg/hr

Cp =1 kj/kg-k

Q =28475136.75 kj/hr

28475.13675 MJ/hr

calcine uderflow

m 9753.25 kg/hr

Cp 0.75 kJ/kg-k

Q 2350437.64 KJ/hr

2350.43764 MJ/hr

CO2

m 44.00 Kg/hrCp 1.22 KJ/Kg-K

Q 17338.64 KJ/hr

17.33864 MJ/hr


12/12

Heat Balance Over Hot Gas Precipitator:

Temp.of calcine at HGP outlet 290 C

Temp.of calcine at HGP inlet 300 C

t 10 C

283 K

calcine flyover

m 18.29 kg/hr

Q 3861.303327 kj/hr

3.861303327 MJ/hr

SO2

m 25314.81 kg/hr

Cp 0.645 kj/kg-kQ 4620839.505 kj/hr

4620.839505 MJ/hr

CO2

m 44.00 Kg/hr

Cp 1.22 KJ/Kg-K

Q 15191.44 KJ/hr

15.19144 MJ/hr

Radiation Loss 3%

0 MJ/hr

Heat Entering HGP 102792.98 MJ/hr

Heat Leaving at HGP bottom 768.399362 MJ/hr

Heat retaining inside HGP 102024.581 MJ/hr

Air 68137.26 m3/hr

m 88158.32 kg/hr

Cp 1 kj/kg-k

Q 24948804.02 kj/hr

24948.80402 MJ/hr

calcine uderflow

m 3639.18 kg/hr

Cp 0.75 kJ/kg-kQ 768399.362 KJ/hr

768.399362 MJ/hr

water

evap.

Q=ml

8581320 Kj/hr

8581.32 MJ/hr

Documents

Heat & Mass Balance Report