Process and apparatus for cooling a gas containing SO
View Patent ↗The above mentioned invention describes a process for cooling a gas mixture of SO 2 and/or SO 3 and water, wherein the gas mixture is cooled by means of a first heat exchanger carrying a coolant. The temperature of the coolant lies above the dew point of the gas or gas mixture.
1. A process for cooling a gas mixture of SO 2 and/or SO 3 and water comprising cooling the gas mixture with a first heat exchanger carrying a coolant, wherein the temperature of the coolant lies above the dew point of the gas or gas mixture, the coolant is water, and the dew point τ given in ° C. is calculated according to the following equation:
τ
=
e
(
6.0006
-
(
3.158
·
10
-
7
p
·
1.244
·
10
-
9
·
c
)
)
+
(
0.1387
·
ln
(
p
·
1.244
·
10
-
9
·
c
)
)
with
p
=
gas
pressure
in
mbar
a
and
c
=
water
content
in
mg
/
Nm
3
.
2. The process according to claim 1 , wherein the water content is determined by a method based on a laser diode system.
3. The process according to claim 1 , wherein the gas mixture is cooled from a temperature between 400 and 500° C. to a temperature between 130 and 180° C.
4. The process according to claim 1 , wherein the coolant is heated so that the coolant at least partly evaporates.
5. The process according to claim 1 , wherein the gas mixture is guided through the first heat exchanger counterflow to the coolant.
6. The process according to claim 1 , wherein a second heat exchanger is provided before the first heat exchanger and that the coolant is guided first through the second heat exchanger and then through the first heat exchanger.
7. An apparatus for cooling a gas mixture of SO 2 and/or SO 3 and water comprising a first coolant-carrying heat exchanger with an inlet and an outlet for the coolant, a control or regulating device which adjusts the temperature of the coolant at the inlet to a temperature above the dew point of the gas or gas mixture, and a measuring device for determining the water content of the gas mixture, which is coupled with the control or regulating device such that the dew point τ given in ° C. is calculated according to the following equation:
τ
=
e
(
6.0006
-
(
3.158
·
10
-
7
p
·
1.244
·
10
-
9
·
c
)
)
+
(
0.1387
·
ln
(
p
·
1.244
·
10
-
9
·
c
)
)
with
p
=
gas
pressure
in
mbar
a
and
c
=
water
content
in
mg
/
Nm
3
.
8. The apparatus according to claim 7 , further comprising a second coolant-carrying heat exchanger with an inlet and an outlet, wherein a conduit connects the outlet of the second heat exchanger with the inlet of the first heat exchanger.
9. The apparatus according to claim 8 , wherein the first and/or the second heat exchanger includes cast ribs in its interior, by which the coolant is guided from the inlet to the outlet.
10. The apparatus according to claim 9 , wherein the first and the second heat exchanger are mounted in the same housing.
11. The apparatus according to claim 10 , wherein a three-way valve is provided, from which a feed conduit extends into the inlet of the first heat exchanger and into which extends a conduit from the outlet of the second heat exchanger and a conduit for supplying additional coolant, wherein the three-way valve is designed such that it adjusts the mixture of coolant from the second heat exchanger and additional coolant such that via the conduit coolant enters into the inlet of the first heat exchanger with a temperature above the gas or gas mixture.
12. The apparatus according to claim 9 , wherein a three-way valve is provided, from which a feed conduit extends into the inlet of the first heat exchanger and into which extends a conduit from the outlet of the second heat exchanger and a conduit for supplying additional coolant, wherein the three-way valve is designed such that it adjusts the mixture of coolant from the second heat exchanger and additional coolant such that via the conduit coolant enters into the inlet of the first heat exchanger with a temperature above the gas or gas mixture.
13. The apparatus according to claim 8 , wherein the first and the second heat exchanger are mounted in the same housing.
14. The apparatus according to claim 13 , wherein a three-way valve is provided, from which a feed conduit extends into the inlet of the first heat exchanger and into which extends a conduit from the outlet of the second heat exchanger and a conduit for supplying additional coolant, wherein the three-way valve is designed such that it adjusts the mixture of coolant from the second heat exchanger and additional coolant such that via the conduit coolant enters into the inlet of the first heat exchanger with a temperature above the gas or gas mixture.
15. The apparatus according to claim 8 , wherein a three-way valve is provided, from which a feed conduit extends into the inlet of the first heat exchanger and into which extends a conduit from the outlet of the second heat exchanger and a conduit for supplying additional coolant, wherein the three-way valve is designed such that it adjusts the mixture of coolant from the second heat exchanger and additional coolant such that via the conduit coolant enters into the inlet of the first heat exchanger with a temperature above the gas or gas mixture.