Clayton Steam Generator model EO-100-1
PAGE 51 / 70
Instruction Manual, doc.nr.: MAN18206 Rev A PSC
•
Continue circulation 4 to 6 hours. A longer circulation will be required if bubbling still occurs in the
discharge solution.
•
Test acid at regular intervals by dropping in a pinch of ordinary baking soda. If no foaming reaction
takes place, the acid has been neutralized and it will be necessary to add more acid to the solution. If
baking soda is not available use pH indicator paper. PH reading should be 6.5 to 6.8
•
Shut down plant. Carefully remove suction and discharge hose from acid container and direct them
into a drain. Open separator drain valve
[32].
Allow as much of the solution to drain to waste as
possible; then remove suction hose and install water pump intake hose.
•
Fill hotwell. With discharge hose still directed to drain, start plant without burner operation and allow
to run for about 30 minutes to purge system of acid solution. Be sure feedwater pump remains primed.
Flush pump column by opening drain cock at base of pump until clear water appears.
•
Stop plant and remove discharge hose. Inspect and clean waterpump check valves, close seperator
drain valve
[32].
9.2.2
REMOVAL OF EXCESSIVE SOOT FROM HEATING COIL
-An authorized Clayton technician should supervise this operation
Where the steam generator has been operated with improper air adjustment for any period of time of where
uniform periodical soot blowing has not been followed, it may be necessary to wash the coil with water to
remove the excessive soot accumulation.
•
Set
[S01]
in position 2
( pump )
and let the generator running for about 15 minutes to cool the unit
before the washing is started.
•
Disconnect and remove stack section immediately above the heater cover.
•
Remove the burner manifold.
•
Provide a trough under the burner volute opening to drain off the water used for washing the coil.
CAUTION :
Wear protective clothing !!! At first, add the acid at a very slow rate until
circulation can be maintained without excessive bubbling from the discharge hose. For
example, add about 200 cm3 and wait for reaction to subside; then add another 200 cm3 etc....
As the cleaning operation progresses, acid can be added in gradually increasing amounts. In
extreme cases, it is possible to completely block the passage through the coil with loosened
scale if acid is added too rapidly. Adding the acid too rapidly will also cause bubbling in the
waterpump check valve housings and result in loss of pump prime
WARNING :
Some countries
(or local rules)
do not allow that the water is drained to the
sewer. Please verify if special rules are applicable for your country or region. If so, consult a
specialized company for neutralisation and removal of the water
IMPORTANT :
Start plant and blowdown the unit thoroughly 4 or 5 times before
resuming normal operation
NOTE :
During this period, frequently check to be sure feedwater pump is primed.
The only way to make sure that the pump is primed is to slowly throttle coil feed valve
[26]
until pressure rises on feed pressure gauge. If pressure fails to rise, the pump must be
primed. Reopen coil feed valve
[26]
after check
