Maintenance; Regulations For Sulphuric Acid Additive (Max 50%) - ETATRON D.S. BT MA/AD Notice D'installation, Emploi Et Entretien

4.0 - MAINTENANCE

Fig. 10
5.0 – REGULATIONS FOR SULPHURIC ACID ADDITIVE (MAX 50%)
In this case it is necessary to take into account the following:
1. Substitute the flexible crystal PVC suction piping with semi-rigid polyethylene piping.
2. Remove all water present in the pump body (if water mixes with sulphuric acid a great amount of
gas is generated which will overheat the area and cause damage to the valves and pump
body).
To perform this operation when the equipment is not fixed to the plant, the pump can be pulsed for a few
seconds (15-30) keeping it overturned and without piping connected to the fittings. If this is not possible
disassemble and reassemble the pump body (Fig. 10), using the four fixing screws.
1. Periodically check the liquid level in the tank to make sure that the pump does not run
dry; even though no damage will occur to the equipment itself, this is recommended
to avoid any damages due to the lack of additive in the plant.
2. Check pump operation, screw seals and gaskets every 6 months and for very aggressive
liquids make more frequent checks and in particular monitor the concentration of the plant additive; a
reducti o n in additive concentration could be determined by wear on the valves (in this
case substitute the valves being careful to reassemble them as in Fig. 10) or by clogging
of the filter which must be cleaned as follows.
3. The manufacturer recommends periodical cleaning of the hydraulic parts (valves and filters). It is
no t p ossible to estab lish a clean in g freq uen cy a s this dep en ds on the type o f
ap plica tio n; the reagent to be used depends on the additive employed.
WARNING: to tighten the four screws use a
Dynamometer screwdriver set to a tightening
torque of 180÷200 Nxcm.
As stated above, we can suggest how to intervene if the pump is operating with sodium
hypochlorite (most frequent case):
a. Make sure the pump is electrically deactivated (both poles) by disconnecting the conductors
from the power supply using the omnipolar switch which must have a minimum
distance of 3 mm between its contacts.
b. Disconnect the plant outlet piping
c. Remove the suction piping (with filter) from the tank and place it in clean water
d. Start the dosing pump and leave it operating with water for about 5-10 minutes
e. With the pump disconnected, place the filter into a hydrochloric acid solution and wait until
the acid solution terminates its cleaning effect
f. Start the pump again making it operate with the hydrochloric acid solution for 5
minutes in a closed circuit situation, with the suction and outlet immersed in the same
container
g. Repeat the operation using water
h. Reconnect the dosing pump to the plant.
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