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Warning: Ensure that the water tank temperature is 180˚F (82˚C). Liquid chlorine should
never be allowed into the vaporizer without the water tank temperature being in the
operating range.
i. Bring the vaporizer up to 50% and allow the system to reach equilibrium. Do the same at 75% of
scale and 100 % of scale.
3. System Start
This procedure may only be used after the initial start-up has been completed or if restarting the
system and the user is sure that no moisture has been allowed into the system and that no leaks are
present. If unsure, use the start-up procedure outlined in Section III.2.
Warning: When performing this step, ensure that all protective equipment for handling chlorine
gas is available.
a. Ensure that the chlorine container valves are closed and there is no chlorine in the piping. Turn on
the vaporizer, check to make sure that the water has filled up and the water tank temperature is at
operating level. Check that all appropriate alarms have turned off.
b. Connect piping to the chlorine gas container valves and allow chlorine gas into the system. Close
the gas container valves and check for leaks using a 26 Baume solution of ammonia. If white
smoke appears, a leak is present and corrective action must be taken.
c. Run the ejector(s) to remove chlorine from the pipeline. Close the isolation valves and connect the
manifold to the liquid chlorine container valves.
d. Close all valves in the manifold pipeline. Open the isolation valves, and slowly open the liquid
chlorine container valves and introduce liquid chlorine into the manifold piping.
e. Open the remaining valves one by one until they are all open.
f. Operate the vaporizer at 25% of full scale until equilibrium has been reached. Then bring up
to 50%, 75% and full scale making sure equilibrium has been established each time (when
temperature and pressure readings are constant over a set period of time).
Warning: Do not introduce liquid chlorine into the vaporizer without the water tank
temperature at operating conditions.
4. System Shut down
4.1 Short Term Shut Down
A short term shut down is defined as any situation where the chemical feed is only temporarily
interrupted, and the heater and all control functions will remain on. Hydro Instruments recommends
the following procedure:
a. If applicable, temporally stop chemical feed at the vacuum regulator and allow liquid to fill back
into the container.
b. Once an equilibrium has been reached (when temperature and pressure readings are constant over a
set period of time), shut the liquid & gas chlorine container valves. Keep all manifold valves open.
c. Run the ejector to remove all the chlorine out of the pipeline until the chlorine pressure reading
reads zero. Wait for 30 minutes to ensure pressure readings hold at 0 psi and then repeat this step
as necessary.
