Evoqua V10K, Manual

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WT.025.100.001.UA.IM.0614
V10K V-NOTCH CHLORINATOR
34
EVOQUA W3T109612
3.1 Description
3.1.1 Intended Use
The V10k Gas Feeder is the central item of a disinfection system which doses
gas under vacuum into a flow of water at rates ranging up to 750 ppd (15 kg/h).
Other use is prohibited without permission from Evoqua Water Technologies.
3.1.2 Theory of Operation
The Evoqua Water Technologies V10k Gas Feeder is designed to control and
indicate the rate of flow of gas under vacuum. It provides a simple means of
setting the feed rate at any value within the range of the machine and mixes
the gas with water.
Operating water passes through an injector to produce a vacuum which draws
gas from the gas feeder. This gas mixes with the water flowing through the
injector. A poppet check and diaphragm check are built into the fixed throat
injector to prevent a backflow of water into the gas feeder should the injector
water supply be shut off with pressure on the injector discharge, or should
the injector discharge line be restricted. Proper operation of the injector is
dependent on the inlet pressure being sufficiently higher than the discharge
pressure. The differential regulating valve in the V10k control unit throttles the
injector vacuum to maintain the proper operating vacuum on the downstream
side of the V-notch variable orifice relative to the gas supply vacuum.
Gas under pressure enters the vacuum regulator. The gas pressure is reduced
to less than atmospheric pressure as the gas passes through a valve seat which
will not open unless an operating vacuum is produced by the injector. This
provides a controlled vacuum on the upstream side of the V-notch variable
orifice. In the extremely unlikely event that the valve passes gas under pres-
sure, a pressure relief valve permits this gas to pass out the vent.
From the vacuum regulator, gas under a controlled vacuum passes through the
rotameter (feed rate indicator) causing the float to indicate the rate of flow on
an easily read scale. The rate of flow is controlled by the position of the V-notch
variable orifice across which a constant differential at less than atmospheric
pressure is maintained, by the combined operation of the differential regulat-
ing valve and the vacuum regulator.
In the event of gas supply exhaustion, the diaphragm check valve in the injector
will close when the system reaches full vacuum.
If the operating water is shut off, the vacuum breaks down and the vacuum
regulating valve interrupts the gas flow. In case of a leak in the tubing from the
vacuum regulating valve to the injector or in the gas feeder, only air can enter
into the system, but no gas can escape.