The Series NXT3000 Gas Feed System is a family of vacuum-operated, solution-feed gas dispensing components including a vacuum regulator, meter assembly, and a selection of ejectors to meet customer needs for feeding chlorine, sulfur dioxide, ammonia or carbon dioxide gas. The Series NXT3000 is a versatile, high quality system which operates at sonic conditions eliminating the need for regulating differential pressure across the rate control valve. Proven design, rugged construction, and the use of the best available materials assures precise gas feeding, low maintenance and dependable operation for the life of the equipment. The vacuum regulator mounts directly on a 150 lb. cylinder, a ton container, or on the wall.
Several ejector choices are available for the Series NXT3000 system. The EJ100/200/500 ejectors can be used for general applications. These incorporate an O-ring and diaphragm type check valve. for more demanding applications – for on-off service, anti-siphon and high back pressure, up to 200 psig (1380 kPa), the EJ17 ejector can be used. In addition, a CHLOR-A-VAC® chemical induction unit can be used as the vacuum source for the system.
For applications requiring uninterrupted gas feed a builtin automatic changeover function is provided in every vacuum regulator. All that is required is two vacuum regulators. No separate changeover module or valve is required, but for complex vacuum changeover systems the Series NXT3000 vacuum regulators can be used with the CAPITAL CONTROLS® series of automatic vacuum switch-over modules.
Control Modes: The gas feeder can be controlled either manually or automatically by the use of a rate control valve. For a manual control application, a manual rate control valve is provided as part of the meter assembly. Where there are two meters in series in the same vacuum line, only one will have a rate control valve. There are numerous methods of automatic control. For all of these an automatic control valve consisting of a valve assembly (body, precision plug and valve seat) and an electric actuator is used. The actuator receives an electronic signal (typically from a flow meter or a residual controller) and positions the valve plug to permit an automatically regulated flow of gas to the process. An automatic control valve, complete with an integral controller, can be provided to directly receive the flow and residual analyzer signals. Please contact Advance Water Treatment representative for assistance with your control applications.
Standard metering tubes are available with the following maximum capacities: (20, 60, 200, 500 g/h, 1, 2, 4, 6 and 10 kg/h) of chlorine gas. Any combination of capacities may be used on multiple feed point applications as long as the total does not exceed (10 kg/h).
As for NXT3000 high capacity (20, 40 and 60 kg/h) are available.
