Many water treatment processes require the addition of small amounts of chemicals to the water. This chemical addition is effectively provided by small metering pumps. A measuring tank provides storage for the chemical to be added.
Chemical feed pumps are available in a variety of models, materials, and designs to
meet the specific needs of a process. The most common pump used to feed chemicals is a solenoid OR motor driven, diaphragm type, positive displacement metering pump.
Positive displacement metering pumps always provide the required volume of liquid
regardless of the discharge pressure. Compared to the performance curve of a centrifugal pump, the performance curve for a metering pump would be essentially a vertical line at a given flow, rather than a more or less horizontal curve.
In positive displacement pumps, the suction and discharge are usually created by a
solenoid pushing and pulling on a flexible diaphragm; in some cases, a cam on a motor shaft is used rather than a solenoid. The in and out movement of the diaphragm creates the forces of suction and discharge. This provides a pulse-type output. As the diaphragm pulls away from the pumping chamber, it creates suction on the inlet line; as it pushes back, it creates pressure on the discharge line. Check valves at the pump head inlet and outlet ensure that the liquid flows in the right direction. The result is a continuous sequence of small volumes of liquid being pushed out of the pump.
A chemical feed system consists of a measuring tank, metering pumps and ecessary valves and piping. Figure on the right shows a graphic of a system that includes all these components.
DEION Offerrs various capacities of Chemical dosing systems from 1 LPH capacity up to 1000 LPH depending on the system requirements.