Industrial Ultrapure Water Production Dosing and Metering Equipment

Lifting Equipment

Lifting equipment is required for transferring chemicals from the mixing tank/storage tank to the solution tank, and also when the solution tank height is insufficient for gravity-based dosing. Commonly used equipment includes corrosion-resistant pumps and water jet injectors.

Common corrosion-resistant pumps include corrosion-resistant metal centrifugal pumps, plastic centrifugal pumps, and corrosion-resistant submersible vertical pumps. Additionally, there are corrosion-resistant ceramic pumps and fiberglass pumps.

Although water jet injectors are less efficient, they are convenient to use, simple to operate, and reliable, and were once widely used in chemical dosing systems. However, due to the increase in the variety and quality of corrosion-resistant pumps, the use of water jet injectors in large and medium-sized water plants has been decreasing.

Dosing Metering Equipment

Common dosing metering equipment includes metering pumps, circular flow meters, orifice injectors, and float cups. Metering pumps are widely used due to their high metering accuracy and ability to automatically adjust dosing.

1. Orifice Metering: Orifice metering utilizes the stable flow rate of free outflow from an orifice at a constant immersion depth for measurement. The flow rate can be adjusted by changing the orifice area.

2. Float Cup Metering: Float cup metering devices utilize a float at a fixed immersion depth h or liquid level difference in the solution to achieve a constant outflow. Suitable for situations where the solution tank changes liquid level, it is a small metering device. However, at low temperatures, phenomena such as flattening or floating of the outlet pipe can occur, affecting the accuracy of the dosage.

3. Rotameter Dosing Device: A rotameter consists of a rotor inside a conical glass metering tube. When gas or liquid flows through the conical metering tube, it pushes the rotor up and down to achieve the metering purpose. A rotameter dosing device is a solution dosing device composed of a rotameter as the metering element, combined with control valves, water ejectors, clarifiers, or filters. Standard products of this type are already available.

4. Dosing Pumps: The most commonly used dosing pump is the diaphragm pump, which adjusts the dosing volume by changing the motor speed (i.e., changing the stroke frequency) or the stroke length. The adjustment method can be rationally determined during design and production according to the process requirements of water purification and chemical dosing in the water plant.

The dosing pump system can have different configurations depending on the chemicals used and the type of pump, but for the sake of ensuring accurate metering and safe operation, the basic configuration is largely the same. Metering equipment plays a crucial role in the ultrapure water extraction process.