Come and learn about ultrapure water quality
1. What does the resistivity and conductivity of ultrapure water represent?
What does the resistivity and conductivity of ultrapure water represent? In the water treatment industry, we often hear that conductivity and resistivity are used to represent the purity of water. What does this mean? How to test conductivity and resistivity? Today, Xiaobian will introduce the content and method of measuring the conductivity and resistivity of ultrapure water.
The resistivity of ultrapure water refers to the resistance between the two sides of a cube with a side length of 1cm at a certain temperature, and the unit is Ω·cm or MΩ·cm. Conductivity is the reciprocal of resistivity in S/cm (or μs/cm).
The resistivity (or conductivity) of ultrapure water reflects the salt content in the water and is an important indicator of water purity. The higher the purity of ultrapure water and the lower the salt content, the higher the resistivity of the water (the lower the conductivity).
The resistivity (or conductivity) of ultrapure water is affected by water purity, temperature, and various factors in the measurement. For the measurement of ultrapure water resistivity (or conductivity), a dynamic measurement method is selected, and the measured value is converted into a resistivity at 25°C by a temperature compensation method for easy measurement and comparison.
When measuring resistivity or conductivity, connect the conductivity electrode or measuring device to the water system. Evacuate the air bubbles in the pipeline measuring device and the conductivity cell with water, adjust the water flow (generally not less than 0.3m/s), install a thermometer at the outlet of the conductivity cell, and operate the conductivity meter according to the instrument manual (preheating, zero adjustment, calibration and measurement) , after the instrument reading is stable, record the water temperature and conductivity value. The online measurement uses a conductivity meter with thermometer compensation, which can directly read the conductivity value at 25 °C. The reciprocal of conductivity is the resistivity value.
2. How to ensure that the water quality of ultrapure water equipment meets the standard?
The quality of ultrapure water prepared by ultrapure water equipment depends to a certain extent on the equipment itself and the correct operation during daily use to maintain the quality of ultrapure water. So, how to ensure that the water quality of ultrapure water equipment meets the standard?
1. The storage tank of ultrapure water equipment should be equipped with an air filter to prevent air from entering the storage tank through the water inlet and causing water pollution.
2. Ultrapure water is easily polluted by environmental factors after taking water, and it should be used immediately when water is needed to minimize the contact between ultrapure water and the environment.
3. The water tank should not be placed in direct sunlight.
4. It should be avoided to store the ultrapure water in the storage bucket for a long time to prevent the water quality from being lowered due to long-term storage.
5. When the ultrapure water is used, the initial ultrapure water should be discharged first, and then the water should be taken from the water intake container.
6. When the ultrapure water equipment is not used for a long time, all the pure water in the pressure storage tank should be discharged to prevent pollution.
7. When the ultrapure water equipment is not in use for a short period of time, it needs to be turned on and watered once a week to prevent the growth of bacteria.
8. When taking water, try to avoid blisters that will affect the water quality.
The above is all about the quality of ultrapure water. Please look forward to more information about ultrapure water. Source: Rightleder