How to use turbidity analyzer and matters needing attention

What is a turbidity meter, how to use a turbidity analyzer, and what are the precautions when using a turbidity meter?

What is an online turbidity meter?

Turbidity, that is, the turbidity of the water, is caused by insoluble suspended solids and colloidal substances in the water. The measurement unit used in the ISO specification is FTU (turbidity unit), and FTU and NTU (turbidity measurement unit) are common. The turbidity meter measures the turbidity of water based on this principle.

How to use turbidity analyzer and matters needing attention:

1. Measure in time after sampling to prevent temperature changes and precipitation of water sample particles. The measurement results lack realism.

2. The sample bottle must be cleaned to avoid scratches and scratches. Clean the inside and outside of the sample bottle with laboratory cleaner, then repeatedly rinse with distilled water, and dry in a dust-free dry box. If you use it for a long time, soak it in dilute hydrochloric acid for 2 hours, and then rinse it with distilled water repeatedly. When sampling the bottle, only take the upper part of the bottle to prevent fingerprints from entering the light path.

3. Precisely prepare the calibration point of the standard solution, which is an important technique for turbidity measurement, to ensure the correct calculation, pay attention to the preparation of the standard solution at every step, shake the original solution evenly, pipette accurately, and pour it out to zero turbidity The meter should pay attention to the scale. The turbidity standard solution should use a large-volume measuring bottle to reduce preparation errors.u200b

4. Select the standard solution for calibration. The content should be selected from the entire scale of the measurement scale and should be shaken sufficiently before calibration. The calibration value should be correct before measurement. For low turbidity measurement and higher precision measurement, the measurement difference between bottles should be considered, and it is necessary to use the same bottle for calibration and testing. Schools should use zero turbidity water at zero hours, and distilled water can be used when the requirements are not high.

5. Representative water samples can accurately reflect the authenticity of water sources. Therefore, the water samples taken from each sampling point must be completely mixed before measurement to prevent the influence of water sample precipitation and larger particles. The air bubbles in the vial should be removed during preparation. When measuring a water sample with a lower temperature, condensed water droplets will appear in the bottle. Therefore, it is necessary to maintain a period of time before the measurement to make the temperature of the water sample close to room temperature and then scrub the watermarks on the bottle body.

6. When measuring, not only must consider the cleanliness of the sample bottle and the correctness of sampling, but also ensure the commonality of the measuring position. The graduation line of the bottle should be aligned with the positioning line of the sample holder, and it needs to be covered with a light shield to prevent stray light effects. When measuring the sample, the displayed value will change back and forth due to the drift of particulate matter in the water sample. At this moment, after a period of time, the value will gradually stabilize, and the turbidity value of the water sample can be read. The data may also be unstable due to excessive bubbles or suspended impurities in the water sample. When reading, take the center value, that is, the maximum display value plus the minimum display value, and divide by 2 to get the center value.