The total solid content in the water is to evaporate the water sample and continue to dry to a constant weight, and the final residue obtained is the total solid. For dissolved solids, the water sample is filtered first and then dried to constant weight at a specified temperature. In addition, this kind of method is suitable for water samples with dissolved solids not less than 25mg/L.
Instruments used for the detection of dissolved solids in water
1. Drying box.2. Analyze the balance.
3. Slow quantitative filter paper or glass sand core funnel with filter plate pore size of 2-5um.
4. The diameter of the evaporating dish is 100mm.
5. Dryer.
6. Constant temperature water bath.
Operation steps for dissolved solids in water
Filter the water sample to be tested with a slow quantitative filter paper or a glass sand core funnel with a filter plate pore size of 2-5um. Use a pipette to transfer 100 mL of the filtered water sample and place it in an evaporating dish that has been dried at 105-110°C to a constant weight. Place the evaporating dish on a boiling water bath to evaporate to dryness, and then dry the evaporating dish at 105-110°C to a constant weight. Finally, the content of soluble solids in the water sample is calculated using the relevant formula.
Inspection notes
1. In order to prevent debris from falling into the drying process and affecting the test results, a glass tripod must be placed on the evaporating dish and covered with a watch glass.2. When evaporating the water sample to dryness, do not put the evaporating dish directly on the electric heating plate or electric stove to directly heat it, otherwise the splash of water droplets will cause loss when the water sample is boiling, and the measurement result will be low. Asbestos netting can be added or the electric heater can be adjusted smaller.
3. Porcelain evaporating dish used for measuring dissolved solids, glass evaporating dish can also be used instead of porcelain evaporating dish. The advantage is Yi Hengzhong.
4. The water surface of the water bath should not be in contact with the evaporating dish, so as not to contaminate the evaporating dish and affect the measurement results.
This is how to detect dissolved solids in water
