SY/T 5796-2020 in English

Interpretation of the core content of the standard

Key technical points

4.1 Agitator specification

The standard clearly requires that the blades should be made of lightweight and corrosion-resistant materials, with a size of 60mm×20mm, a speed range of 0-140r/min, and the agitator shaft should be 6mm away from the center of the beaker to ensure uniform shear force distribution.

6.1.2 Dosing procedure

The speed is controlled in three stages: 120-140r/min pre-stirring for 30 seconds → maintaining 1min after rapid dosing → reducing the speed to 60r/min for 10min, simulating the gradient mixing process of on-site working conditions.

Implementation and application suggestions

1. Water sample collection: A dry and insulated sampling bucket must be used to take ≥3L of raw water without flocculant. The valve must be flushed for 3-5 minutes before sampling. The experiment must be completed within 12 hours
2. Oil content detection: Strictly follow the SY/T 0530 standard, and avoid disturbance when transferring 150mL of the upper clear liquid
3. Equipment calibration: The wavelength accuracy (380-720nm) of the spectrophotometer must be calibrated regularly, and the electronic balance must maintain a sensitivity of 0.1mg

Analysis of standard evolution

The 2020 version deletes non-essential content such as the test tube rack structure diagram and evaluation report form in the 1993 version, and strengthens the scientific nature of the methodology:

• Added requirements for reagents such as n-hexane and nitrogen
• Introduced modern testing equipment such as microporous membrane filtration tester
• Specified that after standing for 30 minutes, the floating floc layer must be completely removed before sampling