Advantages and disadvantages of particle size test methods

1) Sieving.

Advantages: simple, intuitive, low cost equipment, commonly used in the sample what size is greater than 40um.

Disadvantages: Results greatly effected by human factors and mesh deformation.

2) Microscope (picture) method.

Advantages: simple, intuitive and morphology analysis. Apply to narrow size distribution samples(Ratio of the maximum and minimum particle size is less than 10: 1)

Disadvantages: low representation,not apply to wide size distribution of samples, and can not analyze a sample size which is less than 1um.

3) Sedimentation

(including gravity sedimentation and Centrifugal sedimentation).

Advantage: Operation gradient, the instrument can operate continuously, low price, good accuracy and reproducibility, wide test size range.

Disadvantages: long test time, complicated operations.

4) Resistance

Advantages: simple operation, the equivalent concept clear, fast , good accuracy. Disadvantages: not suitable for measuring the sample is less than 0.1um particles, It's hard to replace orifice tube for wide particle size range of sample.

5) laser scattering method.

Advantages: easy to operate, fast test speed, wide test range, good repeatability and accuracy, on-line measurement and dry measurement.

Disadvantages: Results influenced by the distribution model, high equipment cost, low resolution.

6) electron microscopy.

Advantages: suitable for testing new super-particles or nanoparticles, high resolution, can morphology and structural analysis

Disadvantages: less sample, low representative, easily effected by human factor ,instruments are expensive.

7) Photo-resist method.

Advantages: fast and convenient test, can measure the number of particles in a liquid or gas, and high resolution.

Disadvantages: Not applicable to sample size of less than 1um, only suitable for dust, pollutants or diluted drugs.

8) Ventilation method.

Advantage: Low price instrument. No need to disperse samples,The samples were not dispersed, can test plastic powder.

Disadvantage: Only test average particle size value ,can not be measured particle size distribution; can't measured fine powder price size less than 5um.

9) X-ray small angle scattering method, measure particle size of nanoparticles.

10) photon correlation spectroscopy (dynamic light scattering method). Measure particle size of nanoparticles.