Comparison of Floor Model Manifold Freeze Dryers and Air Drying Methods
Soil microstructure testing requires dried samples. Traditional drying methods, such as air-drying and drying methods, have the defects of shrinking the volume of the soil sample, changing the microstructure state of the soil, and reducing the moisture content of the cohesive soil. Its microstructure will also change, reducing its volume. The conventional air-drying method and drying method easily change the microstructure of the soil, and cannot meet the test accuracy of microstructure research. The soil sample prepared by vacuum freeze-drying of the Floor Model Manifold Freeze Dryers ensures that the microstructure of the soil sample does not change after dehydration.
Comparison of Floor Model Manifold Freeze Dryers and drying and air drying methods:
The first method is air-drying. Due to the large surface tension of the liquid in the pores at normal temperature, it often causes the soil samples to shrink and crack, the soil particles rearrange, and the pore state changes.
The second method is the drying method. Due to the uneven distribution of molecular stress during the migration of water in soil samples, cracks and volume shrinkage occur. Physical and chemical interactions between soil particles can also occur at high temperatures.
The third method is lyophilization. The lyophilizer first makes the liquid water in the soil sample into non-crystalline ice at low temperature without volume expansion, and then allows the water to sublimate out of the vacuum pipe system under low temperature vacuum conditions to dry the soil sample.