Wet Sieving

What is wet sieveing?

Wet sieving is a procedure used to evaluate the particle size distribution or gradation of granular materials. It is mainly used to deal with materials that are easy to agglomerate, sticky or contain moisture. Unlike dry sieving, wet sieving assists sieving by adding liquid (usually water) to make the material pass through the screen more easily, thereby improving sieving efficiency and accuracy.

Video of wet sieving

How does the wet sieving work?

Wet sieving uses the aperture size of the screen to separate materials of different particle sizes. However, wet sieving disperses the materials in the liquid by adding liquid, thereby:

1、Reducing the agglomeration between particles: Liquid can effectively disperse fine particles and prevent them from agglomerating due to static electricity, van der Waals forces, etc., thereby improving sieving efficiency.

2、Removing adhesive impurities: Liquid can wash away impurities adhering to the surface of particles and improve sieving accuracy.

3、Suitable for fine particle sieving: For very fine particles, dry sieving is prone to clogging, while wet sieving can effectively solve this problem.

When should wet sieveing be used?

Wet sieving can be used to remove fine particles that are difficult to separate by dry sieving before routine drying and sample testing. Wet sieving is particularly suitable for solid materials that are insoluble in water and unaffected by water (for example, solids that swell when exposed to water are not suitable) and remain stable when heated to 110°C.

Materials and applications

Wet sieving is an ideal pre-treatment method when dealing with samples that contain a lot of particulate matter and fines that are sufficient to prevent sieving. This is because fines tend to clump together, causing inaccurate sieving results. Wet sieving is also suitable for direct measurement of particle size in certain specific materials, including:

1、Soils and mineral aggregates rich in fine particles

2、Fragile but water-insoluble materials such as coal or other minerals

3、Light powders

4、Sludge and glazes

5、Kaolin and fillers

6、Abrasives

7、Micronized materials

What is dry vs wet sieving?

What is wet sieveing uesd for?

1.Construction: Wet sieveing is often used to determine the fineness of cement and other raw materials.

2.Aggregate Processing: Used to clean rock and other aggregates to remove clay and silt and ensure accurate particle size measurements.

3.Laboratory Analysis: Wet sieveing is also used in laboratory analysis of fine powders and materials that are difficult to dry screen.

How do testing procedures work?

Wet sieving usually has two purposes: one is to determine the amount of material remaining on a specific sieve, and the other is as a sample pretreatment step to facilitate easier or more accurate particle size analysis. In simple terms, wet sieving can be used to directly measure how many particles of different sizes there are; wet sieving can also be used to pre-treat samples to make subsequent particle size analysis more accurate; which wet sieving method you choose depends on what results you ultimately want to achieve.

Wet sieveing Information Summary

Wet sieving precautions

1、Initial weight: Before you begin wet sieving, be sure to record the total weight of the dry sample, as this data will be used in subsequent calculations.

2、Soaking: If time permits, it is best to soak the sample for a period of time first. This helps soften lumps and makes the wet sieving process smoother.

3、Spraying water: During sieving or stirring, use a nozzle or sprayer to evenly spray water on the sample to ensure that the sample is fully wetted.

4、Water pressure: Control the water pressure and use a gentle, steady stream of water to avoid washing away the sample.

5、Sample loss: A small amount of sample may be lost during wet sieving, such as being washed away during stirring or decanting, or getting stuck in the gaps of the sieve.

6、Trade-offs: Despite the small amount of loss, wet sieving is generally more accurate and efficient than dry sieving, especially when dealing with certain special samples.

Wet Sieving Equipment

Wet Wash Screens: These screens have a deep screen frame to prevent overflow and have drainage holes to handle wash water. Some models also come with replaceable screen assemblies for convenience.

Stainless Steel Options: Stainless steel screens are durable and corrosion-resistant, suitable for repeated use in the wet sieveing process.

Accessories: Aggregate washers and other accessories are available to automate the washing process, increasing efficiency and consistency.

Wet Sieving is a method of sieveing with the aid of liquids, which is particularly suitable for materials that are prone to agglomeration, sticky or contain water. Although wet sieveing equipment is expensive and the subsequent processing is complicated, its efficient sieveing effect and wide applicability make it widely used in the fields of food, chemical industry, mining, etc.