droogzeven

Droogzeven, or dry sieving, is a method to separate particulate material by size using a sequence of sieves with decreasing openings, performed while the material remains dry. It is commonly used to determine particle size distribution and to prepare fractions for further testing or processing.

During the procedure, a representative sample is placed on the top sieve of a stack and subjected to agitation or vibration for a defined period. After sieving, the mass of material retained on each sieve and the mass that passes the bottom pan are recorded. The data are expressed as percent retained on each sieve or percent passing, forming a particle size distribution curve.

Equipment consists of a sieve stack, a frame, and a shaker or manual shaking; sieves are categorized by their mesh sizes and materials. Dry sieving requires the material to be dry; moisture or cohesive powders may clump and skew results, in which case drying or alternative methods may be used.

Applications span geotechnical engineering, construction materials, mining, mineral processing, and food analytics, among others. The method is often contrasted with wet sieving, where the material is analyzed in a liquid medium to facilitate separation of fine particles or to reduce dust.

Standards and laboratory practices: In many countries, standardized sieve analysis procedures exist for soils, aggregates, and powders, enabling comparability of results across laboratories.