The Cologne Cathedral is a venerable old building whose historic substance is preserved by continuing restoration works. Mortar is one of the construction materials that the conservators use for preservation and restoration of the ancient stones. To obtain mortar with optimum quality, the conservators at the cathedral workshop in Cologne use a RETSCH sieve shaker to determine the particle size distribution of the material.
The determination of the particle size distribution of a product has always been of great significance in food production. Taste, color, solubility or extraction behavior are only a few examples of product properties which are directly influenced by particle size. Traditionally, analytical test sieving provides a quick and simple possibility to characterize the particle size of bulk goods. In the testing laboratory of the St. Petersburg branch of LLC Wrigley RETSCH sieve shakers AS 200 jet and AS 200 control are utilized for particle size analysis of fine powders which are used for chewing gum production.
Re-using raw materials is an important factor in powder metallurgical
processes. RETSCH offers a range of instruments which are suitable for
sieving powders and pulverizing metal parts both of which are
re-introduced into the production process.
The determination and knowledge of the particle size distribution is an essential part of the quality control process for industrial products. From incoming and production control to research and development sieve analyses are used to determine a number of parameters or simply the particle size. Easy handling, low investment cost and high accuracy make sieve analysis one of the most frequently used procedures for measuring the particle size. This white paper gives an overview of the different sieving techniques and describes the necessary steps to ensure reliable results.
Graduate student Jennifer Franz has developed a new inspection procedure during her work at the German food producer Lebensgarten GmbH. With the help of sieve analysis the company can
now reliably ascertain the fines and dust fractions of incoming cereal flakes; these have a negative influence on the mixing and packaging process of muesli.
Sample preparation of vegetable-based raw materials with laboratory mills
Thanks to the increasing usage of biomass as a source of energy, the analysis of these materials in the context of R&D and quality control gains importance, too. Due to the complex properties of plant materials, adequate sample preparation can be rather a challenge.
Use of laboratory grinders for size reduction of human bones and bioceramics
Bone implants and substances for bone regeneration are used in surgery to replace degenerated bone material by implants or to “re-build” it with specific substances. The material used in implants varies from autogeneic (supplied by the patient) through allogeneic (supplied by a donor) bones to replacement materials such as hydroxylapatite (HA) and tricalcium phosphate (TCP). Bovine bones and corals are used in conjunction with synthetically produced foamed materials to form a basis for the regeneration of bone substance. Various RETSCH mills are suitable for the preliminary and fine grinding of human bones as well as bioceramic materials.
Many natural and manufactured materials occur in a disperse form, which means that they consist of differently shaped and sized particles. The particle size distribution, i.e. the number of particles of different sizes, is responsible for important physical and chemical properties.