Abstract: A system and an associated process are described for the determination of grain size distribution of particles in suspension. The suspension is settled in a settling tank and optical density measurements of the suspension are taken and from this the grain size distribution is determined. According to the invention, the suspension is homogenized by circulating it in the settling tank, then circulating is stopped and the optical density is repeatedly measured in the settling tank on at least three points with deviating spacings. The equipment described is a settling tank (1) for the suspension, a device for the measurement of optical density in the settling tank (1) and a computing unit calculating the grain size distribution from the optical density values measured. The settling tank (1) is equipped with a means for the circulation of the suspension and there are at least three measuring heads (2,3,4,5,6) along the settling tank (1) sensing the optical density.

Abstract: A process for the production of chemically bonded non-woven material, such as synthetic leather, is disclosed wherein a fiber fleece is impregnated with a heat sensitized polymer dispersion and the composition is destabilized to form a porous gel structure. Finally, the polymer is crosslinked at below 150.degree. C. and is dehydrated. Additionally, cut fibers of polyester of polyamide are formed into a fleece and an aqueous dispersion of butadiene-styrene coagulant and a curing composition is impregnated through the fleece. The binder is gelled and cured in superheated steam. The products obtained are soft and possess excellent physical and mechanical properties as well as superior dynamic stressability.

Abstract: Subject of the invention is drying equipment suitable for reducing the moisture content of fragmentary materials, mainly clay. The drying equipment contains drying space developed as a ring of circular, or polygonal base, surrounded with latticed surfaces. The drying space includes a channel developed as a ring of circular, or polygonal base, surrounded with latticed surface, carrying drying medium. The device, feeding the material to be dried is connectible to and turnable around the central shaft. Conveyance of the material takes place with the aid of a rotary worm or scraper device fixed to the central shaft.