Abstract: Structurally hermetic light construction concrete which may be reinforced and comprising water, cement and light weight admixtures of inorganic, foamed or bloated or blown aggregates compatible with concrete and approximately spherical or elipsoidal in shape and in proportions corresponding to the sieve characteristic, wherein the grain densities and strengths of the light weight admixtures increase continuously or in more than two steps with increasing grain diameter, while the grain absorptions simultaneously decrease continuously or in more than two steps.

Abstract: A process for removing solids from a liquid wherein the liquid is passed through a bed of filter media comprising discrete, inorganic, artificially produced filter sand, and wherein the artificially produced filter sand has grain densities of between about 1.0 to 2.2 grams per cubic centimeter and grain diameters of between about 0.3 and 10 mm and the grain density decreases with increasing grain diameter.