摘要:
A process for the production of pourable, free-flowing granules which are suitable for use as wetting agents, detergents or cleaning products from aqueous solutions or suspensions of such materials in a fluidized-bed spray granulation apparatus employing a hot fluidizing gas. The aqueous selections or suspensions are dried with superheated steam as the fluidizing and drying gas wherein the drying step is carried out in a closed-loop system comprising a steam circuit from which the water evaporated from the aqueous solutions or suspensions of starting materials is removed as a partial stream and the thermal energy released is returned to the steam circuit. The granules are discharged from the granulation apparatus before they can be damaged by heat.
摘要:
The invention relates to an optimized process for conditioning a stream of superheated steam laden with steam-volatile organic components by condensation of the steam phase with recovery of the heat of condensation and at least partial separation of the steam-volatile organic components from the water-based condensate. The process operates with a first heat exchange stage in which the continuously introduced vapor stream is combined with a circulated and cooled liquid stream of condensed vapors. In a following second energy transfer stage, heat is indirectly removed from the liquid stream thus heated. A sidestream is removed from the liquid circuit of the condensed vapors and subjected to separation in a membrane process while the rest of the liquid stream is returned to the first stage. The invention also relates to the use of this working principle for industrial applications, more particularly for the separation of organic mixtures by superheated steam and/or the drying of water-based useful-material preparations with superheated steam as the drying gas.
摘要:
The invention relates to a solid material (primary drying product) containing alkali metal silicate with a modulus (molar ratio of SiO.sub.2 to M.sub.2 O, M=alkali metal) of 0.8 to 4 in homogeneous admixture with other inorganic and/or organic useful materials and/or auxiliaries, which has been dried from a finely sprayed aqueous preparation of mixtures of the alkali metal silicates and the inorganic and/or organic useful materials and/or auxiliaries by means of a hot gas stream. The solid material according to the invention is characterized in that, as a primary drying product in homogeneous admixture with the alkali metal silicate, it contains at least 10% by weight of water-soluble inorganic and/or organic salts, has apparent densities of at least 150 g/l, possesses a microporous absorbent internal structure and has been dried with superheated steam as the hot gas stream. The invention also relates in particular to detergent builder systems based on multicomponent systems containing this overdried alkali metal silicate and to their use for subsequent impregnation with other free-flowing useful materials and mixtures thereof from the field of detergents and to the detergents obtained.
摘要:
A process for drying water-containing materials in a closed-circuit system using a vertical drying tower having inlets located at a lower portion of the tower, the inlets circulating superheated steam in countercurrent to the water-containing materials descending through the vertical drying tower thereby drying the water-containing materials, the improvement being:(a) providing an auxiliary fluid having a temperature below that of the superheated steam entering into the vertical drying tower;(b) providing a double jacket having a permeable inner wall wherein the double jacket surrounds the lower portion of the vertical drying tower below the inlets; and(c) introducing the auxiliary fluid through the permeable inner wall of the double jacket and into the vertical drying tower in a tangential or radial direction relative to the permeable inner wall.
摘要:
A process for the production of pourable and free flowing granules of materials or mixtures thereof which are suitable for use as wetting agents, detergents or cleaning products wherein an aqueous solution or suspension of the wetting agents, detergents or cleaning products is dried using a hot gas stream of superheated steam. Drying is terminated before the granules are damaged by heat, and the hot gas stream is freed from entrained particles of the materials by means of filters.
摘要:
A process for granulating a polyamide resin involving: (a) providing an underwater granulating device having a heated multiple-bore die wherein the bores have an internal diameter ranging from 1.2 to 2.5 mm and a length of from 12 to 50 mm; (b) providing a polyamide resin melt having a viscosity, at 160° C., of less than 3,000 mPas; (c) cooling the polyamide resin melt to form a cooled polyamide resin; (d) introducing the cooled polyamide resin into and through the heated multiple-bore die to form an extrudate; (e) providing a source of water; (f) contacting the extrudate with the water to form a cooled extrudate; and (g) cutting the cooled extrudate into granules.