Process for manufacturing effervescent granules and tablets and high efficiency granulation tower for such process

Abstract

The invention relates to a process for manufacturing effervescent tablets consisting in the steps of careful humidifying of the acid+base mixture, pre-drying and final drying and granulating. It has been found that these operations can be performed in a single apparatus, either integrally in fluid bed, or with vacuum-drying.

What is claimed is: .[.1. A process for the manufacture of effervescent tablets in which the powdered raw materials therefor are mixed and the mixture is carefully humidified by a solvent followed by granulation and drying, wherein the steps of mixing said raw materials, humidifying the mixture with the solvent and drying are conducted inside the same apparatus, wherein the drying step is performed in vacuo..]. .[.2. The process of claim 1, wherein the components of the mixture are: 
     
       citric acid..]. .Iadd.10.  A process for the manufacture of effervescent tablets from a plurality of powdered raw materials, with the avoidance of external contamination, said process comprising the steps of: (a) storing said powdered raw materials in storage hoppers;   (b) transferring said raw materials downwardly by gravity to a granulator-vacuum-dryer device, introducing into said granulator-vacuum dryer device a granulation agent in an amount effective to wet form wet granules and drying under vacuum said wet granules therein to obtain dried granules;   (c) evacuating the dried granules by gravity from said granulator-vacuum dryer, transferring them downwardly by gravity to a cooler and cooling said dried granules to a temperature at which destabilization is impeded; and   (d) transferring said dried and cooled granules downwardly by gravity to a storage container;   said process being carried out in an enclosed vertically arranged apparatus   
     
     
        array. .Iaddend. .Iadd.11.  The process of claim 10, wherein the raw materials are individually subjected to said steps (a), (b) and (c), then mixed together and subjected to direct compression. .Iaddend. .Iadd.12. The process of claim 10, wherein the raw materials are pre-mixed within said granulator-vacuum-dryer device. .Iaddend. .Iadd.13. The process of claim 10, wherein said granulation agent is a solvent selected from the group consisting of demineralized water an aqueous wetting solutions. .Iaddend. .Iadd.14. The process of claim 10, wherein said granulation agent is a solution of dioctylsulfosuccinate in water. .Iaddend. 
     
     
        .Iadd.     The process of claim 10, wherein after drying and cooling, the dried and cooled raw materials are transferred by gravity to a calibration device. .Iaddend. .Iadd.16. The process of claim 15, wherein after calibration, said dried, cooled and calibrated raw materials are transferred by gravity to a band mixer. .Iaddend. .Iadd.17. The process according to claim 10, wherein the raw materials are weighed before any treatment. .Iaddend. .Iadd.18. The process of claim 10, wherein said dryer has a jacket for a heat exchange fluid and during said drying step (b), said raw materials are subjected to mechanical stirring with lump-breaking cutters, a vacuum is created and a granulation agent introduced by aspiration, the temperature being regulated by circulating a heat-exchange fluid in said jacket. .Iaddend. .Iadd.19. The process of claim 10, wherein the raw materials comprise: effervescent mixture: sodium bicarbonate   citric acid and the granulation agent is demineralized water. .Iaddend. .Iadd.20. The process of claim 19, wherein the effervescent mixture contains glycocoll. .Iaddend. .Iadd.21. The process of claim 10, wherein the raw materials comprise:       paracetamol   monosodium carbonate   monopotassium carbonate   sorbitol   anhydrous citric acid   ascorbic acid and the granulation agent is a solution of sodium dioctylsulfosuccinate in     
     
     
        water. .Iaddend. .Iadd.22.  The process of claim 10, wherein the raw materials in powder form are as follows: calcium carbasalate   1ysine carbamate   citric acid .Iaddend. .Iadd.23. The process of claim 10, wherein the raw materials are as follows:   calcium carbasalate   1ysine carbamate   citric acid   aroma   PEG (polyethyleneglycol)   
     
     
       ammonium saccharinate. .Iaddend. .Iadd.24.  A process for the manufacture of effervescent tablets from a plurality of powered raw materials, with the avoidance of external contamination, said process comprising the steps of: (a) storing said powdered raw materials in storage hoppers;   (b) transferring said raw materials downwardly by gravity to a mixer-granulator-dryer device, mixing said raw materials, introducing into said mixer-granulator-dryer device a granulation agent, mixing the raw materials and the granulation agent under substantially atmospheric pressure for a period of time sufficient to achieve formation of wet granules and drying under vacuum said wet granules in said mixer-granulator-dryer device to obtain dried granules;   (c) evacuating the dried granules by gravity from said granulator-vacuum dryer, transferring them downwardly by gravity to a cooler and cooling said dried granules to a temperature at which destabilization is impeded; and   (d) transferring said dried and cooled granules downwardly by gravity to a storage container;   said process being carried out in an enclosed vertically arranged apparatus   
     
     
        array. .Iaddend. .Iadd.25.  The process of claim 24, wherein the granulation agent is introduced by spraying or by aspiration under partial vacuum. .Iaddend. .Iadd.26. The process of claim 24, wherein there is introduced one to six weight percent of granulation agent. .Iaddend. .Iadd.27. The process of claim 24, which is automated. .Iaddend. 
     
     
        .Iadd.     A vertically disposed apparatus array for the manufacture of effervescent tablets, said apparatus array constituting a tower and comprising in vertically descending order: (a) storage hopper means positioned near the top of said tower for the storage of raw materials;   (b) granulation and vacuum drying means including means for introducing a granulation agent to wet form wet granules and means for eliminating humidity from said wet granules to obtain dried granules;   (c) cooling means for lowering the temperature of said dried granules, and   (d) at least one storage container for dried and cooled granules:   said apparatus comprising also means for feeding material by gravity from said storage hopper means to said granulation-vacuum drying means, means for evacuating said dried granules by gravity from said granulation-vacuum-drying means and feeding them by gravity to said cooling means, and means for transferring granules by gravity from said cooling means to said storage container or containers. .Iaddend.   
     
     
        .Iadd.     The apparatus of claim 28, further comprising calibrating means for calibrating the materials after they leave said cooler. .Iaddend. .Iadd.30. The apparatus of claim 29, further comprising a band mixer for mixing the materials after they leave said calibrating means. .Iaddend. .Iadd.31. The apparatus of claim 30, further comprising weighing means for weighing said raw materials before any treatment. .Iaddend.  .Iadd.32. The apparatus of claim 29, wherein said drying device comprises mixing means comprising a system of mechanical stirring with lump-breaking cutters, means for introducing a granulation agent by creation of a vacuum or a spraying system supplied by a pump, means for regulating the temperature comprising a double jacket for circulating heat-exchange fluid, and vacuum means for creating vacuum. .Iaddend. .Iadd.33. A vertically disposed apparatus array for the manufacture of effervescent tablets, said apparatus array constituting a tower and comprising in vertically descending order: (a) storage hopper means positioned near the top of said tower for the storage of raw materials;   (b) a mixer-granulator-dryer device having mixing means, means for introducing a granulation agent, means for subjecting said mixer-granulator-dryer device to substantially atmospheric pressure at least during granulation and means for eliminating humidity from said wet granules material under vacuum to obtain dried granules;   (c) cooling means for lowering the temperature of the dried granules, and   (d) at least one storage container for dried and cooled granules;   said apparatus comprising also means for feeding material by gravity from said storage hopper means to said mixer-granulator-dryer device, means for evacuating said dried granules by gravity from said mixer-granulator-dryer device and feeding them by gravity to said cooling means, and means for transferring said granules by gravity from said cooling means to said   
     
     
        storage container or containers. .Iaddend. .Iadd.34.  The apparatus array of claim 33, wherein said mixing means comprise mechanical stirring means with lump-breaking cutters, said means for introducing a granulation agent comprises means for creating a vacuum or spraying system means supplied by a pump; and said mixer-granulator-dryer device includes means for regulating the temperature comprising a double jacket for circulating heat-exchange fluid, and vacuum means for creating vacuum. .Iaddend.