GB670683A - Improvements in or relating to processes and apparatus for the treatment of granular material - Google Patents

Abstract

670,683. Treating grain. DIENST, K., and DIENST, W. Oct. 21, 1949 [Oct. 22, 1948; Feb. 28, 1949; March 7, 1949; 'March 7, 1949], Nos. 27070/49, 27071/49, 27072/49 and 27073/49. Class 58. A process of treating granular material capable or incapable of flowing, particularly for the pretreatment of bread grains before grinding, comprises first subjecting the material to a vacuum, then to a steam pressure, thereupon to a sudden release of pressure, then to a vacuum and subsequently to heat treatment under vacuum and finally to a high vacuum for cooling out which is lifted after some time. As shown in Fig. 1, an apparatus for carrying out the process comprises three identical containers 6, 14, 20 fitted with heat-exchangers 9, 15, 21, and distributers 11, 17, 23, respectively, and connected by sluice valves 2, 3 and the combination being provided with inlet and outlet sluice valves 1, 4. All three containers are connected by pipes with the evacuating apparatus 7, 19. The material is evacuated in the inlet valve 1 and passes into the first container 6 where it is treated with steam at high pressure, fed through an inlet 34 and subjected to the action of the heat-exchanger 9 and passes via the connecting sluice 2 where the high pressure is lifted by bringing the sluice in connection with a condenser so that puffing of the material occurs to the second container where it is now subjected under vacuum to the heat treatment of the heat-exchanger 15. An eddying apparatus 16<SP>1</SP> is provided for the evolved steam. The material is then led via the sluice 3 to the third container 20 where it is subjected to a higher vacuum than in the second container to cool it. A modification shown in Fig. 8 comprises a single vacuum container 62 provided with upper and lower sluices 60, 61. The upper sluice 60 connected by a pipe 63 to a condenser 65, for the sudden release of steam pressure, and air pump 67, and is provided with a steam coil 70 for the initial treatment of the material with steam pressure. container can be held under increased vacuum until it has been cooled sufficiently by being connected through a suction pipe 64 to a steam ejector 71 and through condensers 66, 72 with a high-vacuum pump 73. Heat-exchange apparatus 68 is provided in the central part of the container with sufficient space above and below for the material to collect before and after passing through the heat-exchanger and below which a distributing apparatus 69 is provided. Cooling-off zones are also provided. In a further modification, shown in Fig. 14, for the treatment of granular material which becomes capable of readily flowing in the course of the treatment there are provided three sluices 95, 96, 97 as in previous modifications and two interposed vacuum containers 98, 99, the upper container 98 corresponding to those in Fig. 1 and the lower container 99 corresponding to the container 62 in the modification shown in Fig. 8. In a further modification. the containers 98, 99 of Fig. 14 are replaced by a single vacuum container 100, Fig. 15 (not shown).