US1281234A - Apparatus for drying wet of watery materials. - Google Patents

Description

J. R. VAN MUSSCHENBROEK.

APPARATUS FOR DRYING WET 0R WATERY MATERIALS APPLICATION TILED FEB. 4. 1918.

1,281,234. Patnted 0ct.8, 1918.

2 SHEETS-SHEET l.

1. R. VAN MUSSCHENBROEK. APPARATUS FOR DRYINIE WET 0R WATERY MATERIALS. APPLICATION FILED FEB. 4. TIME.

1,281,234. Patented Oct. 8,1918.

2 SHEETS-SHEET 2- JAN RUDOLPH VAN MUSSCHENBROEK, OF THE HAGUE, NETHERLANDS.

APPARATUS FOR DRYING WET OR WATERY MATERIALS.

Specification of Letters Patent.

Patented Oct. 8, 1918;

a Application filed February 4, 1918. Serial No. 215,360.

To all whom it may concern Be 1t known that I, JAN RUDOLPH VAN MUsscnnNBRonK, engineer, of 140 Copernicusstraat, The Hague, Netherlands, have in-' vented certain new and useful Improvements in and Relating to Apparatus for Drying Wet or Vatery Materials, of which the following is a specification.

This invention relates to improvements in processes for drying wet or watery materials, such as fruits, especially cocoanuts, but also tealeaves, berries, raisins, currants, all kinds of vegetables and other products and articles and to apparatus for carrying this process into effect.

Heretofore it has not been possible to efl'ectually dry watery materials, as described above, on a large scale and in such a way, that the said drying did not affect the quality of the product itself and that every elemental part of the material is separately exposed always to such conditions ofdry-'. ing as at any moment would be most suitable for the quality of the product. In one known process the material to be dried is spread out in a room in layers of undefined thickness and dry, hot air is passed through the room, while the material is left therein until it is dry. Another method is founded on the principle of counter-current; the air which is still fresh is brought to act upon .material which is nearly dry and the air which has nearly lost its drying-power is brought to act upon fresh material.

It is clear that neither of these methods answers the condition that at any separate moment every elemental part of the material should be dried under such conditions as are most favorable at that moment; if for instance the material to be dried is spread out in layers and the bottom part of a layer is acted upon by air 'of the right temperature and the right degree of humidity, this air, on reaching the upper parts of the layer, is already cooled down by having absorbed water vapor to a great extent. If then the temperature of the drying alr should be raised in order to produce efiicient drying of the top part of the layer as well, the

bottom part will be too strongly heated.

Especial with products like cocoanuts, whose va ue decreases very much if the right temperature is but sli htly exceeded, the drawbacks of such de ective methods are very great. The methods which are based on the principle of counter current partly possess the same and partly other drawbacks.

In this invention endeavor is not made, as in the usual methods, to make the most of the heat and the drying-power of the air; its principle on the contrary is to keep the conditions of drying between narrow limits by bringing every elemental part of the material to be dried separately into contact with air of such temperature and such degree of humidity that the said temperature of every elemental part during the drying process remains between such elements as have been found to be best suited for the kind of substance under treatment; the degree of humidity being at the same time such a one as to produce a really efiective drying. To achieve this purpose the material to be dried is spread out in layers of elemental thickness; e. that no two elements are placed-one on top of the other; l

humidity after regeneration.

For the repeated heating of the air to'the required temperature devices of a known kind may be used. For instance heating pipes, whose temperatures may be regulated according to requirements, may be placed between any two layers of the material to be dried, and the air, on passing from one la er to the other, passes along these heating pipes. According to my invention the re-. generation of the air as to its degree of humidity may be practised by passing the air over or through endless hygroscopic cloths, tissues or the like, which tissues, cloths or the like, are partly inside and partly outside the drying room and are moved by rollers outside this room. That part of the cloths, tissues or the like, which is inside the drying room is situated between two layers of the material to be dried and wholly or partly absorbs the water va or contained in the spent drying air. Outs1de' the drying room devices are arranged to wholly or partly remove the absorbed water friom the hygroscopic tissue, cloth or the li (e.

In the accompanying drawings a schematic example is given as to how the invention may be carried into practice.

Figure 1 is a conventional representation of a drying house in which a large number of trays are disposed, the detail construction of the trays being shown in Fig. 2.

Fig. 2 is a detail of a tray with the device for supplying and discharging the air.

Fig. 3 is a drying house, partly in detail and with some pa.- ts cut away, in which the same air is used for several drying trays placed one above the other. while between any two trays the temperature of the air can be exactly regulated according to the requirements, 2'. e. with relation to its degree of humidity at that moment and with rela tion to the nature of the material to be dried.

Fig. 4 is a device according to Fig. 3. in which the degree of humidityof the air can also be regulated by means of hygroscopic tissues, cloths or the like.

In Figs. 1 and 2 the air is supplied through a tube 1, which divides into vertical supplying channels 2. These supplying channels feed air pipes 3, by. which the air by means of partitions 4, is equally divided under the perforated gauze or wire gauze bottoms 5 of a low tray 6. This tray (or a horizontal row of trays) is movable on slides 7, so that it can easily be removed from the house and emptied. while at the other end of the house another tray (or another row of trays) with fresh material is pushed in. The spent air is removed by an air tube, which may also be provided with conducting partitions 9, the latter preventing thespent air from one part of the tray hindering the free passage of the spent air from another part of the tray. Finally the spent air is conducted through the channels 10 to the collecting channel 11, which may be connected With a suitable regeneration device (not shown); In the apparatus according to Fig. 3 the hot air is supplied by two channels 12, which are divided by partitions into vertical shafts 14. In these shafts the trays 6 are placed. Each time the air has passed a -tray it is heated again by tubes 15, which are supplied with low pressure steam. The temperature of these tubes may be exactly regulated by regulating the steam supply. The tubes 15 are supplied with steam from a suitable source, for instance, from a pipe 19 having a regulable valve 20 therein.

The spent air escapes through the roof. It stands to reason that the top trays need not be exchanged so often for fresh ones, as the bottom. trays.

In the apparatus according to Fig. 4 the device according to Fig.- 3 has been made fit for drying such materials requiring a minimum of humidity in the drying air, by providing ever moving drying tissues, or cloths 16, of ahygroscopic material-cotton, wool or the like, or a doubletissue containing a salt or another suitable material, which has the property of absorbing water vapor. The tissues are dried again by heating them by means of steam pipes 17 in therooms 18,situated between every two drying departments14. as well as on both sides outside the drying house.

It is self-evident that the material to be driedmay be treated in another way than by putting it into trays. If the nature of the material permits, it may be suspended from endless belts, which are passed through the drying room. Finally a drying depart ment may consist of several sections for drying those materials which require to be dried in several stadia under different conditions. especially as to temperature, onaccount of the fact that the properties of these materials gradually change as the drying process proceeds.

All such forms of executing the processv are intended to be covered by my claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is 1. Apparatus for drying watery vegetable material which consists of a plurality of separate tiers of trays, means for con veying air to each tier below the lowermost tray, means for heating the air as it passes from one tray to another, and hygroscopic elements for depriving the air of its moisture as it passes from one tray to another.

2. Apparatus for drying watery vegetable material, which consists of a plurality of separate tiers of trays, means for conveying air to each tier below the lowermost tray,

means for heating the air as it passes from one tray to another, and means for depriving the air of moisture as it passes from one tray to another.

3. Apparatus for drying watery vegetable material, which consists of a plurality of separate tiers of trays, means for conveying air to each tier below-the lowermost tray, means for heating the air as it passes from one tray to another, hygroscopic elements for depriving the air of its moisture as it passes from one tray to another, and means for driving the moisture from said hygroscopic elements.

4. Apparatus for drying watery vegetable material, which consists'of a plurality of separate tiers of trays, means for conveying ends of said belts for driving the moisture from theasame. p

5. Apparatus for drying'watery vegetable material which consists of a plurality of separate tiers of trays, means for conveying air to each tier below the lowermost tray therein, heating pipes arranged between a drying house and in which the hot air forming the drying medium is supplied to the material to be treated and removed and regenerated when spent by'an arrangement comprising air inlet pipes fitted beneath the trays divided at equal intervals by partitions, which directthe hot air upward and through the material to befitreated and exhaust or outlet pipes, similarly partitioned, for conducting the spent air from the trays to a regenerating chamber, where it is reheated, the means for reheatin the spent air comprising tubes arranged etween' the layers of trays branchihg off at every layer from a common steam supply pipe, the steam supply beingfthen controlled, and the means for regulatlng the degree of humidity of the spent air comprising endless drly'ing tissues or cloths of hygroscopic materia ranged between the layers of trays and-movable over rolls in-such a way, that the cloths can be dried'by suitable arrangementsoutside the drying chambers.

In testimony whereofI afiix my signature in presence of a witness.

, JAN aunotrn'm musscurunaorx.

Witness:

PLANTQ Fr'mrnm.

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