Title of Invention: A DRYER AND A METHOD OF DRYING

USING THEREOF

[1] This invention is related to dryers and more specifically dryers that are used to dry pasty and/or moist foodstuff and also drying method using the same.

[2] The mentioned foodstuff can be tomato and pepper paste, various pastries and onion.

On the other hand, the dryer of this invention may also be used to dry viscous and moist medicaments, dyes and similar material.

[3] In current art, the products mentioned above were used dried in conventional ovens, conveyor ovens, drum driers however as the dry out time is considerably long, the original color and taste of the product go off and the quality decreases microbio- logically. It is possible to dry the product by maintaining the color and taste thereof by means of "spray drying method" or freeze drying method. However, those high tech methods are quite expensive.

[4] In US Patent Application No. 2002006464, a method and apparatus are disclosed to dry or heat treating the material and products in a pressure which is not atmospheric pressure.

[5] The products to be treated are loaded to the transport receptacle to be transferred to the treatment compartment. At least one microwave source is provided at the treatment compartment. A vertical conveying system is provided in the treatment compartment to maintain a recovery period after heat treatment or drying.

[6] As for the mixing mechanism that is one of the main elements of the dryer subject to this invention, there have been several solutions in the prior art. For instance in WO9316017 a mixing apparatus having a rotary shaft with blades protruding from it along the length of the shaft that is used to produce compost from waste material. The mixing elements are arranged in pairs and those result in a perpendicular moving force.

[7] In GB 1086359 a mixer for pasty material having rotors which rotate about a common axis co-axial with the chamber they are placed in.

[8] However, as mentioned above the main disadvantage of these solutions is that they are extremely expensive and the plant can only be set up for large capacities. Also, another disadvantage is that these methods cannot be used to process all kinds of products.

[9] The object of this invention is to provide a cheap and simple, highly efficient, micro- biologically reliable drying apparatus that can be integrated to a current food processing or similar plant along with the grinding, sieving and so on to obtain a homogeneous drying, in which heat and timing supervision and adjustment are easily done.

[10] The above mentioned object is attained through the present drying apparatus. The apparatus which is the subject of this application provides the granulation and drying of the product and substantially comprises a mixer that is rotatable either vertical and horizontal a motor to provide such rotation, reductors and heating and ventilating systems. This apparatus and method using thereof overcomes the disadvantages of the prior art.

[11] In the apparatus, while the mixing shaft moves/rotates horizontally, the shaft of the mixer induced by the perpendicular movement reductor rotates around its axis. Thus, the mixer blades move perpendicularly and provide the mixing and granulation of the product. The rate of motion of the perpendicular and horizontal movements of the mixer can be adjusted through controlling the rotation of the reductors and the direction of the movement can be changed.

[12] By means of a temperature probe the heat of the air blown into the product and apparatus is taken and in case the temperature exceeds the predetermined value, via a thermostatic means, required heat is applied to the product by disabling the heaters of the fan.

[13] The invention will be described herebelow with reference to the preferred embodiment with the attached drawings.

[14] In the drawings :

[15] Figure 1 is the side cross sectional view of the dryer of this invention;

[16] Figure 2 is the cross sectional view taken longitudinally of the alternative embodiment of the apparatus of this invention;

[17] Figure 3 is the cross sectional view of an alternative embodiment of the apparatus as shown in Figure 2.

[18] The reference numbers of the parts are as follows :

[19] 1 Heater with fan

[20] 2 air outlet (Air duct)

[21] 3 motor providing horizontal movement

[22] 4 reductor for horizontal movement

[23] 5 motor providing perpendicular movement

[24] 6 ragwheel

[25] 7 shaft providing perpendicular movement

[26] 8 reductor providing perpendicular movement

[27] 9 rail

[28] 10 rail/pin housing

[29] 11 mixing rods

[30] 12 shaft moving horizontally [31] 13 dryer body

[32] 14 suction fan

[33] 15 mixer

[34] 16 Lid/cover

[35] 17 fixed mixing rods

[36] 18 shaft providing horizontal movement

[37] 19 flanch

[38] The invention will be described with reference to the attached drawings.

[39] Figure 1 is the side cross sectional view of the dryer which is the subject of this invention.

[40] The dryer of this invention comprises a body (13), a cover/lid (16), one or more heat source(s) (l),a mixer (15), an air duct (2) and a suction fan (14) attached to the duct (2), motors (3,5) inducing the movement of the mixer and reductors (4,8).

[41] In the preferred embodiment of the invention the body section (13) of the apparatus is cylindrical however it may be of any other geometrical shape to attain the purposes of this invention. This body can be placed and fixed on a platform horizontally. The body can be manufactured of any stainless material suitable to the purpose of use.

[42] There are one or more heat sources are provided on the walls of said body (13) to de- humidify the water contained in the processed product. Any heating source such as a heating fan, resistance heater and microwave hater can be used. This hating source can be located to any part of the body such as the top lid of the apparatus, side walls or bottom base.

[43] In the preferred embodiment of the invention the heating source is a heating fan (1).

The heater (1) heats the material to be processed within the apparatus till the desired temperature and the temperature in the apparatus is supervised by means of a probe. As the temperature reached to the desired level, a thermostat (not shown) stops the heating process and the temperature is kept under control.

[44] The circulated heating air within the apparatus provides a highly efficient use of the air and it results in the increase in the yield. The hot air directed to the product through the heating fans placed on the top lid of the apparatus touches the surface of the product and is exhausted through the air suction fan attached to the air duct located in the middle of the top lid of the apparatus and/or side walls. This provides the circulation of the air within the apparatus.

[45] As the hot air channels/ducts (not shown) and air ducts can be located in the top lid of the apparatus, they can be placed to the side walls of the cylindrical body.

[46] The apparatus of this invention is cylindrical and placed onto a platform. The lid (16) of the drying apparatus fully opens and the product to be processed is placed there into. In the preferred embodiment of the invention, one or more heating sources (1) are provided on the lid. However, in different embodiments, one or more uniform or various type heating sources can be provided on the lid and/or in different parts of the apparatus. In the preferred embodiment, said hating source is a fan heater (1). In this case, without a need to locate and start each heater and fan separately, they can be combined into a single fan heater. With this heater fan, it is possible to direct the heat to the product and to heat the product to the desired temperature. In said lid (16) an air outlet and an axial suction fan (14) attached to it are provided. In the preferred embodiment, the air outlet (2) and suction fan (14) are provided in the middle of the lid. Thanks to this fan (14), it is possible to remove the free water molecules in the processed product out of the product quickly. In order to discharges the humid air from the apparatus, the air outlet (2) provided on the lid and/or air exhaust ducts (not shown) provided on the rim of the lid in the lid are used. Although air can be discharged from any point on the top lid, it can be provided in any other surface of the drying apparatus.

[47] Thus, the hot air directed to the product sucks the moist from the product and is discharged quickly. This shortens the drying time and contributes to maintain the original quality of the product. Thanks to the air circulation provided in the apparatus, it is possible to realize the vaporization at low temperatures and this provides to protect the original quality of the product until the end of the drying process.

[48] Another main element of the apparatus is the mixer (15) and it comprises a mixing shaft (12) and mixing rods (11) attached to the said shaft (12) with a straight angle.

[49] During the drying of the product, the mixer that can move to either direction

(horizontally and vertically) splits the product into pieces, thus the force applied to the mixing shaft (12) by the product decreases and it is possible to mix the product with a real low force. It will be possible to granulate even the hard and sticky products. Use of motors with low power helps to decrease the energy consumption and cost during mixing.

[50] In the alternative embodiment of the invention in Figures 2 and 3 a single motor (3') and a reductor are used and there are permanent scraper blades (17) fixed to the wall of the apparatus.

[51] By providing the mixer and scraper blades (H', 17') with a certain angle, the product can proceed within the apparatus easily and it will be possible to feed the apparatus from a certain point and discharge from another. Thus the continuous work of the apparatus can be managed. In this embodiment, the mixing rods (H') are located on the first part of the shaft (12') with certain design and at certain intervals. As the product that is processed in the apparatus proceeds within the apparatus, the intervals and designs of the rods may change as the humidity of the product decreases. Thus, the product can be crumbled into smallest granular size and is dried within the one and the same apparatus. [52] The mixer (15) is made of a stainless material and comprises a shaft (12) rotating with an angle of 360° horizontally and stainless rods (11; 11') located on it at equal intervals.

[53] The rods (11; 11') can be of cylindrical shape or of rectangular prism, triangular prism and so on having flat, acute, sharp, wing or blade like shapes. These rods (11; 11') are mounted to the shaft (12) as close as possible to the base of the dryer. Thus, mixing of each part of the product easily is maintained and sticking the product to the base of the apparatus is prevented. In the preferred embodiment of the apparatus, the lengths of the mixing rods (11) are the same and they are mounted to the mixing shaft (12) at certain intervals. However, it is also possible that the lengths of the rods are various and they are mounted to the shaft at non-standard intervals.

[54] The rods (11; 11') can be welded to the mixing shaft (12) or fitted to the shaft. These rods (11; 11') and shaft (12) can be of a stainless steel material. The mixer (15) can move perpendicularly or horizontally.

[55] The mixing rod (12) can extend along the midline of the body (13) and preferably parallel to the base.

[56] The shaft (7) extending from the motor (5) that is mounted to beneath the base of the apparatus, proceeds through the shaft (18) and attached to the reductor (8) that provides the perpendicular movement within the body (13) and there the movement changes its direction with 90 degrees and is transferred to a second shaft (12) and thanks to this second shaft (12) the perpendicular movement of the mixing rods (11; 11') are maintained.

[57] With a second motor (3) and reductor (4) mounted to the base of the drying apparatus a gear (6) or a pulley (not shown) alternatively can be moved and the movement of the rotating gear (6) or pulley can be transmitted to the shaft (18) providing horizontal movement by means of a chain or belt and thus the rotation of the shaft is provided.

[58] This shaft (18) can be attached to the reductor (8) providing the perpendicular movement by a flanch (19) mounted to the shaft (18) and thus the reductor can rotate around its axis. The rotation of the reductor (8) around its axis causes the horizontal movement of the mixing shaft (12).

[59] The horizontal movement of the mixing shaft (12) and perpendicular movement of the mixing rods are supervised with the invertors (not shown) selected according to the power of the reductors (4,8) and the movement speed thereof can be adjusted.

[60] As the mixer can mover in two directions continuously, the product can be dried ho- mogenously. In the prior art mixers where the mixers can only move horizontally, during the process of drying consistent products such as tomato paste, dough etc. The locking or immobility of the mixer due to excess load on it or necessity for high power motors can be eliminated with the mixer disclosed here. [61] In the apparatus, thanks to the rail (9) attached to the inside of the apparatus and rail housing (10) provided on the mixing shaft (12), mixing shaft (12) is guided in the rail.

[62] Thus, during the drying of the hard and resistant products, the risk of unbalancing the mixer by forcing the mixing shaft is prevented.

[63] With the present apparatus, a crucial advantage is that depending on the desired specifications of the resulting product, the adjustment of heat is easily achieved during the drying process.

[64] Another advantage of the present apparatus is that the product is dried in a very short time and thus the product quality is really high. In the prior art apparatus, as the food products are dried up in considerably long time under low temperature, the quality is impaired. In the present apparatus it is possible to even dry delicate products such as tomato paste etc. in a fairly short time with high quality.

[65] The drying process realized in the above described apparatus substantially comprises the following steps:

[66] a) feeding the product to be dried and processed from the lid/cover of the drying apparatus,

[67] b) exposing the product to be processed to the drying and mixing processes and determining and adjusting the parameters such as mixing speed, mixing temperature etc.

[68] According to the type of the processed product,

[69] c) Transferring the product having a certain amount of moisture (10%-15%)from the drier to a hammer mill and milling until the particulars are of 4-40 mesh size,

[70] d) Transferring the product from the mill back to the drier and exposing the same to the drying process so that the moisture content is about 6%-8% and repeating these steps as long as required depending on the desired qualifications of the product, minimizing the particulate size to 40-100 mesh and continuing the drying process until the desired moisture content is achieved, ending the drying process.

[71] In the present apparatus, with the process described above, for instance during the process of recovering tomato powder from tomato paste, the crusting on the surface of the product is constantly broken by the mixer (15). In case this breaking cannot be realized; some problems such as stopping the drying process, prolongation of the time and darkening of the product as it is exposed to heat constantly, may be encountered.

[72] The tomato powder granules recovered at the end of the drying process have moisture of 10% to 15%. With a hammer mill (not shown) attached to the apparatus, these granules are broken and a powder of 20-60 mesh size is obtained.

[73] After the granules are ground as a fine powder, if the process is continued, it will be possible to obtain a tomato powder having moisture content of minimum 2 - 3%. As the moisture content of the product is lower, there may be powder losses from the air duct (2). The duct is attached to a cyclone to keep the escaping powder. Thus the product waste is lowered.

[74] Thanks to the present process and apparatus, the start up investment is quite low and as there is no need to work with full capacity, it is possible to realize the investment for this process and apparatus in medium size and small enterprises. Since the set up time of the plant is quite short, the capacity of the plant can be increased gradually as need arises.