DE838244C - Method and device for heat treatment in a vacuum, in particular to improve the grinding and baking ability of bread grain - Google Patents

Description

Methods and devices for heat treatment in a vacuum, in particular to improve the grinding and baking ability of bread grain 1) The invention relates to a method and directions for continuous heat treatment \ -oii bread grain for the purpose of improvement the grinding and baking ability. The best capable of painting It is a prerequisite that what is to be ground Grain a single particular. Humid keitsgelialt, which has so-called grinding moisture. the 1 (alil moisture of the grain is also not for every mill is the same, depending on the climatic tischert \ 'erliiiltnis @ s, eii of the mill, according to which special Verinahlungsmethoderi etc. different st ° in. Anyway, it is the purpose of the invention the simplest `` ice to the grain to those damp- salary to give that for the mill, in that it should be ground, the best quantitative and ilu; ilitati @ - <n flour yields guaranteed. In the raw grain to be ground, the moisture content of the grains is known to fluctuate between two and a half and twenty-one percent, while the fluctuations in the best moisture content for grinding (grinding moisture) are between 15 and 17010. This grinding moisture is to be taken as a basis, whereby it should be noted that for each mill the grinding moisture is to be precisely set to tenths of 1> roz-duck and must be paused. Likewise. but the moisture content of this grain to be treated should also be balanced from grain to grain so that it is uniform. The best grindability also means that the grains are evenly soft and crumbly so that they can be grinded without too much pressure, which is not only in the interests of good baking quality, but also saves energy. It is necessary that the cereal be best baked at higher temperatures. treated warm, in order to achieve the best swellability of the adhesive, whereby the type, dry and wet exposure, as well as the duration of this exposure is also limited. In addition, the grain must be sufficiently cooled for the grinding, a tough outer shell of the grain should be achieved in order to achieve purer flours with little ash.

The object on which the invention is based therefore consists in both Grain that is too dry to achieve the most favorable end results with appropriate To enrich moisture under the influence of heat as well as to moist grain the to remove excess moisture under the action of heat, at the same time the To compensate for differences in the moisture content of the different cereal grains and finally the maintenance of the appropriate temperatures and their Specify or limit the type and duration, with a precondition for this overall task is that they basically follow a uniform procedure and in one and the same Device, albeit of different design, can be carried out.

So far one has tried to solve this problem by doing everything Grain to be treated by netting, washing and allowing to stand until swelling loaded with excess moisture, then the excess moisture through Heat in the vacuum is withdrawn again and finally the excess heat in special Removed cooling devices. This method has the disadvantage of being too serious Exercising takes a lot of time and usually takes up large space-saving containers take and are expensive to produce, and that it is not continuously carried out is. Also, there is a significant cost to withdrawing all of the excess Moisture and the excess heat required.

These disadvantages are avoided by considering the grain to be treated the dosed moisture for the desired grinding moisture charges what before or can be done during the vacuum treatment, so that the desired grinding moisture with! this charged moisture is practically not exceeded and then The grain progressing without standing in the trickle process under vacuum a step-by-step adjustable heating in the presence of supersaturated water vapor exposed for a period of time at elevated temperatures. The vacuum is in the capillaries the grain removes the air cushion, so that the water or water vapor diffusion This promotes the swellability of the adhesive and the absorption of moisture in the interior of the grains and the moisture balance between the grains favorable influenced. The moisture exchange takes place as a result of evaporation and condensation from the oversaturated water vapor in the shortest possible time, what after the previously known The process can take hours, even days, so that the costly standing container can be saved and time is also gained. On the other hand, the paragraph-wise Effect of maximum vacuum in the same process step with the lowest possible cost destroy the excess heat, while at the same time a precisely known numerical value Well, evaporation of a small amount of moisture occurs, through which the grains remain largely mellowed, whereas the outer layers of the grains due to the) the inner core displaced moisture in contrast to air drying, in which the One-sided drying makes the peel brittle and fragile, it remains tougher. As is well known Well-mellowed grain grinds easily, and a tough shell prevents that this is crushed and splintered during grinding. As a result, carries through the effect of the maximum vacuum also contributes to the cooling achieved, that an improvement in the grinding and baking ability of the grain to be treated is achieved. Since this cooling takes place directly in the same operation, wherein If the grain still has a considerable amount of internal heat, this is related the more effective on cooling.

It is advantageous to practice the new method in such a way that the grain to be treated is heated and then trickled through a section of space leaves, in which an expediently generated in the same vacuum space zone with supersaturated Water vapor is maintained. For example, you can get one for this known vertical vacuum apparatus designed as a trickle dryer with a loading container arranged at the top, one arranged at the lower end, Removal container and one lying between these two containers on both sides operate heated vacuum container equipped with lock containers, which is in three room sections, one for untreated, one for in-treatment and one for treated goods. With one of these. Vacuum apparatus one must ensure that in a Part of the vacuum container always has a zone of supersaturated Was.serdampf available; where the zone is for a higher or lower section of space as desired the vacuum container can be adjusted; d. H. it should not be fixed, but rather be variable.

The zone of supersaturated water vapor in this vacuum apparatus can be created in that. the material to be treated is either wetted with water for the purpose or shortly before it is introduced into the apparatus. washes or only adds water to him in the treatment room. This water charged to the cereal grains is initially absorbed by them under the action of the correspondingly heated radiators, but then partly in the deeper zones of the vacuum container due to further heating Water vapor transformed when pulling upwards in the higher zones the grain trickling down counteracts this and thereby through condensation saturate again gives moisture back, whereby then also the complete compensation of the different where the degree of moisture in the grains takes place- hirdet. This is used to generate this Water vapor expended amount of heat again v () 11 recovered, which is advantageous because the ]) The effects achieved during the treatment are practical can be done without any effort. 1) he can handle 13handling, to compensate for any fluctuations during the treatment ganges, also by introducing it appropriately () 1i live steam in the deeper zones of the \ -: iktitttnlyeliiilters are supported, where the I, 'riscli, <lampf mit- has a more regulating function. l), there is agitation of the (#etreidemisclitnil; in front of the lead the Itulige # treides in the Vakutima.pparat as aitrli des @ inleitc # tis vott live steam during the I do not need to do anything, of course, tvciiii the mixture of grains inside the grain brrcits brings more moisture with it than that g @ et @ ün, _- requires the right grinding moisture, whereby the after your balance of moisture between all grains any excess moisture as vapors in the upper kauni section of the vacuum is discharged. I) the supersaturated water vapor zone in the \ 'akutinia1) 1) arat can be used for the Well-known stone temperatures between 3o and 7o ° C urirr but also even higher due to the gradual bare 1 # .setting (k, r temperature of the radiators, by adjusting the air dilution, whereby one zt @ cckniü (.iig das \ "al: ttutn the treatment tcnil) eratur adapts to the prevailing steam tension, and by adjusting the flow rate ini regulate the outlet of the vacuum container so that the cheapest grinding technology and chopping properties. Does it during the heat treatment of the goods in the \ 'ctkuuinapparat around a even temporarily non-pourable goods, so one uses special ones Lock containers and special lock devices directions or arranges on the one hand between the Loading container and the upper lock container of the apparatus and on the other hand between the upper lock container and the upper one chewing section for untreated goods in a vacuum i ::! li: filter in addition to the built-in double flow valves or instead of these .Otid (-re conveyor devices. On top of that, builds matt in the upper section of the vacuum I) cliälters a heat treatment device, e.g. B. a plate heater so that above and below this device a space for each Receipt of good remains free. Temporarily not pourable material is z. B. freshly washed grain with much more clinging Parboiled or parboiled rice immediately after the cooking process. The upper one Lock containers in the vacuum apparatus can be also train as a centrifuge and if necessary Connect a toothed roller, a mixing tub and a pump with a pipeline, one behind the other, between the charging container of the apparatus and the centrifuge.

The plate heating device can also be removed from your vacuum container Trickle dryer, blow it out and install it in its own vacuum container and then this vacuum container via an intermediate lock with the vacuum container of the Bring trickle dryer in connection. So that the whole vacuum apparatus germinates If the overall height is too great, the upper part of the vacuum apparatus can be opened up to the newly switched middle lock container including disconnect and as Arrange twine next to the rest of the vacuum apparatus when going to the transfer of the goods from the middle locks, bxli: filter into the upper section of the Vacuum containers, rs built in between a higher conveyor, which serves to maintain must be encapsulated in a vacuum.

In order to subsequently cool back the goods treated in the vacuum apparatus, You can do that so that it loads the machine in a cold and easy-to-grind state in one and the same apparatus and in one and the same treatment course with little -laterialaufwa.rid, at low cost, without any appreciable increase in height of the apparatus and without downstream a special cooling device with their reach special devices and specially actuated mechanisms, if you the exiting from the lower space section of the vacuum container in the good lower lock container located between the vacuum container and your removal container exposed for a long time to a high vacuum, which is higher than that in the vacuum container prevailing vacuum.

The result is a vertical standing and as a Riosel dryer trained vacuum dryer, in which the capacity of the between the vacuum container and the lower lock container lying on the removal container so far. enlarged is that the property to be treated is in it for a longer time than usual, must linger, and in which the lower lock container to an evacuation device is connected, which creates a higher vacuum in this container than in the vacuum container. The outlet valve of the lower lock container must be controlled in such a way that that the lock container each several beds from the space section for can accommodate already treated material of the known vacuum container.

With that, however, the play of the valves in the whole apparatus despite the Condition for the goods to remain in the lower lock container for a longer period of time can remain the same, similar to a device without an enlarged bottom Lock container, it is advisable to use the lower space section in the vacuum container to be chosen accordingly as large, so that as much material accumulates in it in each case can, as in the ones below located enlarged lock container has space between two actuations of the lock valves. The amount of this eligible goods depends on the level of the temperature of the goods at Entry into the lock container and; its reaching through a certain vacuum Cooling temperature. Because the cooling device compared to the known vacuum dryers with attached special cooling device due to its arrangement in the lower Lock container according to the present invention very close to the heating device this vacuum container moved empty in the space section for items being treated is, then the intrinsic heat of the good has not experienced any reduction, which for the effectiveness the cooling of the goods to be treated is of great importance. Be at the same time in the case of a new vacuum apparatus with the specified cooling device compared to one known vacuum apparatus with an attached vacuum cooling chamber, which is also formed is like the vacuum container of the vacuum dryer, the space sections for the untreated and for the treated material in the cooling chamber and the internals with the discharge device saved in it, which is a very significant saving in material and overall Height means. In the case of the vacuum apparatus, the cooling is of essential importance in the lower lock container that this can easily be done in the normal operating mode of the vacuum dryer can be achieved if you only take care that the used evacuation device in the lock container a higher vacuum can create than prevails in the vacuum container.

Appropriately, one connects the upper lock container, the is arranged between the feed container and the vacuum container and the you can give the same content as the lower lock container with the same Evacuation device that creates the vacuum in the lower lock container, what the advantages with it that the material to be treated is pre-evacuated more effectively than before and that the control of the evacuation device becomes simpler and more convenient. Finally, one can use the upper space section provided in the vacuum container also enlarge so that its holding space corresponds to the lower space section and the holding space of the lower lock container.

In the drawings, some exemplary embodiments are in schematic form Longitudinal sections shown. In the vacuum apparatus (Fig. I) a distinction is made between the following communicating containers or spaces: a loading container i, an upper lock container 2, a space section 3 for untreated goods, a space section .4 for items being treated, a space section 5 for items that have already been treated, these three room sections are all in the vacuum container 6, a lower lock container 7 and finally a removal container B. The Evacuation of the vacuum container 6 takes place through a suction pipe 9, which is from the upper At the end of this vacuum container 6 passed through a condenser io to an air pump is. As a result of the action of the air pump, it becomes that in the deeper part of this room 4 vapors generated by the radiators located there i i through the above the feed container i supplied, then the upper lock container 2 passing through and cool grain flow entering the room sections 3 and 4 one after the other inevitably countered, so that in a higher part of the space section 4 of the vacuum container, 6 dtie zone with supersaturated water vapor arises in which the influence of the cereal grains by condensing on the cool cereal grains Vapors take place, the temperature of which is determined by the radiators in room 4 and by the setting the appropriate air dilution can be regulated. The trickle speed is the middle by influencing a discharge device 12 at the lower end Room section 4 is set.

The radiators i i, which are made up of individual elements arranged above or below one another There are heating elements whose temperatures can be controlled independently of one another are expediently made of annularly curved, arranged side by side Pipe layers or pipe coils with pipes of round or oval cross-section, the are surrounded to the outside by a vacuum-tight, easily insulated jacket, while it opposite the core formed in its center, which is useful as a walk-in shaft is designed, are so closed that the vapors inevitably the grain flow is countered. It is of particular importance that with this arrangement the formation of condensation water necessary for the aim of the treatment, namely a uniform to maintain a balanced mix of grains,. is particularly harmful, advantageously is completely avoided.

At the end of the two lock containers 2, 7, which together or can be connected separately to an air suction line, two valves each serve I, II or III, IV, which can be operated, for example, from a single drive can.

The valves I, 1I (FIG. 2) can be conveyed by conveying devices 14, 1 5 any training can be replaced, which is the good from each above Transfer room i or 2 to room 2 or 3 below.

The upper space section 3 of the vacuum container 6 for untreated goods eats so large that in it a particularly step-wise adjustable heat treatment device 13 can be accommodated. This heat treatment device may be a plate heater be. This inserted heating device 13 is the enlarged space section 3 of the vacuum container 6 has been divided into three space sections 16, 17, 18. Of the Space section 16 above the heating device 13 is used to accommodate untreated Good. Of the at the level of the plate heater 17 contains goods in pretreatment, while that which enters space 18 Has already been well pretreated and thus pourable.

The conveying devices 14 and 15 can, for example, consist of toothed Drums or toothed rollers for dividing the coherent material and from subsequent There are screw conveyors that convey the divided material into the adjoining rooms.

The new vacuum apparatus, which is also used for drying, has the advantage on that the heat treatment making the material flowable on the plate heating device 13 in the upper enlarged section 3 of the vacuum container 6 under the same negative pressure takes place, which prevails in the vacuum container 6 itself. The temperature of the heating medium for the plate heating device 13 can be regulated step by step from plate to plate that the property does not suffer in its quality due to the action of heat. The further treatment course in room section 4 closes without any further special Effort and without wasting time or heat.

For wet, softened or washed grain that does not initially trickle, it is advisable, instead of special sluice devices, to use a centrifuge 19 (Fig. 3 ), which is connected, for example, to the upper space section 16 of the vacuum container 6 by a feed screw 2o. In this case it is expedient to give the grain to a loading container i, from which it arrives at a toothed roller 21. The material thus divided then falls into a vat 22, in which it is mixed with enough water so that in this state it can be fed to the centrifuge 19 by a pump 23 and a pipe 24, the height of which is ensured by the vacuum. From the centrifuge 19 the thrown grain passes through the screw conveyor 2o into the upper space section 3 of the vacuum container 6, where it falls onto the plate heating device 13 and is conveyed on evenly distributed by an agitator on these plates and finally via the space section 18 to the space 4 of the Vacuum container 6 delivered. will. Due to the action of the appropriately regulated temperature of the heating medium, the still adhering water can be absorbed into the interior of the cereal grains on the plates of the heating device 13, causing them to swell, i.e. initially being loaded with excess moisture inside. By transferring the water into the interior of the cereal grains, it becomes free-flowing. As a result of the subsequent evaporation of the excess moisture from the interior of the grain under vacuum, which takes place in space section 4, this becomes crumbly and easily grindable, which is advantageous. The brothers generated during the evaporation of the excess moisture, which is led upwards in countercurrent to the trickling grain, in contact with it, balances the moisture content of the individual grains and, through its appropriately regulated temperature, influences the baking properties of the processed grain.

If you want to pretreat the grain on the plate heater 13 carry out at a pressure of the negative pressure prevailing in the Vakuvanbehälaer 6 differs, it is advisable to attach a to the lower end of the space section 18 Lock container 25 (Fig. 4) and wipe this and the space section 4 of the vacuum container 6 for items being treated still has a space section 26 pretreated for slides from the lock container 25 and into the Treatment room section 4 of the vacuum container 6 entering goods vomusehem this Lock container 25, the upper and lower end with simple passage valves can be equipped, enables the transfer of the plate pickling device 13 Gutces treated in the treatment room 17 in the room section 26 without compensation of the vacuum between the container parts 3 and 6.

There is a vacuum dryer built in this way and designed as a trickle dryer occupies a large overall height, it is useful to place the vacuum dryer between the locked lock container 25 and to share the space section 26 and both Apparatus parts, such as Fig. 5 shows to be arranged side by side and for transferring the Good looking. the space container 25 in the space section 26 an encapsulated bucket elevator 27, e.g. B. to use a vertical scroller, which can be ge @ efizb under vacuum. This arrangement has the advantage that the valve drives are right next to each other lie and can thus be more easily summarized, operated and monitored, as if one lock container above and the other below the vacuum container 6 is arranged.

The lower lock container 7 in the example in FIG. 6 is enlarged according to the invention to carry out a re-cooling of this material under increased vacuum so that the material to be treated has to stay in it for a longer time than usual. A condenser 39 with a vacuum pump 40 for evacuating the vapors is connected to the vacuum container 6 of the vacuum dryer, while a steam ejector 41 and a special condenser 42 with a vacuum pump 43 are connected to the enlarged lock container 7 to achieve maximum vacuum. A two-stage vacuum pump can also be used to achieve the maximum vacuum. According to Fig. 7, the capacity of the space sections 3 and 5 and this upper lock container 2 are selected as large as the capacity of the lower lock container 7 serving as a cooling chamber, so that a vacuum dryer with enlarged spaces 2, 3, 5, 7 and a Wärmebehamilu ngsraum 4 normal size arises. Through this. it is possible to connect the upper lock container 2 with the lower one so that both can be brought to the highest vacuum at the same time via the same evacuation device, whereby the operation of the newer vacuum trickle dryer with. Cooling device can be carried out in the same way as that practiced with other vacuum dryers.

Claims (7)

i. Process for the continuous heat treatment of bread grain for the purpose of improving the grinding and baking ability, characterized in that that the grain can be washed, wetting or steaming before or during the treatment the amount of moisture dosed for the desired grinding moisture under vacuum charges and this under vacuum through heat effects in the interior of the cereal grains, that are moved over or on the heated surfaces, drift in, serve on them Grain moved continuously beyond the grinding moisture Moisture can evaporate with further heat effect, while doing so educated brothers towards the continually moving downward flow of grain which creates a zone with supersaturated water vapor, which balances out this accelerates the moisture content between the grains. 2. Device for Exercising a method according to claim i, characterized by a vertical upright vacuum apparatus provided with trickling devices with a top-mounted vacuum apparatus Loading container (i), a removal container (8) arranged at the lower end and one between these two containers l, in, on both sides with lock containers (2, 7) equipped stepwise heatable vacuum container (6), which is divided into three Room sections, one for the untreated (3), one for what is being treated (4) and one for items that have already been treated (5), with the radiator In the space section (4) to form a zone, supersaturated .Waterdampf rides laterally closed and practically only at the bottom, and open at the top and. the brothers deduction (9) proceed in the upper part of this vacuum container (6). 3. Apparatus according to claim i and 2, characterized in that the individual radiator (i i) forming Heating elements made of tube layers bent into a ring and arranged next to one another: or Coils exist and are arranged in such a way that they can be isolated to the outside through a vacuum-tight jacket and inside through a heated cylindrical insert, which serves as an inspection shaft, are protected to prevent condensation. 4. Apparatus according to claim 2, characterized in that between the charging container (i) and the upper lock container (2) and between this and the upper space section (3) this vacuum container (6) is a heat treatment device that can be heated in stages, (i3) e.g. B. a Tellerheizvorsichtung on plates arranged one above the other, so it is provided that above this Wärmebehandlungsvor: direction (i3) a space section for untreated. Good (i6) and below the heat treatment device (i3) a roughness for already pretreated goods (i8) remains. 5. Apparatus according to claim 2 and 4, (characterized in that the vacuum container (6) instead of the upper lock container (2) a centrifuge (19) is connected upstream. 6. device after; Claim 2 and 4, characterized in that the vacuum container (6) with the centrifuge (i9) a pipeline (24), a pump (23), a mixing tub (22) and a toothed roller (21) are connected upstream, which are fed through the feed container (i) receives. 7. The device make claim 5 and '6, characterized in that between the space section (i8) for receiving pretreated goods and the space section (4) this vacuum container. (6) for goods in Ferbigbehandr development a, lock container (25) and then a space section (26) for receiving this from the Schleusenr container (25) exiting pretreated, and gradually into the treatment room section (4) is arranged trickling in. B. Apparatus according to claim 7, characterized characterized in that the upper part of this vacuum dryer to the middle lock container (25) including as a whole arranged next to the remaining part of this vacuum dryer, and in between a height conveyor (27) is switched on, -der for the purpose of maintenance a vacuum can be encapsulated. 9. The device make claim i, 2 and 4, characterized characterized in that the capacity of the between the vacuum container (6) and dernEntarahenebehospital (8) lying lock container (7) is enlarged so far that this is to be treated Well in it a longer time than usual eats, must linger and that this one Lock container (7) connected to an evacuation device (4i, 42, 43) is that in this. Container creates a higher vacuum than used in the vacuum container will. to. Device according to claim 9, dadhxrch marked, that the space section (5) for already treated material in the vacuum container (6) about has the same capacity as the lower lock container (7). i i. contraption according to claim io, characterized in that the space section (3) for untreated Well in the vacuum container (6) and the upper lock container (2) the same capacity Has. 12. The device according to claim t i, characterized in that the upper lock container (2) is connected to the same evacuation device (4i, 42, 43) that the lower lock container (7) evacuated.