EP0120984A1 - Process and plant for debenzinizing residues resulting from organic solvent extraction of vegetal raw materials that contain oil and fat - Google Patents

Abstract

When de-benzinating residues containing solvents that occur when organic, vegetable and oil-based raw materials are extracted from organic solvents and from which the oil-based or so-called Miscella has been separated, the actual de-benzinization is carried out by the direct action of a de-benzinating agent, especially water vapor Upstream pre-gasoline with indirect heat transfer, especially indirect steam heating, relieves the load on the entire system and thus considerably reduces it. In addition, the subsequent drying and cooling of the now solvent-free residue can be carried out in a single, combined stage, thereby further relieving both the scope of the apparatus and the energy expenditure.

Description

When vegetable, oil and fat-containing raw materials such as oil fruits and oilseeds are extracted with organic, in particular polar, solvents in order to obtain oils, fats and phosphatides (lecithin), the solution of oils, fats and phosphatides in the solvents called Miscella is obtained and on the other hand, an oil- or fat-free or oil- or low-fat residue, the so-called shot.

This residue, which for example can still have up to 0.5% by weight of residual oil and up to 30% by weight of solvent, is after the separation from the Miscella by pressing or sieving in a predominantly continuous process using steam or water Fluids containing water vapor are treated and freed from the solvent to an optimal degree.

The proportion of solvent in the solvent-wet residue, the scrap, naturally depends on the type of solvent or extracting agent, the raw material, the extraction process with its special process parameters, etc. and can fluctuate within certain limits. However, it is not only necessary for process economy reasons to drive the solvent out of the scrap and to recover it optimally, the scrap itself, which is mainly processed for feed and food, can only be used if it is used for further processing practically solvent-free. The relevant industry predominantly uses aliphatic hydrocarbons, in particular technical hexane (n-hexane) as an extractant for oil crops and oil seeds. Depending on the structure, this hexane has a boiling range of approximately 63 to 70 ° C.

It goes without saying that other extraction agents such as pentanes, heptanes and the corresponding iso compounds or mixtures thereof are used depending on the raw material and the extraction process. However, the technical hexane of the above specification has proven to be particularly suitable in particular in the case of oil and fat extraction from soybeans, cottonseed, beech nuts, linseed, rapeseed, sesame, sunflowers, etc., so that the invention is based, for example, on the extraction of soy material with the aid of. Hexane is described.

Since the technical solvents such as hexane etc. are referred to as gasolines by the relevant industry, the desired improved and thus inventive process of expelling hexane from the residue from the extraction is referred to in general and in accordance with the technical terminology as petroleum spirit.

Suitable methods and devices for the de-benzinization of residues from oilseed and fruit extraction, the so-called meal, have long been known. Devices of this type are offered by the relevant industry under the terms toaster, mineral spirits, dryers or steamers in many more or less powerful designs. The meal is freed of the extractant with hot air, steam or other suitable fluids in predominantly continuous operation, and at the same time the extractant is recovered.

For example, US Pat. No. 2,585,793 describes a toaster developed in particular for extracted soy flakes, in which in the upper region of a multi-day system, the de-gasification takes place by feeding in direct water vapor. In the device according to US Pat. No. 2,776,894, the uppermost of a multi-floor system is provided with steam outlet openings, so that the goods placed on the top floor are directly exposed to the steam. According to DE-PS 26 08 712, the direct steam is introduced via the bottom container bottom, which is designed as a perforated or sieve bottom, and is guided towards the goods from bottom to top over the entire container height via likewise perforated floor bases.

From "Fette-Seifen-Anstrichmittel" (1976), 2, p. 56 uff. is now a worldwide used "toaster", in which the continuously coming from the extraction, gasoline-containing meal on the top floor of a multi-stage system is treated with direct steam (water vapor), the steam being introduced laterally into the double floor and over a variety of holes is evenly distributed over the entire floor cross-section. Part of the steam condenses in the grist, another part escapes as vapors with the solvent, the gasoline, and is passed on to a gasoline-water separator as condensate

The double floor of the top floor - and all other floors - contains a lock, through which the de-petrified shot falls continuously into the floor below, the so-called drying. The speed of the lock (s) enables a certain material level to be set on the individual floors.

The dryer floor, which is connected after the gasoline removal, is also delimited at the bottom by a perforated floor designed as a double floor, through which hot air is introduced for drying the condensate-containing meal and $ accordingly is shared. The air is pressed into the shot through the perforated bottom by a fan and - loaded with moisture - discharged to the side above the shot bed. Finally, the grist is cooled on the lower level, with a fan drawing cold air through the grit through a simple perforated floor.

From a constructional point of view, this "toaster dryer cooler", or TTK for short, is a single device, but in terms of process technology it is a matter of intermeshing. the result of three working stages, because a different treatment of the shot takes place on each floor.

The TTK is of particular economic advantage due to its low investment costs, since three otherwise independent processes can be carried out with independent systems in a single container.

In addition, the vertical sequence of work processes means that conveyor elements such as conveyors, elevators, screw conveyors, etc. are saved.

The consumption of energy (steam, hot air, cooling air) is also significantly lower than with a system consisting of three separately operating systems, e.g. an isolated varnish, a connected fluid bed dryer and a tube cooler or the like.

On the other hand, it has been shown that, in particular with very large-scale TTKs, such as those e.g. are used in the de-benzinating of petrol-soybean meal, the consumption of electrical energy is higher than in known classic de-benzinating plants with cascade coolers, tube bundle dryers, etc.

In particular, the consumption of electrical energy at the TTK is essentially determined by the power of the main shaft, on which stirring arms are attached for each floor of the multi-day system, which move through the shot in order to convey it evenly over the floors and the formation of to prevent the inflowing gases (water vapor, hot air, cooling air) from forming channels.

In this context, operational studies have shown that the main load and thus the largest amount of electrical energy is to be found in the area of gasoline removal, that is to say for the movement of the petrol-based scrap, but not in the drying and cooling sectors. It is understandable that the wet shot containing up to 30% and more hexane offers greater resistance to the stirring elements than the only water-moist or the already dried material. Of course, the fans for hot and cold air movement also require electrical energy, but this consumption has no relation to the drive shaft of the stirring elements in the area of the actual de-benzinization.

In order to reduce the energy consumption on the main stirring shaft of the TTK, in a further training of the same the gasoline sector itself was provided with further floors and with it also floors as well as stirring arms moving over these floors. In addition, the ratio of height to diameter was improved in favor of the building, i.e. longer apparatuses were constructed which were smaller in diameter. This made it possible to install the floors in the de-benzene stage, which can always be found at the top.

Such a desolventizer toaster (DT), which also goes back to the development work of the inventor, is described in EP-A-0 070 496.

In this device, for gasoline-soybean meal, the steam is used as direct steam at the lowest point, i.e. introduced below the bottom floor of a multi-day system and distributed over perforations. This device is also provided with a central shaft, by means of which the stirring arms are moved little above each perforated floor. The individual floors can in turn be designed as raised floors, which have a large number of specially designed perforations through which a so-called spray effect is achieved. This makes it possible to guide the steam blown into the lowest area of the vertical device from floor to floor on its way upwards without hindrance and thereby practically preclude the formation of steam channels.

By this relatively simple design measure, that is, by sharing the Entbenzinierungszone in several, in particular three to four floors, each with a stirring member, but which are all driven by a common shaft, and by the presence of a plurality of specifically designed _e r Dampfdurchtrittslochungen in the Multi-level floors, in particular double floors, could be achieved that despite the increase in the number of stirring elements in the demineralization stage and despite the longer path of the steam on its way from the bottom to the top, the power requirement on the stirring shaft by 30 to 50%, with unchanged system capacity, was reduced.

Of particular importance is the fact that this device has a solvent (hexane) / water vapor vapor temperature of 66 to 68 ° C allows without any loss of the degree of petrol treatment, ie residual solvent content in the shot and general economic efficiency of the system.

Because this reduction in the temperature of the vapors from hexane and steam emerging from the petroleum spirit from the usual 72 to 78 ° C or above to 66 to 68 ° C and partly below has the consequence that the consumption of direct steam for expelling the hexane from e.g. 160 to 170 kg per 1000 kg of hexane-soybean meal (approx. 20% hexane content) at over 72 ° C to a little over 150 kg per 1000 kg of meal at 66 ° C. For today's large-scale industrial plants, a significant cost reduction, e.g. if Several thousand tons of soybean meal must be burned in short intervals.

It is assumed that, in particular, the channeling of the steam in the previously customary de-benzene stages without any intermediate shelves is responsible for the higher steam requirement, because this additional steam escapes from the system directly through the vapor connection piece without being used.

Despite perfect functioning activity it was this semiconscious einetagig working Entbenzinierern, even with TTK to work is not always possible under economically completely satisfactory conditions (steam consumption, high Hexanaustreibung, time economic process flow, etc.), even with _Tem p _era - temperatures of 70 ° C and higher in the brothers ..

It has been shown that even at such low vapor temperatures, residual hexane contents of 0.05 and more, and in some cases even up to over 1.0%, were found in the demineralized shot after a short start-up period. Such high hexane However, contents make the meal unusable for nutritional reasons.

It was therefore again forced to switch to conventional vapor temperatures of over 72 ° C.

Due to the installation of several additive trays in the demineralization stage according to EP-A-0 070 496, the upward vapor is continuously redistributed from intermediate tray to intermediate tray, so that the latter is fully used practically without the formation of ineffective flow channels. In addition, the condensation of water vapor in the shot drops considerably.

Further economic improvements result from a new development by the inventor, which is described in European patent application 82 106 498.7 (publication number 0 077 436). Overheated steam from temperatures up to 215 ° C is used. The steam condensation in the grist is reduced again, which not only results in reduced water vapor but also results in a grist that is less wet.

This in turn leads to a noticeable relief of the subsequent drying unit.

Steam consumption is a decisive criterion for assessing economically managed de-benzinating. Then there are the consumption figures for drive energy for the stirring elements on the floors and - albeit subordinate - for the fans for hot and cooling air procurement.

The moisture content (water content) of the shot increases in the course of the demining, whereby, by the transfer of evaporation heat on the hexane the water vapor condenses itself. For example, the water content during the descent of hexane-soybean meal increases in the final phase of the descent according to a typical evaporative-condensation process close to the factory from approx. 12% by weight to approx. 22 to 23% by weight when it is received in the descent. On the other hand, in the case of soybeans, for optimum hexane expulsion, a water content of more than 17% by weight in the demineralized meal is desirable, since this is the only way to reduce the hexane content to a minimum and to ensure the desired nutritional value of the meal.

This relatively high water content in the demineralized meal is naturally offset by an increased energy expenditure during drying. This energy expenditure can e.g. for hot air, the efficiency of the gasoline and thus the entire oil production system may be called into question.

It is therefore an object of the invention to show a way by which an optimal solvent expulsion (gasoline removal) from the shot is achieved with a simultaneous reduction in the amount of condensed water which is to be expelled again in a downstream drying installation due to high energy expenditure.

According to the invention, this object is achieved _in that the actual de-benzination with water vapor is preceded by a so-called pre-de-benzination with indirect steam or another indirect form of energy transferring heat in a continuous system equipped with several stages or floors.

It is true that in the case of pre-petrol treatment with indirect heat transfer when steam is used, such are required, as mentioned, other forms of energy such as electr. Energy possible however, the condensate of indirect heat transfer by steam is obtained as free water, which no longer has to be steamed out of the meal. In addition, the pre-petrol treatment relieves the actual de-petrol treatment with direct steam - which cannot be completely dispensed with for procedural and product-quality reasons - while further reducing the energy required to drive the stirrer shaft in the petroleum spirit (TTK, DT, etc.) and allowing either to reduce the size of the drying and cooling units that follow the gasoline removal, or to combine them into a single unit.

The latter is of the utmost importance, especially in large systems, since e.g. With annual capacities of 1 million tonnes of shot, such throughputs can no longer be managed in a single, direct-steam-operated gasoline-free system (TTK or DT). With the help of pre-petrolization, in particular through indirect steam, existing petrol generators are not only relieved, there is now nothing standing in the way of operating technical and economic units that can handle even greater capacities than the previously stated limit of 1 million tons of scrap annually. Indirect heat transfer to the shot in pre-gasoline is of crucial importance, which takes place without condensation of water vapor in the shot.

As a special result of such a measure, the overall improved energy yield is also to be assessed, which has an effect, for example, in an average saving of 50 kg and more steam for the demining process per 1000 kg of processed seed (soy).

Although, as already mentioned, other indirect heat exchangers can also be used in the pre-gasoline, indirect steam is preferred because it does not require any additional supply devices because it is readily available in an oil production plant.

Steam-heated screws, trough conveyors with stirring elements, paddle screws, tumble and tumble dryers, etc., which are suitable for continuous operation and have, of course, to be equipped with the necessary extraction and condensation devices for the expelled solvent have proven to be suitable pre-petroleum spirits. Working in a vacuum can also be an advantage.

The amount of solvent to be expelled during the pre-petrol treatment, especially with indirect steam heating, e.g. Hexane from soybean meal is on average between 20 and 70%, in particular between 40 and 60%, preferably 50% of the solvent present in the wet meal.

Values of this kind can be easily achieved with well-managed pre-gasoline. Complete solvent expulsion through indirect heat transfer, i.e. that is, without subsequent de-benzing by e.g. direct water vapor is not advisable due to the quality of the shot.

The pre-gasoline not only saves energy, especially water vapor, it can also combine the drying and cooling process, thereby significantly reducing the size of the equipment. This is e.g. in principle possible when using a petroleum spirit as described in EP-A-0 070 496 and which goes back to the TTK according to "Fette-Soap-Paints" (1.c.). It is also advantageous to use superheated steam in accordance with European patent application .82 106 498.7.

Simultaneous drying and cooling can e.g. can be achieved in that the cooling air (primary air) is led directly through the demineralized but still warm meal, while the exhaust air from the cooling system via a heat exchanger converts the cold fresh air for drying (secondary air) to the required temperature without significant additional effort for heating the secondary air e.g. 55 ° C and above. This warm secondary air is blown in above the scrap bed, which is initially still wet with water, which is moved in the combined drying and cooling unit. It dries the material and then combines with the cooling air, which is also heated by the cooling process

Since the secondary air requires considerably less energy (only electrical energy for driving a fan) and the amount of primary air is reduced by the circulation of the secondary air, not only is less electrical energy required overall, but the apparatus pool is also reduced by combining dry air - and cooling level, it reduces the performance and the design of the blower and finally the above measures also shorten the time of the shot throughput, ie the overall capacity of a plant can be increased.

• Es zeigen: Fig.1 als Blockschema eine bisher übliche Entbenzinierungsanlage ohne die erfindungsgemäße Uorentbenzinierung;
• Fig.2 den Aufbau einer Entbenzinierung unter Einschluß der erfindungsgemäßen Vorentbenzinierung;
• Fig.3 die Anlage nach Fig.2, jedoch mit der zusätzlichen, ebenfalls erfindungsgemäßen Kombination von Trocken- und Kühlstufen Gemäß Figur 1 wird in einem Extrakteur (1) beliebiger Bauart das Ausgangsmaterial (5), z.B. Sojaflocken, mit dem Lösemittel (6), z.B. Hexan, im Gegenstrom behandelt. Die Konstruktion und Arbeitsweise des Extrakteurs spielt im Rahmen der Erfindung keine entscheidende Rolle, d.h. es können alle kontinuierlich arbeitenden Extrakteure, insbes. solche mit Gegenstromfahrweise, verwendet werden. Einschlägige Extrakteure sind allgemein bekannt, sodaß auf deren Nennung hier verzichtet werden kann.

The invention is subsequently explained by way of example with reference to FIGS. 1 to 3.

• 1 shows, as a block diagram, a previously customary gasoline installation without the gasoline gasoline according to the invention;
• 2 shows the structure of a gasoline treatment including the pre-gasoline treatment according to the invention;
• 3 shows the system according to FIG. 2, but with the additional combination of drying and cooling stages, also according to the invention According to FIG. 1, the starting material (5), for example soy flakes, is treated with the solvent (6), for example hexane, in countercurrent in an extractor (1) of any type. The design and mode of operation of the extractor does not play a decisive role in the context of the invention, ie all continuously working extractors, in particular those with a countercurrent mode of operation, can be used. Relevant extractors are generally known, so that they can be omitted here.

The so-called Miscella (8), which contains approx. 20 to 40% oil (remainder solvent and water), is continuously withdrawn from the extractor (1) and fed to the processing (distillation, oil refining, possibly further solvent distillation, etc.)

The hexane-wet soybean meal - used here as an example for the overall process - passes from the extractor (1) via line (15) to the gasoline (2), which is generally in direct connection with the scrap drying (3) and the shot cooling (4) without these three stages of shot processing must form a single unit.

The gasoline in (2) is carried out with the help of water vapor, which according to the latest knowledge is preferably fed in at the bottom of the gasifier (2), which operates frequently continuously, via line (7). Here, the ne in EP-A-0070496 described b _e Entbenzinierer has proven particularly useful. This consists of a predominantly cylindrical container with several levels, which are provided with sieve or perforated plates with discharge elements (locks) as floors that close at the bottom. Stirring elements are provided on a common shaft for each floor. that keep the shot in constant motion. This enters the device above the top floor and arrives by gravity below, to be redirected via a lock into the drying and cooling zones.

During this movement process of the shot, this steam is directed towards it from the lowest floor, whereby the steam is constantly redistributed due to a particularly advantageous construction of the intermediate floors, so that any channel formation is excluded and optimal de-benzinating takes place. During this process, as mentioned, part of the steam condenses, thus moistening the shot.

It should be mentioned here that after a further development of the petroleum spirit, described in the European patent application 82 106 498.7, superheated direct steam results in a particularly high energy saving in the petroleum spirit.

As shown in Fig. 1, the vaporizer vapors consisting of water vapor and hexane vapor are also processed, i.e. Separation of the water from the hexane and possibly distillation of the latter before it is returned to the extraction.

For the sake of order, it should still be noted that the petroleum spirit known as "TTK", with the combination of petroleum spirit, drying and cooling in a single container, has also found its way into the market.

Regardless of the type of petroleum spirit (2), the hexane-free but condensate-enriched meal is largely freed of water in the drying stage (3) - with the help of warm or hot air - and then cooled to ambient temperature in (4) with cold air. Via (10), the hexane-free, dry and cooled grist can be used again.

According to FIG. 2, the actual de-benzinating (2) is preceded by a pre-de-gasing (12). This leads to the fact that up to 70%, possibly even more, of the hexane contained in the hexane wet shot is expelled. In contrast to the actual or main de-benzination, the pre-gasoline works with indirect heat transfer, especially with indirect steam, which means that the water content in the shot does not increase.

Nothing changes in the extraction system (1,5,6,8,15). The pre-gasoline is directly connected to the transport route between the extractor (1) and the gasifier (2) and can, for example, accomplish the transport through line (15) as a steam-heated screw. The solvent expelled in the pre-benzine (12), in the special case hexane, is fed to the solvent preparation via (14), as are the vapors (9) escaping from the gasoline.

It is also advantageous to use a main petrol engine (2) which is constructed on the basis of the device according to EP-A-0 070 496 or European patent application 82 106 498.7.

From the actual de-benzinization (2) with direct steam (7), the water-containing scrap reaches the drying and cooling stages, which either act as isolated units (3, 4) according to Fig. 1, or as a combined drying and cooling stage (11 ) are connected downstream of the mineral spirits (2).

'Jon is of particular importance in this case a further development according to the invention, in which the combined drying and cooling unit (11) is directly connected to the petroleum spirit as a uniform structural whole.

Such a system and its operational structure is shown in FIG. 3. Shown in the block diagram is a system which, according to the invention, contains a pre-gasoline, and is equipped with a combined drying and cooling unit, which in turn forms a unit with the actual or main-gasoline, so that drying and cooling take place in one work step.

The hexane-wet good coming from the extraction (not shown), for example: Soybean meal (100) with approx. 25 to 35% hexane is heated to the evaporation temperature of the hexane in the pre-gasoline (120), whereby between 58 and 62% of the hexane evaporate during the passage of the shot through the pre-gasifier. This is continuously discharged -GG _f .u _n t _he a weak vacuum and fed via (140) of the preparation.

The warm shot, which still contains about 10 to 15% of hexane, flows from the pre-tinder (120) via line (122) in a continuous flow into the actual or main-teller denoted overall by (200).

It can be an advantage if the entire route (122) acts as a pre-gasoline. If possible, this section (122) should also be insulated and, if necessary, indirectly heated in such a way that the grist essentially maintains the temperature at the outlet from the pre-tinder until it enters the main de-tanner (200).

The example of the main de-benzinator with direct steam admission (200) shown by way of example and only schematically in FIG. 3 comprises three de-benzinating stages (a, b, c) with retracted perforated plates designed as raised floors, the floors being able to be fed with both indirect and direct steam .

On a common central shaft (only indicated as the center line of the container (200)), stirring arms move slightly above each floor, as a result of which the shot is constantly moved and circulated.

Direct steam, in particular superheated steam (107), is blown in below the bottom floor of the main de-benzinization, i.e. below the floor (201) forming the end of stage (c), and as it passes through floor (201) over the entire cross-sectional area of the main Entbenzierers (200) evenly distributed.

The steam flows through all floors or stages (c, b, a) and de-petrifies the shot. As a result of the evaporation of the hexane, part of the injected water vapor condenses, while the rest of the water vapor with the hexane leaves the gasoline vapors via (100).

Suitable gasoline units for main gasoline and fully continuous operation are described in EP-A-0 070 496 and in European patent application 82 106 498.7, the European patent application 82 106-498.7 in particular relates to a gasoline unit for direct, superheated steam .

_.% Enriched hot shot continuously _- via a lock (104) in the bottom floor (201) of the actual debenzining the now hexanfreie, but with water up to 22 to 23 wt .-%, in operation only to 15 to 19 weight reached into the combination of drying and cooling according to the invention (stage d). This unit is similar, if not identical, to stages (a, b, c), which means that stirring elements are also effective here abut the common central shaft and be moved over raised floors that correspond to those of steps (a, b, c). At least, however, the base (202) is designed as a perforated base, so that the cooling medium introduced via connection piece (2C3) is uniformly distributed over the entire cross section of the base.

For the combined drying and cooling in only one process step (d), cold air (primary air) is first blown in via line (150) from the blower (151) through support bracket (203) into the room (204) under the distributor floor (202) and through the Soil (202) on the warm, but already largely dried grist moved in (d). The grist cools down and passes through a further lock (105) in the bottom (202) via line (110) for final processing or recycling.

The primary air warmed when passing through the warm, largely dry grist in (d) leaves the system via line (141), passes a cyclone (140) or a similar device for separating dust and grit particles and reaches an average temperature of 45 to 65 ° C, in particular 50 to 60 ° C, over the heat exchanger (130) Freihe (135).

In the heat exchanger (130), the heated primary air gives off most of its heat input to new fresh air (131), which heats up as secondary air to about 44 to 64 ° C, in particular 50 to 60 ° C. The secondary air heated in this way passes via line (132) and fan (133) and line (134) into the space above the scrap bed in stage (d).

Here, warm primary air and warm secondary air combine and have a drying effect on the wet shot falling down via lock (104) into step (d).

The combined air flows escape via line (141), cyclone or dust separator (140) etc. and, after their heat content has been released in the exchanger (130) to fresh secondary air (131), emerge from the system via (135).

At the same time, the dry and cooled grist leaves the plant via (110) in a chemical and physical state, which it z.2. can be used directly for most feed.

It goes without saying that the process that can be derived from FIG. 3 or the system shown schematically in FIG. 3 can only be evaluated as an example for the scope of the invention and its technical applicability.

This applies above all to the design of the devices, their interaction, the general operating conditions such as dwell times, air circulation, etc. Also, all the elements shown, such as cyclones, dust separators, heat exchangers, fans, etc., must be adapted to the respective optimal conditions.

The measures of the invention not only optimize the energy consumption figures for the de-benzination of solvent-wet extraction residues - a particular consequence of the pre-de-benzination according to the invention - the scope of the apparatus can also be reduced by the main de-benzination + combined drying and cooling that occurs as a unit. It has been shown, for example, that the condensate of the indirect steam that arises in the prebenting as feed water of the steam boiler contributes to its relief, that the path between the extractor and the denaturing by using an indirectly steam-heated screw conveyor or an equivalent conveyor unit makes the investments for the prebenting practically balances, since this way in everyone must be covered.

The pre-petrol treatment can also reduce the effort for solvent preparation from the main de-petrol treatment, since the solvent obtained in the pre-petrol Hexane, no separation of water is required.

Finally, the throughput and thus the capacity and performance of gasoline plants, which already experience a serious increase through pre-gasoline alone, are further optimized by the combined drying and cooling.

Claims (12)

1. A process for the de-benzinization of residues that occur in the extraction of vegetable, oil and fat-containing raw materials with organic solvents after separation of the miscella containing the oils and fats, the solvent-containing residues in particular in countercurrent in continuous operation from bottom to top flowing de-benzinants, preferably water vapor, are exposed and sink under their own gravity from top to bottom and are de-gasified, and the vapors formed from the de-benzine and the solvent are continuously withdrawn, while at the same time the condensed de-benzene-containing but now essentially solvent-free residue material the lower area of the counter-current gasoline is withdrawn and fed to a drying and cooling. characterized in that the actual de-benzinating is preceded by a pre-de-benzing by direct action of the de-benzing agent, which takes place by indirect heat transfer. That the Vorentbenzinierung lschnecken in an indirectly heated with steam and is provided with venting means for being exaggerated solvent transport means such as screw conveyors, PADD _e or other, wicking action and furnished for the evaporation of the solvent apparatus takes place 2. The method according to claim 1, characterized. 3. The method according to claims 1 or 2, characterized in that in the pre-gasoline by indirect energy transfer between 20 and 70%, in particular between 40 and 60%, on average around 50% of the solvent present in the extraction residue is driven out. 4. The method according to claim 3, characterized in that the extraction residue consists of hexane-soybean meal. 5. The method according to claim 3, characterized in that water vapor is used in the actual gasoline as the gasoline. 6. The method according to claim 5, characterized in that the water vapor is overheated. 7. The method according to claims 1-6, characterized in that a device according to EP-A-0 070 496 or 0 077 436 is used for the actual de-benzinization. 8. The method according to claim 7, characterized in that the actual debenzination drying and cooling stages are combined into one unit. 9. The method according to claim 8, characterized in that the combined drying and cooling stage form an apparatus unit with the actual gasoline removal. 10. A process for the de-burning of hexane-soybean meal, the one containing between 20 and 40% by weight of hexane, from the extraction of soy flakes with hexane as a solvent Coming grist in a unit consisting of several treatment floors, with a common stirrer shaft and one stirring unit per floor and each floor closing off the perforated floor, is fed directly from top to bottom, the vapors consisting of excess steam and hexane steam continuously on the head be withdrawn from the plant and the water-moist grist fed to a subsequent drying and cooling stage by condensed steam, characterized in that the hexane-wet grist coming from the extractor is prebentified up to 70% in an early-stage gasifier with the aid of indirect steam heating, which is now based on hexane depleted meal of the actual de-benzination described above is supplied with Direlt steam and is de-gasified to the end here. . A method according to claim 10, characterized in that the drying and cooling of the demineralized shot is carried out in a combined stage directly downstream of the actual demining with air circulated. 2. Device for carrying out the method according to claims 1-9 and 10 -11, consisting of the pre-petrol (120) between the extractor and the actual demister (200), a demister (200) according to EP-A-0 070 496 or 0 077 436, comprising the steps (a, b, c ...) for the actual debenzining and an output stage (d) for the combined drying and Küh-, _lun g wherein the Vorentbenzinierung is formed (120) as heated with indirect steam transport device and occupies at least part of the way between the extractor and the actual de-benzinization (200), the air for cooling the shot dried in the combined drying and cooling stage (d) via a blower (151) into the space (204) below the bottom perforated floor (202 ), above the dried scrap bed in (d) mixed with preheated dry air from (134) and the combined air flows via line (141), dust separator (140) and heat exchanger (130) are used to heat fresh air (131).

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