DE2941571C2 - Process for hydrolytic starch digestion - Google Patents

Description

The | -rfimliin *. ' refers .nil a process / around hydrolviisi her · \ n (inferred to strong in t eUlfriichten> o painted the (uiiuiifrsbegnft dos! '. iicnunsprin. ms '

Such a discontinuous process for the hydrolytic digestion of starch is used in factories. The predominant alcoholic beverages are made from grain, potatoes or roots (there are also continuously decreasing strengths. .i 'have preserved Dem d.ts discontinuous pressure · ■■ ·) dämpfvcrlahren offers the following advantages:

a) Security and completeness of the digestion of the Starch up to dextrins;

b) speed of operations ·;

c) in damaged areas, odorous substances, the rinse the product, namely the alcohol, (rähtigen wtirclefiihiif steam be blown out?

d) Distilleries that work in connection with agriculture can be carried out in batches Better adapt operations to the availability of labor and the required throughput and

e) It can be unmilled mash material, such as grain. Roots, potatoes, etc. in the steamer be given, since the starch is gelatinized and liquefied by the action of heat and then by blowing out the mash material with a pressure difference of about 2 to 5 bar is torn that a complete liquefaction and saccharification by enzymes subsequently is possible.

On the other hand, there are two disadvantages of the discontinuous pressure damping process.

On the one hand, there is a disadvantage in the increased heat requirement, because the pressure damping process is included Temperatures from about 145 to lb5 ° C.

On the other hand, exposure to excessively high temperatures and / or exceeding a certain temperature occur Heating time, harmful condensation reactions, which, in addition to hydrolysis, caramel substances and Let melanoidins arise, which leads to reduced yield and impaired taste. While the rate of hydrolytic breakdown of starch without enzyme action in increasing the Reaction temperature is approximately doubled by 10 ° C, the aforementioned harmful reactions mainly set in at higher temperatures, they become with increasing temperatures accelerated and probably promoted autocatalytically, which is why the Flydrying process by increasing the temperature does not can accelerate at will.

For the aforementioned reasons, the known Pressurized steam process grumls.it/lich in the following stages executed:

1. Fs an amount of water preheated as far as possible by waste heat is put into the steamer, which has about 2.0 to 3.2 times the weight of the mash material. (This amount of water is shown in the following as the quantity of fresh water.) Together with the condensation water entering the mixture during steaming, this results in a hydrolysis system. Namltch gelatinized starch, which after further hydrolysis and possibly further addition of water with yeast can be fermented quickly / in aqueous solutions with 8 to 10% alcohol
According to de: Pro / cl.iw, ute quantity, the either comminuted or preferably iin / reduced-sized M.i.iUTial. like / tin. Example the grain given in the steam. Dn I \ is Dampt introduced into the D.itnpfer and displaces the air from the steamer at K) OC If then tiin the Abliiftlei ^ iles steamer closes increase pressure "no Lemper, NIIR his on reaching the Pro / eHlem by, iliir the steam supply is closed
When the process temperature and pressure have been reached, the casualty follows, during which the water splits the large particles into pieces, producing paste, dextrins, and, to a lesser extent, various sugars; But condensation processes are already emerging. Reactions of this kind take place very quickly at low temperatures, which is why this operating phase is

tricky. Therefore, the mash material must be cooled down immediately when the Stäike is completely gelatinized will. This is done by blowing it out (relaxation evaporation).

The above illustration shows that the simplicity, safety and effectiveness of the pressure-damping process are offset by the high heat consumption as a particular disadvantage, which is particularly important in view of the necessary energy savings. Therefore, it has already been proposed by the applicants to reduce the heat losses of the pressure damping process by heat recovery, see DE-PS 29 33 661. In the present case, it is particularly important that the heat requirement for <. , the hydrolysis process is primarily dependent on the amount of process water required based on the weight of the mash material.

The invention is therefore based on the object, in a method of the generic type, the .'n Reduce heat input / u by reducing the for the Hydrolysis of the starch at high temperature, the amount of process water used is so limited that

1. Nevertheless, those for the gelatinization reactions.>; required amount of water is available and

2. the hydrolyzate becomes so fluid that it can still be transported in pipelines.

III

The solution to this problem arises in practice as follows «.nig on the other hand:

Maischgui from, for example, the same weight of mix material and process water at a temperature of 80 to 100 "C is Z ^- next so π liquid that it can be pumped or stirred, when the temperature rises to the eating temperature it suddenly becomes gelatinous be as tough and lumpy that neither is possible by the pulse inflowing steam nor kraftiges, mechanical * a MOORISH stirring, to the extent this is possible. one even remotely getting even distribution of further necessarily supplied heat to the entire Maischgut. Consequently, Spatial areas of the mash material are exposed to high temperatures beyond what is necessary for liquefaction and are burned, while the other spatial areas of the mash material, which are thus limited, are not sufficiently opened up because sufficient temperatures cannot be applied to them long enough (Quality as well as bet serious operational disruptions as a result. that the improperly gelatinized and liquefied masses clog pipes and fittings -, 5

With the known methods one has this evilMciix! so far it.iJurch counteracted that the corn mating,)! ·> Ι \; an ample amount of water you c..i> JO up to 3.2 times the weight of the mash material h.) l. 'inpcr'Mixed with a high amount of steam. It is therefore a further aim of the invention, in spite of the reduced amount of process water, to avoid the disadvantages mentioned, in particular due to clumping of the mash material, as well as the partial excess or lack of heating that this causes.

The object underlying the animal invention is now solved by the characterizing features of claim 1.

The particular advantage of the invention is that the pressurized process water met their Pressure is on the order of 3 to 13 bar, so is quickly introduced into the bulk of the field crops in the hydrolysis vessel that instantly a strong Turbulence and mixing of the mash material and the corresponding mash material occurs and all Particles of the mash are heated evenly to the desired temperature of 135 to 170 "C before a clear gelatinization occurs.

In principle, it is known to produce a starch slurry in the case of continuous saccharification of starch Send through a heat exchanger under turbulence in order to convert this viscous liquid into a To heat the hot.iogenic phase quickly, compare CH-PS 4 73 895. There, however, it is important to use the continuous operation in vertically arranged reaction tubes and the heat exchanger the formation to avoid a phase that is heterogeneous in terms of viscosity and density by cooling the Ruhrwändc. For overcoming the particular difficulties encountered in the discontinuous pressure steaming process, there is known procedures no indications.

In the method according to the invention, the fruits are also advantageously dry or largely dry Entered dry into the hydrolysis vessel. This mixed material is preferably not crushed into the empty hydrolysis vessel poured out. The temperature of the Process water amount can be in the order of 190 ° C and higher, so that it depends on the Proportion of the amount of process water based on the mash material weight can be dispensed with, for example by supplying steam to compensate for a lack of heat If steam is added to the mash it is advantageous to use the steam in this way Also blow in the hydrolysis gel quickly. in order to also the amount of heat supplied by the steam Sich Distributed as evenly as possible under the mix. the Process water quantity and the Dan-pf needed to deci.ng a missing amount of heat at the same time or together introduced into the hydrolysis vessel will

A device is useful for carrying out the new process. The peculiarity of this is that a water pressure vessel connected to it via at least one feed line is arranged next to the hydrolysis vessel. Its release capacity is at least the amount of process water required for water spraying. Advantageously, the cash capacity of the water pressure vessel is greater than the volume of the process water required for a job * c ^r il · η k.inn Ks can store excess water or Dampfnienge in the pressurized water tank, so that in addition required D.nip 'trelcite via a line from the vapor space of the water Dniikbehal ters in the Hvdmlvscgefätt' then at the same time h or nathcinanile ¹ V., ivser and steam from the water pressure vessel ιι> ln FlvdroU setJcfaU transferred «.erden

So that in the pressure vessel at Ubcrlciiun ^ dcb water, or the steam from the water pressure vessel a stirring effect is achieved, advantageously form the mouths of the connection lines in the hydrolysis vessel one or more jet nozzles, which are on or in the mash pipe are directed.

in detail the process according to the invention runs using the above device such as

following tab:

The preferably uncrushed mash material is poured into the empty hydrolysis vessel, a pressure damper. Except for a small vent opening, the pressure damper is then closed. The water at high temperature and under the appropriate pressure is then allowed to flow into the bulk of the mash material in the pressure damper so quickly that the entire content of the damper, i.e. the mash material, is strongly swirled and the amount of process water is entered into the damper in a short time. The temperature of the introduced amount of process water is suitably in the order of 190 ⁰ C, with the pressure depending on the capacity of the water pressure container and the pressure damper of the order of 3 to 13. bar. The amount of process water is only 0.8 to 1.0 times the weight of the mash material and is therefore only about half the amount of water that is used in conventional processes. Corresponding to the proportion of the reduced amount of process water, the amount of heat to be used for the hydrolysis process is also reduced.

It is of particular importance that r he amount of process water must be completely introduced into the pressure damper in a few minutes. The one with the hydrolysis process Connected gelatinization of the mash does not start suddenly, which is why the can still mix the heated amount of process water with the mash material. This is done by Jetting the amount of process water into the mash material achieves a stirring effect. This creates a a largely uniform temperature distribution in the mash, without the result of Verkleiste.ung Form lumps over the entire mash material, which are only heated unevenly can. Based on our experience, it has proven to be advantageous if the time for the Inserting the total amount of process water and steam required in the order of 2 to 12 minutes per batch.

Scho with the process amount of water or immediately thereafter, if necessary, the introduced to achieve the required Maischguttemperatur in the order of 135 ° to 170 ⁰ C required quantity of steam. This amount of steam must also be introduced before the mixture begins to clump together.

Since both the amount of process water and the steam that may be required further with a high pressure difference and consequently high speed can be introduced into the pressure steam generator, there arises a higher Turbulence and agitation effect than can be achieved with a mechanical agitator. at suitable design of the damper and the water or The introduction of steam can therefore be an energy-consuming one Agitator can be dispensed with entirely.

By the measures mentioned it is achieved that after the time required for the gelatinization Mash becomes so liquid again in its entirety that it can and also flow through pipes is equally open-minded.

As already stated above, a suitable device for carrying out the method according to the invention has, in addition to the pressure damper, an additional pressure vessel in which the water required for at least one batch can be provided and, if necessary, heated by introducing steam to the extent required for the method. This pressure vessel is connected to the Hyjrolysegefäß via a line and Absperrvorrichtungeii so that the overflowing water can swirl the mashing material in the damper strongly, which one C ¹ Urch can achieve a tangential or deep-mounted connector on the hydrolysis vessel or by means of a groove formed as a jet pipe mouth. Another advantage of the separate water pressure vessel is that the process water can be heated over a period of about 4 to 6 times as long as compared to conventional methods and devices in which the process water is heated in the hydrolysis vessel itself. This enables a reduction in the power peak of the steam boiler system and thus an improvement in efficiency and a reduction in investment costs. This saving far outweighs the cost of the additional pressurized water tank.

When the pressure vessel is dimensioned so that it contains more hot water than required for a batch the amount of steam for any remaining heating of the can from its steam space The mash can be removed quickly via a specially attached steam line. The device then allows a completely constant load on the supplying steam boiler system.

Claims (5)

Patent claims: 1. Process for the hydrolytic AufwhluB of starch in crops by pressure heating individual batches in a hydrolysis vessel, in which a heated amount of process water and the fruit are entered as mash, this mash is brought to a process temperature of about 135 to 170 C under appropriate pressure and during a dwell time dependent on the temperature reached is subjected to the hydrolysis process and the amount of water used is 0.8 to 1.6 times the weight of the fruit and is brought to a temperature of approximately the process temperature under pressure, characterized in that first the fruits are entered into the hydrolysis vessel and then the pressurized process water quantity is introduced into the hydrolysis vessel with swirling of the fruits in such a short time that the gelatinization of the mash associated with the hydrolysis process has not yet started or has only started insignificantly. 2. The method according to claim 1, characterized in that that the fruits are put into the hydrolysis vessel dry or largely> 5 dry. 3. The method according to claim 1 or 2, characterized in that the temperature of the process water quantity is higher than the process temperature. 4. The method according to claim 3, characterized in that the temperature of the amount of process water is about! 90 ° C. 5. The method according to any one of claims 1 to 4, characterized in that to cover a missing amount of heat steam into the hydrolysis vessel with swirling of the mash within the time is blown in with the Hydrolysis process associated gelatinization of the mash not yet or only insignificantly has used. *O b. Method according to claim 5, characterized in that that the steam together with the quantity of fresh water in there. Hydrolysis vessel initiated will