GB2176386A - Method and apparatus for treating plant material - Google Patents

Abstract

A method and apparatus for making animal feedstuff comprising germinated grain comprises mixing the grain with a water absorbent polymeric material, such as a cross-linked acrylamide polymer, and water and employing the polymer as a source of water for germination of the grain. Preferably, grain and polymer are soaked in water before mixing. The grain and polymer mixture is formed into a layer on a conveyor having perforations to admit air to the layer of plant material. Germination conditions are maintained on the conveyor. The conveyor is driven continuously or stepwise to provide a suitable residence time e.g. 4 days for the plant material to form into a mat. The mat is discharged continuously or batchwise at an unloading station, cut up, and fed directly to animals such as cattle.

Description

SPECIFICATION Method and apparatus for treating plant material This invention relates to a method and apparatus for treating plant material. In particular, but not exclusively, the invention relates to a method and apparatus for germinating seeds. A particular example of such method relates to the germination of grain to produce animal feed, but the invention is by no means restricted thereto, and is also applicable to the germination of other seeds and may also be of benefit in relation to the treatment or growth of other plant or crop material.

It has been known for a long time that animals benefit from eating grain that has been previously dampened and permitted to germinate and to sprout. Such feed is more easily digestible and is rich in vitamins and thus constitutes a valuable feedstuff. In orderto effect such germination and sprouting it is necessary to supply to the seeds not only water, but also oxygen and the necessary temperature.

During the 1960s, proposals were made for apparatus to produce germinated grain as an animal feedstuff, but the apparatus required a great deal of supervision and handling and thus although the test results with the animals fed with the produced feedstuff were outstanding, the system was handicapped by the complexities of the productionsystem. Subsequent proposals involving the use of air conditioned containers in which environmental factors such as light, temperature, ambient humidity and water supply were controlled, were handicapped in a similar way. The investment to produce the product was inevitably large and qualified persons were required to supervise the operation of the sytem.

We have thus identified a need for improvements in relation to the method and apparatus for germinating grain, and indeed other seeds and plant material, offering improvements in relation to matters discussed above, or generally.

According to a first aspect of the invention there is provided a method of treating plant material comprising providing the plant material on conveyor means in a layer, providing ambient conditions to enable growth of the plant material, driving the conveyor continuously or intermittently to provide a residence time forthe crop material thereon, sufficient for the treatment or growth process concerned, and unloading the treated or grown plant material continuously or batchwise at an unloading station, and loading the conveyor with further quantities of the plant material continuously or batchwise at a loading station.

Preferably, the conveyor means comprises a support surface for the plant material formed with perforations. The perforations are preferably small enough to prevent escape of a majority of the plant material conveyed thereon. In the case of the germination of grain, the perforations formed in the conveyor surface are preferably just small enough to prevent significant quantities of ungerminated grain falling through the perforations.

According to a second aspect of the present invention there is provided a method of treating plant material comprising providing a perforated support for the plant material, forming a layer of plant material thereon, the thickness of the layer being up to 2 centimetres, and preferably at least 15 centimetres, providing the conditions to permit plant growth or plant treatment as required, and removing the plant material from said support after treatment or growth.

Preferably, the plant material is mixed with a particulate extender. Said extender preferabiy comprises a water absorbent/releasant material.

According to a third aspect of the present invention there is provided a method of treating plant material comprising providing a quantity of plant material, mixing same with a particulate water absorbent polymeric material of the kind defined herein, forming a layer of the mixture on a support therefor, and providing said layer with the conditions for plant growth or treatment while such growth or treatment proceeds.

The invention also provides apparatus for treatment of plant material comprising conveyor means. The conveyor means comprises a support surface for the plant material. The support surface is preferably formed with perforations. The support surface may be arranged to be driven intermittently or continuously. The rate of drive of the support surface may be such that the residence time of the plant material is such that the plant material can be treated or can effect the necessary growth stage during its residence time. The conveyor means may be provided with an unloading station and a loading station for the plant material. Ambient condition control means may be provided, suitably positioned in relation to the conveying run of said conveyor means. The ambient condition control means may comprise heating means.

The invention also provides a method and apparatus for treatment of plant material comprising any novel feature or step or novel combination of features or steps disclosed herein.

In an embodiment described below there is provided a method and apparatus providing means forthe production of animal feed, but which can also have application to other materials and processes. In the embodiment, the production of the feed takes four days, the depth of the growing grain bed is variable up to a very considerable depth, and the materials moves forward on the conveyor continuously. On the first day of the process a grain and water supply medium are formed into a layer on the belt of the conveyor, and each day the belt moves forward by one quarter of the length of the conveying run thereof. On the fourth day, the processed animal feed is discharged.

In the embodiment, the conveyor arrangement is such that it can be readily extended to suit particular requirements and does not require an irrigation system. The particulate water absorbent material (described and defined below) which is mixed with the grain provides a readily available reserve of humidity which supplies to the grain exactly the correct amount of water which it requires, thereby promoting regular growth and germination and thereby also substantially reducing the time required for germination and sprouting. Moreover, supervision of the process is eliminated, or virtually so.

As regards the animal feedstuff produced by the embodiment, the digestibility of cereals by animals is always incomplete, and it is for this reason that they are often treated before their consumption, by rolling or indeed pre-cooking, the latter totally destroying the vitamins of the feed. The low digestibility of cereals feeds hitherto has been due to a great extent to the large molecular size of the material of the feed, such large molecules being assimilated only with difficulty. As a result, such feedstuffs are not perfectly crushed during chewing by the animal, and the attack by digestive juices is slow and incomplete. The feedstuff produced by the embodiment of the invention provides advantages arising from the presence of essential amino-acids.

The accumulated proteins normally found in cereal grains areforthe most part made up of amino-acids that contain nothing to help the build up of animal tissue. The method ofthe invention brings about their transformation into basic amino-acids such as Lysine. A further advantage lies in the high enzyme content of the feed material which when released into the digestive tract of the animal assists in the digestion of other feed ingredients. This increased assimilation by the animal has resulted in a 40% increase in the digestible value of the feed. For example, the daily addition of the feedstuff to the diet of a horse results in no oat grains being found in the animal's droppings.

In this specification the term water adsorbent polymer and like expressions are to be interpreted in the light of the following. Firstly, the example of such material used in the described embodiment is available under the reference PR3005Afrom Messrs.

SNF Floerger of 41 Rue Jean Huss, 42000 St.

Etienne, France, underthe name "Aquasorb" (trade mark). This material is a synthetic water retention aid proposed for use in the reclamation of desert and other dry soils. It comprises a synthetic polymer understood to be polyacrylamide. It is understood that polyacrylate polymers may also provide similar properties. The properties relevantforthe present invention are the ability to absorb water in considerable quantities. For example, the PR3005A material is capable of adsorbing 500 litres of distilled water per kilogram of the dry polymer. In this specification, at the time of initial filing thereof, no significance is to be attached to the distinction between the two terms adsorption and absorption.

We have found that water exchange between the polymer and crop material is reversible, the amount of exchange depending on the conditions of use.

Particle size of the polymer in the dry state is preferably about 2 to 3 millimetres. The term water absorbent particulate material is thus to be interpreted as covering materials such as the Aquasorb PR3005A described above and similar materials capable of reversibly exchanging water forthe purpose of plant growth.

An embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which: Fig. 1 shows a side elevation view of one end of conveyor means forming apparatus for performing the method of the invention; Fig. 2 shows a similar side elevation view of the other end of the conveyor means; Fig. 3 shows a section through the conveyor of Fig. 2 on the lines Ill-Ill; Fig. 4 shows a plan view of part of the conveyor of Figs. 1 to 3; and Fig. 5 shows, on a larger scale, a detail of the conveyor of Fig. 4.

As shown in the drawings, a conveyor 10 comprises upright supports 12 forming a framework carrying conveyor units 14 and 16, which are of substantially identical construction and therefore only conveyor unit 14 will be described in detail.

Conveyor unit 14 comprises a conveyor belt comprising modules to be described in detail below and trained around end rollers 20, 21 in an upper conveying run 22 and a lower return run 24.

At the input end of the conveyor, a series of heating units 26 are provided below conveying run 18 to raise the plant material placed thereon to the optimum temperature for germination and sprouting. Below the heater units is provided a drain tray 28 to collect any liquid passing through the conveyor.

At the other end of the conveyor shown in Fig. 2 there is provided below conveying run 18 a seris of washing elements 30 providing jet spray nozzles to spray the return run 24 of the conveyor before it is re-used. A drip tray 32 is provided to catch the water therefrom.

As shown in Fig. 3, the conveyor 18 comprises modular conveying elements 34 to be described in more detail below. Fig. 2 also shows the growing germinating crop material 36 carried on conveying run 22 of the conveyor. Corresponding parts of conveyor unit 16 are not numbered in these drawings since they correspond exactly with those of conveyor unit 14.

At the side edges of conveyor unit 14 are provided retaining walls or guides 38 to define the side edges of the conveying zone for the crop material.

Crop material is placed on the conveyor at a loading station 40, and is discharged therefrom at an unloading station 42.

As shown in Fig. 5 the conveyor 18 comprises belt modules 44 linked in head-to-tail fashion by rods 46 inserted through castellated hinge type connectors provided on the modules. Perforations 48 are provided in the modules to permit drainage and access and escape of gases.

In this embodiment the modules are of the type M8A formed of plastic material and available from Messrs. Cooper Handling of Heath Town, Wolverhampton, England. The width of the conveyors in this embodiment may be from 45.7 centimetres to 121.9 centimetres. The conveyor apparatus may be provided with one, two (as shown), or three or four conveyor tiers.

In use, the apparatus described above is employed as follows.

In a preliminary stage, the pre-treatment of the grain and water adsorbent polymer is as follows.

In the case of the grain, 330 kilograms of grain is placed in a pre-treatment vessel having a water inlet and a screened water outlet with associated control valves. 480 litres of water are provided in the vessel and the grain is left to soak for a minimum of 8 hours, after which the outlet valve is opened and all water allowed to drain off.

In a similar treatment vessel, from 4 to 7 kilograms of the dry particulate polymer material reference PR3005A described above is added to 680 litres of water and left for a minimum of two hours.

After this, the resultant crystalline water-containing gel is mixed with the pre-soaked grain produced as described above and the mixture is then discharged onto the conveyors 14 and 16 described above. The layers of crop material thus produced may vary according to choice. In this embodiment, the provision of the germination conditions decribed enables greatly thicker layers to be used than has ever been possible in germination processes before, it is thought. Thus, for example, crop material layer thicknesses up to 15 centimetres and more can be employed according to operating requirements.

The temperature for the pre-soaking of the grain may be up to 20 degrees centigrade. For the pretreatment of the polymeric material, the temperature may be up to 45 degrees centigrade.

This latter process results in considerable expansion of the particles of the polymer.

The conveyors 14 and 16 are driven intermittently or continuously while the necessary growth conditions of temperature and air supply are maintained. The time taken to reach discharge station 42 is four days. The process is operated continuously. Daily discharge of crop material is followed by daily re-loading at the station 40.

The animal feed material discharged at station 42 comprises germinated and sprouted grain in a coherent mass that can be readily cut from the remainder for discharge. It can be fed directto cattle and other animals. The presence of the polymer in the feed is quite harmless to the animals.

Many modifications could be made in the abovedescribed method and apparatus while remaining within the scope of the invention, these including the use of alternative conveyor designs, including a spiral or other non-linear conveyor arrangement.

Likewise, other seeds and other crop material may be treated by the method of the invention, and alternative polymeric water adsorbent materials may well become available in due course and are to be included as relevant materials for the purpose of the invention.

In a further embodiment, not illustrated, modified provision is made for pretreatment of the grain and polymeric material prior to deposition on the conveyor.

Apparatus for pretreatment of the grain and polymer comprises a polygonal-section mixing drum into which is placed the mixture of grain and polymer, together with a suitable quantity of water, as described above. The drum is very slowly rotated for a period of two to three days for example.

In this way, the mixture of the grain and polymer is effectively accomplished and water absorption by the polymer is likewise accomplished effectively, and the need to effectively mix damp grain and the somewhat homogeneous polymer (after take-up of water) is avoided.

The temperature within the drum is controlled and perforations formed in the drum permit discharge of any gas resulting from anaerobic processes during the formative hours.

One panel of the drum is removable for direct discharge of the pretreated mixture onto the flat bed conveyor. After this, the process proceeds as described above.

With respect to the polymeric material, it is to be understood that the term "polymeric material" is employed in the claims of this applications means a polymer capable (in its dry state) of absorbing significantly more than its own volume of water and of making water available, after such absorption, for use by plant material. In the above description we have already identified the preferred material employed in the above embodiments. By way of further identifications of the nature of the material, we add to this disclosure that the polymeric material may be an acrylamide suitably cross-linked. For example, it may be cross-linked with methylene bisacrylamide. Such material may be made by polymerising acrylamide with tetramethylenediamine in the presence of N,N' methylene bisacrylamide as cross-linking agent.The polymer so produced absorbs water in the quantities identified above to produce a gelatinous mass which makes the water available for plant growth/ treatment and germination.

From the foregoing it will be understood that our discovery that the above polymeric material can be used as a growing medium or plant treatment material in itself in amounts of up to 100% of the medium (as measured by weight and ignoring the weight of any water absorbed in the polymer at the time of weighing) amounts to a significant step forward in the art. By use of this discovery the germination of grain and other seeds, and the corresponding treatment of plant material is greatly facilitated. The simple mixing of seed material with the polymer and treatment of water, after which the water requirements of the plant material are supplied by the polymer represents a great simplification of previous techniques and permits the production of feedstuffs in the manner already described.

Moreover, our discovery that the polymeric material can be employed as part of the feedstuff for animals without harmful effects means that the resulting mat material can be directly used for feeding to cattle or other animals without any complications which would otherwise arise. It might be possible to remove the polymeric material by suitable treatment whereby only the germinated seeds were left. In such a condition, the material might even be acceptable for human consumption.

In this latter case, it will be understood that seed materials other than grain would naturally be of significance, such as certain types of beans and the like.

Further modifications envisaged include the use of the techniques described above for biological growth of other plants and organisms using the convenience of the techniques evolved for feedstuff production as described above.

Afurthermodification envisaged includes the use of a scraper conveyor as the conveyor means of the invention in which suitable crop material pushing elements or bars are moved over a support surface carrying the crop material. The support surface could likewise be formed with perforations or vents and would function in a very similar way to that described above.

Claims (26)

1. Afeedstuff comprising germinating seeds mixed with a polymeric material as defined herein.

2. A feedstuff according to- claim 1 in the form of an animal feedstuff.

3. A feedstuff according to claim 1 or claim 2 comprising less than 10% by weight of materials other than said seeds, said polymer and water.

4. Afeedstuff according to any one of the preceding claims in the form of a mat held together by sprouts or chits of said seeds.

5. A feedstuff according to claim 4 wherein the thickness of said mat, measured between its uppper and lower surfaces, lies in the range of 2 centimetres to 30 centimetres.

6. A feedstuff according to claim 5 wherein the thickness of said mat lies in the range of 5 centimetres to 20 centimetres.

7. A starting material for the production of a feedstuff comprising germinatable seeds mixed with a polymeric material as defined herein, said polymeric material being in a dry condition in which water for germination of said seeds is not available from it.

8. A method of making a starting material for the production of a feedstuff comprising mixing germinatable seeds with a polymeric material as defined herein.

9. A method of making a feedstuff comprising mixed seeds with a polymeric material as defined herein.

10. A method according to claim 9 wherein said seeds are mixed with said polymeric material in a dry condition of the latter, and the mixture is then treated with water.

11. A method according to claim 9 wherein said polymeric material is treated with water before mixing with said seeds.

12. A method according to claim 11 wherein said seeds are treated with water before mixing with the polymeric material.

13. A method according to claim 12 wherein said seeds are allowed to germinate, but not to sprout or chit significantly, before mixing with said polymeric material.

14. A method according to any one of claims 9 to 13 comprising the step of forming a layer of said mixture and providing conditions for plant growth for the seeds in said layer.

15. A method according to claim 14 wherein said layer is formed on conveyor means, said conditions for plant growth being maintained while said layer remains on the conveyor and growth or germination proceeds, the method further comprising the step of progressive discharge of germinated material at a discharge station.

16. A method according to claim 14 or claim 15 wherein the thickness of said layer, measured between its upper and lower surfaces is from 2 centimetres to 30 centimetres.

17. A method according to claim 16 wherein the thickness of said layer lies from 5 centimetres to 20 centimetres.

18. A method according to claim 15 wherein air supply means for said layer comprises vents or perforations formed in said conveyor means.

19. A feedstuff according to any one of claims 1 to 7 wherein the content of the feedstuff excluding seeds and water comprises said polymer in an amount from 50% to 100% by weight.

20. A plant treatment material comprising from 50% to 100% by weight of a polymeric material as defined herein.

21. A method of treating plant material comprising providing a quantity of plant material, for example germinatable seeds, mixing said plant material with a plant treatment material according to claim 20, forming a layer of the mixture on a supporttherefor, and providing said layer with the conditions for plant growth or treatment while such growth or treatment proceeds.

22. A method of treating plant material comprising providing a perforated supportforthe plant material, forming a layer of plant material thereon, the thickness of the layer lying in the range from 2 centimetres to 30 centimetres, providing the conditions to permit plant growth, germination or treatment as required, and removing the plant material from said support after treatment, germination or growth.

23. A method according to claim 22 wherein the thickness of said layer lies from 5 centimetres to 20 centimetres.

24. Apparatus for performing the method of claim 22 or claim 23 comprising conveyor means having a support surface for the plant material, the support surface being formed with perforations or vents.

25. A method of treating plant material comprising providing the plant material on conveyor means in a layer, providing ambient conditions to enable growth of the plant material, driving the conveyor continuously or intermittently to provide a residence time for the plant material thereon sufficient for the treatment or growth process concerned, and unloading the treated or grown material continuously or batchwise at an unloading station, and loading the conveyor with further quantities of the plant material continuously or batchwise at a loading station.

26. Apparatus for performing a method of treating plant material, substantially as decribed herein with reference to and as illustrated in the accompanying drawings.