GB2185174A

GB2185174A - Treating straw with ammonia

Info

Publication number: GB2185174A
Application number: GB08600526A
Authority: GB
Inventors: Philip John Paxman; Lloyd Forster
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-01-10
Filing date: 1986-01-10
Publication date: 1987-07-15
Anticipated expiration: 2006-01-10
Also published as: GB2185174B; GB8600526D0

Abstract

A method of treating straw with ammonia comprises wrapping a bale of straw with a plastics film so as to provide an airtight cover around the straw. Within the bale there is placed a charge of a substance capable of producing ammonia when in contact with an activating medium, for example solid ammonium carbonate. When it is desired to initiate ammoniation, the activating medium, for example water is introduced into the sealed bale, for example by a hosepipe inserted through a small aperture made in the film, after which the aperture may be sealed by adhesive tape. The water reacts with the ammonium carbonate to produce ammonia gas which ammoniates the straw.

Description

SPECIFICATION Treating Straw with Ammonia Field of the Invention This invention relates to the treatment of straw and whole cereal crop forage with ammonia.

Background to the invention Straw hasa high gross calorific value and although this energy is derived from carbohydrates the metabolisable or useful energy available to a ruminant animal is relatively low. This is because the carbohydrate in straw has a low digestibility as a consequence of the highly lignified nature of the cell walls ofthe straw. The lignification effectively protects the carbohydrate energy within the cells from the digestive processes in the rumen and in the lower gut of the animal. The essence of ammonia treatment of straw is that the ammonia attacks and breaks down the lignin content of the cell walls, greatly increasing the availability of the carbohydrate energy to the ruminant's digestive process.Within the rumen the microflora are able to utilise the unlocked energy and by the digestive process of rumination this becomes available to the animal.

The basic problems associated with the ammoniation of straw are the high cost and the large scale of the operation, together with the toxic hazard of handling raw ammonia. In practice, ammoniation of straw is carried out by professional contract teams who visit the farms with expensive ammonia tankers and specialist personnel. The cost involved in supplying such a service requires that the operation be carried out on a relatively large scale and it is normal practice to ammoniate a minimum of 20 to 40 tonnes of straw. The invention aims to provide a simpler and cheaper method of ammoniating straw.

Summary of the Invention A method of treating straw or whole cereal crop forage with ammonia comprises wrapping the straw or forage with a plastics film which provides an airtight cover around the straw or forage, incorporating in the wrapped straw or forage a substance which produces ammonia when brought into contact with an activating medium, and subsequently introducing the activating medium into the wrapped straw or forage to cause the production of ammonia within the cover.

The straw or forage may be in bales, eg large round bales, and wrapping of the bales may be achieved by wrapping the plastics film round each bale as the latter is simultaneously rotated about its horizontal and vertical axes, as disclosed in UK Patent Specification No 21 59489A. The ammonia producing substance is incorporated in the wrapped bale and provides a latent source of ammonia which may be activated at will by the application of the activating medium.

The ammonia producing substance is preferably a solid, such as ammonium carbonate which has the advantage of being an easily handled powder, nontoxic and readily activated by the simpler technique of the application of water which consitutesthe activating medium. The water may be introduced into the wrapped straw or forage by means of a hosepipe inserted through a small aperture made in the film, the aperture then being sealed by the application of sticky tape or the like to maintain the airtight enclosure of the cover.The water can either be applied shortly after the wrapped straw or forage has been transported from the fields to the place of storage, thereby taking advantage of the warmer ambient temperatures in the summer which will increase the speed of the ammoniation process, or the farmer can store the wrapped bale for any required period and then initiate the ammoniation by the introduction of water.

According to another aspect of the invention there is provided apparatus for treating straw or whole cereal crop forage with ammonia, comprising wrapping means for wrapping the straw or forage with plastics film so that the latter provides an airtight cover around the straw or forage, a substance which is incorporated in the wrapped straw or forage and which produces ammonia when brought into contact with an activating medium, and said activating medium which is subsequently introduced into the wrapped straw or forage to cause the production of ammonia within the cover.

Description of Preferred Method As an example of the invention, a method of treating straw bales with ammonia will now be described with reference to the accompanying flowchart.

Straw is first formed into large round bales by conventional baling machines, as indicated at 1.

Each large round bale is then wrapped with plastics film in the manner disclosed in UK Patent Specification No 21 59489A. The plastics film is fed to the bale whilst the latter is simultaneously rotated about is horizontal and vertical axes. The plastics film tightly encircles the bale and provides an airtight cover around the bale. Prior to wrapping, a charge of ammonium carbonate is incorporated in the bale, the amount of ammonium carbonate being chosen so that the resulting ammonia will be sufficient to treat the straw in the bale. This is shown at 2 in the accompanying drawing.

The resulting bale thus has a tightly encircling air impervious cover with the ammonium carbonate therein. The ammonium carbonate can be activated at any chosen time by the simple expedient of making a small hole in the cover, inserting a hosepipe into the hole and injecting an appropriate volume of water into the straw. This is shown at 3.

The aperture in the cover is then sealed by means of adhesive tape, as shown at 4.

The water reacts with the ammonium carbonate to produce ammonia gas. The ammonia gas is retained by the enveloping cover and acts on the straw to break down the lignin content by the known process. Ammonium carbonate produces approximately one third of its weight of ammonium gas when reacted with water.

The advantages of incorporating the ammonia before wrapping are those of reducing handling, facilitating transportation, minimising the complexity of introducing either a dry powdered substance of a toxic, noxious ammonia solution or gas at a later stage. The treated ammoniated straw has a high dry matter content and is transportable at relatively low cost.

Claims

1. A method of treating straw or whole cereal crop forage with ammonia, comprising wrapping the straw orforage with a plastics film which provides an airtight cover around the straw or forage, incorporating in the wrapped straw or forage a substance which produces ammonia when brought into contact with an activating medium, and subsequently introducing the activating medium into the wrapped straw or forage to cause the production of ammonia within the cover.

2. A method according to Claim 1, wherein the straw or forage is in bales and wrapping of the bales is achieved by wrapping the plastics film round each bale as the latter is simultaneously about its horizontal and vertical axes.

3. A method according to claim 1 or 2, wherein the ammonia producing substance is solid.

4. A method according to Claim 3, wherein the ammonia producing substance is ammonium carbonate.

5. A method according to any of the preceding claims, wherein the activating medium is water.

6. A method according to claim 5, wherein the water is introduced into the wrapped straw or forage by means of a hosepipe inserted through a small aperture made in the film, the aperture then being sealed by the application of adhesive tape or the like to maintain the airtight enclosure of the cover.

7. A method according to claim 5 or 6, wherein the water is introduced shortly after the wrapped straw or forage has been transported from the fields to the place of storage, thereby taking advantage of the warmer ambient temperatures in the summer which will increase the speed of the ammoniation process.

8. A method according to claim 5 or 6, wherein the wrapped bale is stored for a required period and then ammoniation is initiated by the introduction of water.

9. Apparatus for treating straw or whole cereal crop forage with ammonia, comprising wrapping means for wrapping the straw or forage with plastics film so that the latter provides an airtight cover around the straw or forage, a substance which is incorporated in the wrapped straw or forage and which produces ammonia when brought into contact with an activating medium, and said activating medium which is subsequently introduced into the wrapped straw or forage to cause the production of ammonia within the cover.

10. A method of or apparatus for treating straw and whole cereal crop forage with ammonia, substantially as herein particularly described.