FR2478953A1 - Animal feed from abattoir, dairy, preserving floating sludge - by submitting acid sludge to decantation, then mixing with nitrogenous substrate and premixes to give liquid or solid feeds - Google Patents

Abstract

Process for the production of animal feeds from mineral and organic by product floating sludges, suspended in agricultural- food industry effluents (esp. from abattoirs, preserving plants and dairies) and having pH 1.8-7, by submitting the floating sludges recovered from the effluents to at least one decantation, such that the dry material content of the decanted sludge is 8-12%; then mixing the decanted sludge with sufficient quantity of a substrate having a suitable dry material content so that the resulting food mixture has a dry material content of 25-50% and optionally adding other food compounds to give a feed material suitable for animals. Preparation of animal feeds from organic/mineral by-products recovered from abattoir, preserving-plant and dairy effluents by flotation.

Description

PROCESS FOR PRODUCING ANIMAL FOODS FROM
FLOATED SLUDGE AND CORRUPTANT FOOD.

 It is known that the effluents discharged by agri-food industries such as dairies, canning factories and slaughterhouses are heavily loaded with organic and mineral matter and it has therefore been sought for a long time to eliminate or reduce the pollution of the plant. water used by this kind of industry by the installation of treatment plants. In order to facilitate the work of the purification plants, the organic effluents which are to be removed from them are removed from the liquid effluents which are to be removed. This elimination is carried out by the so-called "floatation" technique which may consist, for example injecting air into the effluent in order to bring the suspended solids back to the surface, and these floating materials are, in a conventional manner, assisted by a surface scraper and poured into a pit.

 The so-recovered organic materials generally referred to as "floated sludge" are rich in pro teats and, therefore, may be desirable for use in animal feed. However, feed is most often in the form of pellets or flours, that is, dry products with a low water content. Float sludge has an extremely low solids content Consequently, it is necessary to resort to a thermal dehydration of a prohibitive cost, making the use of this source of nitrogenous matter in the animal feed uninteresting.Therefore, it has never been envisaged until now to use the Float sludge from agro-food effluents in animal feed otherwise than in solid form.

 It is also known, although it is not very common, to use so-called liquid foods, that is to say those with a high water content. But precisely because of their high humidity, the kind of liquid food poses conservation problems as a result of the microbial development that can take place, while it is slowed down or prevented in the case of solid foods (in the form of granules or flours) that contain a small amount of water. The microbial development is of course dependent on the total number of germs contained in the initial liquid feed. Float sludge presents a very high level of contamination in this respect, especially in terms of total germs (mesophilic flora) in anaerobiosis (clostridium sulpho-reducers) and in aerobiosis (coliforms). In addition, it sometimes happens that the floated sludge contain pathogenic germs including salmonella, staphylococcus, brucella and tuberculous bacteria. Therefore, if it is envisaged to introduce floating sludge into the composition of liquid feeds, there is a double obstacle: it is imperative to destroy in the floated sludge the bacterial flora and, this necessary but not sufficient condition being filled, it is also necessary to prevent bacterial growth during storage in a favorable environment, because of the high humidity of the liquid feed; in addition, the liquid feed must have good physical and chemical stability over time making it suitable for prolonged storage.

 Thus, despite their high nitrogen content, the floated sludge has not been used until now in animal feed: indeed, or the floated sludge is part of the composition of solid foods but in which case the thermal dehydration that the cost price of the food obtained must be struck and made prohibitive; Float sludge is used in the composition of liquid feeds, but it is essential to solve the double problem of the effective destruction of bacterial flora in floated sludge, which is generally highly contaminated, and bacterial development during storage. liquid food.

 The present invention aims to provide a method of manufacturing a liquid or solid food for animals, to overcome the aforementioned drawbacks. With regard to the preparation of a solid food whose dryness can reach 80-95E, the process according to the invention provides for increasing the dry matter concentration of the floated sludge essentially by mixing with a dry cellulosic substrate, dehydration thermal intervention only to increase the dryness of the food from 25-45 to about 702.

 With regard to the preparation of a liquid food whose dryness is in the range of 40-50x, the process according to the invention makes it possible in particular to effectively destroy the microbial flora of the floated sludge and the production of a medium. which not only benefits from good physical and chemical stability over time, but also prevents subsequent microbial growth during storage, despite its high water content.

 The subject of the present invention is therefore a process for producing feedstuffs from floating sludges derived from organic and inorganic materials suspended in the effluents of the agro-food industries, such as effluents from slaughterhouses, canning factories or dairies. , the pH of the floated sludge being between about 1.8 and about 7, characterized in that the sludge recovered from the effluents is subjected to at least one settling so that the solids content of the settled sludge is included between about 8 and about 12%; that the sludge is mixed with a substrate taken in an amount and a solids content such that the resulting feed mixture has a solids content of between about 25 and about 50 (the above percentages being expressed as weight relative to the weight of the sludge or slurry) and that other food components are also added to the sludge in order to obtain a qullibrd feed for animals.

 In the present invention, the recovery of floated sludge from effluents from slaughterhouses, canneries or dairies or any other food industry is done by known techniques, in particular by adro-flotation or electro-flotation. . The supernatant organic and inorganic materials are then entrained by a surface scraper and inverted into a storage tank.

 the pH of the floated sludge recovered is generally between about 1.8 and about 7. However, depending on the physico-chemical process used in the recovery of the floated sludge, the latter may have either a very acidic pH between about 1.8 and about 2.5 or a weakly acidic pH between about 6 and about 7. According to the invention there are two modes of implementation, one for preparing food from Flotation sludge strongly acidic, the other aimed at preparing food from flotation sludge weakememnt acids.

Each of the two embodiments above is broken down into two particular embodiments according to whether it is desired to obtain a solid food having a dryness of 88 to 95 or a liquid food whose solids content is in the range of from 40 to 50.

 In a first embodiment, the floated sludge recovered has a weakly acid pH of between 6 and 7. For the manufacture of a liquid feed for animals, such as poultry, cattle, pigs and sheep, the following treatment is provided: the floated sludge recovered for a period of time of between 2 and 24 hours is subjected to a first settling; a first acidification of the floated sludge from the first settling with a strong mineral acid is carried out; then, a second decantation is carried out for a period of time of between half an hour and 2 hours, then the decanted product is mixed with a nitrogenous substrate and at least one premix, so as to obtain a mixture suitable for feeding animals ; and finally, a second acidification of the mixture is carried out by a strong mineral acid, the acidified mixture being optionally stored for use in animal feed.

 Advantageously, the floated sludge is, prior to the first settling, treated with hydrogen peroxide in case of a high bacteriological contamination.

 Both settling operations are carried out conventionally inside tanks, preferably in stainless steel. The recovery of the settled product can be carried out in two different ways: either the decanted product is withdrawn from the bottom of the tank while the supernatant liquid is removed; or the pumping liquid is removed by supernatant leaving, therefore, the decanted product at the bottom of the tank. The settling time depends essentially on the type of initial float.

In both successive acidifications, the strong concentrated acid is preferably commercially available sulfuric acid, which normality is about 10 N. The sulfuric acid used must be free of heavy metals so that the food manufactured and treated with such an acid is compatible with the food legislation in force. In the first acidification, the proportions of acid that is added to the sludge from the first settling are between 0.5 and 27. by volume relative to the total volume of sludge decanted. The first acidification makes it possible to lower the initial pH of the sludge which, in this first embodiment, is generally between 6 and 7 up to a value of approximately 4. If it is desired to lower the pH to even lower values and,
If it is desired at the same time to prevent the growth of sulphite-reducing germs in anaerobiosis, a mixture of iodine and phosphoric acid in proportions ranging from 8.5 to 2% (by volume relative to to the total volume of sludge) Such a mixture of iodine and phosphoric acid is commercially available, for example, under the designation "acidic acid."

 The first acidification of the settled sludge with or without treatment with a mixture of phosphoric acid and iodine is advantageously completed by a bubbling steam treatment whose duration may range from a few minutes to 2 hours depending on the volumes to be treated. and the concentration of sludge decanted. It is preferred, by this steam sparge, to bring the temperature of settled sludge having undergone a first acidification to a value close to 70 C. The acid will, due to the rise in temperature> act to the maximum of its efficiency and the pH of sludge can be further lowered by steam bubbling due to the homogenization that results.

 Therefore, if the pH after the first acidification is about 4, this value can be further lowered to about 3.8 by steam sparging to bring the sludge temperature to about 70 ° C.

 The combined action of acidification and steam treatment makes it possible to effectively attack and reduce the microbial flora (total germs) and especially the clostridium sulphito-reducers which are the most thermo-resistant especially in the spore form. It may also be noted that the rise in temperature resulting from the steam sparging has the effect of promoting the subsequent settling of the sludge.

 In the first implementation of the process according to the invention, the steam treatment is not an indispensable step: in the case where the latter proved to be too expensive, the sludge can be settled only acidification which is then performed with a larger amount of acid to compensate for the suppression of steam sparging.

 Once the pH of the sludge after the first acidification and optionally after the treatment with a mixture of iodine and phosphorus acid and steam bubbling, is stabilized at a value close to 4, the second de cation is carried out during a period ranging from about half an hour to about two hours, depending on the nature of the eight streams of departure.

 This settling time can be carried out in the same manner as the first one. Anoter decantation is improved with steam bubbling due to protein flocculation.

 Then, in this first implementation, the mixture of sludge from this second decantation, a nitrogenous substrate and at least one premix known type. The nature of the nitrogenous substrate and of the premix which is mixed with the sludge resulting from the second settling depends, on the one hand, on the composition of the original floating sludge and, on the other hand, on the final composition of the food that one wishes to obtain. However, as a general rule, the nitrogenous substrate is advantageously rich in total nitrogenous matter and especially in digestible nitrogenous matter while the premix (s) contain (s) small but effective amounts of trace elements necessary for growth and life. animals, vitamins, stabilizers, preservatives and agents to give the food mixture the required appetability.

 The sludge recovered after the second settling has a very low solids content of about 8 to 12%. Therefore, in this first embodiment, the sludge from the second decantation is mixed with the nitrogenous substrate taken in an amount and with a dry matter content such that the food mixture obtained has a solids content of between 40 and 50% (these percentages being expressed by weight relative to the total weight of the food mixture). Thus, the solids concentration of sludge from the second decantation which is very low can be significantly increased following mixing with the nitrogenous substrate, to a value between 40 and 507. without resorting to expensive thermal dehydration It is preferred that the nitrogenous substrate used has a solids content greater than 60%.

 More specifically, the nitrogenous substrate which is mixed with the sludge from the second decantation contains from about 20 to about 30% of total nitrogenous matter (these percentages being expressed by weight relative to the total weight of the nitrogenous substrate) and a number of forage units of between 0.5 and 1 (these units being expressed relative to 1 kg of nitrogenous substrate). In the present description, the term "forage unit" (UF) refers to the quantity of nitritic material equivalent, from a food point of view, to 1 kg of barley. A nitrogenous substrate of the above type is commercially available under the designation 1, Agravit ™.

 Once the food mixture has been prepared, the second embodiment of the invention is followed by a second acidification with a concentrated mineral acid, preferably with 10 times normal sulfuric acid. food grade. The proportions of acid added during this second acidification depend both on the degree of bacterial contamination of the food mixture and the category of animals for which it is intended. Thus, it is preferred that the pH of the final feed be about 3.90 for cattle, about 4.50 for pigs and about 5.0 for poultry. The degree of bacterial contamination can be demonstrated by a conventional microbiological method. Depending on the degree of contamination, the proportions of acid added can be between 0.5 and 0.9%, the pH obtained then being close to 4.5 if no mixture (iodine-phosphoric acid) has been added following the first acidification; or between 0.9 and 1.57, the pH obtained then being close to 4 if no iodine-phosphoric acid mixture or close to 3.80 has been added if it has been added, the above percentages being expressed in volume of acid relative to the total volume of the food mixture.

 The sludge from the second settling mixture with the nitrogenous substrate and the premix (s) can take place in any tank, preferably in stainless steel, equipped with a paddle stirrer. The second acidification can be carried out during this mixing. Although the incorporation of the premix can be carried out in a single batch, by pouring the desired quantity inside the tank, at the level of the paddle stirrer, the best solution is to equip the tank a recycling circuit.

 Such a circuitoomporte a decirculaticn pump ct, just downstream of the latter, the pipe advantageously comprises an opening to 1'intereur which opens a worm used to feed the mixture premix ai dosing rate wanted. Cecircuitoom- takes a static stirrer that ensures homogenization after incorporation ration. It is also possible by blowing inside the stirring tank of a mixture of air and premix powder form. However, this method of incorporation of premix presents risks of bacteriological contamination by aerobic germs.

 In known manner, the recycling circuit may comprise a stirrer -static for homogenizing the mixture. Such an agitator is for example composed of a helical piece mounted to pivot about an axis; this agitator comes into motion under the action of the circulation of the liquid mixture and causes a vortex which makes it possible to stir the mixture; this can then be returned to the upper part of the stirring tank. The above system, can significantly reduce mixing times and promotes homogenization of the mixture.

 In order to obtain better results against the development of the microbial flora in the food mixture having undergone the second aeidification, the initial floated sludge is oxygenated before the first settling, then treated with a mixture of iodine and phosphoric acid. and acidified by 112504 before steam bubbling; they are then brought to a temperature of 750 ° C. by bubbling with steam and then subjected to a second acidification with H 2 SO 4, after mixing with the substrate and the (or) premix, in proportions by volume of about 1.2% of acid. .

The food mixture having undergone the second acidification constitutes a liquid food which may possibly be stored for commercialization. The liquid feed can be consumed as is by the animals or after being mixed with the. forage or silage. It is observed that the liquid food thus prepared presents at the same time
excellent chemical stability over time;
- good physical stability by reducing deposits after an extended stay corresponding to the storage of the liquid food before marketing.

In a first variant of the first embodiment of the invention, a solid food is prepared from the liquid feed defined above. More specifically, the food mixture obtained after the second acidification of which the solids content is between 40 and 50% is subjected to a thermal dehydration allowing its solids content to be raised to about 70%. Thermal dehydration is performed in a classic cooker of the type "MAD", "STROMME", "wECOL-EQUIP", etc.
It may be possible not to incorporate
of meat meal because of the already good value of the
elaborated liquid liment. In this case, the thermal dehydration is continued up to 83-85% solids.

In the dehydrated mixture, a flour of
meat, preferably in the proportions by weight of
50/50. The latter advantageously has the composition
next average
- humidity: 8%
- mineral substances: 3%
- crude protein materials: 58%
- fat: 25%
- digestible protein content: 58%
As the meat meal has a content of materials
between 90 and 95%, its mixture with the product dehydrated in the appropriate proportions makes it possible to obtain a solid food whose solids content is between 80 and 85%. be stored for commercialization. It is intended to be incorporated into rations or dietary formulas for animals such as cattle, sheep, pigs and poultry at a rate of 5 to 15% and preferably at a rate of 10%, these percentages being expressed by weight relative to the total weight of the food formula.

 In the first embodiment of the invention, it is also possible to prepare solid foods having a solids content of between about 80% and about 85% according to a second variant defined below: the recovered floated sludge whose pH is weakly acidic from about 6 to about 7 are treated according to the same above-described procedure for preparing liquid foods until the second settling.

 However, in this second variant, the sludge from the second settling, whose solids content is from about 8 to 12% and is preferably about 10, are mixed with a dry cellulosic substrate taken in one part. such that the resulting mixture has a solids content greater than 25% and preferably between 40 and 45%.

 As a strongly hydrophilic carbon substrate for use in the present invention, there may be mentioned, in particular, cereal issues, ground maize crushed stalks, soybean and groundnut cakes, and ground kernels.

 The mixture of sludge from the second settling with a cellulosic substrate is carried out in a conventional mixer used to enrich certain peats or loams in mineral fertilizers. It can be mentioned in particular the mixer marketed by the company called "ALVAN BLANCH". A device of this kind comprises a mixing chamber inside which moves a vane conveyor for stirring the cellulosic substrate. The addition of sludge from the second settling is done via an injector disposed within the mixing chamber. The mixing time varies between 10 and 30 minutes depending on the nature of the cellulosic substrate chosen and the mixed volume.

This mixing step allows
to increase the dry matter content of the product to a value greater than 25% and, preferably, between 40 and 45%
- To enrich the sludge from the second decantation into other food components.

 Of course, it must be ensured that the quantity of the cellulosic substrate supplied is compatible with the digestibility of the final solid food.

 Once the sludge from the second decantation has been mixed with the cellulosic substrate, the first variant above is used: the mixture is dehydrated in a conventional type of cooker to bring its dry matter content to a minimum. value of about 70. The dehydrated product obtained is mixed with meat meal preferably in the proportions by weight of 50/50. The meat meal used advantageously has the average composition stated above.The mixture (dehydrated product-meat meal) constitutes the solid food according to the invention which is intended to be incorporated in a feed formula for cattle, sheep, pigs and poultry at 5 to 15% by weight and preferably at 10; according to the composition of the various ingredients (these percentages being expressed relative to the weight of the food formula).

 In the second implementation of the process according to the invention, it is intended to manufacture either solid or liquid feeds from floated sludge whose pH is strongly acid and in particular between 1.8 and 2.5. It is also in this pH range that the precipitation of proteins is the highest; the floated sludge is obtained by a known technique of flotation for example of aero-flotation. In this second implementation, the initial flotation sludge can be first steam bubbled, especially if their degree of contamination requires. This steam bubbling is performed for a period of time sufficient to bring the temperature of the floated sludge up to about 700 C. It has the effect of favoring the subsequent settling at the same time as it allows a pasteurization of the sludge by the destruction of the pathogenic germs and a flocculation of the proteins. The sludge is then decanted, in a known manner, to obtain a solids content of between 8 and 12%.

 In this second implementation, the sludge can be subjected to two different treatments depending on whether one wishes to obtain a liquid food (first variant) or a solid food (second variant) In the first variant, one operates as in the preparation of food described above in the first embodiment following the second settling, the two acidification operations not being necessary since the starting sludge has a pH between 1.8 and 2 5.

Thus, the sludge decanted -as mentioned above-is directly mixed with a nitrogenous substrate and at least one premix, so as to obtain a suitable food mixture having a solids content of between 40 and 50%. As already mentioned, the nitrogenous substrate which is mixed with the settled sludge contains approximately 20 to approximately 30% of total nitrogenous matter and a number of forage units of between 095 and 1 (per g of nitrogenous substrate. As a nitrogenous substrate, mention may also be made, by way of example, of the product sold under the name "AGRAVIT." The composition of this product is given in Table I below.

The <or) premixes that are added together with the nitrogenous substrate to the settled sludge contain (s) small but effective amounts of trace elements necessary for the growth and life of animals, vitamins, stabilizing agents, preservatives and agents to give the food mixture the required palatability
The operating conditions, the material used, the nature and the proportions of the premix and the substrate are the same as those which were previously indicated in the first embodiment for the preparation of the liquid feed. The pH of the resulting food mixture is optionally adjusted according to the category of animals for which it is intended. Thus, the pH of the food mixture that constitutes the liquid feed should be about 3.90 if it is intended for cattle, about 4.50 if it is intended for pigs, and about 5 stil is destined for poultry.

 In the second variant of the second embodiment (in which it is desired to manufacture a solid food from starting sludge having a pH of between 1.8 and 2.5) it is expected to add to sludge an agent food grade alkalization so as to bring the pH of the settled sludge to a value close to 4. The alkalizing agent used is sodium hydroxide or food grade lime.The other stages of preparation of the These liquid feedstocks are those described previously in the first and second variants of the first embodiment: firstly, the settled sludge, whose pH has been adjusted, is mixed with a dry cellulosic substrate so that the the resulting mixture has a solids content of between 25 and 45%, preferably between 40 and 45%; secondly, the resulting food mixture is subjected to thermal dehydration in a conventional cooker so that the dehydrated product obtained has a solids content of about 70%; thirdly, the dehydrated product is mixed with meat meal, which mixture constitutes the solid food which is intended to be incorporated in proportions ranging from 5 to 1570 to a feed formula for animals.

 It should be emphasized that the cost price of solid or liquid foods according to the invention is very small because part of the nitrogenous matter they contain is derived from floating sludge, that is to say from industrial waste. recovered during the effluent treatment process and which until now were eliminated, and also because the heat treatment necessary for the manufacture of such foods is either non-existent or very reduced.

 To better understand the object of the present invention will be described below, by way of purely illustrative and non-limiting, three modes of implementation.

In the following Examples I and II relating to the preparation of liquid feedstocks, the initial floated sludge is derived from wastewater from industrial slaughterhouses; their initial pH is about 6-6.5; they are decanted for half an hour and immediately acidified with 0.9% 10 N sulfuric acid of food grade, as they are produced by the apparatus which flotation to avoid any fermentation. anadrobia (in volume relative to the total volume of sludge)

after this first acidification, a bubbling steam treatment is carried out for 2 hours to bring the temperature of the acidified sludge to about 70 ° C; once the pH is stabilized to a value of about 4, a second decantation is carried out for half an hour. After cooling, the product resulting from the second decantation is then mixed with the nitrogenous substrate and with the two following premixes.
- product known under the trade name of "gravit" (with physical characteristics similar to those of molasses) which is a substrate for the cultivation of baker's yeasts; such a product contains, per kg, 250g of total nitrogenous matter, 240g of digestible nitrogenous matter and 0.70 fodder units; its dry matter content is between 65 and 70. The exact composition of this product is given in Table T appended hereto.

 premix marketed under the designation "Agralix" (powder concentrate containing all the oligodents necessary for the growth and life of animals).

 premix marketed under the designation "Melurolix" (powdered concentrate providing vitamins, stabilizing agents, preservatives and agents for giving the liquid food the required appetability).

 The exact composition of the two aforementioned premixes is also given in Table I.

 During the preparation of the above mixture, a new acidification is carried out with food grade 10 N sulfuric acid in proportions by volume of 1.2% (relative to the total volume of the food mixture).

EXAMPLE 1
By carrying out the above procedure, a liquid food is prepared, the composition of which is defined in Table II, appended hereto.

The liquid food has the following composition (in elementary constituents)

<tb> Phosphorus <SEP> 0.10
<tb> Calcium <SEP> 0.50 <SEP>
<tb> Magnesium <SEP> 0.30
<tb> Sodium <SEP> 1
<tb> Sulfur <SEP> 0.40
<tb> Copper <SEP> 100 <SEP> ppm <SEP> (parts
<tb> Zinc <SEP> 650 <SEP> ppm <SEP> by <SEP> million)
<tb> Manganese <SEP> 500 <SEP> ppm
<tb> Iron <SEP> 200 <SEP> ppm
<tb> Iodine <SEP> 6
<tb> Cobalt <SEP> 2 <SEP>
<tb> Vitamin <SEP> A <SEP> 3,000,000 <SEP> UI <SEP> (for
<tb><SEP> 100kg)
<tb><SEP> D3 <SEP> 800,000 <SEP> UI <SEP> (units
<tb><SEP> internationals) <SEP>
<tb><SEP> E <SEP> 1,000 <SEP> UI
<tb> Betane <SEP> (hepatho <SEP> protector) <SEP> 5 <SEP> 7,
<Tb>
This liquid feed is intended for young animals or dairy cows consuming mixed basic rations (but + "Ray Grass": "Ray Grass" + Alfalfa).

EXAMPLE 2
By carrying out the above procedure, a liquid food is prepared, the composition of which is defined in the attached Table III.

 This second formulation is more particularly intended to be added to corn silage at a rate of 1 kg per day.

EXAMPLE 3 Preparation of a solid food intended to be
incorporated into two food formulas for
poultry one called "growth", the other
called "finishing".

The procedure of Examples 1 and 2 is repeated, but instead of mixing the sludge from the second decantation with the nitrogen substrate "Agravit" and with the two premixes "Agralix" and "Melurolix", they are mixed with a cellulose substrate consisting of a soybean meal known as "Brazil Soy 42". The mixture obtained has a solids content of between 40 and 45; the mixture is dehydrated in a cooker until a solids content of about 70% is reached; the dehydrated product is mixed with meat meal.The resulting mixture has the following composition

<tb> Dry <SEP> Materials <SEP> 82
<tb> Proteins <SEP> 44.2
<tb> Materials <SEP> fat <SEP> 18
<tb> Energy <SEP> metabolizable <SEP> 3 <SEP> OOOkcal / kg <SEP>
<tb> Lysine <SEP> 2
<tb> Methionine <SEP> + <SEP> Cystine <SEP> 0.9
<tb> Calcium <SEP> 0.1 <SEP>%
<tb> Phosphorus <SEP> available <SEP> 0.1 <SEP>%
<tb> Cellulose <SEP> 3
<tb> Materials <SEP> Minerals <SEP> 8
<Tb>
The solid food above is incorporated in proportions by weight of 10% in two poultry feed formulas, the composition of which is given below.

<Tb>

<SEP> FORMULA <SEP> FORMULA
<tb><SEP> INGREDIENTS <SEP> FOOD <SEP> ALIMENTARY
<tb><SEP> DE <SEP> GROWTH <SEP> FROM <SEP> FINISH
<tb> Mats <SEP> 51 <SEP>% <SEP> 56 <SEP>% <SEP>
<tb><SEP> Soybeans <SEP> 31.5 <SEP> 70 <SEP> 25 <SEP> 70 <SEP>
<tb><SEP> Materials <SEP> fat <SEP> 4 <SEP>% <SEP> 5.6 <SEP>%
<tb><SEP> Food <SEP> Solid <SEP> of
<tb><SEP> the invention <SEP> 10 <SEP>% <SEP> 10
<tb><SEP> Carbonate <SEP> 0.55 <SEP>% <SEP> 0.70 <SEP>%
<tb><SEP> Phosphate <SEP> 1.95 <SEP>% <SEP> 1.70 <SEP> 7th <SEP>
<tb><SEP> Methionine <SEP> 0.08 <SEP>% <SEP> 0.06 <SEP> 1 <SEP>
<tb> Premix <SEP> 1 <SEP> 7th <SEP> Z <SEP>
<Tb>
Both poultry growth and finishing formulas have the following elemental composition

<tb><SEP> FORMULA <SEP> FORMULA
<tb><SEP> FOOD <SEP> ALIMENTARY
<tb><SEP> DE <SEP> GROWTH <SEP> FROM <SEP> FINISH
<tb> Energy <SEP> metabolizable <SEP> 3095 <SEP> kcal / kg <SEP> 3210kcal / kg
<tb> Raw <SEP> Proteins <SEP> 24.3 <SEP> X <SEP> 21.6
<tb> Cellulose <SEP> 2,6 <SEP>% <SEP> 2,5
<tb> Materials <SEP> Fat <SEP> 8.2 <SEP>% <SEP> 8.9
<tb> Materials <SEP> Mineral <SEP> 6.5 <SEP>% <SEP> 6.3
<tb> Calcium <SEP> 0.91 <SEP>% <SEP> 0.87 <SEP> Z <SEP>
<tb> Phosphorus <SEP> available <SEP> 0.50 <SEP>% <SEP> 0.45 <SE> Z <SEP>
<tb> Lysine <SEP> 1.35 <SEP> Z <SEP> 1.15 <SEP> Z
<tb> Methionine <SEP> + <SEP> Cystine <SEP> 0.92 <SEP>% <SEP> 0.82 <SEP> Z
<Tb>
It is understood that the embodiments described above are in no way limiting and may give rise to any desirable modifications without departing from the scope of the present invention.

TABLE I

<tb><SEP> COMPOSITION <SEP>"AGRAVIT"<SEP>"MELUROLIX"<SEP>"AGRALIX"
<tb> Dry matter <SEP><SEP> 67 <SEP> - <SEP> 78% <SEP> 907th <SEP>
<tb> Proteins <SEP> Brutes <SEP> 23.5- <SEP> 27%
<tb> Materials <SEP> Minerals
<tb> the <SEP> 13 <SEP> - <SEP> 18
<tb> N <SEP> (ammoniacal) <SEP> 0.3 <SEP>%
<tb> Ca <SEP> 0.14 <SEP> 10
<tb> P <SEP> 0.09
<tb> Na <SEP> 2 <SEP> - <SEP> 3 <SEP>%
<tb> K <SEP> 2-3%
<tb> S <SEP> 0.6 <SEP> X <SEP> 0.40 <SEP>% <SEP> 0.21 <SE> Z <SEP>
<tb> Cu <SEP> - <SEP> 100 <SEP> ppm
<tb> Fe <SEP> 440 <SEP> ppm
<tb> Mg <SEP> 0.6 <SEP> 5 <SEP>
<tb> Mn <SEP> 440 <SEP> ppm <SEP> 960 <SEP> ppm
<tb> Zn <SEP> - <SEP> 2 <SEP> 100 <SEP> ppm
<tb> Co <SEP> 6.7 <SEP> ppm
<tb> I <SEP> - <SEP> 20 <SEP> ppm
<tb> Lysine <SEP> 0.05 <SEP> w <SEP> 0.15 <SEP>% <SEP>
<tb> Methionine <SEP> 0.07 <SEP> - <SEP> 0.15 <SEP><SEP> 7 <SEP>
<tb> + <SEP> Cystine
<tb> Vit <SEP> A <SEP> - <SEP> 9 <SEP> 000 <SEP> 000 <SEP> IU
<tb><SEP> D3 <SEP> - <SEP> 800 <SEP> 000 <SEP> IU
<tb><SEP> E <SEP> - <SEP> 000 <SEP> mg
<tb> pH <SEP> 5.9 <SEP> - <SEP> 6.4
<tb> TABLE II

<SEP> QUANTITY <SEP> IN <SEP> KG
<tb><SEP> (FOR <SEP> IOOKG <SEP> FROM <SEP> ME- <SEP> MATERIALS <SEP> DRY <SEP> MATERIALS <SEP> NITROGEN <SEP> UNITS
<tb> INGREDIENTS <SEP> LANGE <SEP> FOOD <SEP> EN <SEP> KG <SEP> TOTAL <SEP> EN <SEP>% <SEP> FEEDER
<tb><SEP> FINAL) <SEP> (BY <SEP> REPORT <SEP> TO <SEP> ME- <SEP> (UF)
<tb><SEP> LANGE <SEP> FINAL
<tb> Floaters <SEP> Float <SEP> 43.67 <SEP> 4,367 <SEP> 2,2 <SEP> 1,5
<tb>"Agravit"<SEP> 55 <SEP> 35,750 <SEP> 13,750 <SEP> 38,5
<tb>"Melurolix"<SEP> 1 <SEP> 0.990
<tb>"Agralix"<SEP> 0.33 <SEP> 0.300 <SEP> - <SEP>
Mixture <SEP> food <SEP> 100 <SEP> 41,317 <SEP> 15,95 <SEP> 40
<tb> silence <SEP> final
<tb> TABLE III

<SEP> QUANTITY <SEP> IN <SEP> KG
<tb><SEP> (FOR <SEP> IOOKG <SEP> FROM <SEP> ME- <SEP> MATERIALS <SEP> XECHES <SEP> MATERIALS <SEP> NITROGEN
<tb> INGREDIENTS <SEP> LANGE <SEP> FOOD <SEP> EN <SEP> KG <SEP> TOTAL <SEP> EN <SEP>% <SEP> UNITS
<tb><SEP> FINAL) <SEP> (BY <SEP> REPORT <SEP> TO <SEP> ME- <SEP> FOURRAGERES
<tb><SEP> LANGE <SEP> FINAL) <SEP> (UF)
<tb> Sludge <SEP> Floating <SEP> 42 <SEP> 4.2 <SEP> 2.2 <SEP> 1.5
<tb>"Agravit"<SEP> 47 <SEP> 31.2 <SEP> 12 <SEP> 34
<tb>"Melurolix"<SEP> 1 <SEP> 0.90
<tb>"Agrelix"<SEP> 0.33 <SEP> 0.30
<tb>"Urea<SEP>46"<SEP> @ <SEP> 10 <SEP> 9 <SEP> 28.8 <SEP>
Mixture <SEP> food <SEP> 100 <SEP> 45.6 <SEP> 43 <SEP> 35.5
<tb> silence <SEP> final
<tb> K commercial designation of a product in which urea is the primary source
Nitrogen (usable only for cattle)

Claims (13)

claims  1 - Process for producing animal feed from floating sludge from organic and inorganic materials suspended in the effluents of food processing industries, in particular slaughterhouses, canning factories or dairies, the pH of the floated sludge being between about 1.8 and about 7, characterized in that the floated sludge recovered from the effluents is subjected to at least one settling so that the solids content of the settled sludge is between about 8 and about 12%; that the sludge is mixed with a substrate taken in an amount and a solids content such that the resulting food mixture has a solids content of between about 25 and about 50 X and that is also incorporated into sludge from other food components so as to obtain a suitable feed for animals.  2 - Process according to claim 1, wherein the pH of the starting sludge is weakly acidic and in particular between about 6 and about 7, characterized in that the floated sludge recovered from the effluents is subjected to a first settling during a period of time between 2 and 24 hours; a first acidification of the floated sludge from the first settling with a strong mineral acid is carried out; and that a second decantation is carried out for a period of time of between half an hour and 2 hours.  3 - Process according to claim 2, characterized in that the floated sludge is, prior to the first settling, subjected to treatment with hydrogen peroxide.  4 - Process according to one of claims 2 or 3, characterized in that is added to the sludge from the first settling, a mixture of iodine and phosphoric acid in proportions ranging from 0.5 to 2 X (in volume relative to the total volume of sludge settled).  5 - Process according to claims 2 and 4 taken simultaneously, characterized in that the first acidification with or without treatment with a mixture of iodine and phosphoric acid sludge from the first settling is completed by a steam bubbling allowing to bring the temperature of the sludge to a value close to 70-C.  6 - Process according to claim 2, characterized in that the sludge from the second decantation is mixed with a nitrogenous substrate and at least one premix, this mixture being subjected to a second acidification with a strong mineral acid.  7 - Process according to claims 2 and 6 taken if simultaneously, characterized in that the first and second acidifications are performed by concentrated sulfuric acid food grade.  8 - Process according to claim 6 characterized in that the food mixture from the second acidlfi cation is a liquid food, whose solids content is between 40 and 50 Z.  9 - Process according to claim 6, characterized in that in the first place, the food mixture from the second acidification is subjected to thermal dehydration to bring its dry matter content to a value of 70 Z; that secondly, the dehydrated product obtained is mixed with meat meal to constitute a solid food having a solids content of between 80 and 85%, this solid food being intended to be incorporated into a food formula for animals, especially for poulilla, at a rate of 5 to 15% (by weight relative to the total weight of the food formula).  10 - Process according to claim 2, characterized in that in the first place, the sludge from the second decantation is mixed with a cellulosic substrate taken in an amount such that the solids content of the resulting mixture is greater than 25%. and, preferably, between 40 and 45%, that secondly, the mixture (sludge-cellulosic substrate) is subjected to a thermal dehydration to bring its solids content to a value close to 70%, that in thirdly, the dehydrated product obtained is mixed with meat meal to constitute a solid food having a dry matter content of between 80 and 85%, this solid food being intended to be incorporated into a feed formula for animals, in particular to vo Size, 5 to 15% (by weight relative to the total weight of the food formula)  II - Process according to claim 1, wherein the pH of the starting sludge is between 1.8 and 2.5, characterized in that after decantation of the starting sludge they are mixed with a nitrogenous substrate and with at least one premix, to constitute a liquid food whose solids content is between 40 and 50 Z.  12 - Method according to one of claims 6 or 10, characterized in that the nitrogenous substrate contains from about 20 to about 30 Z of total nitrogenous material and a number of fodder units of between 0.5 and 1 (per kg of nitrogenous substrate) and that the premix (s) contain micro-nutrients, vitamins stabilizing agents, preservatives and agents to give the food the required appetability.  13 - Process according to claim 1, wherein the pH of the starting sludge is between 1.8 and 2.5, characterized in that firstly, the starting sludge is subjected to decantaton> then alkalization with lime or soda food grade so as to bring the pH of the sludge to a value of close to 4; that secondly, the sludge obtained is mixed with a cellulosic substrate taken in an amount such that the solids content of the resulting mixture is greater than 25% and preferably between 40 and 45%; that third, the mixture (sludge-cellulosic substrate) is subjected to thermal dehydration to bring its dry matter content to a value close to 70 Z; and fourthly, mixing the dehydrated product with meat meal to form a solid food having a solids content of between 80 and 85%, this solid food being intended to be incorporated into a food formula for animals, especially for poultry, at a rate of 5 to 15% (by weight relative to the total weight of the food formula).  14 - Method according to one of claims 12 or 13, characterized in that, prior to decantation, the flotation sludge is subjected to a pasteurization by steam bubbling.