FR2914537A1 - AGGLOMERANT ABSORBENT MASS - Google Patents

Abstract

Absorbent and agglomerating mass and in particular animal litter comprising at least 20% by weight of calcium sulphate and at least 10% by weight of an absorbent having an absorbency greater than 100%.

Description

Agglomerating absorbent mass The invention relates to absorbent masses,

  intended for the absorption of liquids, and in particular litter for animals. The solid absorbent masses in the form of powders or granules find particularly important use for the absorption of liquids on the soil (homes, industries, communication channels, ...). Another important use is the manufacture of absorbent litter for animals, mainly domestic animals such as cats and rodents. Very frequently, the entire absorbent mass is not soiled after being brought into contact with the liquid to be absorbed. It is then very interesting to be able to easily separate the soiled part of the intact part. It is then necessary to replace only this part, the rest can be reused. A simple and effective way to achieve this result is to use agglomerating absorbent masses. In such absorbent masses, the soiled part hardens and coalesces, which simplifies its separation from the part that has remained intact. An important parameter of the agglomerating absorbent masses is their agglomeration efficiency, i.e., the ratio of the weight of liquid absorbed to the weight of agglomerated absorbent mass. In the particular case of litter, the other desired properties include in particular the absence of repulsive effect vis-à-vis the animals for which they are intended, a good absorption of liquid animal waste, without sludge formation, sufficient mechanical strength to bear the weight of the animal, a low apparent specific weight and a low tendency to adhere to the ground, the feet of the animals or the container in use. Finally, it is also desired that the observation of the litter allows to detect certain anomalies of composition of the droppings, sign of a disease of the animal. Such litters are called diagnostic litters. Various categories of bedding have been proposed, but none presents all the desired optimum properties. A first category of litter is made up of porous mineral rocks of volcanic or fossil origin (diatomaceous earth) or vegetable matter such as wood chips, or straws (so-called vegetable litter). These litters

  The known properties generally have the desired properties as regards the apparent specific gravity and the adhesion. They are however not clumping, which implies the disadvantage of a large consumption of litter and requires frequent replacements of all of it.

  A second category of known litter is clay, such as bentonite, attapulgite and montmorillonite. Such litters are described in US Patent 5000115. These litters are clumping. However, they appeared to have a low agglomeration efficiency. To be able to play a diagnostic role, these two categories of known litters require the presence of specific additives whose color changes in contact with excrements having an abnormal composition. The invention aims to provide an improved litter which has excellent clumping properties and allows the diagnosis of certain diseases of the animal without requiring the presence of additional additives.

  Accordingly, the invention relates to a clumping and diagnostic litter consisting of particles, having an average white number of at least 85% and comprising at least 20% by weight of calcium sulphate and at least 10% by weight of an absorbent having an absorbency greater than 100%.

  Such litter has appeared to have an exceptional yield, which can reach or even exceed 50%. On the other hand, the average white index greater than 85% of the litter allows a simple and fast observation of the color of the urine. The white index is measured by the Hunter method. Indeed, when the animal has urinated in the litter, it is no longer white but has, thanks to the initial white index of most of its particles, a color very similar to that of urine of the animal. The average white index is an average value of the sample subjected to the measurement. The presence of a small amount, at most 10%, advantageously 5%, preferably 1% by weight of particles having a white index of less than 85% does not affect the diagnostic efficiency of the litter. These particles may be, for example, additives, in particular intended for the detection of specific diseases. The white index of the particles is measured by taking a sample comprising only such particles.

  However, in an advantageous embodiment of the use according to the invention, the litter is free of additives intended for the detection of diseases

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  specific to the animal. In a variation of this embodiment, the litter is even free from any particle having a white index of less than 80% Hunter, preferably 85%. In this variant the different particles constituting the litter therefore have a very similar white index.

  It has been observed that when the whiteness index is not greater than 85%, the color of the litter after contact with the urine may have a very different color from that of the urine, making detection impossible, from the color of the litter, a color anomaly of the urine itself. The normal color of the urine of the healthy animal being close to light yellow, any different color taken by the litter after contact with the urine, such as brown, green or blue or red, suggests the presence of a disease in animals. Detection of the possibility of illness in the animal can be done at home and without urine sampling. In a recommended variant of the litter according to the invention, the average white number is greater than 90%, preferably 92%, more preferably 94%. The litter comprises at least 20% by weight of calcium sulphate. It is recommended that it comprise at least 25%, advantageously at least 30%, preferably at least 35% and more preferably 40%.

  It is further recommended that it comprises at least 1%, advantageously at least 3%, preferably 5% calcium carbonate. In an advantageous variant, it also comprises at least at least 1%, advantageously at least 3%, preferably at least 5% of magnesium hydroxide.

  The litter according to the invention can advantageously come from the purification of sodium chloride solutions intended for the production of sodium carbonate by the ammonia method. These solutions, called brines, contain sulphates and carbonates. In order to separate them, lime is injected into the brine, which causes the crystallization of calcium sulphates and carbonates. The impurities are then separated from the brine and then dried at a temperature of between 175 and 225 ° C. They are then in the form of particles. It has been observed that the litter according to the invention must contain at least 10% by weight of an absorbent having an absorbency greater than 100%, as measured by standard NF V 19 002 of February 1993. It is recommended that this absorbency is greater than 120%, advantageously 140%, preferably 160% and particularly preferably 180%. It is on the other hand

  It is advantageous if the litter comprises at least 15%, preferably at least 20%, particularly preferably at least 25% by weight of such an absorbent. Various absorbents, such as, for example, absorbents based on plant fibers or advantageously based on silica gel or based on zeolites such as sepiolite may be suitable when their absorbency is at least 100% according to the standard mentioned above. Silica gel is preferred. In the litter according to the invention, it is recommended that the particles have a mean diameter D50 of between 500 and 3000 m. It is preferred that this diameter be between 600 and 2000 m, more preferably between 650 and 1500 m. Such litters, whose particles are finer, have agglomerating properties still improved. Certain animal diseases modify the composition of the urine of the animal but do not affect directly their color. In this case, in another advantageous embodiment of the litter according to the invention, it comprises an additive for the detection of specific diseases by changing its color in contact with the urine of the animal. For example, this additive may be copper sulfate, for the detection of a high amount of protein in the urine, a sign of renal failure. In fact, copper sulphate has a light blue color. In an alkaline medium, Cu ++ ions bind to proteins producing a colored purple complex. The change of color from blue to violet of the additive particles thus makes it possible to suspect renal insufficiency in the animal. The invention also relates to a method for diagnosing animal diseases applied to the urine of the said animals, according to which the animal urine in a litter according to the invention and the color of the litter is then compared to a table of associated urine color. to various diseases. In an advantageous variant of this method, the litter comprises at least one additive intended for detecting specific diseases by modifying its color in contact with the urine of the animal. The invention also relates to a diagnostic litter product for animals comprising (a) a litter according to the invention (b) a urine color table associated with various diseases.

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  The urine color table can be, for example, printed on a package containing the litter. It can also be provided separately, inside or attached to the outside of the package. The litter according to the invention has excellent properties of agglomeration and absorption. It also has a high return. These remarkable properties open many applications to any absorbent mass having a similar composition. Accordingly, the invention also relates to an absorbent mass and agglomerate in the form of particles, comprising at least 20% by weight of calcium sulfate and at least 10% by weight of an absorbent having an absorbency greater than 100%. The absorbent and agglomerating mass according to the invention is preferably in accordance with the various embodiments and variants of the litter according to the invention.

  The following examples serve to illustrate the invention. EXAMPLE 1 (not in accordance with the invention) An amount of lime for precipitating most of the sulphates and carbonates contained in the brine was injected into a brine intended for the production of sodium carbonate by the ammonia method. . The precipitated impurities were separated from the brine. These were dried at 200 ° C. in a rotary kiln. The granular material obtained was then sieved to extract the particles having a diameter of between 0.5 and 1.5 mm. More precisely, the particles had a diameter D10 of 576 μm, D50 of 1035 μm and D90 of 1452 μm.

  The composition of the particles obtained was analyzed and the results given in Table 1 were obtained. Table 1 CaSO4 64.6% CaCO3 14.3% Mg (OH) 2 15.2% NaCl 3.8% H2O 2.1% In a first test, 500 g of such particles were placed in a cylindrical container 20 cm in diameter and 10 cm in height. 10 ml of water were pipetted into the center of the sample in 5 seconds. After 20 minutes, the solidified litter portion was removed around the water injection point by means of a laboratory spoon and weighed. The

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  The results are shown in Table 2. The litter yield was evaluated by calculating the ratio between the weight of water absorbed (10g) and the litter weight consumed, which is the weight of the agglomerate, from which the 10 grams of water are absorbed.

  In a second test, a specimen of diameter 40 mm and height 25 mm was filled with the same particles and 8.5 ml of water were slowly injected into the test tube by means of a pipette. After having successively waited 10, 20, 30 minutes and 24 hours for the part of the sample around the injection point to agglomerate, the cohesion of the agglomerate of particles was tested each time by means of a body. cylindrical penetrant, placed on the surface of the agglomerate and guided by a device specially designed for this purpose, by measuring the depth of penetration. A cylindrical penetrating body, guided by a device specially designed for this purpose, on the sample and measuring the depth of penetration. The penetrating body had a diameter of 2, 2 mm, a height of 45 mm, a flat base, a weight of 3.3 g and was surmounted by an additional weight of 100g. The penetration results are shown in Table 2. The specific gravity per flow, the absorbency according to standard NFV 19002 and the particle size of the particles obtained after drying in the rotary kiln were also measured. The results are shown in Table 3. The white index of the particles was also measured. The index was measured using the Hunter method using a Datacolor Elrepho device. Before the measurement, the particles were ground so as to obtain the following diameters: ## EQU1 ## The results are shown in Table 3. Example 2 (in accordance with the invention) The procedure was as in the example 1 except that the particles obtained after drying in the rotary kiln were added with 21% by weight of silica gel having a bulk density of 400 g / dm3, a particle size D10 of 480 m, D50 of 725 m and D90 of 950 m. The absorbency for silica gel water, measured according to standard NF V 19 002, was 197%. The results are shown in Tables 2 and 3.

  Example 3 According to the invention) The procedure was as in Example 2 except that the particles obtained after drying in the rotary kiln were added with 28% by weight of silica gel. The results are shown in Tables 2 and 3.

  Example 4 (in accordance with the invention) The procedure was as in Example 2 except that the particles obtained after drying in the rotary kiln were added with 37% by weight of silica gel. The results are shown in Tables 2 and 3. Example 5 (not in accordance with the invention) In Example 5, a sample consisting solely of silica gel was taken and subjected to the penetration test. The penetrating body penetrated completely the sample, showing the absence of any clumping property. Table 2 Weight Penetration Penetration Penetrate Penetracglomerate. tion tion tion 10 min 20 min 45 min 24 h. Ex. 1 52g 24% <lmm <lmm <lmm <lmm Ex.2 40g 33% <lmm <lmm <lmm <lmm Ex. 3 32g 45% <lmm <lmm <lmm <lmm Ex.4 31g 47% 1, 2mm <lmm <lmm <lmm Ex. 5 - - Penetrate-Penetration- Penetration tion tion Table 3 Specific Weight Index Absorbance white particle size m D10 D50 D90 Ex. 1 93.7 958 g / 1 49% 576 1035 1452 Ex. 2 91.5 758 g / 1 76% 543 988 1423 Ex. 3 91.3 714 g / 1 86% 403 791 1258 Ex. 4 89.5 644 g / 1 99% 398 763 1237 Ex. The comparison of Examples 2 to 4 with Examples 1 and 5 shows the excellent sintering and yielding properties of litters according to the invention.

Claims (10)

  1. A particle clumping and diagnostic litter having an average white number of at least 85% and comprising at least 20% by weight of calcium sulphate and at least 10% by weight of an absorbent having an absorbency greater than 100%.   2. Litter according to the preceding claim, wherein the average white index is at least 90%.   3. Litter according to one of the preceding claims, comprising at least 40% by weight of calcium sulfate.   4. Litter according to one of the preceding claims, comprising at least 20% by weight of absorbent.   5. litter according to one of the preceding claims, wherein the absorbent has an absorbency greater than 160%.   6. Litter according to one of the preceding claims, comprising at least 5% calcium carbonate.   7. Litter according to one of the preceding claims, wherein the absorbent is based on silica gel.   8. Method of diagnosis of animal diseases applied to the urine of said animals, according to which the animal urine in a litter according to one of claims 1 to 7 and the color of the litter is then compared to a table of urine color associated with various diseases.   9. An animal litter product comprising: • litter according to one of claims 1 to 7 • a table of urine color associated with various diseases.   10. Absorbent and clumping mass comprising at least 20% by weight of calcium sulphate and at least 10% by weight of an absorbent having an absorbency greater than 100%.