A method for evaluating the water absorption and agglomeration performance of cat litter

Abstract

The present invention provides a method for evaluating the water absorption and agglomeration performance of cat litter, which comprises: providing a cat litter container with a containing cavity and filling the cat litter; providing a straw with a predetermined average flow rate and absorbing a predetermined volume of test solution; vertically placing the straw above the cat litter container, the liquid outlet of the straw having a predetermined height relative to the upper surface of the cat litter filled in the containing cavity; allowing the test solution to flow into the upper surface of the cat litter according to the predetermined average flow rate, and after the cat litter absorbs the test solution, taking out the cat litter to obtain a cat litter condensation agglomerate; measuring and calculating the performance parameters of the cat litter, the performance parameters including absorption time, agglomeration height, agglomeration gram weight, agglomeration liquid-sand ratio and agglomeration strength; and comprehensively evaluating the water absorption and agglomeration performance of the cat litter based on the results of the performance parameters. The present invention can quickly and effectively test the water absorption and agglomeration performance of cat litter.

Description

Technical Field

[0001] The invention relates to the technical field of cat litter performance detection, and in particular to a method for evaluating the water absorption and agglomeration performance of cat litter. Background Art

[0002] Cat litter is a granular material used to bury feces and urine for pet cats. It has the functions of absorbing water and deodorizing. It is used as cat bed bedding, which is convenient for owners to clean and improve the pet-raising environment. The invention of cat litter has brought benefits to cats entering urban families, especially clumping cat litter, which has good water absorption, deodorization and feces binding properties, is easy to clean and improves the pet-raising environment. Cat litter has become a necessity for urban cat owners.

[0003] At present, cat litter manufacturers are still generally troubled by quality fluctuations. This is certainly related to the unstable quality of raw materials used in cat litter and the complexity of production processes, but the industry lacks accurate and convenient evaluation methods. It is also an objective fact that many companies have a strong subjective and arbitrary control over cat litter quality, which leads to frequent customer complaints and quality accidents.

[0004] The water absorption and clumping performance is the most critical indicator of clumping cat litter, which is closely related to the consumer's experience. The method used in the existing group standard "T / CIQ11-2020 Tofu Cat Litter Specification" for evaluating the water absorption and clumping of cat litter is: take a cat litter sample and spread it in a sample basin about 8cm to 10cm thick, use a pipette to absorb 20mL of 1% sodium chloride solution at a temperature of 36℃ to 40℃, transfer it to an acid burette, adjust the acid burette to about 3cm away from the sample plane, open the acid burette, and let the solution flow into the sample within 30s. After all the solution flows out for 60s, take out the clumping sample and measure the longitudinal sample length (clumping height) to get the clumping property of the cat litter. According to this method, 3 groups of samples are taken at the same time to find the average value. Based on the test methods specified in the above standards, some existing cat litter manufacturers also test the clumping weight and clumping strength parameters of the clumping samples, and characterize the water absorption and clumping performance of cat litter by clumping height, clumping weight and clumping strength.

[0005] There are also patents that disclose some methods for evaluating the water absorption and agglomeration performance of cat litter, such as:

[0006] CN202110431049.2 provides a test method for the gram weight of clumps. Use a 20mL pipette to draw 20mL of 38°C saline solution and put it into a pre-fixed acid burette with the tube mouth 3cm away from the cat litter. Turn the acid titration to the maximum, quickly release the saline solution, let it stand for 20 seconds, then scoop out the clumping cat litter and weigh the mass on a scale.

[0007] CN202110309246.7 provides a water absorption test method: Pour the cat litter of the embodiment and the comparative example of the same weight of 100g into a 250mL beaker, shake the beaker by hand to make the poured cat litter evenly spread, and record the volume of the cat litter poured. Take physiological saline containing 1g / 100mL urea as the absorption object to simulate cat urine. Use a 100mL measuring cylinder to take 50mL and pour it into the cat litter from above to test the time required for the poured physiological saline to be completely absorbed.

[0008] CN202110781696.6 provides a method for testing the water absorption and clumping of cat litter with clumping effect. The test steps are as follows: prepare 7 clean cat litter boxes of the same commercial type, and pave each cat litter to be tested with a thickness of 10 cm ± 1 cm; pour 80 mL of physiological saline containing 1 g / 100 mL urea at a height of 5 cm above the cat litter, and test the time required for it to completely absorb water. After clumping, remove the cat litter clumps to observe their fragmentation and adhesion to the bottom.

[0009] According to the group standard "T / CIQ11-2020 Tofu Cat Litter Specification" and the test methods disclosed in the patent, the following problems are currently prevalent:

[0010] (1) The cat litter is spread in a basin or a conventional large container, and the thickness of the spread is large, and the amount of test sample is large (up to 2 to 5 kg is required for one test). Most of the cat litter that has not played a role is easily contaminated, which is not convenient for parallel testing of multiple groups of samples, which not only wastes materials but also affects efficiency.

[0011] (2) When adding liquid using a burette, syringe, pouring, etc., the flow of the liquid is unstable and cannot be controlled, resulting in poor precision of the test results. Many of them remain at the level of rough qualitative comparison, making it difficult to effectively and accurately evaluate the water absorption and clumping performance of cat litter. Summary of the invention

[0012] In view of the deficiencies of the prior art, the present invention provides a method for evaluating the water absorption and clumping performance of cat litter, so as to quickly and effectively evaluate the water absorption and clumping performance of cat litter.

[0013] In order to achieve the above object, the present invention adopts the following technical solution:

[0014] A method for evaluating the water absorption and agglomeration performance of cat litter, comprising:

[0015] A cat litter container with a containing cavity is provided and cat litter is filled in the containing cavity; wherein the containing cavity is of a structure that is larger at the top and smaller at the bottom, the height of the containing cavity is 20 mm to 100 mm, the width of the top is 40 mm to 150 mm, the width of the bottom is 25 mm to 80 mm, and the taper is 0.03 to 3.0;

[0016] Providing a pipette with a predetermined average flow rate and sucking a predetermined volume of test solution;

[0017] The straw is vertically placed above the cat litter container, with the liquid outlet of the straw having a predetermined height relative to the center of the upper surface of the cat litter filled in the accommodating cavity;

[0018] Allow the test solution to flow into the upper surface of the cat litter at a predetermined average flow rate, and after the cat litter has completely absorbed the test solution, take out the cat litter to obtain agglomerated cat litter lumps;

[0019] Measuring or calculating performance parameters of cat litter, the performance parameters including absorption time, agglomeration height, agglomeration weight and / or agglomeration liquid-to-sand ratio, and agglomeration strength;

[0020] Based on the results of the performance parameters, a comprehensive evaluation is performed on the water absorption and agglomeration performance of the cat litter.

[0021] In a specific scheme, the absorption time is defined as: the time taken from the test solution stopping flowing out of the straw to the time the test solution on the surface of the cat litter is completely absorbed; the clumping height is defined as: the maximum vertical height from the upper surface of the cat litter agglomerate with added test solution to the bottom; the clumping weight is defined as: the weight in grams of the cat litter agglomerate; the clumping liquid-to-sand ratio is defined as: the ratio of the weight of the liquid in the cat litter agglomerate to the weight of the cat litter; the clumping strength is defined as: the percentage of the weight of the largest agglomerate remaining after a drop test under specified test conditions to the weight of the cat litter agglomerate before the drop.

[0022] More specifically, the accommodating cavity is a cup-shaped or bowl-shaped structure that is larger at the top and smaller at the bottom, approximately a truncated cone, with an inner height of 30mm to 60mm, an inner diameter of 60mm to 80mm at the top, an inner diameter of 30mm to 50mm at the bottom, and a taper of 0.05 to 2.0.

[0023] Specifically, the pipette refers to a pipette with one scale or marking or a graduated pipette with multiple graduations.

[0024] Specifically, the predetermined volume is 5 mL to 20 mL, the predetermined height is 0.5 cm to 4 cm, and the predetermined average flow rate is 0.7 mL / s to 1.3 mL / s.

[0025] More specifically, the predetermined volume is 10 mL, the predetermined height is 2 cm, and the predetermined average flow rate is 1.0 mL / s.

[0026] Specifically, the temperature of the cat litter is 20°C to 30°C.

[0027] Specifically, the test solution can be selected as pure water, saline or urea saline, and the temperature of the test solution is 38.0°C to 39.5°C, preferably 38.0°C. The test solution can be maintained at a predetermined temperature by water bath heating, constant temperature electric heating, etc.

[0028] Specifically, the pure water refers to laboratory water that meets the third-grade water standard or above in GB / T 6682, and can be produced by reverse osmosis, distillation, ion exchange and other processes; the brine refers to an aqueous solution containing 0.9% or 1% sodium chloride; the urea brine refers to an aqueous solution containing 1% urea and 0.9% sodium chloride.

[0029] Specifically, the cat litter container is a transparent cat litter container; after the cat litter absorbs the test solution, the cat litter is taken out to obtain cat litter condensed clumps.

[0030] The method for evaluating the water absorption and agglomeration performance of cat litter provided by the present invention has the following beneficial effects:

[0031] (1) The test is conducted based on a cat litter container with a specific structure. The amount of cat litter sample used in each test is small. On the one hand, it can save cat litter sample materials and avoid waste; on the other hand, it is very conducive to parallel testing of multiple groups of samples at the same time, thereby improving the test efficiency.

[0032] (2) The test solution is added to the surface of the cat litter sample using a pipette. The amount and flow rate of the test solution can be controlled more accurately and is not easily affected by human operation. The test error can be reduced and the precision of the test results can be improved. The water absorption and clumping performance of the cat litter can be effectively tested and evaluated, thereby better controlling the quality of the cat litter.

[0033] (3) In addition to the existing evaluation parameters of cat litter water absorption and clumping performance characterized by clumping height, clumping weight and clumping strength, the absorption time and clumping liquid-sand ratio are added to improve the stability and accuracy of the evaluation results of cat litter water absorption and clumping performance. DETAILED DESCRIPTION

[0034] In order to make the objectives, technical solutions and advantages of the present invention more clear, the specific implementation modes of the present invention are described in detail below.

[0035] The embodiment of the present invention provides a method for evaluating the water absorption and agglomeration performance of cat litter, which comprises the following steps:

[0036] Step S10: providing a cat litter container having a containing cavity and filling the cat litter into the containing cavity.

[0037] Among them, the accommodating chamber is a structure that is large at the top and small at the bottom. This structure is conducive to reducing the horizontal pressure brought by the cavity wall when the cat litter absorbs water and expands, making its upward expansion phenomenon more obvious, and at the same time facilitating the removal of cat litter lumps. The size of the container can be selected according to the water absorption and agglomeration performance of the cat litter. Under the condition of ensuring normal testing (lumps will not stick to the bottom and wall), the accommodating chamber can be as small as possible to save the sample amount for a single test. The height (depth) of the accommodating chamber should generally be higher than the agglomeration height of the cat litter, so as to avoid the cat litter sticking to the bottom during the test and affecting the accurate determination of indicators such as agglomeration height, agglomeration weight and agglomeration strength. However, in production quality control, the height of the accommodating chamber can sometimes be fixed (without paying attention to whether its height is higher than the agglomeration height of the cat litter) to quickly judge whether the cat litter sticks to the bottom or the degree of sticking to the bottom. For most cat litter samples, it is recommended that the accommodating chamber height is 20mm to 100mm, the top width is 40mm to 150mm, the bottom width is 25mm to 80mm, and the taper is 0.03 to 3.0.

[0038] It should be noted that the accommodating cavity has a structure that is larger at the top and smaller at the bottom, and its cross section can be circular, square or other polygonal, or any other irregular shape. The width dimension mentioned above: when the cross section of the accommodating cavity is circular, the width dimension refers to the diameter; when the cross section of the accommodating cavity is other shapes, the width dimension refers to the distance between the two points with the largest spacing in the cross section, for example, when the cross section is square or rectangular, the width dimension refers to the length of the diagonal of the cross section. Most preferably, the accommodating cavity has a structure that is larger at the top and smaller at the bottom and gradually becomes smaller from top to bottom, and its cross section is circular.

[0039] In some preferred technical solutions, the accommodating cavity is a cup-shaped or bowl-shaped structure that is larger at the top and smaller at the bottom, approximately a truncated cone, with an inner height of 30mm to 60mm, an inner diameter of 60mm to 80mm at the top, and an inner diameter of 30mm to 50mm at the bottom, and a taper of 0.05 to 2.0.

[0040] As a preferred solution, in the embodiment of the present invention, commonly used accommodating cavity size specifications are, for example:

[0041] Inner height 30mm, top inner diameter 61mm, bottom inner diameter 54mm, taper 0.23;

[0042] Inner height 45mm, top inner diameter 62mm, bottom inner diameter 53mm, taper 0.20;

[0043] Inner height 60mm, top inner diameter 69mm, bottom inner diameter 42mm, taper 0.45;

[0044] Inner height 40mm, top inner diameter 80mm, bottom inner diameter 40mm, taper 1.0.

[0045] The cat litter container is preferably transparent to facilitate observation of the cat litter sample in the container during testing. The material thereof may be PE, PET, PS, PVC, PC, glass, etc.

[0046] After the cat litter sample is filled in the accommodating cavity, it is shaken or scraped flat so that the surface of the cat litter sample is flush with the top surface of the cat litter container. The temperature of the cat litter is preferably controlled at 20°C to 30°C.

[0047] Step S20: providing a pipette with a predetermined average flow rate and sucking a predetermined volume of test solution.

[0048] The pipette can be a pipette with only one scale or mark, or a graduated pipette with multiple scales, or a homemade glass tube, as long as the volume of the test solution sucked and the outflow time are within the required range and each operation is as consistent as possible. For simplicity, a common 10 / 20mL graduated pipette on the market can be directly selected, and its flow rate can be checked and calibrated before use.

[0049] The flow rate of the pipette is the average flow rate when the predetermined volume of liquid in the pipette is naturally drained. Considering that the last small amount of liquid in the pipette flows out very slowly, the last 1mL to 2mL of liquid is generally discarded when calculating the average flow rate, and the average flow rate of the front liquid is calculated. In the embodiment of the present invention, the predetermined average flow rate is preferably 0.7mL / s to 1.3mL / s, and more preferably 1.0mL / s.

[0050] In some specific technical solutions, the predetermined volume of the test solution may be 5 mL to 20 mL. In a preferred solution, the predetermined volume of the test solution is 10 mL.

[0051] The test solution can be pure water, saline or urea saline, and the temperature of the test solution is set to 38.0°C to 39.5°C, preferably 38.0°C. The test solution can be kept at a predetermined temperature by water bath heating, constant temperature electric heating, etc.

[0052] Specifically, the pure water refers to laboratory water that meets the third-grade water standard or above in GB / T 6682, and can be produced by reverse osmosis, distillation, ion exchange and other processes; the brine refers to an aqueous solution containing 0.9% or 1% sodium chloride; the urea brine refers to an aqueous solution containing 1% urea and 0.9% sodium chloride.

[0053] In a preferred solution, the test solution uses pure water. Compared with tap water, drinking water, etc., pure water is more likely to ensure the consistency of water quality. Compared with salt water or urea salt water, pure water is more convenient to use, avoiding the formation of scale on contact parts such as pipettes and the change of the concentration of the salt solution due to water volatilization in long-term constant temperature, and avoiding the long-term corrosion of metals such as constant water kettles.

[0054] Step S30: fix the straw above the cat litter container, wherein the liquid outlet of the straw has a predetermined height relative to the upper surface of the cat litter filled in the accommodating cavity.

[0055] In some specific technical solutions, the predetermined height is preferably 0.5 cm to 4 cm, and more preferably 1 cm to 2 cm.

[0056] Step S40, allowing the test solution to flow into the upper surface of the cat litter at a predetermined average flow rate, and after the cat litter has completely absorbed the test solution, taking out the cat litter to obtain cat litter condensed clumps.

[0057] In a preferred embodiment, after the cat litter absorbs the test solution, the cat litter is left to stand for 10 to 20 seconds and then the cat litter is taken out to obtain agglomerated cat litter clumps.

[0058] Step S50, measuring and calculating the performance parameters of the cat litter, wherein the performance parameters include absorption time, agglomeration height, agglomeration weight, agglomeration liquid-sand ratio and agglomeration strength.

[0059] The absorption time is defined as the time from when the test solution stops flowing out of the straw to when the test solution on the surface of the cat litter is completely absorbed. The absorption time is used to assist in evaluating the speed of cat litter water absorption, but this data should be judged in combination with the clumping height. Under the same clumping height, the smaller the absorption time, the better.

[0060] The agglomeration height is defined as the maximum vertical height from the upper surface of the cat litter agglomerate to the bottom of the added test solution. The agglomeration height is the core indicator of the water absorption performance of cat litter. It is closely related to the water absorption speed of cat litter and is also a parameter for evaluating whether cat litter is easy to stick to the bottom during use. The smaller the agglomeration height, the better.

[0061] The agglomeration weight is defined as the weight of the agglomerated lumps of the cat litter. The agglomeration weight should not be used to evaluate the waste degree of cat litter, and the smaller the agglomeration weight, the better.

[0062] Wherein, the agglomeration liquid-sand ratio is defined as: the ratio of the liquid weight in the cat litter agglomeration mass to the cat litter weight. That is: agglomeration liquid-sand ratio = test solution weight / (agglomeration gram weight - test solution weight). The agglomeration liquid-sand ratio can be used to evaluate the liquid absorption degree of agglomeration. The larger the agglomeration liquid-sand ratio, the better. Under the same agglomeration liquid-sand ratio, the harder the agglomeration is. When the amount of test solution added is fixed and consistent (such as unified as 10g), the agglomeration liquid-sand ratio and the agglomeration gram weight can be converted to each other, and the ratio between them is fixed, so the agglomeration gram weight and the agglomeration liquid sand can be controlled by any one of the indicators; when the amount of test solution added is not completely consistent (such as some are 10mL, some are 20mL), it is easier to compare and analyze using the agglomeration liquid-sand ratio.

[0063] The clumping strength is defined as: the weight of the largest remaining agglomerate after a drop test under specified test conditions (eg, at a specific height) is the percentage of the weight of the agglomerated agglomerate of the cat litter before the drop.

[0064] Step S60: Comprehensively evaluate the water absorption and agglomeration performance of the cat litter based on the performance parameter results obtained in the above step S50.

[0065] It should be noted that, based on the high uniformity of the composition and particle distribution of cat litter, in order to reduce errors, each cat litter sample should be tested in parallel three or more times according to the above steps S10 to S50 if conditions permit, and the arithmetic mean of each valid test of absorption time, agglomeration height, agglomeration weight, agglomeration liquid-sand ratio and agglomeration strength shall be taken as the reported result; when there is a large deviation between the parallel test results or the credibility of individual data is in doubt, the test should be repeated.

[0066] The evaluation method of the water absorption and clumping performance of cat litter provided in the above embodiment: first, the test is carried out based on a cat litter container with a specific structure, and the amount of cat litter sample used in each test is small. On the one hand, it can save cat litter sample materials and avoid waste; on the other hand, it is conducive to parallel testing of multiple groups of samples at the same time, thereby improving the test efficiency. Secondly, the test solution is sucked by a straw and naturally flows onto the surface of the cat litter sample, which can more accurately control the amount and flow rate of the test solution, improve the stability of the test results, reduce the test error, and effectively evaluate the water absorption and clumping performance of cat litter, thereby better controlling the quality of cat litter. Furthermore, on the basis of the existing characterization of the water absorption and clumping performance of cat litter by clumping height, clumping weight and clumping strength, the evaluation parameters of absorption time and clumping liquid-sand ratio are added, which improves the stability and accuracy of the evaluation results of the water absorption and clumping performance of cat litter.

[0067] The technical solution of the present invention is further described in detail below in conjunction with some specific test examples.

[0068] The information of the cat litter samples used in the following test examples is shown in Table 1. The selected samples include 5 types of tofu cat litters, 5 types of bentonite cat litters and 2 types of mixed cat litters, all of which are from commercially available cat litter products with the highest current sales.

[0069] Table 1 Basic information of cat litter samples

[0070]

[0071]

[0072] The test solution information used in the following test examples is shown in Table 2.

[0073] Table 2 Basic information of test solution

[0074]

[0075] Test Example 1

[0076] Three tofu cat litter samples (numbered A, B, C1) and three bentonite cat litter samples (numbered E, F, G) were selected, and their water absorption and agglomeration performance was tested by the method provided in the embodiment of the present invention. The three key indicators of agglomeration height, agglomeration weight and agglomeration strength were selected, and their relative standard deviations (RSDs) were used to evaluate the precision of the test. The results are shown in Table 3.

[0077] Table 3 Cat litter sample parallel test

[0078]

[0079]

[0080] From the data in Table 3, it can be seen that the above cat litter test samples were tested in multiple groups in parallel, and the RSD of clumping height was 5.6%-10.9%, with poor precision; the RSD of clumping weight was 0.82%-3.56%, with good precision; the RSD of clumping strength was 0.86%-7.67% for tofu cat litter and 0.53%-1.29% for bentonite.

[0081] The above test has strict regulations on the factors that may affect the test (water temperature, cat litter temperature, test solution dosage and flow rate). The method itself has a very small error, and the precision is mainly related to the properties of the cat litter sample.

[0082] The overall precision of the clumping height is poor, mainly because: the clumping height data is small, the difference between the clumping height and the scale of the cat litter particles is not large enough, and there is an error in measuring the clumping height. Most tofu cat litters have a diameter of 1.5mm to 3mm and a length of 5mm to 30mm; the diameter of bentonite cat litters is 0.5mm to 4mm. The unevenness of the particle size and the randomness of the arrangement have a great influence on the clumping height. Since cat litters are all solid mixtures, there is a certain degree of unevenness in the chemical composition (whether it is tofu cat litter or bentonite cat litter), and there is a greater unevenness in the physical form (particle shape, size, posture), and the physical form can have a significant impact on the water absorption and clumping performance of cat litter. Increasing the number of parallel tests and conducting statistical analysis on the test data are particularly important for more accurate evaluation of cat litter quality.

[0083] Test Example 2

[0084] The four test solutions in Table 2 were selected, and the water absorption and agglomeration properties of the cat litter samples were tested using the method provided in the embodiment of the present invention to investigate the influence of the composition of the test solutions on the water absorption and agglomeration properties of the cat litter. The results are shown in Table 4.

[0085] Table 4 Effect of the composition of the test solution on the water absorption and agglomeration performance of cat litter

[0086]

[0087]

[0088]

[0089] From the data in Table 4, we can know that:

[0090] For tofu cat litter and mixed cat litter samples, different test solutions (pure water, salt water, urea salt water) were used for testing, and the test phenomenon, absorption time, agglomeration height, agglomeration weight, agglomeration liquid-sand ratio, agglomeration strength and other results were not much different. The slight difference between the data is more related to the error caused by the uniformity of the cat litter sample itself.

[0091] For bentonite cat litter, it may be affected by the type of test solution. Some bentonite cat litters (probably mainly sodium-based, such as E and F) use pure water testing, and the absorption time is shorter, the agglomeration height is lower, and the liquid-to-sand ratio is higher, indicating that this type of bentonite has a better absorption effect on pure water, and a relatively poor absorption effect on urea brine and salt water.

[0092] Another part of bentonite cat litter (probably mainly calcium-based bentonite, such as H1 and H2), on the contrary, performed better when tested with saline or urea saline: the agglomeration height was significantly reduced, and the liquid-sand ratio was increased; although the absorption time was slightly longer than that of pure water, it was mainly due to the large amount of water leaking underwater during the pure water test, which caused the illusion of no water on the surface.

[0093] For some bentonite samples (such as G), the test results using different test solutions (pure water, salt water, and urea salt water) showed no significant difference. This may be because the exchange capacity of monovalent and divalent cations in their composition reached equilibrium at a certain point.

[0094] Cat urine was used to test and compare bentonite cat litter samples E, F, H1, and H2. As shown in Table 4, the results show that for these samples, the results of urea brine are closer to cat urine, followed by brine, and pure water has the largest deviation (especially samples H1 and H2).

[0095] The above experimental data show: test the water absorption and agglomeration performance of bentonite cat litter, use urea salt solution or be closer to cat urine, particularly for poor quality bentonite cat litter (such as H1, H2), use pure water and use urea salt solution test result can appear large deviation, urea salt solution result or be closer to cat urine. But, whether cat urine will appear different from the above experimental conclusion due to differences such as variety, age, diet, physical condition, etc., still needs further study. For high-quality bentonite cat litter, pure water and urea salt solution test result are not very different, for low-quality bentonite cat litter, pure water measured data is obviously not good, from another angle, adopt pure water can more obviously distinguish the quality of bentonite. Therefore, the test solution in the technical scheme of the present invention preferably uses pure water.

[0096] Judging from the overall samples of tofu cat litter, bentonite cat litter and mixed cat litter, it is feasible to use pure water instead of saline solution and urea saline solution.

[0097] Test Example 3

[0098] Under a room temperature of 25°C, pure water at different temperatures of 8°C, 15°C, 25°C, and 38°C were selected as test solutions, and the water absorption and agglomeration properties of various cat litter samples were tested using the method provided in an embodiment of the present invention to investigate the effects of test solutions at different temperatures on the water absorption and agglomeration properties of cat litter. The results are shown in Table 5.

[0099] Table 5 Water absorption and agglomeration performance of cat litter under different test solution temperature conditions

[0100]

[0101]

[0102] From the data in Table 5, it can be seen that the temperature of the test solution (pure water) has a great influence on the test results, especially on the agglomeration height. For some tofu cat litters, low temperature will significantly increase the agglomeration height, reduce the water absorption rate, and reduce the degree of water absorption expansion, which is manifested as being more likely to stick to the bottom when used. In fact, considering that the normal body temperature of a cat is generally 38.0℃~39.5℃, the temperature of cat urine when discharged is close to the body temperature, so the temperature of the test solution in the scheme of the present invention is preferably 38.0℃~39.5℃, and more preferably 38.0℃.

[0103] In addition to the influence of the test solution temperature, the temperature of the cat litter may also affect the results. Since the production of tofu cat litter requires granulation, drying and other processes, if the online sampling is not fully cooled, the temperature of the cat litter is often higher than the room temperature. In addition, in most cases, the temperature of the cat litter is close to the ambient temperature, and the indoor ambient temperature can fluctuate in the range of 5℃ to 35℃ or even wider due to seasonal and regional differences. The impact of the cat litter temperature on the test results must be considered.

[0104] For this reason, the tofu cat litter samples were divided into multiple portions and placed in a 40°C oven, a 25°C room temperature, and a 4°C refrigerator for a period of time. A thermometer was used to monitor the actual temperature of the cat litter. Cat litters with temperatures of 38°C, 30°C, 25°C, 15°C, and 4°C were selected. Their water absorption and agglomeration properties were tested in time with 38°C pure water at a room temperature of 25°C. The cat litter samples at each temperature were measured three times in parallel, and the results were averaged. The results are shown in Table 6.

[0105] Table 6 Water absorption and agglomeration performance of tofu cat litter at different cat litter temperatures

[0106]

[0107]

[0108] From the data in Table 6, we can know that the temperature of cat litter will also affect its water absorption and clumping performance. In particular, cat litters at 5℃ and 15℃ generally show a significant increase in clumping height and a significant decrease in clumping strength. This is because low temperature will slow down the absorption rate of cat litter, which also means that cat litter is more likely to stick to the bottom when used in cold indoor places in winter. The test results of cat litters at 38℃, 30℃, and 25℃ are not very different, but overall it can be seen that the performance of 38℃ cat litter is generally better than that of 25℃, which means that for the same cat litter, taking warm cat litter from the production line for testing may have better water absorption and clumping performance than taking cat litter that has been fully cooled to room temperature for testing.

[0109] In order to reduce this test data deviation, it is recommended to test the cat litter samples at a constant narrow temperature range (such as 20℃~30℃), or to establish a corresponding relationship curve between the various parameters of water absorption and clumping performance and temperature for specific cat litter, and set different control ranges according to different temperatures.

[0110] Test Example 4

[0111] When the burette, dropping funnel, pipette, graduated pipette and other liquid adding devices are fully open, they all rely on the pressure generated by the liquid's own gravity to drive the liquid out. In fact, the flow rate decreases gradually. The water absorption state of cat litter is more affected by the initial high flow rate. However, for a specific graduated pipette, after the test liquid type, temperature, and dosage are fixed, its outflow state is no longer affected by human factors. Therefore, we can better guarantee the precision of the parallel test results by measuring its average flow rate and using it as a standard.

[0112] In order to investigate the influence of the flow rate and amount of the test solution on the test results, in this test example, the method provided in the embodiment of the present invention was adopted: (1) graduated pipettes with average flow rates of 2 mL / s, 1 mL / s, and 0.55 mL / s were selected, and their water absorption and agglomeration performances were tested and compared under the condition of the same test solution amount of 10 mL; (2) 5 mL and 20 mL graduated pipettes with an average flow rate of 1 mL / s were selected to investigate the influence of the test solution amount on the water absorption and agglomeration performance. The results are shown in Table 7.

[0113] Table 7 Effect of flow rate and test solution dosage on water absorption and agglomeration performance

[0114]

[0115]

[0116] From the data in Table 7, it can be seen that the test solution flow rate has a great influence on the test results of water absorption and agglomeration performance. When the test solution dosage is fixed at 10mL, with the decrease of flow rate of 2mL / s, 1mL / s, and 0.55mL / s, the agglomeration height decreases, the water absorption rate or liquid-sand ratio increases, the agglomeration strength increases slightly, the absorption time of tofu cat litter and mixed cat litter increases significantly, and the absorption time of bentonite cat litter increases not significantly. When the flow rate is fixed (1mL / s), using 5 / 10 / 20mL volume of pure water test solution, the agglomeration height increases (but not proportional to the volume of pure water), the water absorption rate or liquid-sand ratio increases, the agglomeration strength increases slightly, the absorption time of tofu cat litter and mixed cat litter increases significantly, and the absorption time of bentonite cat litter increases not significantly.

[0117] Therefore, the setting of cat litter water absorption and agglomeration performance index needs to be strictly matched with the flow rate and dosage of the test solution. The influence of the test solution flow rate on the results even exceeds the influence of the dosage. According to statistics, the urine volume of an adult 5kg medium-sized cat is about 20mL~30mL at a time, and it takes 20 seconds to 30 seconds to urinate, with an average flow rate of about 1mL / s, while the average flow rate of peeing by kittens or old cats is generally less than this value. Therefore, it is reasonable to use a test solution flow rate of about 1mL / s. At the same time, it is more convenient to use a graduated pipette with a flow rate of about 1mL / s. The liquid will not be splashed easily without waiting too long. For most cat litters, 10mL~20mL of test solution can effectively evaluate the quality of cat litters, and it has good operability. If the test solution dosage is too small (such as 5mL), the relative error is large; if the test solution dosage is increased, the error is reduced, but the single test sample dosage and test time are both linearly increased. 10mL is a preferred dosage, because the graduated pipette of this specification is easy to reach, the errors of each indicator are also small, saving samples and time. When using 20 mL of water, the sample volume and solute cavity need to be increased, and the absorption time and water addition time of some samples are significantly increased.

[0118] Cat litter, as a solid mixture, has a large degree of heterogeneity. Parallel testing is an effective way to reduce errors. However, parallel determination increases the sample dosage and test time exponentially. Reducing the single dosage and measurement time is particularly important in production quality inspection. The dosage of the test solution is 10mL and the flow rate is about 1mL / s, which is the preferred solution.

[0119] Test Example 5

[0120] Two types of tofu cat litters (A and C1) and two types of bentonite cat litters (E and G) were selected, and the method of the present invention was used to compare with the method of "T / CIQ11-2020 Tofu Cat Litter Specification" and patent application CN202011477196.5. The comparison dimensions include: sample dosage, test time, and parallel test precision (evaluated by RSD).

[0121] In the method of the present invention, 38°C pure water is used as the test solution, the temperature of cat litter is 25°C, water is added with a 10mL graduated pipette, 10mL of the test solution is taken each time, the average flow rate is 1mL / s, and a transparent PE cup is used to hold the cat litter sample, and the cup dimensions are: inner height 45mm, mouth inner diameter 62mm, bottom outer diameter 54mm.

[0122] In the T / CIQ11-2020 method, a 38°C 1% sodium chloride aqueous solution is used as the test solution, the cat litter temperature is 25°C, and the liquid is added with a 25mL acid pipette from 0 to 20 each time, that is, 20mL of the test solution is added, and the addition time is 25 seconds. A cat litter basin (bottom size is about 30cm×40cm) is used to hold the cat litter sample.

[0123] In the method of patent application CN202011477196.5, 38°C 1% sodium chloride aqueous solution is used as the test solution, the cat litter temperature is 25°C, and the liquid is added with a syringe, 20 mL of liquid is added each time, and the liquid addition time is controlled to be about 10 seconds as much as possible. A 500 mL beaker is used to hold the cat litter sample. The test results of the three methods are compared in Table 8.

[0124] Table 8 Comparison of the three methods

[0125]

[0126] From this, we can see that the method of the present invention saves sample consumption, takes less time, and has higher precision of parallel test data. This is due to the fact that the present invention uses a suitable cat litter container to hold the sample according to the characteristics of the cat litter, which greatly saves the sample; uses a graduated pipette, which makes it accurate and convenient to absorb and add the test solution; uses 10mL of water instead of more water, which reduces the time for absorption and addition, and also saves sample consumption.

[0127] In addition to the large amount of sample used, T / CIQ11-2020 has great inconvenience in operation: it is not easy to manually close the valve of the burette exactly when 20 mL is added each time (unless it is added slowly as approaching the titration endpoint, but this will cause flow rate changes), resulting in poor accuracy of water addition each time, which directly affects the accuracy of the gram weight of the agglomerate; and the two processes of adding liquid to the burette and discharging liquid from the burette are significantly longer than those of the present invention. When operating in an environment where the room temperature and liquid temperature are greatly different, the temperature of the test solution in the burette is more likely to fluctuate and affect the precision of the test results.

[0128] The precision of the CN202011477196.5 method is relatively poor, mainly because it uses a syringe to add liquid, and the amount of liquid added each time may have a large deviation. It is difficult for general experimenters to manually control the addition of 20mL of liquid in 10 seconds and keep it consistent each time, and this error between people may be even greater. Accurate addition volume and consistent addition flow rate each time are prerequisites for ensuring the precision of the test results.

[0129] In summary, the scheme of the embodiment of the present invention provides an evaluation index and an evaluation method for the water absorption and clumping performance of cat litter. Using commercially available representative clumping cat litter as a sample, the influence of test solution composition, dosage, flow rate, temperature, cat litter temperature and other factors on each index is systematically studied, and its law is explained, which is convenient for optimizing and controlling the key influencing factors in the method, and the precision and accuracy of the method are guaranteed. The cat litter sample is contained in a container with a specific structure, which saves materials and is convenient for parallel testing; the pipette liquid addition method with suitable flow rate and capacity is adopted, which has high precision, small human error, convenient operation and time saving; pure water is used as the test solution to make the operation more convenient. This method can be used for cat litter production enterprises, research institutions, and quality inspection institutions to evaluate the quality of cat litter, and can be used for standardization to solve the problems of the existing industry.

[0130] The above is only a specific implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A method for evaluating the water absorption and agglomeration performance of cat litter, characterized in that: include: A cat litter container with a receiving cavity is provided and cat litter is filled in the receiving cavity; wherein the receiving cavity is in a structure that is larger at the top and smaller at the bottom, the height of the receiving cavity is 20 mm to 100 mm, the top width is 40 mm to 150 mm, the bottom width is 25 mm to 80 mm, and the taper is 0.03 to 3.0; the receiving cavity is in a cup-shaped or bowl-shaped structure that is larger at the top and smaller at the bottom and is approximately truncated; Providing a pipette with a predetermined average flow rate and sucking a predetermined volume of test solution, the pipette is a pipette with a scale or marking or a graduated pipette with multiple graduations, the predetermined volume is 5 mL to 20 mL, and the predetermined average flow rate is 0.7 mL / s to 1.3 mL / s; The straw is vertically placed above the cat litter container, wherein the liquid outlet of the straw has a predetermined height relative to the upper surface of the cat litter filled in the accommodating cavity, and the predetermined height is 0.5 cm to 4 cm; Allow the test solution to flow into the upper surface of the cat litter at a predetermined average flow rate, and after the cat litter has completely absorbed the test solution, take out the cat litter to obtain agglomerated cat litter lumps; Measure and calculate the performance parameters of cat litter, including absorption time, clumping height, clumping weight, clumping liquid-sand ratio and clumping strength; perform parallel tests three or more times according to the above steps, and take the arithmetic mean of each valid test for absorption time, clumping height, clumping weight, clumping liquid-sand ratio and clumping strength as the reported result; repeat the test when there is a deviation between the parallel test results or the credibility of individual data is questionable; Based on the results of the performance parameters, the water absorption and agglomeration performance of the cat litter is comprehensively evaluated.

2. The method for evaluating the water absorption and agglomeration performance of cat litter according to claim 1, wherein: The absorption time is defined as the time from when the test solution stops flowing out of the straw to when the test solution on the surface of the cat litter is completely absorbed; The agglomeration height is defined as: the maximum vertical height from the upper surface of the cat litter agglomerate to the bottom of the added test solution; The agglomeration weight is defined as: the weight in grams of the agglomerated agglomerates of the cat litter; The agglomeration liquid-sand ratio is defined as: the ratio of the weight of the liquid in the agglomerated mass of cat litter to the weight of the cat litter; The clumping strength is defined as: the percentage of the weight of the largest remaining agglomerate after a drop test under specified test conditions to the weight of the agglomerated agglomerate of the cat litter before the drop.

3. The method for evaluating the water absorption and agglomeration performance of cat litter according to claim 1, wherein: The predetermined volume is 10 mL, the predetermined height is 2 cm, and the predetermined average flow rate is 1.0 mL / s.

4. The method for evaluating the water absorption and agglomeration performance of cat litter according to claim 1, wherein: The temperature of the cat litter is 20°C to 30°C.

5. The method for evaluating the water absorption and agglomeration performance of cat litter according to claim 1, wherein: The test solution is pure water, saline or urea saline, and the temperature of the test solution is 38.0°C to 39.5°C.

6. The method for evaluating the water absorption and agglomeration performance of cat litter according to claim 5, wherein: The test solution is pure water, and the temperature of the test solution is 38.0°C.

7. The method for evaluating the water absorption and agglomeration performance of cat litter according to claim 5, wherein: The pure water mentioned above refers to laboratory water that meets the third-grade water standard or above in GB / T 6682; the brine mentioned above refers to an aqueous solution containing 0.9% or 1% sodium chloride; the urea brine mentioned above refers to an aqueous solution containing 1% urea and 0.9% sodium chloride.

8. The method for evaluating the water absorption and agglomeration performance of cat litter according to any one of claims 1 to 7, wherein: The cat litter container is a transparent cat litter container; after the cat litter has completely absorbed the test solution, the cat litter is taken out to obtain cat litter condensed lumps.

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