JPS6391540A - Method and apparatus fluorescent x-ray analysis - Google Patents

Abstract

PURPOSE:To enhance the accuracy of a measured value, by providing a rotary blade self-propelling by a supply stream in a specimen holder and performing analysis while a slurry is stirred by said rotary blade. CONSTITUTION:A specimen holder is constituted by screwing frame lid 8 to the upper surface of a holder main body 3 and subsequently engaging the lower part of said main body 9 in a united state. The specimen in a tank 10 is guided to the specimen inflow pipe 1 of the holder main 3 through a tank 12 while stirred by a pump 11 and refluxed to the tank 10 through an outflow pipe 2. The holder main body 3 is formed into a shallow circular container shape, and the inflow pipe 1 and the outflow pipe 2 are arranged to the peripheral wall of said holder main body 3 in an almost tangential direction and a rotary blade 13 is provided in the main body 3 in a freely rotatable manner. When a slurry like specimen is continuously supplied in the specimen holder and recirculated, the inflow specimen allows the rotary blade 13 to rotate and is sent between vanes under pressure to be discharged toward the outflow pipe 2.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a method and apparatus for direct fluorescent X-ray analysis of a sample in the form of a slurry, and in particular to a method and apparatus for directly analyzing a sample in the form of a slurry. The slurry is made uniform by providing the slurry.

Conventional method Fluorescence X-ray analysis is a compositional analysis method widely used in the field of powder metals and metals, in which a given sample is wet-pulverized with an appropriate solvent using a ball mill, etc., and the solvent is removed to form a powder. It is common to apply it to an analyzer in the form of powder, or in the form of a mixture of vitrification agents and a fixed mixture. However, removing the solvent and analyzing the powder form is
It takes a long time to remove the solvent and dry it, and analyzing it after fixing it by vitrification is inconvenient, such as making sample preparation complicated, so recently samples obtained in slurry form are being analyzed as they are. A method is being tried. However, this method works well if the specific gravity of each component contained in the sample is similar, but if the sample contains components with different specific gravity, the distribution of the components in the upper and lower phases of the slurry will change over time due to the difference in specific gravity. In other words, over time, the heavier objects settle to the bottom, and when X-rays are applied from above, the X-ray intensity of the heavier objects decreases, so the appearance is higher, as if the proportion of heavy objects is small. This will inevitably lead to inaccurate measurement results. Taking this point into consideration, the inventor previously developed a method to prevent sedimentation of high specific gravity components by continuously circulating the slurry sample in the sample holder through a separately provided stirring chamber (VF application). (No. 61-69486), this method is also not always satisfactory because the slurry is not sufficiently homogenized compared to the original powder method and vitrification method.

Problems to be Solved by the Invention As mentioned above, in the above method of forcibly circulating a sample through a pump, the sample holder is made thin enough to prevent X-rays from passing through, and the flow of the sample is made into a thin layer. Even if I get close,
In areas other than the straight line connecting the inlet and outlet of the sample holder, the flow velocity inevitably decreases and it is difficult to keep the slurry sufficiently uniform.If this point is not resolved,
It was found that no more accurate measurements could be made. An object of the present invention is to provide a method and apparatus for achieving uniformity of slurry within such a sample holder and improving the accuracy of measurement values.

Means to Solve the Problem The inventors conducted various research on ways to homogenize the slurry in the sample holder and improve measurement accuracy, and as a result, they installed rotary blades that are self-propelled by the supply flow inside the sample holder. death,
It was discovered that the objective could be achieved by analyzing the slurry while stirring it, and based on this knowledge, the present invention was completed.

In other words, the present invention enables a slurry sample to be liquid-tightly irradiated with X-rays to analyze the composition of a substance by measuring the intensity of fluorescent X-rays generated from each element in the sample. In addition to continuously supplying and circulating the sample inside the sample holder, which has a circular inner circumferential surface, a rotating blade is provided that moves by itself due to the flow of the sample supplied within the sample holder. The present invention provides a fluorescence XIQ analysis method for homogenizing a sample by stirring and an apparatus used therefor.

In this way, in this invention, the sample holder is shaped like a shallow box with a circular plane in order to make the flow of the sample not just a free flow flowing in a constant force direction but a forced flow that always occurs over the entire area inside the sample holder. At the same time, a rotor is provided close to the inner surface of the rotor to partition this circular shape, and the rotor has a structure in which the movement of the closed space is carried out by the fluid itself flowing from the inlet to the outlet rather than by external power. In other words, the sample is self-propelled and circulated using the same principle as the internal movable member in a positive displacement motor, and the sample flowing into the closed space from the inlet is energized by the flow energy in that space. This will lead to further homogenization.

Next, an embodiment of the apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a side sectional view of a sample holder, which is the main part of the present invention, and these are clearly shown in FIG. 2. On the upper surface of the holder main body 3, which is shaped like a circular shallow container, has a sample inlet tube 1 and a sample outlet tube 2 at approximately diametrical positions on the circumferential surface.
Ring 4, Mylar 5 made of polypropylene film
, a rubber packing 6 and a net 7 are placed thereon, and after the frame gap 8 is screwed together, the lower part of the holder main body 3 is fitted to the base body 9 to form an integral structure, as shown in FIG. 3. The sample in tank 10 is stirred by pump 11 and transferred to tank 1.
2 to the sample inlet tube 1 of the holder main body 3, and then returns to the sample storage tank 10 through the sample outlet tube 2. As described above, the holder main body 3 is formed in the shape of a shallow circular container, and as shown in FIGS. 4 and 5, the holder main body 3 extends through the peripheral wall and is located approximately tangentially to the inner peripheral surface, and has a sample inlet tube 1 and a sample outlet tube. A tube 2 is disposed, and one rotary blade 13 is rotatably provided inside the tube 2 with each blade tip close to the inner circumferential surface and pivotally supported on the bottom surface of the center. This rotor blade 13 consists of six blades, each blade tip is bent at an angle of approximately 40 degrees to one side to form a receiving surface 14, and the center part is supported by a needle bearing etc. so that it rotates extremely lightly. It is now possible to do so. The rotor blade is preferably made of a material that does not affect the measured elements and can be used to analyze many types of substances, and in this case it is made of copper.

Effects of the Invention As described above, the present invention continuously supplies and circulates a slurry sample into a liquid-tight sample holder, and also tangentially inflows the sample from the sample inflow pipe 1 into the sample holder. A rotary blade 13 is provided with each blade tip positioned close to the inner circumferential surface of the holder, and this inflowing sample rotates the rotor blade 13, and this rotation causes the sample present between adjacent blades to The configuration is such that the sample is directly pushed and discharged toward the sample outflow tube 2, and as described above, movement is performed in a closed space similar to that of a positive displacement pump, so the movement of the sample in the sample holder is even and extremely efficient. Analysis can be performed.

As a result of experiments conducted using the above-mentioned apparatus, results closer to those of the powder method and the vitrification method can be obtained compared to the above-described sample holder which does not have a rotary blade but simply has an inlet/outlet tube.

Example Next, the present invention will be explained in more detail with reference to Examples.

Example In the device shown in Fig. 1, the inner diameter of the main body of the holder is 43xx.
, a depth of 12.5 mm, an inflow pipe and an outflow pipe diameter of 5 u, a rotor diameter of 40.5 JIJ, and a height of 10 Iz, and a sample powder containing iron and strontium was analyzed.

The results are shown in the table below.

For comparison, the results measured using a sample holder without rotary blades and the results obtained using the conventional powder method and vitrification method are also shown.

As is clear from this table, the measurement error (σ) according to the method of this invention is significantly improved compared to the case where no rotary blade is used, and the accuracy is comparable to that of the powder method and the vitrification method.

[Brief explanation of the drawing]

The drawings show the main parts of the apparatus according to the present invention, and Fig. 1 is a side sectional view of the sample holder, Fig. 2 is an exploded side view of each part of Fig. 1, and Fig. 3 is a sample circulation system. FIG. 4 is a partially sectional side view of the main body of the holder, and FIG. 5 is a plan sectional view. In the figure, reference numeral 1 indicates a sample inflow pipe, 2 a sample outflow pipe, 3 a holder main body, 10 a sample storage tank, 11 a pump, 12 a stirring tank, and 13 a rotating blade. Patent applicant TDC Co., Ltd. Agent
Same shape Figure 1 Figure 2 Figure 4 Figure 5

Claims (1)

[Claims] 1. When analyzing a substance by irradiating a predetermined sample with X-rays and measuring the intensity of fluorescent X-rays generated from each element in the sample, the slurry sample is liquid-tightly While continuously supplying and circulating the sample holder with a circular inner peripheral surface,
A fluorescent X-ray analysis method characterized by providing a rotary blade that is self-propelled by the flow of a sample supplied in a sample holder, and thereby forcibly stirring the sample in the sample holder to homogenize the sample. 2. In a fluorescent X-ray analyzer that uses a slurry sample, a sample holder that is liquid-tight and has a sample inflow pipe and a sample outflow pipe is connected to a stirring tank via a pump and a circulation pipe, and The holder has a circular inner circumferential surface and one rotary blade that rotates with each blade tip close to the inner circumferential surface, and the center line of the sample inlet tube coincides with the center of rotation of the rotary blade. A device characterized in that it is opened in a direction in which it does not move.