JPS6073437A - Apparatus for atomizing sample for spectrochemical analysis - Google Patents

Abstract

PURPOSE:To make unnecessary a calibrating operation for analyzing a standard sample in the course of the analysis by preventing a variation of a particle diameter distribution of spray particles due to an atm. temp. in a sample sprayer. CONSTITUTION:A water jacket 11 is provided by surrounding an outer side of an outer circumferential wall 1 and a cylinder part 4, a warm water whose temp. is controlled to a fixed temp. somewhat higher than that of outer air is circulated therethrough, and halfway parts of a spraying air supplying tube 12 and a gas supplying tube 9 are passed through a warm water vessel 13. The warm water whose temp. is controlled fixedly is circulated through the vessel 13. By this constitution, the temp. in a spraying chamber A is held to a fixed temp. at a precision of + or -0.1 deg.C. If the temp. is controlled to the fixed value by circulating the warm water, heat capacity of the warm water is large, and a temp. ripple with an on-off control of a temp. controller can be made small.

Description

Detailed Description of the Invention A. Field of Industrial Application The present invention is applicable to analytical methods such as flame spectroscopy and atomic absorption spectrometry, which spectrally measure light emitted or absorbed by atomized sample component elements. This invention relates to a flame-type sample atomization device used for.

There are various methods for atomizing a sample in conventional optical emission spectrometry or atomic absorption spectrometry, but the method that is the subject of the present invention involves atomizing and introducing a sample solution into the flame of a gas burner. The sample is atomized using the high temperature of a gas flame, and the device for this purpose consists of a laminar flow type burner and a sample atomizer that atomizes the sample solution and introduces it into the burner. .

The method of sample atomization is the atomization method, in which the sample solution is sucked up by an air flow and sprayed into a spray chamber, where it is mixed with fuel gas and the large diameter ones are excluded, leaving only two small diameter ones. is sent into the gas flame. In this case, if the particle size distribution of the atomized particles in the atomizer 1 fluctuates, the amount of sample supplied to the gas flame will fluctuate, causing an error in the quantitative value in quantitative analysis. Therefore, it is important to stabilize the particle size distribution of mist particles, but in conventional equipment, the only means for achieving this is to provide a flow control valve for the atomizing air and fuel gas (propane, acetylene, etc.). .

Of course, the particle size distribution of the mist particles changes depending on the flow rate of the atomizing air and the flow rate of the fuel gas, which affects the time it takes for the mist particles to reach the gas flame, but the cause of the variation in the particle size distribution is temperature change. That is, since the particle size of the atomized sample solution particles decreases due to evaporation of water, as the outside temperature increases, the evaporation speeds up and the proportion of fine particles increases. However, conventional devices do not take into account changes in outside temperature. For this reason, when analysis is continued for a long time in an environment where the room temperature fluctuates, even if the same sample is analyzed, the analytical values may vary beyond the permissible limit. Therefore, in such cases, it was necessary to occasionally analyze the standard sample and check the changes in the analytical values. However, when a large number of samples must be analyzed within a given time,
The time spent performing the above-mentioned calibration analysis is also wasted. For example, when used in conjunction with a biochemical multi-item automatic analyzer that wants to obtain measurement results every 12 seconds, while calibration analysis is being performed, other devices must stop their analysis operations.

C. Objective The present invention aims to prevent changes in the particle size distribution of mist droplets in a sample atomizer due to outside temperature, thereby eliminating the need for a calibration operation in which a standard sample is analyzed during analysis.

2. Structure In order to achieve the above object, the present invention includes a temperature control means for keeping the outer wall surface of the spray chamber at a constant temperature, and a temperature control means for keeping the temperature constant during supply of the injection gas and fuel gas. The present invention provides a sample atomizer equipped with a sample atomizer.

E. Embodiment FIG. 1 shows an embodiment of the present invention. A is a spray chamber, and 1 is a cylinder on the outer peripheral wall of the spray chamber A. A burner tube 2 is inserted concentrically into the outer wall 1, and a burner cap 3 is attached to the upper end of the burner tube 2, so that a flame F is formed on the top of the burner cap 3. It has become. A cylindrical portion 4 is provided on the side surface of the outer circumferential wall l in a direction perpendicular to the axis of the outer circumferential wall, and a spray nozzle 5 is inserted concentrically into the cylindrical portion.

The spray nozzle consists of an outer tube 6 with a constricted opening end and a suction tube 7 inserted concentrically into the outer tube 6.
Atomizing air is supplied to the sample solution S at the rear end of the suction tube 7.
It is inserted inside. The circular tube portion 4 is provided with an opening 8 for ejecting fuel gas in a direction parallel to the spray nozzle 5, and the opening communicates with a fuel gas supply pipe 9. Reference numeral 10 denotes a mist finer, in which the mist droplets ejected from the nozzle 5 collide and are finely divided. The spray chamber A has a burner cylinder 2 inserted therein and constitutes a cyclone type dust collector, and the large-diameter and heavy particles in the mist droplets sprayed from the spray nozzle 5 hit the inner surface of the outer peripheral wall l and adhere. Then, they descend downward and are discharged from the funnel-shaped bottom B of the spray chamber, and the fine particles ride the flow of the mixed gas of fuel gas and spray air and rise inside the burner cylinder 2 and are supplied into the flame F. Ru.

A feature of the present invention is that a water jacket 11 is provided surrounding the outer peripheral wall 1 and the outside of the cylindrical portion 4 to circulate hot water whose temperature is adjusted to a constant temperature slightly higher than the outside air. A hot water tank 1 is placed in the middle of the gas supply pipe 9.
It is located in a place where 3 middle sections are allowed to pass through. The hot water tank 13 is designed to circulate hot water whose temperature is controlled to be constant. 1
4.15 are circulating hot water temperature controllers.

With the above-mentioned configuration, the temperature inside the spray chamber A is 10.

The temperature is maintained at a constant temperature with an accuracy of 1°C or less. When hot water is circulated and the temperature is controlled to be constant, the heat capacity of the hot water is large and it is easy to reduce the temperature ripple caused by on/off control of the temperature regulator.

In the above embodiments, a water jacket was used to maintain a constant temperature in the spray chamber, but an air bath may be used instead. Further, instead of the water jacket, a pipe may be wrapped around the outer surface of the outer peripheral wall 1 to flow hot water.

Effects According to the present invention, the analysis results of flame light analysis or atomic absorption spectrometry are stable even if the room temperature fluctuates, and therefore there is no need to perform calibration analysis using standard samples from time to time. Time efficiency in continuous analysis of a large number of samples is improved, and cooperation with other analyzers becomes easier when various analyzes are automatically executed at the same time in conjunction with other analyzers. In addition, if the eruption chamber, etc. is kept at a higher temperature than room temperature, the temperature control plate only needs to be turned on and off, and unlike the case where the temperature is maintained at a constant temperature near room temperature, both heating means and cooling means are not required. Easy to control. However, the present invention is not limited to the use of only a heating means, but may also be a combination of both heating and cooling means or a cooling means alone to maintain a constant temperature lower than room temperature.

Figure 2 shows the relative change in the measured value of Na concentration at a concentration of 140 mEj/V when the room temperature was changed from 25°C to 37°C using a conventional device. It has changed to .9. Figure 3 shows an embodiment of the present invention in which when the room temperature is changed from 28°C to 37°C, the temperature of the outer wall l of the spray chamber is from 38°C to 39.6°C.
The relative change in the measured value of Na concentration remains within 1 change from 100 to 102.1.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional side view of an apparatus according to an embodiment of the present invention, FIG.
FIG. 3 is a graph showing the effects of the present invention. 1... Outer peripheral wall of the spray chamber, 2... Burner tube, 5...
Spray nozzle, 7... Suction tube, S... Sample solution, 9.
...Fuel gas supply pipe, 11...Water jacket,
12... Air supply pipe for spraying, 13... Hot water tank, 14
．． 15... Circulating hot water temperature controller. Figure 2

Claims (1)

[Claims] For spectroscopic analysis, consisting of a gas burner equipped with a sample atomizer, which has a temperature control means for keeping the outer peripheral wall of the spray chamber at a constant temperature, and a temperature control means for keeping the temperature constant during supply of the atomization gas and fuel gas. Sample atomization device.