JP2005098813A - Apparatus and method for performing in-situ and instantaneous measurement on characteristics of liquid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and a method for performing in-situ measurement, on at least one of the characteristics of a liquid housed in a container. <P>SOLUTION: The apparatus for measuring at least one of the characteristics of the liquid below a surface comprises (a) a housing having a front end; (b) at least one probe assembly at the front end of the housing comprising an inert gas generating means, comprising an inert gas source, conduit for guiding an inert gas to the front end of the housing, and a means for moving a downstream-side flow from the inert gas source and a stable volume of the inert gas to the front end of the housing and the interface of the liquid and the probe assembly to any depth or angle in the liquid; (c) a radial beam assembly, comprising both a means for generating a radial beam sufficient for vaporizing a part of the liquid into a species to be detected and a means for transmitting the radial beam to the interface between the liquid and the stable volume of inert gas through the front end of the housing; (d) and a detection means for receiving the species to be detected and detecting at least one of the characteristics of the liquid, on the basis of the species to be detected. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates generally to an apparatus and method for instantaneously measuring the properties of a liquid, such as a molten metal, in situ.
The liquid can also be stationary or flowing. Immediate measurements can be taken from any location including the interior of the liquid and the surface of the liquid.
When the measurement is performed below the surface of the liquid, a stable amount of inert gas under a continuous flow allows a rapid and accurate passage of the radiation beam into the liquid to generate the detection species Provided at the interface of the liquid and device and analyzed to determine the desired properties.
Alternatively, the device can be operated in a stationary mode that does not emit any radiation by detecting species originating from the liquid.

The measurement of various properties of liquids, including but not limited to quantitative and qualitative measurements of concentration and formulation, is very important in various industrial applications.
When liquid is contained in a container, measurements can be taken periodically by obtaining a sample of the liquid and transporting the sample to a remote location, such as a laboratory.
Quantitative and qualitative measurements are made in the laboratory and then returned to the container operator to determine whether adjustments to the liquid formulation should be made.
Measurements that measure liquid concentration and formulation are known, but the time to make such measurements and communicate information to the container operator is a problem in metal production (eg, steel or aluminum production).

As an example, tightly controlling the formulation during steel production is important for the production of high quality products. Ironworks operators are obliged to make fine adjustments to the melted metal mix.
Currently, molten metal samples are removed from the furnace and sent to a laboratory where spectroscopic measurements are made to determine the composition of the steel components.
The analysis results are returned to the furnace operator to determine if the actual composition of the molten metal is desirable.
If not desired, the formulation is adjusted by adjusting the relevant melted metal components.

Since it takes time to finish the composition analysis of the dissolved product, there is a problem in the production rate of a desired product (for example, steel).
It is desirable to use an apparatus and method for in-situ analysis of liquids such as molten metal and molten glass so that adjustment of the liquid formulation is made in a shorter time than using an external laboratory.
One such approach is disclosed by Karlhof et al., US Pat. No. 4,995,723 and related US Pat. No. 4,993,834, referenced herein by reference.
These references disclose a method for analyzing molten metal elements by providing a conduit that is stationary on the side of the container containing the molten metal.
The laser beam is directed into the conduit and to the surface of the molten metal. Light is generated by the plasma formed by the interaction of the laser beam, and the molten metal combines with the light guide plate through the lens system and is passed by the light guide plate to the spectrometer 157.
The system provides a measurement of molten metal only on the surface and takes a measurement in place because the conduit is in a fixed position.

Other fixed conduit systems are disclosed in US Pat. Nos. 5,830,407 and 6,071,466 by Kate, which are incorporated herein by reference. The fixed conduit is inserted into the bottom of the container containing the molten metal. The central pipe of the fixed conduit carries clear gas under pressure that maintains the opening in the molten metal.
The gas flow has a sufficient hydrostatic head to prevent molten metal from entering the conduit. The inspection window assembly allows direct viewing of the molten metal and an optical sensing device such as a photometer or spectrometer 157 is used to determine the melted metal formulation.
Melted metal measurements are made only at one fixed location within the molten metal.

There are a number of disadvantages to the system described above. These prior art systems use a fixed conduit in which all measurements must be made from either a fixed position on the surface of the molten metal or at one location within the molten metal.
Such a system is disadvantageous because the molten metal composition may change during compounding in a single container.
The accuracy used in adjusting the melted metal formulation depends on a partial high accuracy reading of the overall solution bath formulation.
As referenced above, if only one fixed location is provided for analysis, the accuracy of the analysis of the entire molten metal is compromised.

Further, the disadvantages of the prior art described above relate to the angle at which the instrument interacts with the probe. Because molten metal is denser than gas, the device disclosed by Karl Hof et al. Cannot maintain a stable bubble of gas for making measurements.
The heavier melted raw material flows in holes in the furnace wall, replacing any gas. Thus, the gas flows continuously to maintain the melted raw material outside the instrument.
This continuous flow creates a non-stationary interface between the gas and the melted raw material, making the most accurate measurement process very complicated when the interface is stationary so as to be optically focused.
A constant pressure is required to maintain the melted raw material outside the device, for example, loss of gas pressure due to leaks in the gas supply line adversely affects the desired measurement and damages the instrument .

The device disclosed by Kate has similar disadvantages. The vertical direction can maintain a stationary surface, but if pressure is lost, the device is destroyed and the melted raw material is lost, as in the invention of Karl Hof et al.
Also, in the case of Kate's invention, the vertical column of gas is stationary, but it is particularly unstable if the gas is released into the tank due to a sufficiently large blockage and the remainder of the gas may flow. High and melted raw material flows into the tube.

A further disadvantage of Kate's invention relates to the approach required from the bottom of the furnace. Access to the bottom of a commercial furnace is typically very difficult due to the weight of the furnace.
There is a potential for a leak of melted raw material to the floor where the workers are located along with the port located at the bottom of the furnace. If the port is on one side, the material leaks out until the melted raw material height in the container drops below the port height.
Nearly all the volume of molten metal contained in the furnace, with the port and gas located at the bottom of the vessel and with a column extending only a short distance into the furnace, will leak if there is a loss of gas pressure There are things to do.

Another disadvantage of systems such as Kate and Karl Hof relates to where the analysis is performed. The invention of Karl Hof et al. Takes a sample of molten raw material on the side of the furnace, and the invention of Kate takes a sample of molten raw material near the bottom of the furnace. These locations may contain melted raw materials that are not representative of the entire bath.
When the furnace operator introduces the alloying element into the vessel, the operator attempts to mix the alloying element so that it is well distributed within the vessel.
However, when it is difficult to introduce mechanical agitation, it is most difficult to reliably bring the alloying element close to the side of the furnace through mixing of raw materials.
If alloying elements diffuse throughout the bath, it takes the longest time for the alloying elements to reach the sides. If melting takes place before diffusion is complete, taking a sample near the side does not represent the entire bath.
In the case of molten glass, there is also a large amount of thermally generated flow, such as a flow of hot material rising like a pocket and a downward flow of cold material.
These upward and downward flows tend to prevent uniform melting or make uniform melting more difficult.

Another method for quantitative and qualitative measurement of metals uses a laser-induced breakdown spectroscopy (LIBS) system. Such a system is usually for immediate spectroscopic analysis of raw materials in situ through employing a laser pulse with sufficient power to irradiate a representative amount of a heterogeneous sample at an intensity that produces a plasma. Equipment.
The plasma is composed of a small amount of material that is vaporized and ionized by a laser pulse. In the plasma, the molecules of the material are separated and the atoms are excited to a charged state. As the plasma is cooled, charged atoms (ions) emit wavelength electromagnetic waves, especially at specific elemental atoms in wavelength.
By observing the electromagnetic radiation with a spectrometer 157 capable of resolving different wavelengths, the elements in the emitted sample can be identified.
The intensity of the radiation can be quantified and compared through calculations with reference samples and / or various atomic constants to confirm the concentration of elemental atoms in the material.

An example of such a system used to analyze solid samples is disclosed in US Pat. Nos. 5,781,289 and 6,008,896 by Sub-Sabi et al.
Avinson, in US Pat. No. 5,664,401, applies the LIBS system to the melted raw material gas, infers the melt mix from the measured mix of gas, and analyzes the melted metal.
Shin et al., US Pat. No. 5,751,416, describes a method for analyzing liquid material directly using the LIBS system only on the surface of the liquid. Each of the above references is incorporated herein by reference.

Kim U.S. Pat. No. 4,986,658, incorporated herein by reference, describes a method for analyzing melted raw materials under the surface of the lysate using a LIBS system.
The design of the reference invention has a number of drawbacks. First, an expensive assembly of devices (ie, spectrometer 157 and laser 50) is provided in close proximity to the furnace. In the event of an accident where these assemblies fall into the furnace or come into contact with molten metal, or the assemblies are exposed to temperatures exceeding acceptable limits (eg, cooling system failure), the investment in equipment is a loss. Become.
This risk complicates the design of the referenced invention and requires the use of heat shields and cooling systems. This complexity increases the cost of the system, increases the number of subsystems that can be damaged, and potentially leads to equipment loss.
The probe is also limited to a few centimeters below the surface of the lysate to release any floating slag.
Also, the system cannot be submerged to any sensitive range in the furnace.

Another important aspect of the reference design is the limited number of locations from which the lysate is sampled. Since the placement of the spectrometer 157 and laser 50 is just above the melted raw material, the referenced US Pat. No. 4,986,658 extends the outside of the probe to change the focal length of the optical assembly. In fact, it is not possible to scrutinize deeper places of the lysate without substantially changing the design.
Also, the probe cannot be inserted at an angle other than vertical, further limiting the applicability of the furnace design to access from the top of the furnace.
As mentioned above, taking samples of raw material melted at a plurality of locations is substantially better for analysis of the lysate.

  Another disadvantage of the apparatus of US Pat. No. 4,986,658 is that it prevents the placement of multiple probes throughout the metal manufacturing facility. By coupling the laser and spectrometer 157 to the probe housing, placing multiple probes forces the plant operator to purchase many lasers and spectrometers and is very expensive.

The reference device is further disadvantageous because the inert gas does not flow into the melted raw material. There are two advantages to flowing an inert gas through a molten raw material. First, the inert gas can locally agitate the lysate so that the laser pulse does not analyze the same raw material. The inert gas stream can then remove contaminants from the inside of the melted raw material. This happens in two ways. Undesirable gases dissolved in the lysate are mixed with an inert gas so as to rise and are therefore removed from the lysate.
Also, pollutants that normally float and are scooped up are bubbled and otherwise rise faster.
The practice of using an inert gas to remove contaminants is known to those skilled in the art.

Thus, if the liquid is stationary, flows and moves, at least one property of the liquid can be measured so that the device can quickly take a sample in the liquid or at multiple locations on the surface If an apparatus is provided, it is a significant advance in the technology that performs immediate in-situ measurement of liquids.
It is a further significant advance in the art to provide a device that can be inserted into the liquid at different angles to the surface of the liquid and that will not suffer any loss of the liquid or the assembly of the device if the system fails. .

  It is a further advancement in the art to provide an apparatus and method for using a relatively expensive configuration (eg, a laser), eliminating unnecessary duplication of the configuration, and making more efficient measurements.

  The device is submerged under the surface of the liquid, and the supply of inert gas to the liquid a) purifies the liquid, b) stirs the liquid so that more representative samples of the liquid are analyzed, c) It is a further advancement in the art to provide an apparatus and method for performing measurements that assists in preventing measurement interference by not creating gas bubbles in the liquid that interfere with sensor operation.

U.S. Pat. No. 4,986,658

(Summary of the Invention)
The present invention relates generally to devices and methods for making in-situ and / or quantitative and qualitative measurements of the properties of a liquid, such as, for example, a molten metal. The liquid is stationary or flowing. The present invention is capable of performing such measurements from any location within and within the liquid surface.

The invention according to claim 1 includes: a) a housing having a front end; b) an inert gas generating means comprising an inert gas source; a conduit for guiding the inert gas to the front end of the housing; and a lower side from the inert gas source. At least one probe at the front end of the housing, comprising a flow of gas, a stable volume of inert gas, a boundary between the front end of the housing and the liquid interface and a means for moving the probe assembly to any depth or angle in the liquid An interface between the assembly and c) means for generating a radiation beam sufficient to vaporize a portion of the liquid into the detection species, and the radiation beam through the front end of the housing and the liquid and a stable volume of inert gas. A radiation beam assembly comprising means for delivering to the detector, and d) detection for receiving the detection species and detecting at least one property of the liquid from the detection species A device for measuring at least one property of the liquid below the surface consisting of the stage.
The invention according to claim 2 relates to the apparatus of claim 1, characterized in that the inert gas generating means further comprises means for generating a continuous flow of inert gas to the front end of the housing.
The invention according to claim 3 relates to the apparatus according to claim 1, characterized in that the means for generating the radiation beam are arranged outside the housing.
The invention according to claim 4 relates to the apparatus of claim 1, characterized in that the means for generating the radiation beam are arranged inside the housing.
The invention according to claim 5 relates to the apparatus of claim 1 comprising a plurality of probe assemblies.
The invention according to claim 6 relates to the apparatus according to claim 1, characterized in that at least one probe assembly is arranged in the liquid.
The invention according to claim 7 relates to the apparatus of claim 1, characterized in that the at least one probe assembly is arranged at a surface of the liquid or at a position beyond the surface.
The invention according to claim 8 relates to the apparatus according to claim 1, wherein the raw material is a material in which a liquid is dissolved.
The invention according to claim 9 relates to the apparatus according to claim 1, wherein the liquid is a molten metal or molten glass.
The invention according to claim 10 relates to the apparatus of claim 1 wherein the radiation beam assembly comprises means for forming a radiation beam comprising at least one wavelength from the electromagnetic spectrum.
The invention according to claim 11 relates to the apparatus according to claim 10, characterized in that at least one wavelength is selected from the group consisting of X-rays, ultraviolet rays, radio waves, infrared rays and microwaves.
The invention according to claim 12 relates to the apparatus of claim 1, wherein the radiation beam is a laser beam.
The invention according to claim 13 relates to the apparatus of claim 1, wherein the radiation beam is a sound beam.
The invention according to claim 14 relates to the apparatus according to claim 1, wherein the detecting means is a spectrometer 157.
The invention according to claim 15 relates to the apparatus according to claim 1, characterized in that the detection means is a radiometer.
The invention according to claim 16 relates to the apparatus of claim 12, comprising a laser-induced breakdown spectroscopy system.
The invention according to claim 17 is characterized in that the front end of the housing comprises a nozzle assembly, the nozzle assembly being in contact with the liquid and at least one first opening that allows the inert gas to contact the liquid. 2. The apparatus of claim 1 comprising pressure control means for maintaining the inert gas at a stable capacity.
The invention according to claim 18 relates to the apparatus according to claim 17, wherein the pressure control means comprises at least one channel for moving the inert gas away from the interface between the housing and the liquid.
The invention according to claim 19 is characterized in that the channel has a first opening for receiving an inert gas and at least one first opening when the device is operatively located to determine the characteristic. The apparatus according to claim 18, comprising a second opening located above the portion.
The invention according to claim 20 relates to the apparatus according to claim 17, further comprising temperature control means for controlling the temperature in the apparatus.
The invention according to claim 21 is characterized in that the temperature control means further comprises a second flow of gas or liquid in close proximity but not in contact with a stable volume of inert gas. It relates to 20 devices.
The invention according to claim 22 relates to the apparatus according to claim 19, characterized in that the second opening is located below the surface of the liquid.
The invention according to claim 23 relates to the apparatus according to claim 19, wherein the second opening is located above the surface of the liquid.
The invention according to claim 24 further comprises surplus gas discharge means for removing excess gas from the gas used to form a stable volume of inert gas. About.
The invention according to claim 25 relates to the apparatus of claim 1, wherein the means for generating the inert gas further comprises a plurality of conduits for sending a plurality of inert gas streams to the interface.
The invention according to claim 26 includes a liquid in the container, the container being angled relative to the longitudinal axis of the container to allow a probe assembly to be inserted into the side wall of the container. 2. The apparatus of claim 1 having a front end of the housing configured to form [theta].
The invention according to claim 27 relates to the apparatus of claim 26, characterized in that said angle θ is approximately 45 degrees.
The invention according to claim 28 relates to the apparatus of claim 1, further comprising an interface detection assembly for detecting the surface of the liquid at the stable volume interface of the liquid and inert gas.
The invention according to claim 29 is characterized in that the interface detection assembly further includes electrical circuit means at the front end of the housing, and forms an electrical circuit when the electrical circuit means contacts the surface of the liquid. The present invention relates to 28 devices.
The invention according to claim 30 relates to the apparatus according to claim 29, wherein the liquid is an electrically conductive liquid.
The invention according to claim 31 relates to the apparatus according to claim 1, wherein the liquid is flowing.
The invention according to claim 32 relates to the apparatus of claim 31, characterized in that at least one probe assembly is arranged above the surface of the fluid in liquid state.
33. The invention according to claim 33 for measuring at least one characteristic of a liquid at the surface of the liquid, wherein the at least one probe assembly is fixed and suspended above the liquid. Relates to the device.
The invention according to claim 34 relates to the apparatus according to claim 1, comprising a plurality of probe assemblies.
The invention according to claim 35 relates to the apparatus of claim 33, wherein the plurality of probe assemblies are arranged at different positions in the container containing the liquid.
The invention according to claim 36 relates to the apparatus according to claim 34, wherein a plurality of probe assemblies are arranged in the container at different depths.
The invention of claim 37 relates to the apparatus of claim 33, wherein the plurality of probe assemblies are operatively connected to a few radiation beam assemblies.
The invention according to claim 38 relates to the apparatus according to claim 36, wherein a plurality of probe assemblies are connected to a single radiation beam assembly.
The invention according to claim 39 relates to the apparatus according to claim 33, characterized in that a plurality of probe assemblies are connected to a smaller number of sensing means.
The invention according to claim 40 relates to the apparatus according to claim 39, wherein a plurality of probe assemblies are connected to a single sensing means.
The invention according to claim 41 relates to an apparatus according to claim 12, comprising an optical cavity for transmitting the laser beam to the liquid for the sensing means and to the detection species from the liquid.
The invention according to claim 42 relates to the apparatus according to claim 1, characterized in that the radiation beam assembly is an arc discharger.
The invention according to claim 43 comprises an electrode disposed away from the liquid and electrically connected to the arc discharger, and the arc is generated from the electrode by the arc discharger to generate a detection species from the liquid. 43. The apparatus of claim 42, wherein the apparatus generates sufficient electrical energy to move to the liquid.
44. The invention according to claim 44 wherein the radiation beam assembly comprises a method for delivering a plurality of radiation pulses to a stable interface in a method for enhancing a signal to a noise ratio. Relates to the device.
The invention according to claim 45 relates to the apparatus according to claim 43, characterized in that the radiation beam pulses are collinear.
The invention according to claim 46 relates to the apparatus according to claim 16, further comprising a sensor for measuring a sound wave signal generated from the laser induced breakdown spectroscopy system.
The invention according to claim 47 relates to an apparatus according to claim 1, characterized in that the radiation beam assembly comprises an ultrasonic beam assembly characterized in that the properties of the liquid to be measured include density and flow rate.
The invention according to claim 48 comprises: a. A housing having a front end; b. A probe assembly at a front end of at least one housing, the probe assembly comprising means for moving the probe assembly to any depth or angle of the liquid; c. A radiation beam comprising means for generating sufficient beam radiation to volatilize a portion of the liquid into the detection species and means for transmitting the radiation beam through the front end of the housing to the interface between the liquid and a stable amount of inert gas. An assembly; d. The present invention relates to an apparatus for measuring at least one characteristic at or below the surface of a liquid comprising a detection means for receiving a detection species and detecting at least one liquid characteristic from the detection species.
49. The invention according to claim 49, further comprising a protective wall between the radiation beam assembly and the liquid, the protective wall being capable of allowing the radiation beam to pass therethrough for generating the detection species. Relating to the device.
The invention according to claim 50, wherein at least one probe assembly is directed to the first portion of liquid contained in the container and at least one other probe assembly is flowing next portion of the liquid. The device of claim 5, wherein
The invention according to claim 51 is: a. A housing having a front end; b. A probe assembly at the front end of at least one housing, comprising an inert gas source and a conduit that directs the inert gas to the front end of the housing, under the flow from the inert gas source, the boundary between the front end of the housing and the liquid Said probe assembly comprising an inert gas means for providing a stable amount of inert gas to a surface and moving the probe assembly to any liquid depth or angle; c. A radiation beam comprising means for generating sufficient beam radiation to volatilize a portion of the liquid into the detection species and means for transmitting the radiation beam through the front end of the housing to the interface between the liquid and a stable amount of inert gas. An assembly; d. Installing at least one device comprising a detection means for receiving a detection species and detecting at least one liquid property from said detection species; and measuring at least one liquid property from two detection species The method relates to a method for measuring properties of at least one liquid at or below the surface.

  When subsurface liquids are used, a stable volume of inert gas under continuous flow produces a detection species that allows rapid and accurate passage of the radiation beam through the liquid to be analyzed to determine the desired properties. The device and liquid are provided at the interface to enable.

  Instead of a stable volume of inert gas, the device can use a window as a barrier to the liquid entering the device. Instead, the device is stationary and can detect species originating from the liquid without any radiation supplied by the device.

As one aspect of the present invention, the present invention provides:
a) a housing having a front end;
b) Inert gas generating means comprising an inert gas source, a conduit for leading the inert gas to the front end of the housing, and a lower flow from the inert gas source, providing a stable volume of inert gas to the front end of the housing and liquid At least one probe assembly at the front end of the housing, comprising means for providing at the interface of
c) means for generating a radiation beam sufficient to vaporize a portion of the liquid to the detection species and for sending the radiation beam through the front end of the housing to the interface between the liquid and a stable volume of inert gas. A radiation beam assembly comprising means;
d) detection means for receiving the detection species and detecting at least one characteristic of the liquid from the detection species;
An apparatus for measuring at least one characteristic of a subsurface liquid comprising:

  Methods for measuring liquid properties at or below the surface of the liquid using the apparatus are encompassed by the present invention.

  In another aspect of the invention, a window is provided at the end of the probe assembly to which the laser beam is sent, so that there is a need to provide a stable volume of inert gas at the interface where the liquid is analyzed. Exclude.

The following drawings, in which reference numerals indicate assemblies, illustrate embodiments of the invention and do not limit the invention as encompassed by the claims that form part of the application.
The present invention relates to a device for immediately analyzing and measuring in situ at least one property of a liquid that is stationary in a container or that flows out of the container, such as a molten metal.
As used herein, the term “liquid” refers to any type of liquid, and may be a transparent liquid or an opaque liquid, and the temperature of the liquid is not particularly limited. Such liquids include, but are not limited to, melted raw materials such as melted metals and melted glass, as well as solutions, diluents, emulsions, and the like.
The present invention provides a probe assembly that can obtain analysis and measurements from the surface of the liquid or from anywhere within the liquid, since the probe assembly can be immersed in the liquid. .

Since the apparatus of the present invention can be provided in a movable state, it can be quickly moved from one position to another, and spatially dispersed measurement values can be obtained in a short time. Such liquid properties can be determined, but is not limited to these properties. These characteristics cannot be obtained with the same speed and accuracy as the device of the present invention using typical conventional devices lacking mobility.
In certain embodiments of the invention, as described in detail below, the apparatus has a probe assembly that can simultaneously obtain measurements of one or two surfaces and / or complementary surfaces.
When submerged in a liquid, the device of the present invention uses a stable interface between the probe assembly and the liquid via a relatively cool inert gas supply. The supply of cold gas controls the temperature of the device, thereby transmitting and / or generating and / or generating and / or detecting a liquid detection species for analysis without damage to the radiation beam transmission assembly used to detect it. Enables immediate liquid analysis in situ.

The stable interface between the probe assembly and the liquid is a stable volume created by an inert gas flow, typically a continuous flow and a pressure control assembly that ensures the stability of the volume of gas at the interface. Is an inert gas. Devices and methods that employ this embodiment of the present invention may be detrimental to the ability of the configuration to generate and / or detect detection species from the liquids and their components due to the proximity of the liquids. Guarantee not to receive. This is an important advantage when the liquid is a molten metal.
This protection is facilitated because a stable volume of gas, preferably continuously supplied, is formed from a relatively cold gas supply. In this way, the gas is free from extreme temperatures due to its proximity to the molten metal. Furthermore, as the gas temperature rises, the gas is removed from the system and replaced with cold gas, so the temperature of the entire gas in close proximity to the temperature sensitive configuration of the device is below the damage limit. As a result, the configuration of the device is protected from damage and ensures correct operation.

A further advantage of using the inert gas described above becomes apparent when the device is immersed just below the liquid surface to analyze the liquid to be examined.
As the device is submerged in liquid, the pressure of the liquid at the tip of the device where the measurement is taken increases. If the gas flow is maintained, there is sufficient pressure to prevent molten metal from entering the probe assembly, and the stable interface position is maintained at a constant volume. In contrast, if raw gas bubbles are used and the gas pressure is not increased properly, the melted raw material can easily enter the device.
Similarly, when the probe assembly rises in the liquid and the hydraulic pressure at the tip of the probe assembly drops, the high pressure gas in the immobile foam can escape from the probe assembly, and the melted raw material It can penetrate the probe assembly and cause damage. The gas flow used in the present invention compensates for pressure changes and prevents damage to the device.

In order to overcome the disadvantages of the prior art, one embodiment of the present invention relates to an apparatus and method for analyzing liquids containing molten raw materials such as molten metal and molten glass. Yes. A stable interface between the probe assembly and the liquid is provided so that the radiation beam used to generate the detection species is not distorted by losing focus, and thus a rapid and accurate analysis of the detection species produced thereby Is possible.
The present invention also provides rapid measurements at multiple locations, such as making multiple measurements at the same time. As a result of the present invention, an overview of at least one property of the liquid, such as composition, concentration, etc., can inevitably be produced throughout the liquid, and changes over time can also be continuously monitored. However, it is not limited to these characteristics.
Thanks to the improvements of the present invention, it is now possible to measure not only the stationary liquid in the container but also the flowing liquid, and the present invention is suitable for industries such as producing metal and glass from molten raw materials. It has important impacts in various industrial fields.

  With reference to the drawings, referring first to FIGS. 2 and 3, an embodiment of the present invention for detecting at least one characteristic of a liquid contained in a container in a stationary or flowable state is shown. In particular, as shown in FIG. 2, a probe assembly 2 of the present invention is provided that comprises a housing 4 having a rear end 6 and a front end 8. As will be described later, in this embodiment of the invention, the front end 8 forms a stable interface with the liquid.

  Alternatively, the present invention may employ a window 9 in the opening at the front end of the device, instead of a stable gas-liquid interface as specifically shown in FIG. This configuration may be employed in embodiments as shown in FIGS. 13, 24, 25 and 27, as will be described later.

Included in the housing 4 is a radiation beam assembly 10. The radiation beam assembly 10 may be a laser beam transmitter and / or focus assembly such as a LIBS system (see prior art FIG. 1), an acoustic beam transmitter and / or a focus assembly (including an ultrasonic beam). , See FIG. 13), another type of assembly that can emit and / or focus, such as electromagnetic radiation (eg, x-ray, see FIG. 24) from various parts of the spectrum.
The assembly 10 receives a radiation beam from a location inside or outside the housing 4 (the outside of the housing is shown in FIG. 2) via a suitable cable assembly 11 and, if present, liquid- A beam of radiation is transmitted to the gas interface and, if necessary, the beam is illuminated or focused to produce a detection species for measuring at least one property of the liquid.
The radiation emanating from the detection species is collected by the radiation beam assembly 10 and transmitted from the probe assembly 2 to a device for performing liquid analysis, generally indicated at 13 and described in detail below. The

  Alternatively, the present invention may operate in a manner that does not transmit any radiation, but instead only collects data as described above and later in detail in connection with FIG.

  Alternatively, the radiation beam assembly 10 for generating, transmitting, collecting and / or focusing radiation is extended from the inside to the outside of the housing 4 as disclosed in FIGS. You can also.

  In some situations, it may be advantageous to include a radiation beam assembly and / or an analysis assembly inside the probe. In one embodiment of the present invention, the radiation beam assembly 10 is a laser beam generating assembly known to those skilled in the art, as disclosed by Kim U.S. Pat. No. 4,986,658. It is.

As best shown in FIG. 3, in one embodiment of the present invention, the laser beam generating beam assembly 10 performs a LIBS measurement method (laser induced breakdown spectroscopy) using the aforementioned LIBS induced plasma. A pulsed laser beam 15 with sufficient power to be performed on the liquid 20 (for example, molten aluminum) through the formation of 17 together with an optical fiber cable and / or another optical cable assembly 11. introduce.
A radiation beam assembly 10 known to those skilled in the art is contained in its own housing 21 to transmit a pulsed laser 15 and to a gas-liquid interface, generally indicated at 34. . The laser beam 15 energizes a portion of the liquid at the interface 34 to vaporize the liquid to produce a plasma plume 17 having elements representative of the elemental composition of the liquid.
Typically, as soon as the laser pulse lasting about 1000 nanoseconds ends, an inversion in the spectrum of the plasma plume 17 is caused by absorption of radiation emitted from the hot interior of the plasma plume to the relatively cool exterior. The radiation emitted by the outside is then measured in a short time by means of a spectrometer 157, radiometer or other device suitable for the type of emission placed inside or outside the probe assembly.
Other methods for generating a radiation beam in contact with a liquid to generate a detection species for analysis are known to those skilled in the art and are described in detail below.

  In accordance with an embodiment of the present invention, a nozzle assembly capable of forming a stable interface in the form of a stable volume of inert gas between the probe assembly 2 and the temperature controlled liquid is provided on the housing 4. Provided at the front end 8.

The nozzle assembly is best shown in FIG. The nozzle assembly 12 includes a bottom 14 having at least one, preferably a plurality of separately installed channels 16. As best shown in FIG. 4, the channel 16 has a first opening 17 at the bottom 14 and a second spaced opening 19 at the side of the bottom 14. Channel 16 allows inert gas (see FIG. 3) from source 23 to move from housing 4 through conduit 18 to opening 25 to form a stable volume interface with the liquid. to enable. The gas then flows from the channel 16 into the dissolved liquid through the second opening 19 if the opening 19 is below the surface of the liquid. The inert gas is supplied via channel 16 in a manner that provides sufficient back pressure between the probe assembly 2 and the liquid to maintain a stable volume of inert gas.
For example, if the probe is immersed in a molten aluminum tank 100 cm deep, the pressure at the bottom of the tank will be approximately 1.25 times the pressure of seawater. If the front end of the probe must be located at the bottom of the tank, the inert gas must be supplied at a greater pressure (approximately 1.25 times the pressure of seawater).
Providing a concave shape at the bottom 14 makes it easier to maintain the desired pressure, as shown in particular in FIG. 4 where the nozzle assembly 12 proximate the channel 16 is shown. In particular, the probe assembly 2 of this embodiment faces the downstream of the liquid that allows the development of inert gas at the interface.

In operation, inert gas is supplied from the nozzle assembly 12 to the opening 25 via the conduit 18 under pressure. The pressure of the inert gas is sufficient to form a stable volume of inert gas at the liquid interface. Once a stable volume is obtained, the gas continues to enter through the opening 25. At the same time, if the liquid is a raw material melted, a part of the gas whose temperature has increased rapidly enters the channel 16 via the first opening 17 and passes through the second opening 19. I go outside.
Since the side opening 19 is relatively high in the liquid relative to the bottom 14 of the probe assembly, the side opening 19 in the side opening 19 compared to the foremost surface or tip of the probe assembly. The liquid pressure is slightly low. This slight pressure difference is sufficient to drain the flowing gas from the side opening 19.
Thus, the open chamber at the tip of the probe is filled with a gas at the pressure of the liquid at the tip, creating a stable gas-liquid interface that reacts sensitively to liquid measurements. When the probe assembly is raised or lowered, the gas flow rate may be changed via the side opening 19 to make the gas pressure at the tip equal to the liquid pressure, To maintain a stable liquid-gas interface. In order to ensure sufficient pressure to maintain the flow of inert gas, a device (not shown) for monitoring the flow known to those skilled in the art may adjust the gas pressure so that the flow of inert gas does not stop. It may be necessary to adjust higher.

  In accordance with a preferred embodiment of the present invention, the inert gas is continuously flowing into the stable volume via the opening 25 and away from the stable volume via the channel 16, in part. Prevents the inert gas from experiencing dramatic temperature changes. This is particularly important when the liquid is at a high temperature such as molten metal or glass. By maintaining a continuous flow of inert gas, the temperature of the inert gas is such that the radiation beam assembly remains at a relatively constant cold temperature so that the radiation beam assembly is free of distortion of the radiation beam and / or the assembly itself. Prevent exposure to excessive heat that causes damage.

  The channel 16 may extend beyond the body of the probe assembly, as shown in FIGS. Gas bubbles 154 present in channel 16 stir the liquid-gas interface to the extent that it would interfere with the desired measurement of the liquid. As shown in FIG. 22, the channel 111 may extend away from the measurement site to minimize the effects of bubbles 154 at the liquid-gas interface. The channel 111 may be horizontal as shown or may face upwards toward the surface of the liquid.

  Another embodiment is shown in FIG. A channel 113 extends to the liquid surface. In this embodiment, all the gas discharges the liquid without bubbling. Great care must be taken in this embodiment because sufficient pressure exists at the liquid gas interface at the front end of the probe assembly 8 to prevent the liquid from flowing out. Because this embodiment does not compensate for depth changes, a valve 115 that limits the flow of air from the channel 113, even if the channel itself is not designed to compress the flow of gas sufficiently to perform the same function. An appropriate pressure level is maintained. It is known to those skilled in the art to design such a channel and / or to use a valve that suitably compresses the flow rate to maintain pressure.

  Two gas streams, at least one consisting of inert gas, or one liquid stream and one inert gas are used instead of a single inert gas stream. As shown in FIG. 17, the piping in the probe assembly flows around the temperature sensitive component of the probe assembly and discharges the liquid 181 inside or outside the probe assembly. I will provide a. It can also provide better protection than the protection against thermal damage provided by a single gas flow. If a liquid such as water is used instead of gas, the gas creates a stable interface while water is used for cooling purposes.

  The inert gas flow stability and intimate maintenance at the same low temperature, which serves as the interface 34 between the probe assembly 2 and the fluid 20 (shown in FIG. 3), is located away from the channel 16. This is the result of providing a continuous flow of gas from the outlet port 25. The inert gas that escapes from the channel 16 to the liquid 20 is continuously replenished by the supply of fresh inert gas from the port 25. As used herein, the term “stable amount” refers to new inert gas inflows and channels entering the opening 25 when, for example, a fixed amount of inert gas at the interface 34 is maintained during any measurement period. Means harmony between avoidance of inert gas from 16. In this way, the nozzle assembly 12 facilitates maintaining a stable amount of inert gas due to the coordinated amount established between the inflow of inert gas from the conduit 18 and the release of inert gas from the channel 16. To.

  Alternatively, as shown in FIG. 9, some of the gas that enters through the conduit 18 exits the port 27 in the housing 4. In particular, excess inert gas flows from the housing 4 through the passage 29 surrounding the probe assembly 2 and enters the outlet port 27 which flows from the conduit 31 to the outlet 33. This configuration may cause damage to the interface stability due to the large amount of gas supplied to cool the probe assembly 10 or cool the liquid to solidify, or at the front end 8. This is useful when the liquid is put in and the measurement is harmed. A valve 35 or other flow control device is installed in the conduit 31 to control the total amount of gas flowing out of the port 27 and conduit 31 to the outlet 33. The conduit 31 does not need to be disposed on the side of the housing 4, but can be disposed at an arbitrary position from the place where this function is performed.

The probe assembly need not be inserted perpendicular to the liquid, as shown in FIG. In order to easily adapt the probe assembly in many different situations, the front end 8 of the probe assembly 10 is configured to be inserted at an angle to the surface of the liquid shown in FIG. For example, according to the present invention, the probe assembly can be inserted from a port located on the side wall of the container. For example, if the probe assembly is inserted into the furnace wall at an angle of 45 degrees, the bottom surface is horizontal or has a removable end with a bottom end that is machined corresponding to the insertion angle θ. To provide the tip 37, it is machined at 45 degrees relative to the longitudinal axis of the body of the probe assembly. By matching the angle of insertion with the angle of the front end 8 of the probe, the liquid surface is parallel to the plane of the front end 8. This embodiment can maintain the liquid surface from the probe assembly. By maintaining a channel 16 for carrying an inert gas to a liquid parallel to the plane of the front end 8, the channel rises with respect to the front end 8. As described above, a stable amount of inert gas is created at the front end 8 depending on the rising position of the channel 16.
In certain applications it is necessary to know the exact location of the liquid gas interface. In this example, it is advantageous to incorporate an interface sensing assembly that accurately determines the surface of the liquid. If the liquid is conductive, one embodiment of the interface sensing assembly uses an electrical circuit consisting of an electrical wire having a bare end positioned adjacent to the bottom end of the probe assembly. When the liquid gas interface occurs at the bare end, the electrical circuit is combined between the two wires, thereby generating a signal for the operator or system to take appropriate action as described below. FIG. 19 shows an example of an embodiment of the invention where the wire 46 is mounted low from the rear end 6 of the probe assembly 2 until the tip reaches the front end 8. The wire 46 is connected to the detection device. And since the minimum required pressure is used to maintain the electrical circuit, the operator can fine tune the gas pressure, such as through the use of automatic control. In this way, the operator can ensure the exact position of the liquid gas interface created by the electrical circuit consisting of the wire 46 and the conductive liquid. Similar methods known to those skilled in the art are used when the operator requires a minimum or maximum distance of the interface from the tip of the probe assembly.

  The interface sensing assembly is useful in disturbing the liquid gas interface where the foaming motion of the gas exiting the side opening 19 causes fluctuations. Whether this occurs depends on factors such as gas pressure and velocity, and liquid properties such as concentration and viscosity. In this case, the operator can have a wide variety of data collection methods depending on the nature of the liquid and / or the environment in which the measurements are made. For example, a substantial limitation on the measurement period. For example, the operator may choose to use circuit completion to trigger a measurement event, or the operator may choose to do as a continuous set of measurements. Thereafter, the operator correlates the time history of the interface with the measurement. It can be known when the interface is in a stable position for measurement, as measured by the mechanism described above.

  While some inert gas enters the liquid and avoids as bubbles, a stable amount of inert gas is allowed by allowing new inert gas to escape from the channel 16 via the side openings 19. Inert gas is maintained through the conduit 18. In this way, by controlling the pressure of the inert gas from the conduit 18, a stable amount of inert gas is maintained at the interface in the context of a continuous flow of fresh inert gas. The stable amount of inert gas is a temperature that is controlled by a fixed inflow of new gas and therefore prevents reaching the extreme temperature that occurs when the liquid is a molten metal. By placing one or more temperature sensors (eg, thermocouples) within the probe assembly, the temperature of the gas is managed. Illustrated and referenced in FIG. 2 which shows that a temperature sensor 42 is provided below through the rear end 6 of the probe assembly. In this embodiment, the temperature sensor is connected to an outer temperature measuring device 43, which is known in the prior art by a conductive wire 44. The output from the temperature sensor is used by a pressure regulator that controls the flow of inert gas to ensure that the gas pressure is increased to maintain the proper temperature within the probe.

  As used herein, the term “inert gas” refers to any substance that produces a detection species from a liquid and does not affect the apparatus and method of the present invention that analyzes at least one property of the liquid obtained from the detection species. Gas is available. Examples of such inert gases typically include nitrogen, argon and helium. Inert gases are not limited to gases generally recognized as inert gases, and can include gases that react quickly in situations other than those contemplated herein. In some applications, reactive gases were used. In such an application, the reaction gas provides some utility to the measurement process and can also serve as a cooling gas for the probe, an aerodynamic window, or both.

  The operation of the embodiment of the invention shown and described in connection with FIGS. 2-4 is shown in FIG. Referring to FIG. 3, a container 30 such as a ceramic furnace containing the analyzed liquid in a fixed form. A probe assembly 2 having a conduit 18 for the flow of inert gas is generally indicated by reference numeral 10 (in FIG. 2) and includes a radiation beam assembly including a silicon carbide tube or the like within the housing 4. 4 is included. The container contains a liquid 20 (eg, molten metal or glass), and the probe assembly 2 is inserted below this surface. The pressure generated by the flowing inert gas provides a stable amount of inert gas 34 at the probe assembly 2 and liquid 20 interface. A stable amount of inert gas pressure is applied from the conduit 18 while allowing excess inert gas to escape from the channel 16 through each opening 17 and 19 (shown in FIG. 4) in the nozzle assembly 12. Preferably, it is maintained by a continuously flowing inert gas. A radiation beam (eg, a laser beam) is transmitted to the probe assembly via fiber optic cable 11 in a known manner and is contained in lens housing 21 from a stable amount of inert gas 34 at the interface of liquid 20. The lens is focused.

  While the present invention is described as sensing a property of a stationary liquid, the present invention is used to sense at least one property of a liquid in a flowable situation as shown in FIG. . The probe assembly 2 shown diagrammatically in FIG. 5 is submerged for taking measurements from inside a stationary or flowing liquid and placing the probe assembly tip on the surface of the flowing liquid Can measure the surface of the liquid 20 in a stationary or fluid state. This has a significant advantage in metal products that can be poured from furnaces into differently shaped molds. In this embodiment, the radiation beam is focused on the upper surface of the liquid to produce a detection species to face the interior of the liquid.

  Liquids analyzed in accordance with the present invention need not limit the performance of the tank or conduit. The present invention uses a liquid that is in a static state or a flowing state in a state where water is naturally in the sea, a lake, a river, or the like, or in a state that is artificially generated, such as a dam lake.

  If the probe assembly 2 is used only for analyzing the quiescent state or flow state of the liquid surface, the probe assembly 2 with the radiation beam assembly is fixedly suspended above the liquid as shown in FIG. Typically hung at a height of a few inches to a few feet. As specifically shown in FIG. 11, this arrangement is particularly suitable for analyzing the flow of the liquid flow state denoted by reference numeral 80. It will be appreciated that the distance between the radiation beam assembly and the liquid will be selected by the detection species and will be determined by a person skilled in the art in a certain procedure.

  The present invention also encompasses the use of multiple probe assemblies to measure multiple locations in a liquid contained in single or multiple containers. As shown in FIG. 6, the probe assembly 2 is shown in two containers 30a and 30b for the purpose of illustrating a typical example. The probe assembly is placed in the water at the same depth at different locations. The probe assembly may be disposed at different depths in the container, or at least one probe assembly may be disposed on the liquid surface. The probe assemblies 2 may be connected to each other by a common conduit 36 to exchange information about the detected species and return the information to a smaller number of sensing devices. For this purpose, a single sensing device such as a common spectrometer 157 is preferably used.

  The apparatus of the present invention may be used so that multiple relatively inexpensive probe assemblies can be used simultaneously with the sensing device and radiation beam assembly described herein as “multiplex transmission”. An embodiment is shown in FIG. 12 in which the radiation beam is directed to a different probe assembly while detection species are collected from each probe assembly. A radiation beam assembly such as laser 50 alternately irradiates each probe assembly (not shown) via rotating mirror 52. The mirror 52 is tuned to the laser so that one pulse enters one of a plurality of lenses 54 corresponding to each of the probe assemblies, through an optical fiber or tube indicated at 56 respectively. The laser pulse is spaced more than necessary for the sensing device (eg, spectrometer 157) to read the LIBS signal 171 so that the mirror rotates to the correct position for the next pulse. Sufficient time is secured. The signals generated corresponding to the detected species are alternately received and read by the spectrometer 157. This allows multiple measurements from different probe assemblies to be made substantially simultaneously. The reading comes from one furnace (similar device containing liquid) 156 and the probe assembly can be inserted into several furnaces.

  The main advantage of this method is that the probe assembly is inexpensive compared to measuring instruments that detect and analyze the species detected. By multiplexing the probe assembly, it is possible to achieve sufficient savings compared to several independent probe assemblies.

  The device of the present invention is capable of detecting the substance and concentration of an element (for example, zinc, nickel, aluminum, etc.) in a liquid. When the device is used with a laser beam generator, the detected species again emits optical radiation. The light is then collected by an optical fiber and transmitted to a sensing device such as a spectrometer 157 in a conventional manner. This characteristic line radiation is resolved spectrum by spectrum 157. The spectrometer 157 accurately identifies elements in the liquid. In addition, the magnitude of the line radiation signal is measured quantitatively, thus determining the concentration of each element present. Every atom emits a number of characteristic spectral lines when it is excited to a plasma state.

  The advantage of the device according to the present invention is that it measures the elemental composition of the liquid immediately and without changing location. This makes it possible to continuously read the liquid properties at any point. This is very valuable for the end user of the system described above. For example, a metal manufacturer can know the composition of an alloy without sending a molten metal sample to the laboratory.

  Another advantageous feature of the present invention is that parts of the device that are expensive and require care (eg, spectrometer 157 and laser 50) are separated from the sensing point. The part can then be placed in a safe environment so as not to be damaged. This is particularly advantageous when measuring the properties of the molten material.

  Although laser beams generated in the assembly have been illustrated, methods of transmitting light or the resulting signal (ie, the detection species) can be applied to the present invention. One example is shown in FIG. In FIG. 7, a cavity or light pipe 60 through which light passes is used, through which a laser beam or light (ie, a detection species) 62 passes through a probe assembly in the cavity, indicated at 64. One or more mirrors 66 can be used in the cavity 64 to redirect the laser or light 62 as desired.

  This method of transmitting light is particularly effective when transmitting high power laser pulses over long distances. Fiber optic cables have limits on the power they can transmit without damaging the fiber optic cable. In a tunnel or pipe through which light passes, curved mirrors and / or combinations of mirrors and lenses prevent light from deviating from the desired path. Another advantage is that light pipes are generally less expensive than fiber optic cables. The light pipe may be used in combination with an optical fiber.

  In addition, in conjunction with the laser assembly described above, the present invention can be used with devices that create a highly concentrated and high energy source. An example of a well-known mechanism for measuring at least one property of a liquid utilizes an electric arc similar to an electrode plug used in automobiles that boil and ionize the minute raw material being analyzed. This process is similar to the LIBS process. However, arcs are used instead of laser radiation to excite the liquid. Commercial instruments for this purpose are sold, for example, by Metrex International (Finland) or Spectro Analytical Instruments (Germany). In the present invention, the arc spark device can be disposed in the vicinity of the inside of the liquid. Moreover, light can directly approach the inside of the liquid. The cooling gas or liquid passing through the probe assembly provides a temperature controlled environment for the arc spark device, as shown in FIG. In this embodiment, the power source is connected to the electrode 135 via the wiring 131 from the power source 133. The electrode 135 is inserted through the front end of the probe housing 8 to slightly interfere with the beam path in the housing 10. A voltage is applied to the electrode that is large enough for the spark to jump between the electrode and the liquid. The optical assembly collects the light generated by the spark and the light emitted by the plasma into the measuring device 13 via an optical fiber. The measuring device 13 determines the elemental composition of the liquid from the detected species.

  An analytical instrument for measuring liquid properties is exemplarily shown. Here, spectrometers such as Acton Research Model 300 (Acton Research Model 300) and Echelle Model ESA 3000 (Echelle Model ESA 3000) manufactured by LLA are shown. However, any device that can measure the detected species from the plasma can be used. One such example is a radiometer (e.g., Optoelectronics Model DET 210 Photodetector) that measures the total radiation dose within the wavelength of light. Such a device is more economical when measuring concentrations from small amounts of elements.

  Instead, especially over long distances, instead of connecting optical fibers similar in arrangement to those shown in FIG. 7, there is an optical tunnel that forms a closed box with mirrors that are appropriately arranged at the corners. May be used.

  Alternatively, one laser beam assembly can be used for each probe assembly and all radiation may be collected by one sensing device (eg, a spectrometer). This configuration is effective when the laser is inexpensive or when other inexpensive radiation sources are used. Similarly, if a radiometer or other inexpensive radiation analysis device is used, it is practical to multiplex a single laser or other radiation source and use one radiation analysis instrument for each probe assembly. May be the target.

  In accordance with the present invention, a laser or other radiation transmitted to the probe assembly 2 and one of the detected species transmitted from the probe assembly 2 emitted from the liquid as shown in FIGS. A fiber cable is shown. This is not a limitation of the present invention as two or more fiber optic cables or other conduits of the transmitted signal can be used simultaneously. In particular, it is effective to use an optical fiber for transmitting light to the probe assembly 2 or a second optical fiber for relaying a detection species (for example, an optical signal) from the probe assembly 2. This is because great care has been taken to avoid damaging the optical fiber when connecting the fiber to a high energy source such as a laser. Furthermore, changing the connection to separate the emitted light from the probe assembly is to complicate the design to the extent impractical due to cost and reliability issues.

  Two or more lasers or a single laser that are rapidly and continuously pulsed are used to increase the signal output to the noise rate. Referring to FIG. 8, the laser is pulsed 163 and focused at a certain distance on the liquid surface, for example, about 1 mm. The second laser focused on the liquid surface 84 is pulsed 164 after approximately two microseconds. The combination of the two pulses greatly increases the signal over that obtained with a single laser. This method is based on Stratis, DN, Eland, KL, Angel, SM, “Dual-Pulse LIBS Using a Pre-ablation Spark for Enhanced Ablation and Emission ”(Applied Spectroscopy, 54, No. 9, 2000, pp. 1270-1274).

  In order to ensure that the laser pulse path is aligned in the same linear order (or nearly so) rather than perpendicular to the other, in use with the present invention, such as Stratis The device can be changed. One embodiment of this configuration is shown in FIG. Other configurations are possible and this FIG. 20 is not intended to limit the embodiment. The two lasers described and currently used by Stratis et al. Have a variety of wavelengths. The shorter wavelength beam 86 of light 86 and the longer wavelength beam 88 of light are focused on the liquid surface 84 by a lens 82. Like the lens housing 21 shown in FIG. 3, this assembly is usually in the housing. Typically, materials used for lenses focus on shorter wavelength light at shorter distances compared to longer wavelengths. This phenomenon is used to change the assembly revealed by Stratis and others to the same linear order. To begin the measurement process, a pulse of laser light of the shorter wavelength is first transmitted and focused at a point 87, which is approximately 1 mm above the liquid surface. At a point, sparks are generated in the gas on the surface. The longer wavelength second laser pulse is transmitted after a few microseconds, and if the lens is properly selected in a manner known to those skilled in the art, the longer wavelength light is reflected on the surface of the liquid 89. Focused. Then create a LIBS spark on the surface.

  Furthermore, the present invention extends devices such as Stratis to the analysis of liquids and the measurement of both the interior and surface of a liquid rather than just its surface. Either or both lasers can be replaced, for example, by an electric spark generator as described above.

One way to increase the accuracy of LIBS measurements is to utilize sensors to measure acoustic signals from LIBS sparks. Referring to FIG. 21, a sonic sensor 100 (eg, a microphone) collects acoustic radiation resulting from a LIBS spark. This signal is transmitted by wire 102 to a sound wave measuring device, shown generally as 104. It has been found that incorporating the magnitude of this acoustic signal into the analysis of LIBS radiation increases the accuracy of liquid concentration measurements.
This method is described by Chaleard C, Mauchen P, Uebbing Andre J, Lacour LL, and Geesten C. It is shown here for reference that it is described in “Correction of Matrix Effects in Quantitative Elemental Analysis with Laser Ablation Optical Emission Spectrometry” (Journal of Analytical Atomic Spectrometry, February 12, 1997, PP 183-188). Keep it.

There are other methods for making qualitative and quantitative measurements in liquids that do not rely on plasma and are included in the present invention. One example is known as X-ray fluorescence (XRF) shown in FIGS.
In this method, x-rays are generated by a suitable x-ray beam generation assembly and directed to the liquid to be analyzed. The liquid absorbs X-rays and emits radiation with the wavelength characteristics of the elemental composition of the liquid. Commercial units from, for example, the Niton Corporation of Billerica in Massachusetts or Metorex International in Finland can be used for use in embodiments of the present invention.
Evaluation of existing offerings was recently announced in Rony E. Ayala Jimenez's “Total Reflection Spectrochmica Acta” (Part B 56 2001 pp.2331-2336). Currently, these units combine X-ray generation and detection hardware into one small unit. As shown in FIG. 24, by placing the x-ray assembly inside the probe housing, the sensing assembly can be brought about inside the liquid. Referring to FIG. 24, the electrical wire 123 provides power from the power supply 127 to the fluorescent X-ray assembly 125.
Alternatively, power can be provided by one or more batteries installed within the probe assembly 8. The fluorescent X-ray assembly 125 includes a prominent X-ray generator that directs the X-rays to the front end of the probe assembly 8. X-rays emitted from the liquid are collected in an assembly of fluorescent X-rays, and the resulting measurement is transmitted to the measurement device 121 through an electrical wire 123. This electrical signal also contains information about the properties of the liquid including its elemental composition.

  For example, if it is not feasible to install the x-ray assembly device inside the probe assembly due to space constraints, the device will indicate the probe housing and the length of the housing as shown in FIG. Installed outside the line. The X-ray fluorescent assembly 125 can be placed on a tube 127 through which X-ray radiation is directed towards the liquid. Niton Corporation, for example, provides fluorescent X-ray units with telescopic protrusions that combine the ability to direct X-rays in a desired direction.

As shown in FIG. 13, if the detection species obtained from the liquid is essentially non-electromagnetic, then, for example, as a sound wave, then inside the probe assembly or outside the adjacent probe assembly. Through a transducer 70 (eg, an ultrasonic transducer), the detected species can be converted into an electrical signal. The signal is then removed from the probe assembly through electrical wire 74 for analysis. If the detected species is electromagnetic (ie, light), this configuration can also be performed and the transducer 70 converts the electromagnetic signal to an electrical signal.
Optionally, these electromagnetic signals can be transmitted through wireless signals or other wireless communication methods. This is advantageous when the probe assembly is capable of self-output through a battery or another on-board energy source.

The ultrasound probe assembly can be utilized, for example, to measure liquid density and flow rate. Ultrasonic density measurement probes are commercially available from, for example, Thermo Measure Tech, Austin, Texas. For example, a device such as that shown in FIG. 27 uses two probe assemblies that are spaced apart. One probe assembly emits ultrasound rays and the other probe assembly is receiving the ultrasound rays. The time required for the ultrasound to travel between the probe assemblies is correlated with the density of the liquid.
This method requires a liquid that does not prevent it from being used with the probe material. If the liquid is very hot or prevents it from being used together, such as, for example, a melted material, then the device cannot be used. The combined ultrasonic transducer makes it possible to use the method in these types of liquids.
As disclosed in FIG. 27, two probe assemblies containing ultrasonic transducers are inserted into the liquid. One transducer 145 emits an ultrasonic pulse that is received by the other transducer 147. The signal is transmitted back and forth through the wire 143 to the measuring device 141. Knowing the distance between the sensing assembly and other liquid properties such as temperature and composition allows the fluid density to be calculated by those skilled in the art.

Similarly, to determine the liquid flow rate, an ultrasonic flow meter utilizes the time required for ultrasonic storage to travel between the two probe assemblies. Devices based on this principle are commercially available from, for example, Panametrics Inc. of Houston, Texas.
For the density meter case, it is used to combine an ultrasonic transducer with the present invention for a liquid that does not prevent it from being used in very hot liquids or with common transducer materials as well. Making the method possible.

  Ultrasound and X-ray fluorescence methods are not examples of plasma generation, but are examples of methods for measuring liquid properties that can be incorporated into the present invention. Since these methods release radiation from the liquid and receive the detection species therefrom, they can be used alternatively in the preferred embodiment of the present invention. A protective wall (eg, window 9) can be used to generate a detection species as shown in FIG. 18 instead of a stable amount of gas, electromagnetic or acoustic radiation.

  One application of the present invention is selective in-line alloying that occurs while pouring molten material. In this application, the probe assembly is placed directly on top of the melted material that entered the container as it is being poured from the furnace 156 as shown in FIGS. Data can be used as feedback to control feedstock as well as measure all of its target elements. Alternatively, one or two selected elements such as magnesium or manganese can be measured. While flowing molten material 80 is poured, these elements can be alloyed in the furnace and controlled by input with a sensor (not shown). Alloying balance has already been achieved in conventional furnaces. If only one element is alloyed, then at least one, typically two, radiometers can be used instead of the spectrometer.

 It may be advantageous to use two or more probe assemblies to perform inline alloying as shown in FIG. The two probe assemblies 90a and 90b can share a single laser and spectrometer 94 using the multiplexing technique described above. In this embodiment, one probe assembly 90a analyzes the flow being poured and the other probe assembly 90b is placed in a furnace to analyze a stationary liquid. The advantage of this embodiment is that a two-stage alloying can be performed. The first stage is performed in the furnace and the second stage is performed on the liquid to be poured. This is effective if one alloying element is added in large quantities as indicated by reference numeral 96 and a small amount of one alloying element as indicated by reference numeral 98 is added. In addition, the alloying elements added in large quantities are mixed in a stationary liquid in the metal. There it is easily mixed. In addition, the in-furnace probe assembly 90b can be used to trigger a warning in an incompatible blended melt event. It can be used for the control 175 of a device that can stop the flow of a valve 92 or other material such as a plug in a continuous furnace. They stop the melted metal stream 177 in the event of an incorrect formulation.

 Another application of the present invention relates to converting a conventional batch furnace as shown in FIG. 15 into a continuous furnace. This explanation is sufficient and new working paradigms for the aluminum industry and other similar industries can arise. In this application, the probe assembly 100 is again placed immediately above the molten metal 102 in the furnace 104 as the molten metal is being poured. However, all target elements are read and controlled. The furnace is operated continuously and simultaneously poured from the metal 106 source. It is alloyed without interruption in the furnace. The probe assembly 100 sends the detection species to a sensing device (eg, spectrometer 108) for analysis so that the concentration of one or more elements is recorded. In this way, the operator can adjust the scrap metal supply and the alloying element supply 105 either manually or automatically to be alloyed within conditions. One or more probe assemblies are similarly installed in the furnace (see FIG. 14) to facilitate the process. The benefits of a continuously operating furnace are significant and include energy savings, increased production and reduced emissions.

  A further application of the present invention is its use as a diagnostic tool to measure heat and mass transfer in the melt to improve furnace modeling (i.e. prediction of furnace capacity). Raw materials or alloy materials such as scrap metal are usually added into the melted material. The probe assembly can be immersed in one of the melted materials and the change in melt composition resulting from the addition of new material can be measured as a function of time. A spatial and temporal map of how the composition of the melt changes as new material is added, and this process as shown in FIG. 16 at different locations on the probe assembly 110 is repeated. Is possible. By combining temperature measurements within the capabilities of the probe assembly, for example (FIG. 2, refs. 42-44), temperature variations resulting from furnace loading can be mapped as well.

  Instead, the effect of stabilizing the melted material for a long time can be measured. The melted metal used in production typically consists of many species, some other heavier species, so if the melted material remains unaffected, the element of thought is more natural It creates a melt that settles to the bottom and is layered against the desired homogeneous elements. To date, it is impossible to measure the degree of stratification as a function of downtime or furnace installation. It is possible to learn the stratification process by inserting the probe assembly into different locations at different depths in the furnace and measuring the composition as a function of downtime. The resulting knowledge can then be used to modify operating procedures and furnace designs to avoid stratification.

  Stratification can also occur due to heat flow. When the liquid conducts heat slowly, for example, the molten glass is heated, and that heat is carried unevenly by the flow of heat. These streams can also carry molten elements. The result is a concentration of elements or a drastic drop from a specific location in the tank.

  Information gathered from these experiments will be used to redesign furnaces and work procedures to increase efficiency and produce homogeneous melts. Finally, the computer software used to simulate furnace operations and mixing tanks can combine the temporal and spatial maps described above to increase accuracy. Currently this type of software relies not only on theoretical calculations but on much less capability data than the one collected in the present invention.

1 is a laser-induced breakdown spectroscopy system that is a known schematic for in-situ analysis of dissolved material. 2 is a cross-sectional view of a probe assembly according to an embodiment of the present invention. 2 is a cross-sectional view of a probe assembly according to an embodiment of the present invention submerged in a container containing liquid. FIG. FIG. 4 is a bottom view taken from a cross-sectional view of the front end of the probe assembly according to the embodiment of the present invention shown in FIG. 3. FIG. 2 is a diagram of an embodiment of the apparatus of the present invention used to take measurements of a flowing sample from the surface of a liquid. FIG. 6 is a cross-sectional view of another embodiment of an apparatus of the present invention employing multiple probe assemblies for analyzing liquids contained in multiple containers. FIG. 3 is a schematic diagram of a pipe that can be used to transfer a detected species, such as light energy, from a molten material to a device for light energy analysis to determine the composition of the melted material. FIG. 2 is a schematic diagram illustrating a probe assembly having two lasers for enhancing the signal against the noise ratio of the LIBS method. Another embodiment of the device of the present invention which employs a valve for releasing pressurized gas into the air when there is extra gas at the front end of the device for the purpose of maintaining a stable volume of gas. It is sectional drawing of embodiment. FIG. 6 is a cross-sectional view of another embodiment of the apparatus of the present invention that employs an angled front end to facilitate insertion of the probe assembly relative to the longitudinal axis of the container. FIG. 6 is a schematic diagram of another embodiment of the apparatus of the present invention employed when the apparatus is used to analyze flowing liquid from above the flowing liquid surface. FIG. 6 is a schematic diagram of another embodiment of an apparatus of the present invention employing a plurality of probe assemblies, a single radiation source, and a single instrument for measuring a detection species emanating from a liquid. FIG. 3 is a schematic view of another embodiment of the apparatus of the present invention employing an ultrasonic transducer for performing qualitative and / or quantitative measurements in liquid. 1 is a schematic diagram of an embodiment of the present invention that can be used in the production of metal alloys by in-line alloy manufacturing. 1 is a schematic view of an embodiment of the present invention that can be used in the production of a metal alloy by a continuous power furnace. FIG. 6 is a schematic diagram of an embodiment of the present invention that can be used to simultaneously measure liquid properties at multiple locations within a container. At the front end of the device, a gas or liquid stream that is separated from the gas used to maintain a stable volume is used to maintain the temperature in the device at an operable temperature. FIG. 6 is a cross-sectional view of another embodiment of the apparatus of the present invention. FIG. 3 is a cross-sectional view of another embodiment of the apparatus of the present invention in which a window is employed in place of a stable volume of inert gas at the front end of the apparatus. FIG. 6 is a cross-sectional view of another embodiment of the device of the present invention providing an assembly for detecting the liquid level at the front end of the device. FIG. 6 is a schematic diagram of a further embodiment of the apparatus of the present invention using two different wavelength lasers on the same line to measure the properties of the liquid. FIG. 6 is a cross-sectional view of a further embodiment of the apparatus of the present invention employing a sonic sensor for detecting a detection species of a sonic energy state emitted from a liquid. FIG. 6 is a cross-sectional view of a further embodiment of the apparatus of the present invention employing an extended passage for delivering a flowing inert gas into the liquid. FIG. 6 is a cross-sectional view of a further embodiment of the apparatus of the present invention employing an extended passage for delivering a flowing inert gas from the front tip of the probe assembly to the surface of the liquid. FIG. 6 is a cross-sectional view of a further embodiment of the apparatus of the present invention employing an X-ray fluorescence assembly for determining the composition of a liquid. FIG. 26 is a cross-sectional view of a further embodiment of the apparatus of the present invention similar to FIG. FIG. 6 is a cross-sectional view of a further embodiment of the apparatus of the present invention employing an arc electrode for generating a plasma at the gas-liquid interface at the front end of the probe assembly. FIG. 6 is a schematic diagram of a further embodiment of the apparatus of the present invention employing two probe assemblies including an ultrasonic transducer.

Explanation of symbols

2 .... Probe assembly 4 ... Housing 6 ... Rear end 8 ... Front end 9 ... Window 10 ... Radiation Beam assembly 11 ... Fiber optic cable 12 ... Nozzle assembly 14 ... Bottom 15 ... Pulse laser beam 16 ... Channel 17 ... ... first opening 18 ... conduit 19 ... second remote opening 20 ... liquid 21 ... housing 25 ... opening 111 .... Channel 156 ... Furnace

Claims (51)

a) a housing having a front end;
b) Inert gas generating means comprising an inert gas source, a conduit for leading the inert gas to the front end of the housing, and a lower flow from the inert gas source, providing a stable volume of inert gas to the front end of the housing and liquid And at least one probe assembly at the front end of the housing comprising means for moving the interface and the probe assembly to any depth or angle in the liquid;
c) means for generating a radiation beam sufficient to vaporize a portion of the liquid to the detection species and for sending the radiation beam through the front end of the housing to the interface between the liquid and a stable volume of inert gas. A radiation beam assembly comprising means;
d) detection means for receiving the detection species and detecting at least one characteristic of the liquid from the detection species;
An apparatus for measuring at least one characteristic of a subsurface liquid comprising: The apparatus of claim 1 wherein the inert gas generating means further comprises means for producing a continuous flow of inert gas to the front end of the housing. The apparatus of claim 1 wherein the means for generating the radiation beam is located external to the housing. The apparatus of claim 1 wherein the means for generating the radiation beam is disposed within the housing. The apparatus of claim 1 comprising a plurality of probe assemblies. The apparatus of claim 1, wherein at least one probe assembly is disposed in the liquid. The apparatus of claim 1, wherein the at least one probe assembly is disposed at or beyond a surface of the liquid. The apparatus of claim 1 wherein the liquid is a molten raw material. The apparatus of claim 1 wherein the liquid is a molten metal or molten glass. The apparatus of claim 1 wherein the radiation beam assembly comprises means for forming a radiation beam comprising at least one wavelength from the electromagnetic spectrum. 11. The apparatus of claim 10, wherein at least one wavelength is selected from the group consisting of x-ray, ultraviolet, wireless, infrared and microwave. The apparatus of claim 1 wherein the radiation beam is a laser beam. The apparatus of claim 1 wherein the radiation beam is a sound beam. The apparatus of claim 1 wherein the detecting means is a spectrometer. The apparatus of claim 1 wherein the detecting means is a radiometer.   The apparatus of claim 12 comprising a laser induced breakdown spectroscopy system.   The front end of the housing comprises a nozzle assembly that stabilizes the inert gas in contact with the liquid and at least one first opening that allows the inert gas to contact the liquid. 2. The apparatus of claim 1 comprising pressure control means for maintaining capacity.   18. The apparatus of claim 17, wherein the pressure control means comprises at least one channel that moves the inert gas away from the housing-liquid interface.   A first opening for receiving an inert gas; and a first opening located above the at least one first opening when the device is operatively positioned to determine the characteristic. The apparatus of claim 18, comprising two openings.   The apparatus of claim 17, further comprising temperature control means for controlling the temperature within the apparatus.   21. The apparatus of claim 20, wherein the temperature control means further comprises a second flow of gas or liquid that is not in contact with a stable volume of inert gas but is in close proximity.   20. The apparatus of claim 19, wherein the second opening is located below the surface of the liquid.   20. The apparatus of claim 19, wherein the second opening is located above the surface of the liquid.   The apparatus of claim 1 further comprising surplus gas discharge means for removing excess gas from the gas used to form a stable volume of inert gas.   2. The apparatus of claim 1 wherein the means for producing the inert gas further comprises a plurality of conduits for delivering a plurality of inert gas streams to the interface.   Liquid is contained in the container, and the container is configured to form an angle θ relative to the longitudinal axis of the container to allow the probe assembly to be inserted into the side wall of the container. The apparatus of claim 1 having a front end of the housing.   27. The apparatus of claim 26, wherein the angle [theta] is about 45 degrees.   The apparatus of claim 1, further comprising an interface detection assembly for detecting the surface of the liquid at a stable volume interface of liquid and inert gas.   29. The apparatus of claim 28, wherein the interface detection assembly further comprises electrical circuit means at a front end of the housing, and forms an electrical circuit when the electrical circuit means contacts a liquid surface.   30. The apparatus of claim 29, wherein the liquid is an electrically conductive liquid.   The apparatus of claim 1 wherein the liquid is flowing.   32. The apparatus of claim 31, wherein the at least one probe assembly is disposed above the surface of the fluid in liquid state.   The apparatus of claim 1 for measuring at least one property of a liquid at the surface of the liquid, wherein the at least one probe assembly is fixedly suspended above the liquid.   The apparatus of claim 1 comprising a plurality of probe assemblies.   34. The apparatus of claim 33, wherein the plurality of probe assemblies are located at different locations within the container containing the liquid.   35. The apparatus of claim 34, wherein the plurality of probe assemblies are disposed at different depths within the container.   34. The apparatus of claim 33, wherein the plurality of probe assemblies are operatively connected to a few radiation beam assemblies.   The apparatus of claim 36, wherein the plurality of probe assemblies are connected to a single radiation beam assembly.   34. The apparatus of claim 33, wherein the plurality of probe assemblies are connected to a smaller number of sensing means.   40. The apparatus of claim 39, wherein a plurality of probe assemblies are connected to a single sensing means.   13. The apparatus of claim 12, comprising an optical cavity for transmitting the laser beam to the liquid for the sensing means and to the detection species from the liquid.   The apparatus of claim 1 wherein the radiation beam assembly is an arc discharger.   Consisting of an electrode spaced apart from the liquid and electrically connected to the arc discharger, said arc discharger being sufficient to move the arc from the electrode to the liquid in order to generate a detection species from the liquid 43. The apparatus of claim 42, wherein the apparatus generates electrical energy.   The apparatus of claim 1, wherein the radiation beam assembly comprises a method for delivering a plurality of radiation pulses to a stable interface in a method for enhancing a signal to a noise ratio.   44. The apparatus of claim 43, wherein the radiation beam pulse is collinear. The apparatus of claim 16, further comprising a sensor for measuring a sound wave signal generated from the laser guided breakdown spectroscopy system. An apparatus according to claim 1, characterized by a radiation beam assembly comprising an ultrasonic beam assembly characterized in that the properties of the liquid to be measured include density and flow rate. a. A housing having a front end;
b. A probe assembly provided at a front end of at least one housing, the probe assembly comprising means for moving the probe assembly to any depth or angle of the liquid;
c. A radiation beam comprising means for generating sufficient beam radiation to volatilize a portion of the liquid into the detection species and means for transmitting the radiation beam through the front end of the housing to the interface between the liquid and a stable amount of inert gas. Assembly,
d. Sensing means for receiving a detection species and sensing a property of at least one liquid from the detection species;
An apparatus for measuring at least one property of or below a surface of a liquid comprising: 49. The apparatus of claim 48, further comprising a protective wall between the radiation beam assembly and the liquid, the protective wall being capable of passing the radiation beam to generate a detection species. At least one probe assembly is directed to a first portion of liquid contained in the container and at least one other probe assembly is directed to a next portion of flowing liquid The apparatus of claim 5. 1. a. A housing having a front end;
b. A probe assembly at the front end of at least one housing, comprising an inert gas source and a conduit for directing the inert gas to the front end of the housing, under the flow from the inert gas source; Said probe assembly comprising an inert gas means for providing a stable amount of inert gas at the interface and moving the probe assembly to any liquid depth or angle;
c. A radiation beam comprising means for generating sufficient beam radiation to volatilize a portion of the liquid into the detection species and means for transmitting the radiation beam through the front end of the housing to the interface between the liquid and a stable amount of inert gas. Assembly,
d. Sensing means for receiving a detection species and sensing a property of at least one liquid from the detection species;
Installing at least one device comprising:
Measuring the properties of at least one liquid from two detected species;
Measuring a property of at least one liquid at or below the surface of the liquid.

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