WO2015113985A1

WO2015113985A1 - Sample receptacle for a measuring device for measuring a dust sample

Info

Publication number: WO2015113985A1
Application number: PCT/EP2015/051655
Authority: WO
Inventors: Erhard Magori; Gerit Ebelsberger; Alexander Michael Gigler; Remigiusz Pastusiak; Hans Weber; Wolfgang Zöls
Original assignee: Siemens Aktiengesellschaft
Priority date: 2014-01-31
Filing date: 2015-01-28
Publication date: 2015-08-06
Also published as: DE102014201763A1

Abstract

The invention relates to a sample receptacle (1) for a measuring device for the quantitative optical measurement of a dust sample, comprising a measurement pocket (3) which is surrounded by a housing (2) for receiving the dust sample and comprising a separating element (4) which is received in the housing (2) and the first face (5) of which faces the measurement pocket (3) and the opposing second face (6) of which faces the measuring device. The sample receptacle (1) comprises at least one supply device (7) for conducting a fluid by means of which the sample receptacle (1) can be cleaned of dust and/or the temperature of the sample receptacle can be controlled in order to allow a more precise determination of the properties of a dust sample.

Description

description

Sample holder for a measuring device for measuring a dust sample

The invention relates to a sample holder for a measuring device for non-contact measurement of a dust sample according to the preamble of claim 1. It further relates to a method for operating such a sample holder.

In many industrial areas, dusty substances are transported via pipelines. Such dusty substances may include, for example, dust coal, cement, flour or other powdery substances. In order to monitor the properties of these dust-like substances, a measuring pocket can be provided, in which a sample of the dust accumulates, which can then be measured optically by means of a suitable measuring head, possibly with a spectroscopic measurement. This can, for example, a

Moisture or the homogeneity of a mixture can be monitored. If the measuring head is not allowed to come into direct contact with the dust to be measured, a suitable separating element can be used for the respective measuring method in order to protect the measuring head from the dust. By way of example, the separating element may comprise a window for an optical measurement, an insulator for a dielectric measurement, a nonmagnetic material for a determination of the permeability number, or a correspondingly suitable membrane for an acoustic impedance determination.

It is the object of the present invention to provide an improved pocket-shaped sample receptacle which makes it possible to more accurately determine the properties of a dust sample.

This object is achieved by a device and a method according to the two independent claims solved. Advantageous embodiments will become apparent from the dependent claims, the description and the figures.

A sample holder according to the invention for a measuring device for non-contact measuring, in particular for spectroscopic measuring, a dust sample, has a measuring pocket surrounded by a housing for receiving the dust sample, and a separator inserted into the housing, the first side of the measuring pocket and the opposite second side of the measuring device is facing. This separating element can represent a connection surface for a measuring head. In its concrete embodiment, in particular in its material, it is adapted to the intended measuring method, ie in particular to an optical measurement, such as a process spectrometer, an impedance measurement, a measurement of magnetic properties such as permeability μ or dielectric constant, acoustic and ultrasonic scanning, a measurement with microwaves or similar known measuring methods. To enable accurate determination of properties of a dust sample, the sample receiver comprises at least one

Supply device for guiding a fluid, by means of which the sample holder of dust can be cleaned and / or specifically controlled temperature. The fluid may in particular be a gas, ie gas mixtures such as, in particular, compressed air or even pure gases such as C0 ₂ or N ₂ . It may be advantageous to use the same fluid in a tempering, which serves to clean the samples, as thus eliminates an additional media supply. It can also be provided in the supply device to each use a different fluid for temperature control of the sample holder and the sensor and for cleaning the sample holder. The use of fans and / or modern coolers and / or pumps for the temperature control of the measuring device is possible, but is considered as a low-maintenance (and not maintenance-free) solution, which is undesirable in many industrial processes. The temperature control of the sample holder has the advantage that heat-sensitive optical probes or generally temperature-sensitive probes unrestricted can be connected to the sample holder without falsifying or preventing measurement results due to a high or low temperature present in the measuring pocket. In particular, a temperature sensor can also be provided here, which makes it possible to regulate a tempering fluid flow in the supply device. Thus, cooling and / or heating can thus be carried out selectively depending on demand. This temperature sensor can then also be combined with a heating element, for example a Peltier element, so that a constant temperature can be set for the measuring device. As a result, probes which can only be operated in a narrow temperature band can also be used. The cleaning of the sample intake of dust has the advantage that a current measurement is not distorted by old dust, possibly originating from a previous measurement. The properties of a dust sample can therefore be determined more accurately, because on the one hand more, that is, temperature-sensitive sensor types can be used and on the other hand, an influence of old sample residues on current measurement results is prevented. So it is a resting measurement of always current, not contaminated by old sample residues, dust samples possible.

In an advantageous embodiment it is provided that the supply device has at least one outlet opening, which fluidically couples the supply device with the measuring pocket and in the direction of the first side of the

Separating element facing, so that the first side of the separating element from the outlet opening with a fluid flow

can be acted upon. This has the advantage that dust on the first side of the separating element, which is not to be measured, is blown away with the fluid and thus can not influence a measurement.

Here it is provided in particular that the outlet opening has the shape of a fan slot. Under a fan Slit here is a slit-shaped nozzle to understand, which has the consequence. This has the advantage that the separating element is subjected to the surface of the fluid flow and a uniform cleaning of the separating element is achieved. In addition, a laminar flow is achieved on the first side of the separating element, in which no swirls occur. Thus, a scratching or wear of the separating element is avoided by dust particles. In a further embodiment of the invention it is provided that the housing has at least two concentric annular elements and the supply device and / or the outlet opening are at least partially formed by surfaces and / or recesses in the surfaces of adjacent elements, in particular one of the annular elements encloses the separator. The sample holder thus has several elements, which are plugged into one another, for example. This has the advantage that the supply device can be relatively easily formed by, for example, the individual, not yet assembled elements are milled or cast in a certain way, so that in a simple manner when joining the elements in particular non-linear sections of the Supply facilities result. Thus, the supply device can be designed to be flow-optimized largely independently of production-related restrictions and, moreover, in case of doubt, for example in the case of a blockage, it is easy to clean by taking the elements apart again and cleaning them one by one. The supply device is thus easily accessible.

It can be provided that the outlet opening and / or the supply device has at least two non-parallel surfaces of two adjacent annular elements. In particular, an outlet opening can be shaped here in such a way that the surfaces which do not run parallel run apart in the outflow direction of the outlet opening. This has the advantage of being so simple an expanding fluid jet can be formed, which in the case of the outlet via the outlet opening advantageously cleans the separating element in the manner described above in a uniform and planar manner. It is thus also possible within the supply device to create an area in which the fluid can optionally expand and thus specifically cools and contributes to improved cooling in the corresponding area. In a further embodiment it is provided that a plurality of outlet openings is present and these are arranged in a circle around the separating element. In particular, six or in particular more than six outlet openings are advantageous here. The exact number depends on the process and depends on the properties of the dust to be blown off. This has the advantage that a particularly uniform free blowing of the separating element can be achieved. This uniform free blowing can also be assisted by the fact that in the supply device at more than one place a fluid feed takes place, in particular on two or more opposite sides of the supply device. Thus, a particularly uniform pressure of the fluid is ensured at the different outlet openings. It can also be provided that the supply device extends at least partially around the separating element. This has the advantage that a plurality of outlet openings can be supplied by the supply device and at the same time the cooling effect is enhanced.

Finally, it may be provided in one embodiment that a part of the supply device extends annularly around the separating element and in particular the annular part of the supply device is closer to the second side of the separating element than the first side. This part of the supply device then forms a temperature control channel. This has the advantage that the area of the sample receptacle is specifically tempered around the separating element. This temperature control then takes place particularly evenly and in particular on the side of the separating element, or the housing around the separating element, which faces away from the measuring pocket and facing the measuring device, so that the measuring device optionally less heated or cooled than without supply device. The tempering can thus be a targeted heating and also a targeted cooling. The invention also includes a method for operating a sample holder for a measuring device for non-contact measurement of a dust sample. In the method, a dust sample is received in a measuring pocket surrounded by a housing and then analyzed by a measuring device inserted into the housing, the first side of the measuring pocket and its opposite second side facing the measuring device. The method is characterized in that the sample receptacle is specifically tempered by means of a fluid guided through at least one supply device and / or cleaned, in particular before or after the analysis of dust. This also results in the advantages mentioned above. In an advantageous variant of the method, the first side of the separating element is provided with an, in particular laminar, flow of the fluid through an outlet opening, which fluidically couples the supply device to the measuring pocket. The flow may also be a turbulent flow. A laminar flow here has the advantage that the applied first side of the separating element is subject to a particularly low scratching. Again, reference is made to the above benefits.

Further features of the invention will become apparent from the following description of preferred embodiments of the invention and from the figures. Showing: 1 is a schematic sectional view of an exemplary embodiment of a sample holder; 2 shows an enlarged detail of FIG. 1, in which an outlet opening can be seen; and

3 shows an enlarged detail of FIG 1, in which a

Temperierungskanal can be seen.

In the FIG identical or functionally identical elements are provided with the same reference numerals.

1 shows a schematic sectional view of an exemplary sample holder. The sample holder 1 is arranged on a flange 13, which belongs to a pipeline which carries dust. In the example shown, the sample receptacle 1 is formed here essentially by a plurality of annular elements 9, 10, 11, 12, a separating element 4 designed as an optic, as well as two opposite gas connections 14. The gas connections 14 could also be connections for another fluid. The different annular elements 9, 10, 11, 12 are arranged in the example concentrically about an axis A and inserted into one another and form a housing 2. The supply device 7 is here, as well as an outlet opening 8, by surfaces and recesses in abutting, adjacent annular elements 9, 10, 11, 12 are formed. Between the different annular elements 9, 10, 11, 12 here are some seals 15 arranged to seal the supply device 7 against a measuring pocket 3 and an outer space.

The separation element 4 designed as an optic, which has the shape of a round disc in the example shown, has a first side 5, which faces the measuring pocket 3, and a second side 6, which faces a measuring device. In the present example, the separator 4 is in a first annular element 9 of the housing 2 is inserted, so that the two sides 5, 6 pass flush into the annular element. As a result, unnecessary fouling is prevented in this case, it can also be selected another specific embodiment.

Adjacent to the first annular element 9, for example, a second annular element 10 is arranged here, which also adjoins the third annular element 11, the fourth annular element 12 and the measuring pocket 3. In the example shown, the third annular element 11 adjoins the first annular element 9, the second annular element 10, the fourth annular element 12 and the flange 13 and receives the gas connection 14. It has a bore, which belongs to the supply device 7, and forms with the first annular element 9 and the second annular element 10 via recesses in the surface of an annular part of the supply device 7, which is a Temperierungskanal 16 via the gas connection 14 in the Supply device 7 to be conductive gas forms.

The fourth annular element 12 adjoins the measuring pocket 3, the flange 13 and the second annular element 10 and the third annular element 11. In this case, the shape of the measuring pocket 3 can also be influenced via the shape of the third annular element 12. In the present case, the shape is funnel-like. Via recesses and a projection, the fourth annular element 12, together with the second annular element 10, forms the outlet opening 8, which couples the supply device 7 fluidically to the measuring pocket 3.

During operation of the sample holder 1, a compressed air is now introduced into the supply device 7 via the two opposite gas connections 14 in the present case, for example at a pressure of 6 to 8 bar. This compressed air is now blown through the outlet opening 8 into the measuring pocket 3 and it becomes while dust such as coal dust or similar particles, which has accumulated on the first side 5 of the designed as an optical separator 4, blow away. The special shape of the outlet opening 8 here allows a large-area, laminar coating of the first side 5 with the air flow, so that scratches in the optics are avoided by swirling dust particles or particles. Since the measuring pocket 3 can have a high temperature of more than 100 degrees Celsius due to process technology, in the example shown the compressed air is also blown through the tempering channel 16. Thus, in the example shown, the first annular element 9 and thus the designed as optics separating element 4, which is indeed held by the annular member 9, cooled. It could, however, also be kept at a certain temperature, ie tempered. This can be on the second page 6 of the

Separating element 4 and a more sensitive sensors than usual be arranged. The tempering channel 16 is here part of the supply device 7 and connected as an annular channel via one or more holes with the gas port 14. In FIG. 1, this connection can not be recognized since it does not lie in the section plane shown.

Since the sample holder 1 is thus cooled and the first side 5 of the separating element 4 designed as an optic can be freed of dust before each measurement, an accurate and in particular spectrometric measurement of the properties of dust in the measuring pocket 3 is possible.

2 shows a detail of FIG 1, in which an outlet opening 8 is shown. The measuring pocket 3, to which the first annular element 9, the second annular element 10 and the fourth annular element 12 as well as the separating element 4 connected to the first annular element 9 abut, are clearly visible here. Here, the outlet opening 8 again fluidically couples the supply device 7 with the measuring pocket 3 and is formed by the two adjoining second and fourth annular elements 10, 12, inter alia by their surfaces 17, 18. The Outlet opening 8 has the shape of a fan slot, since here the surface 17 of the second annular element 10 and the further surface 18 of the fourth annular element 12 are oriented so that they do not run parallel, in such a way that they in the direction of a gas or Compressed air stream, which flows from the supply device 7 through the outlet opening 8 in the measuring pocket 3, diverge. In principle, this fan slot can be formed proportionally in any division by the two adjacent ring-shaped elements 10, 12; For example, three sides of such a fan slot may be formed by one of the two annular elements 10, 12 and another side by the other annular element 12, 10. Via the fan slot, the first side 5 of the separating element 4 can be exposed to a gas flow in a planar manner, so that a uniform cleaning takes place. In principle, any number of such outlet openings 8 can be provided here, for example, a single large annular fan slot along the entire circumference of the separating element 4 is also possible.

3 shows a further detail from FIG. 1, in which the tempering channel 16 can be seen particularly well. By this Temperierungskanal 16 or the passage of the Temperierungskanals 16 with a gas, for example

Compressed air, overheating of a nearby probe can be avoided if necessary. In the example shown, the tempering channel 16 is formed by three adjacent annular elements, the first annular element 9, the second annular element 10 and the third annular element 11. These have respective recesses, which in an assembly of the elements to form the Temperierungskanals 16 lead. Compared to the outer space and the measuring pocket 3, the temperature control channel 16 is sealed by two seals 15 between the first and second annular elements 9, 10 and the first and third annular elements 9, 11. In the example shown, the temperature control channel 16 is better than the second side 6 of Separator 4 closer than the first page 5 of the

Detecting separator 4. Thus, the cooling will be done mainly on the messtaschenabgewandten side of the sample holder 1.

In the example shown, the supply device 7 is fluidically coupled to the temperature control channel 16. The Temperierungskanal 16 is here so part of the supply device. This coupling can be done by a simple bore or recess and is not shown in FIG. If the tempering channel 16 flows through a gas, this gas can absorb heat from the measuring element 3 adjacent to the annular elements 9, 12. In general terms, the temperature control channel 16 can dissipate heat, which is transferred from the measuring pocket 3 to the housing 2 and is not desirable there.

Claims

claims

1. sample holder (1) for a measuring device for the contactless measurement of a dust sample, with a measuring housing (3) surrounded by a housing (3) for receiving the dust sample, and with a in the housing (2) embedded separating element (4), whose first side (5) faces the measuring pocket (3) and its opposite second side (6) faces the measuring device,

characterized in that

the sample receptacle (1) comprises at least one supply device (7) for guiding a fluid, by means of which the sample receptacle (1) can be cleaned of dust and / or specifically temperature-controlled.

2. Sample receiver (1) according to claim 1, characterized in that the supply device (7) has at least one outlet opening (8) which couples the supply device (7) fluidically with the measuring pocket (3) and in the direction of the first side (5). of the separating element (4) has, so that the first side (5) of the separating element (4) with a fluid flow from the outlet opening (8) can be acted upon.

3. sample holder (1) according to claim 2, marked thereby, that the outlet opening (8) has the shape of a fan slot.

4. Sample holder (1) according to one of the preceding claims, characterized in that the housing (2) has at least two concentric annular elements (9, 10, 11, 12) and the supply device (7) and / or the Aus - Entrance opening (8) at least partially by surfaces and / or recesses in the surfaces of adjacent annular elements (9, 10, 11, 12) are formed, wherein in particular one of the annular elements (9, 10, 11, 12), the separating element ( 4) encloses.

5. sample holder (1) according to claim 4, characterized in that the outlet opening (8) and / or the supply device (7) has at least two non-parallel surfaces of two adjacent annular elements (9, 10, 11, 12).

6. sample holder (1) according to one of claims 2 to 5, characterized in that a plurality of outlet openings (8), in particular 6 or in particular more than 6, are arranged in a circle around the separating element (4).

7. sample holder (1) according to any one of the preceding claims, characterized in that the supply device (7) at least partially around the separating element (4) runs around.

8. sample holder (1) according to any one of the preceding claims, characterized in that a part of the supply device (7) extends annularly around the separating element (4) and in particular the annular part of the supply device (7) of the second side (6) of the separating element ( 4) is closer than the first page (5).

9. A method for operating a sample holder (1) for a measuring device for measuring a dust sample, in which a

Dust sample in one of a housing (2) surrounded measuring pocket (3) is received and then by a in the housing (2) recessed separating element (4), the first side (5) of the measuring pocket (3) and its opposite second side (6 ) is facing the measuring device, is analyzed by the measuring device,

characterized in that

the sample receptacle (1) is specifically temperature-controlled by means of a fluid passed through at least one supply device (7) and / or cleaned, in particular before and / or after the analysis of dust.

10. The method according to claim 9, characterized by applying to the first side of the separating element (4) with a, in particular laminar, flow of the fluid through an outlet opening (8), which the supply device (7) fluidly with the measuring pocket (3). coupled.