Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
  • G01K17/00—Measuring quantity of heat
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N25/00—Investigating or analyzing materials by the use of thermal means
  • G01N25/20—Investigating or analyzing materials by the use of thermal means by investigating the development of heat, i.e. calorimetry, e.g. by measuring specific heat, by measuring thermal conductivity
  • G01N25/22—Investigating or analyzing materials by the use of thermal means by investigating the development of heat, i.e. calorimetry, e.g. by measuring specific heat, by measuring thermal conductivity on combustion or catalytic oxidation, e.g. of components of gas mixtures
  • G01N25/26—Investigating or analyzing materials by the use of thermal means by investigating the development of heat, i.e. calorimetry, e.g. by measuring specific heat, by measuring thermal conductivity on combustion or catalytic oxidation, e.g. of components of gas mixtures using combustion with oxygen under pressure, e.g. in bomb calorimeter
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
  • B01L2300/00—Additional constructional details
  • B01L2300/14—Means for pressure control

Definitions

• the invention relates to a calorimeter for determining the calorific value of a sample, wherein the calorimeter ter a Druckbenzol and arranged in the pressure vessel AufBank matters nis for receiving the sample.
• Calorimeters are previously known from the prior art and practice in different embodiments. Calorimeters are used to determine the calorific value of a sample. It is ignited in a conventional manner, a sample with means of an igniter of the calorimeter in the on-conclusion container. For this purpose, the sample is first placed in the digestion container and then generates an oxygen atmosphere within the digestion container. By activation of the igniter, the sample is then burned within the digestion vessel.
• the resulting heat is released via the digestion container to a liquid, usually water, with which the pressure vessel is filled and surrounding the digestion container. Knowing the amount of liquid, the heat capacity and the temperature, which receives the liquid in the pressure vessel by burning the sample in the digester, the calorific value of the sample can be determined.
• the pressure vessel are usually checked after a certain number kalo rimetrischer measuring operations and possibly exchanged out, for example, if damage should be detected.
• the Pressure vessels must be checked for safety reasons after one thousand calorimetric measuring processes and replaced if necessary. This can negatively affect the handling of the calorimeter.
• the object of the invention is therefore to provide a calorimeter of a type initially described, the handling is simplified and a needs-based test and, if appropriate, a needs-based replacement of Druckbereheatl age allowed.
• the Kalori meter has a strain gauge, which is at least indirectly disposed on the pressure vessel and with which a pressure-induced deformation of the pressure vessel can be determined.
• a strain gauge which is at least indirectly disposed on the pressure vessel and with which a pressure-induced deformation of the pressure vessel can be determined.
• at least one strain gauge in addition to a pressure-induced deformation of the pressure vessel at least indirectly or indirectly also within the Druckbenzol age fitting pressure can be determined with the at least one strain gauge.
• the pressure vessel can be monitored during a calorim cal measurement. Due to a pressure-related deformation of the pressure vessel can be deduced at least indirectly on the applied pressure in the pressure vessel. Once a maximum allowable pressure in the container and / or a maximum allowable deformation of the container has been exceeded, in which damage to the pressure vessel is to be feared, it can be determined that further use of the pressure vessel Ver is inadmissible on the calorimeter and a test and, where appropriate, an exchange of the printing containers are required.
• the calorimeter has a shutdown, the Be use and / or re-use of the calorimeter and in particular special of the pressure vessel at, in particular with the at least one strain gauge, detected overload of the pressure vessel and / or exceeding a Pressure limit value and / or prevented when detected inadmissible deformation of the pressure vessel.
• This shutdown device may be connected to the at least one strain gauge and output a blocking signal in response to a corresponding signal of the at least one strain gauge, which prevents the game to play a further ignition of an ignition device of Kalori.
• the shutdown device may be part of a control unit of the calorimeter or signal-technically connected to a control unit of the calorimeter.
• a particular advantage of the invention calorimeter be is that with the help of at least one strain gauge strip without great effort and a plastic deformation of the pressure vessel can be determined. Once a plastic deformation of a pressure vessel using the we least one strain gauge is determined, it can be determined that the plastically deformed pressure vessel for further use in further calorimetric Measurements is no longer suitable. Previously, a plastically deformed pressure vessel should first be checked at least on its further capacity out and possibly even exchanged.
• the calorimeter according to the invention thus offers the possibility of carrying out the test and, if appropriate, the replacement of pressure vessels as needed, and not after a certain number of calorimetric measuring operations, whether an actual overloading of the pressure vessel has not yet taken place.
• the calorimeter according to the invention has at least one strain gauge the advantage that not even a concrete pressure limit, which must not be exceeded, must be specified. Once an un permissible deformation, for example, a plastic deformation of the pressure vessel using the at least one strain gauge was determined strip, the pressure vessel should be checked and replaced if necessary.
• one, for example, the previously mentioned, shutdown and / or a control unit of Kalorime age prevent further operation of the calorimeter with the inadmissible or permanently deformed pressure vessel.
• the at least one strain gauge used for pressure determination may be arranged on an outer side of the pressure vessel facing away from the digestion vessel. In this way, the strain gauges do not come into direct contact with the liquid filled in the pressure vessel during operation of the calorimeter and thus do not have to be particularly exposed to liquid. W MPACT be protected.
• the at least one strain gauge used to determine a deformation of the pressure vessel and at least for indirect pressure determination may preferably be arranged directly on the pressure vessel.
• a pressure-related deformation of the pressure vessel can be transmitted to the at least one strain gauge particularly easily and reliably.
• the strain gauge is not un indirectly arranged on the pressure vessel, but rather on a holder which is connected to the pressure vessel such that a mechanical load on the holder, which is caused by a mechanical and pressure-induced stress of the pressure vessel , Can also be transmitted to the at least one used for Druckbe mood strain gauges.
• a holder may for example be a holding plate.
• the at least one strain gauge is arranged at a location on the pressure vessel at which preferably experiences a pressure-induced stress and / or deformation.
• the at least one strain gauge can be arranged on an outer underside of the pressure vessel particularly well protected.
• it can be arranged as close as possible to, for example, a control unit and / or a Abschaltvor direction of the calorimeter.
• the at least one strain gauge can be well protected against external influences, which can minimize the risk of its damage.
• the calorimeter may further comprise a measuring circuit which is adapted to compensate for a temperature error of the at least one strain gauge, which is used to determine a deformation of the pressure vessel and for indirect pressure determination.
• a measuring circuit which is adapted to compensate for a temperature error of the at least one strain gauge, which is used to determine a deformation of the pressure vessel and for indirect pressure determination.
• the strip at least one strain gauge may be subject to a temperature error, which may distort a correct determination of the deformation of the pressure vessel and / or the pressure inside the pressure vessel.
• This measuring circuit for temperature compensation can Wheatstone see 'bridge circuit may be formed.
• the measuring circuit may have at least one further strain gauge in addition to the at least one strain gauge used to determine the deformation of the pressure vessel and the at least indirect pressure determination. This at least one further strain gauge can be referred to as a temperature compensation strain gauge.
• the at least one temperature compensation strain gauge is preferably connected to the pressure vessel in such a way that heat transfer from the pressure vessel to this at least one temperature compensation strain gauge takes place without the at least one temperature compensation strain gauge applying a pressure-related stress and / or pressure Length change due to its contact with the pressure vessel experiences.
• the measuring circuit may be designed such that it strips due to the arrangement of the total of at least two strain gauges in the measuring circuit as a result of a value that only the pressure inside the pressure vessel and / or associated with this pressure deformation of the Represents pressure vessel.
• the previously mentioned measuring circuit can be realized particularly simply if the strain gauge used for determining the deformation of the pressure vessel and / or for determining the pressure is at least one strain gauge and the at least one second strain gauge or temperature compensation strain gauge of the measuring circuit is identical strain gauges.
• this first strain gauge is subject to a Tem peraturcloud due to its inevitably occurring heating, which can also be referred to as a temperature-related drift of the strain gauges.
• This temperature error may be due to a temperature-induced change in electrical resistance and / or a length of the strain gauges. This is especially true if the strain gauge is an electrical or electronic Deh voltage gauge.
• the use of optical strain gauges as at least one strain measuring strip for determining a deformation of Druckbenzol age and / or for pressure determination is conceivable.
• the temperature error of the measured value determined by the first strain gauge can be compensated. This is particularly easy if the total of at least two strain gauges are identical strain gauges.
• the measuring circuit can be designed as a bridge circuit, in which both strain gauges are integrated.
• the measuring circuit is designed so that the compensation of the temperature error of the at least one for pressure determination before seen strain gauge is done automatically and can output an output from the measuring circuit reading directly on the mechanical cal load of the pressure vessel and the pressure inside the pressure vessel.
• the pressure vessel consists of a particularly thermally conductive material, for example aluminum.
• the calorimeter inside the container can have at least one temperature sensor.
• the calorimeter has a control unit.
• This control unit can be signal-technically connected to the previously mentioned shutdown device and / or have such a device.
• the control unit may be formed from such that it prevents operation of the calorimeter at a detected with the at least one strain gauge and / or with the measuring circuit inadmissible, for example plastic, deformation of the pressure vessel.
• the pressure vessel may have an inlet. Be particularly advantageous may be when the pressure vessel except the one overflow, in which a liquid sensor is ordered to. In this way it is possible to fill the pressure vessel via the inlet with liquid. This happens at least until the liquid sensor in the overflow of the pressure vessel comes into contact with liquid. As soon as the liquid sensor detects liquid in the overflow of the pressure vessel, a complete filling of the pressure vessel with liquid can be assumed.
• a complete filling of the pressure vessel with liquid is advantageous on the one hand for accurate calorimetric measurement and on the other hand for safety reasons. If there is a residual amount of air or gas inside the pressure vessel, there is less liquid in the pressure vessel than in a completely filled pressure vessel. The smaller amount of liquid in the only partially filled pressure vessel has a lower overall heat capacity. If this is not taken into account in the calorimetric measurement, a precise determination of the calorific value of the sample burned in the digestion container can not be carried out.
• the calorimeter Due to the possible in a calorimetric measurement pressure increase inside the pressure vessel and a Kompri mieronia of air in the pressure vessel, it may also come to the Ent empty the pressure vessel to pressure surges. These can, on the one hand, affect the comfortable handling of the calorimeter and, on the other hand, pose a safety risk. It can be advantageous if the calorimeter has an information output device, in particular a display device, via which information relating to a calorimetric measurement and / or a state of the calorimeter, in particular its pressure vessel, can be output.
• an information output device in particular a display device
• acoustic and / or visual information relating to a pressure value determined with the at least one strain gage and / or measuring circuit, a temperature value of the fluid in the pressure vessel, a deformation of the pressure vessel, proper filling of the pressure vessel of the calorimeter, and / or this information output device can be output via this information output device. or a determined calorific value of a sample.
• a particular aspect of using a strain gauge as an indirect pressure sensor to the pressure vessel can be seen that in a plastic deformation of the pressure vessel, ie at a deformation that remains at degradation of the pressure, the strain gauge due to its associated with the plastic deformation mechanical Be loadung continues to output a corresponding signal.
• the use of the at least one provided for pressure determination strain gauge on the pressure vessel has in to sammenspiel with the temperature sensor of the calorimeter another advantage.
• a pressure increase inside the pressure vessel is caused.
• the pressure increase and thus the ignition of the sample can be detected at the pressure vessel with the help of the at least one strain gauge provided for pressure determination.
• Tem perature rise inside the pressure vessel after a certain time this may indicate a malfunction or maloperation of the calorimeter and here in particular a circulating device of the calorimeter, which can take a stirrer or magnetic stirrer with a stirring magnet around.
• the calorimeter according to the invention has another advantage: Often the digestion container is only loosely closed, for example, by a sleeve-like hood, which is placed on a base plate of the digestion container. If the digestion vessel is not properly closed, part of the oxygen atmosphere introduced into the digestion vessel prior to the ignition of the sample may enter the pressure vessel from the digestion vessel. This can lead to a pressure increase. Before combustion of the sample, the digestion container can be filled under pressure with the oxygen atmosphere, for example at a pressure of 30 ⁇ 10 5 Pa.
• this leakage can be determined at least indirectly by means of the strain gauge.
• the overpressure still present in the digestion ratio is released by discharging the atmosphere contained in the digestion receptacle to ambient pressure. If, with the aid of the strain gauge on the pressure vessel, after the excess pressure has been released from the digestion ratio, a pressure can still be ascertained which is higher than the ambient pressure, it is to be feared that part of the oxygen atmosphere from the digestion vessel has previously entered the pressure vessel.
• the pressure vessel of the calorimeter should not be opened by an operator himself, but only by the authorized service partner.
• the core aspect of the calorimeter according to the invention can be summarized as follows:
• the invention is concerned with improvements in the technical field of calorimetry.
• the calorimeter according to the invention which has the pressure vessel, which is provided with at least one strain gauge. This with the aim of a deformation of the pressure vessel when performing calorimetric measurements. This makes it possible to monitor a load on the pressure vessel and, moreover, at least indirectly, to close it back to an internal pressure present in the pressure vessel.
• the single figure shows a highly schematic of a sectional view of a calorimeter with a two-part pressure vessel and a angeord Neten digestion vessel in which a sample can be burned under oxygen atmosphere.
• the calorimeter 1 shows a calorimeter designated as a whole by 1 for determining the calorific value of a sample 4.
• the calorimeter 1 has a pressure vessel 2 and an in the pressure vessel 2 to ordered decomposition vessel 3.
• the digestion container 3 serves to receive the sample 4 to be incinerated.
• the digestion container 3 is filled with oxygen, which forms an oxygen atmosphere 6 in the digestion container 3.
• This oxygen atmosphere 6 may have an overpressure of, for example, 30 bar in relation to the ambient pressure.
• the sample 4 is ignited by means of the ignition device 5.
• the resulting heat is given via the digestion container 3 to a liquid, namely to a water bath 7, in the interior of the pressure vessel 2 at. Heating of the water bath 7 is measured and from this the calorific value of the sample 4 is determined.
• the calorimeter 1 has a strain gauge 8, which is arranged on the pressure vessel 2 and with the pressure-induced deformation of the pressure vessel 2 and thus indirectly can be determined within the pressure vessel 2 adjacent pressure.
• the outer side 9 of the pressure vessel 2 is that side of the pressure vessel 2, which faces away from the digestion vessel 3 in the interior of the pressure vessel 2.
• the strain gauge 8 is so arranged directly on the outer side 9 of the pressure vessel 2 and in front lying embodiment, in addition to a lower part 2 a of the pressure vessel 2 that a pressure-related For modification of the pressure vessel 2 can be transmitted directly and directly to the strain gauges 8.
• the lower part 2a of the pressure vessel 2 is pressure-tightly connected via a flange 2b to an upper part 2c of the pressure vessel 2.
• the strain gauge 8 is well protected and arranged within a housing 1a of the calorimeter 1, which is indicated only in a very highly schematic manner.
• the calorimeter 1 has a measuring circuit 10, which is part of a pressure measuring system. With the aid of the measuring circuit 10, a temperature error of Deh used for determining a change in shape of the pressure vessel 2 and thus for pressure determination DungsmessstMails 8 can be compensated.
• the measuring circuit 10 comprises the vorgese for determining pressure henen strain gauge 8 and a second strain gauge strip 11, which serves to compensate for the temperature error and therefore can also be referred to as a temperature compensation strain gauges 11.
• the second strain gauge 11 is connected to the pressure vessel 2 such that a Heat transfer from the pressure vessel 2 to this second strain gauge 11 is carried out without the second strain gauge 11 experiences a pressure-induced stress and / orPartnän change.
• the measuring circuit 10 is directed to the output of a measured value, which represents the pressure in the pressure vessel 2.
• the two strain gauges 8 and 11 are identical strain gauges, so that the heat-related change of the properties of the strain gauge 8 and a potentially associated falsification of the pressure reading determined by it by the identically responsive strain gauges 11 and its isolated considered heat-related change can be easily compensated.
• the pressure vessel 2 is made of a good thermal conductivity material, for example made of aluminum.
• the aim in the design of the Druckbe container 2 is that the two forcibly arranged at under defenceli Chen locations strain gauges 8 and 11 of the measuring circuit 10 are heated in the same way. It has proved to be advantageous if the pressure vessel 2 consists of the good thermal conductivity material, for example of aluminum. Thus, a homogeneous heating of the two different locations where the two strain gauges 8 and 11 are arranged, can be achieved. This can promote an accuracy of the temperature compensation in the determination of the deformation of the pressure vessel 2 and / or in the pressure determination of the pressure in the pressure vessel 2 pressure using the strain gauges 8.
• the calorimeter 1 has a temperature sensor 14 arranged inside the pressure vessel 2. With the help of this temperature sensor 14, the heating of the water bath 7 can be measured within the pressure vessel 2 when burning the sample 4 and the calorimetric measurement can be performed.
• the measuring circuit 10 of the calorimeter 1 may be connected to a control unit 18 of the calorimeter 1 such that the control unit 18 prevents operation of the calorimeter 1 at a detected with the at least one strain gauge 8 and / or with the measuring circuit 10 plastic deformation of the pressure vessel 2 ,
• the Steuerein unit 18 includes a shutdown device 18a, which deactivates the calorimeter 1 at detected overload of the pressure vessel 2 and prevents further use of the calorimeter 1 with the same pressure tank 2.
• the pressure vessel 2 of the calorimeter 1 has an inlet 12. About this inlet 12 of the pressure vessel 2 with liq fluid, here filled with the water bath 7. Via an overflow 13, which is provided at the inlet 12 opposite the upper end of the pressure vessel 2, the filled into the pressure vessel 2 liquid at complete filling of the pressure vessel 2 can escape again.
• a liquid sensor 13a is arranged in the overflow 13, a liquid sensor 13a is arranged.
• a further liquid sensor 12a is provided in the inlet 12.
• the two liquid sensors 12a and 13a can be determined when a filling of the pressure vessel 2 begins with liquid.
• the liquid sensor 12a arranged in the inlet 12 comes into contact with liquid, it emits a corresponding signal.
• the pressure vessel 2 fills with liquid. This is continued until the liquid sensor 13a arranged in the overflow 13 of the pressure vessel 2 comes into contact with liquid and likewise outputs a corresponding signal which can be correspondingly processed by the control unit 18 of the calorimeter 1.
• the second liquid sensor 13a comes into contact with liquid in the overflow 13 of the pressure vessel 2, a proper and complete filling of the calorimeter 1 with liquid can be deduced.
• the calorimeter 1 further includes an information output device 19.
• This can be designed as an optical display device and / or as an acoustic signal device.
• This information output device 19 can example, a circuit with the strain gauges 8 and / or with the measuring 10 certain pressure value, a temperature value and / or proper filling of the pressure vessel 2 to a loading user output. It is of course also possible to provide further information that might be of interest to the user of the calorimeter 1.
• the digestive container 3 can be filled to produce the oxygen atmosphere 6 with oxygen. This happens, for example, with a pressure of 30 ⁇ 10 5 Pa.
• the sample 4 is set afire by means of the ignition device 5.
• the calorimeter 1 is equipped with a stirring device. This stirring device comprises a provided outside the pressure vessel 2 Stirrantrieb 17.
• Stirring element 16 is disposed in the interior of the pressure vessel 2 and ensures during operation of the stirrer 17 for a corresponding circulation of the water bath 7 and thus for a homo gene as possible Distribution of the heat in the interior of the pressure vessel 2.
• the heat emitted by the sample 4 during its combustion and the associated He increase the temperature of the water bath 7 can then be determined and the calorimetric measurement can be performed.
• the invention is concerned with improvements in the technical field calorimetry.
• a calorimeter 1 which has a pressure vessel 2, which is provided with at least one strain gauge 8. This with the aim of measuring a deformation of the pressure vessel 2 in the performance of calorimetric measurements and thus at least indirectly infer a lying in the pressure vessel 2 to internal pressure.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Combustion & Propulsion (AREA)
• General Physics & Mathematics (AREA)
• Physics & Mathematics (AREA)
• Life Sciences & Earth Sciences (AREA)
• Health & Medical Sciences (AREA)
• Analytical Chemistry (AREA)
• Biochemistry (AREA)
• General Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Immunology (AREA)
• Pathology (AREA)
• Investigating Or Analyzing Materials Using Thermal Means (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=65576360

Family Applications (1)

Country Status (5)

Family Cites Families (21)

• 2018
  • 2018-02-26 DE DE102018104327.9A patent/DE102018104327B4/de active Active
• 2019
  • 2019-02-25 US US16/975,424 patent/US20210109048A1/en active Pending
  • 2019-02-25 WO PCT/EP2019/054626 patent/WO2019162512A1/de unknown
  • 2019-02-25 CN CN201980015163.8A patent/CN111788466A/zh active Pending
  • 2019-02-25 EP EP19707773.8A patent/EP3759447A1/de not_active Withdrawn

Also Published As

Similar Documents

Legal Events