CN112461884A - Nano powder dispersing method and device based on ion flow control - Google Patents
Nano powder dispersing method and device based on ion flow control Download PDFInfo
- Publication number
- CN112461884A CN112461884A CN202011416511.3A CN202011416511A CN112461884A CN 112461884 A CN112461884 A CN 112461884A CN 202011416511 A CN202011416511 A CN 202011416511A CN 112461884 A CN112461884 A CN 112461884A
- Authority
- CN
- China
- Prior art keywords
- voltage
- nano
- probes
- electric field
- minimum ignition
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- 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
- G01N25/02—Investigating or analyzing materials by the use of thermal means by investigating changes of state or changes of phase; by investigating sintering
- G01N25/12—Investigating or analyzing materials by the use of thermal means by investigating changes of state or changes of phase; by investigating sintering of critical point; of other phase change
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F33/00—Other mixers; Mixing plants; Combinations of mixers
- B01F33/05—Mixers using radiation, e.g. magnetic fields or microwaves to mix the material
-
- 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
- G01N25/50—Investigating or analyzing materials by the use of thermal means by investigating flash-point; by investigating explosibility
- G01N25/54—Investigating or analyzing materials by the use of thermal means by investigating flash-point; by investigating explosibility by determining explosibility
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
- G01R29/12—Measuring electrostatic fields or voltage-potential
- G01R29/14—Measuring field distribution
Landscapes
- Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Physical Or Chemical Processes And Apparatus (AREA)
Abstract
The invention discloses a nano powder dispersing method based on ion flow control, a nano dust cloud minimum ignition energy dispersing device based on the method and a nano dust cloud minimum ignition temperature dispersing device based on the method. The method comprises the steps of measuring electric field vector distribution in a test space, calculating the change relation of the vector electric field distribution along with time, and controlling the polarity, flow and duration of ion current output by the ion current generating unit according to the relation, so that the quantity of generated positive and negative ions is neutralized with the quantity of electric charge generated in the dispersion process of the nano powder, and the nano powder is prevented from agglomerating in the dispersion process. The invention can realize the uniform dispersion of the nano-grade dust, and the measurement of the minimum ignition energy and the minimum ignition temperature of the nano-powder is more accurate.
Description
Technical Field
The invention relates to a nano powder dispersing method and device based on ion flow control, which are mainly applied to the dust dispersing process of dust explosion characteristic parameter testing instruments such as a dust cloud minimum ignition energy tester, a dust cloud minimum ignition temperature tester and the like, prevent dust from forming dust particle aggregates in the dispersing process, realize uniform dispersion of nano powder and enable the measuring result of dust explosion characteristic parameters to be more accurate.
Background
The minimum ignition energy and the minimum ignition temperature are important parameters for evaluating the explosion risk of the dust. With the wide application of nano powder in the fields of medicine, electronics, chemical industry, military and the like, the measurement of dust explosion characteristic parameters such as the minimum ignition energy and the minimum ignition temperature of the nano powder is urgently required to be realized. In the dust explosion characteristic parameter test, dust to be tested is uniformly dispersed in a test device under a certain pressure to form dust cloud, and then a sample to be tested is ignited by a certain energy or a certain temperature to obtain corresponding test parameters. However, compared to micron-sized dust, nano-sized dust, i.e. nano-powder, is more likely to agglomerate during the dispersion process due to the acting force between molecules and the electrostatic attraction between particles, forming larger particles. The particle size distribution of the dust is an important influence factor of dust explosion characteristic parameters such as the minimum ignition energy and the minimum ignition temperature of combustible dust, and generally, the smaller the particle size of the dust is, the larger the specific surface area of the dust is, and the smaller the required minimum ignition energy and the required minimum ignition temperature are. After the nano powder is agglomerated, the particle size distribution of the nano powder is increased, so that the measured values of the parameters of the combustion and explosion characteristics such as the minimum ignition energy, the minimum ignition temperature and the like are larger. The minimum ignition energy, the minimum ignition temperature and other explosion characteristic parameter values are directly related to the danger level of the dust to be measured, and if the measured explosion characteristic parameter values are larger, the danger rating is lower, so that immeasurable serious hidden danger is brought.
The current explosion characteristic parameter testing instruments such as a dust cloud minimum ignition energy tester, a dust cloud minimum ignition temperature tester and the like are designed aiming at micron-sized dust, and the agglomeration phenomenon generated in the dispersion process of the micron-sized dust is far lower than that of the nanometer-sized dust. Therefore, the current explosion characteristic parameter testing instrument cannot realize accurate measurement of the explosion characteristic parameters of the nano powder, which brings difficulty to the risk grading of the nano powder.
Disclosure of Invention
In view of the above problems, an object of the present invention is to provide a method and an apparatus for dispersing nano-powder based on ion flow control, which are used to prevent the nano-dust from agglomerating during the dispersion process, improve the uniformity of dust dispersion, and further achieve accurate measurement of the blasting characteristic parameters of the nano-powder.
In order to achieve the above objects, according to one aspect of the present invention, there is provided a nano-scale dust cloud minimum ignition energy dispersing apparatus, including a static electricity sensitive probe, a measuring and controlling unit, a compressed air controlling unit, an ion current generating unit, and a hartmann tube.
The electrostatic sensing probe adopts an induction type electrostatic sensing probe, a rotary type electrostatic sensing probe or a vibration capacitance type electrostatic sensing probe and is used for measuring the distribution of the vector electric field in the Hartmann tube. The electrostatic sensitive probes are arranged in four pairs, each pair of probes is a pair, each pair of probes is positioned on the same horizontal shaft and fixed on two sides of the Hartmann tube wall, the two pairs of probes are positioned at different heights, and the central axes where the two pairs of probes are positioned are orthogonal. The output end of the static sensitive probe is connected to the measurement and control unit.
The measuring and controlling unit converts the charge signal measured by the electrostatic sensitive probe into a voltage signal, calculates the electric field vector distribution in the Hartmann tube according to the voltage signal, and controls the polarity, the flow and the duration of the ion current output by the ion current generating unit according to the electric field vector distribution.
Wherein the compressed air control unit includes: a silent air compressor which provides compressed air with certain pressure; the output end of the mute air compressor is connected to the input end of the filter, so that oil mist separation and filtration of compressed air are realized; the output end of the filter is connected to the input end of the pressure reducing valve, and the pressure reducing valve reduces the system pressure to be within an allowable range; the output end of the pressure reducing valve is connected to the input end of the air inlet electromagnetic valve, and the air inlet electromagnetic valve is controlled by an electric signal and is used for automatically controlling air inflow; the output end of the air inlet electromagnetic valve is connected to the input end of the air storage container, and a pressure sensor is arranged in the air storage container and used for monitoring the air pressure of the air storage container in real time so as to realize automatic control of the air input quantity of the compressed air; the output end of the air storage container is connected to the input end of the air exhaust electromagnetic valve, the output end of the air exhaust electromagnetic valve is connected to the air inlet of the Hartmann tube through an air tube, and the air exhaust electromagnetic valve is controlled by an electric signal and can realize remote control or automatic control.
Wherein the ion current generating unit includes: the high-voltage power supply provides a direct-current output voltage in the range of minus 10kV to plus 10kV, and parameters of the polarity, the amplitude, the discharge duration and the like of the direct-current output voltage are controlled by the measuring unit; the high-voltage capacitor is used for providing energy storage for the high-voltage power supply; the electrode needle is arranged in an air pipe connected from the output end of the exhaust electromagnetic valve to the air inlet of the Hartmann pipe, the output of the high-voltage power supply is connected to the high-voltage electrode, the ground of the high-voltage power supply is connected to the ground electrode, and the high-voltage electrode and the ground electrode are coaxial and are spaced at a certain distance.
The Hartmann tube comprises a powder storage chamber, a disperser and a quartz glass tube, and is a common device in the field and is not described herein again.
As another aspect of the invention, the invention also provides a nanoscale dust cloud minimum ignition temperature dispersing device which comprises a measuring and controlling unit, a compressed air controlling unit, an ion flow generating unit and a Gaderger-Gerunval furnace.
The electrostatic sensing probe can adopt an induction type electrostatic sensing probe, a rotary type electrostatic sensing probe or a vibration capacitance type electrostatic sensing probe and is used for measuring the distribution of the vector electric field in the Gaoergt-Gerovadel furnace. The electrostatic sensitive probes are arranged in four, each two probes are positioned on the same horizontal shaft and close to two sides of the pipe wall of the Boerger-Gerun Wald furnace, the two pairs of probes are positioned at different heights, and the central axes where the two pairs of probes are positioned are orthogonal. The output end of the static sensitive probe is connected to the measurement and control unit. Unlike the nano-scale minimum ignition energy dispersing device for dust cloud, the electrostatic sensing probe cannot be fixed in the Burger-Geroval furnace because the temperature in the Burger-Geroval furnace is as high as 1000 ℃. The static sensitive probe of the nanoscale dust cloud minimum ignition temperature dispersing device is movable, and only when a new sample to be tested is tested, the static sensitive probe is placed in the high-power Burger-Geroval furnace, and the furnace body is not heated, so that the vector electric field distribution of the new sample to be tested in the high-power Burger-Geroval furnace is tested.
The measuring and controlling unit converts the charge signal measured by the electrostatic sensitive probe into a voltage signal, calculates the electric field vector distribution in the Burger-Gerward furnace according to the voltage signal, and controls the polarity, flow and duration of the ion flow output by the ion flow generating unit according to the electric field vector distribution.
Wherein the compressed air control unit includes: a silent air compressor which provides compressed air with certain pressure; the output end of the mute air compressor is connected to the input end of the filter, so that oil mist separation and filtration of compressed air are realized; the output end of the filter is connected to the input end of the pressure reducing valve, and the pressure reducing valve reduces the system pressure to be within an allowable range; the output end of the pressure reducing valve is connected to the input end of the air inlet electromagnetic valve, and the air inlet electromagnetic valve is controlled by an electric signal and is used for automatically controlling air inflow; the output end of the air inlet electromagnetic valve is connected to the input end of the air storage container, and a pressure sensor is arranged in the air storage container and used for monitoring the air pressure of the air storage container in real time so as to realize automatic control of the air input quantity of the compressed air; the output of the air storage container is connected to the input end of the air exhaust electromagnetic valve, and the air exhaust electromagnetic valve is controlled by an electric signal and can realize remote control or automatic control; and the output end of the exhaust electromagnetic valve is connected to the input end of the powder storage chamber, the output end of the powder storage chamber is connected to an inlet above the high-yield Burger-Gerwell furnace through a glass tube, and the powder storage chamber is used for containing nano powder.
Wherein the ion current generating unit includes: the high-voltage power supply provides a direct-current output voltage in the range of minus 10kV to plus 10kV, and parameters of the polarity, the amplitude, the discharge duration and the like of the direct-current output voltage are controlled by the measuring unit; the high-voltage capacitor is used for providing energy storage for the high-voltage power supply; the electrode needle is arranged in a glass tube connected with the output end of the powder storage chamber to the air inlet of the high-gain Boerger-Geroval furnace, the output of the high-voltage power supply is connected to the high-voltage electrode, the ground of the high-voltage power supply is connected to the ground electrode, and the high-voltage electrode and the ground electrode are coaxial and are spaced at a certain distance.
The high-grade Burger-Gerovader furnace comprises a quartz glass tube and a heating wire, and is a common device in the field and is not described again.
As another aspect of the present invention, the present invention further provides a method for dispersing a nano powder based on ion flow control, comprising the steps of:
measuring the electric field vector distribution in the quartz glass tube, calculating the change relation of the vector electric field distribution along with time, and controlling the polarity, flow and duration of the ion current output by the ion current generating unit according to the relation to neutralize the quantity of generated positive and negative ions and the quantity of electric charge generated in the dispersion process of the nano powder, thereby preventing the nano powder from agglomerating in the dispersion process and realizing the uniform dispersion of the nano dust.
The invention has the beneficial effects that: by controlling the polarity, flow and duration of ion flow, the positive and negative ion quantity adaptive to the charge quantity caused by friction in the dispersion process of the nano powder is generated, the nano powder is prevented from forming aggregates in the dispersion process, and the uniform dispersion of the nano-grade dust is realized, so that the measurement of the minimum ignition energy and the minimum ignition temperature is more accurate.
Drawings
FIG. 1 is a schematic illustration of a nanoscale dust cloud with minimal ignition energy, in accordance with an embodiment of the present invention.
Fig. 2 is a plan view of arrangement of the electrostatic sensing probe in the hartmann tube apparatus.
FIG. 3 is a schematic diagram of the minimum ignition temperature of a nano-sized dust cloud according to an embodiment of the present invention.
Fig. 4 is a top view of the arrangement of the electrostatic sensing probe in a high-grade berg-grunbard furnace apparatus.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to specific embodiments and the accompanying drawings. It should be noted that in the drawings or description, the same drawing reference numerals are used for similar or identical parts. Implementations not depicted or described in the drawings are of a form known to those of ordinary skill in the art.
In one exemplary embodiment of the present invention, a nano-sized dust cloud minimum ignition energy dispersing apparatus based on an ion flow controlled nano-powder dispersing method is provided. Referring to fig. 1, the nano-scale dust cloud minimum ignition energy dispersing device includes a static electricity sensitive probe, a measuring and controlling unit, a compressed air controlling unit, an ion current generating unit, and a hartmann tube.
The compressed air control unit includes: the mute air compressor 1 is used for providing compressed air with certain pressure; the output end of the mute air pressure 1 is connected to the input end of the filter 2, so that oil mist separation and filtration of the compressed air are realized; the output end of the filter 2 is connected to the input end of the pressure reducing valve 3 and is used for controlling the air inlet pressure of the air path; the output end of the pressure reducing valve 3 is connected to the input end of the electromagnetic valve 4, and the electromagnetic valve 4 is controlled by an electric signal and is used for automatically controlling the air inflow; the output end of the electromagnetic valve 4 is connected to the input end of the air storage container 6, the volume of the air storage container 6 is 50mL, and the air storage container 6 is externally provided with a pressure sensor 5 and used for monitoring the air pressure of the air storage container in real time so as to realize automatic control of the air input quantity of compressed air; the output end of the electromagnetic valve 7 is connected to the input end of the electromagnetic valve 7, the output end of the electromagnetic valve 7 is connected to the air inlet of the Hartmann tube through the air tube 12, and the electromagnetic valve 7 is controlled by an electric signal, so that remote control or automatic control can be realized.
The ion current generating unit includes: the high-voltage power supply 14 provides a direct-current output voltage within the range of minus 10kV to plus 10kV, and parameters of the direct-current output voltage, such as polarity, amplitude, discharge duration and the like, are controlled by the measurement and control unit; the high-voltage capacitor C is used for providing energy storage for a high-voltage power supply, and the value range of the high-voltage capacitor C is preferably 20-100 pF; an electrode needle 11 and an electrode needle 13 are arranged in the trachea 12, the output of a high-voltage power supply 14 is connected to the electrode needle 13, the ground of the high-voltage power supply 14 is connected to the electrode needle 11, and the electrode needle 11 and the electrode needle 13 are coaxial and are spaced at a certain distance. The material of the electrode needle 11 and the electrode needle 13 is preferably stainless steel or tungsten.
The electrostatic sensitive probes 15, 16, 17 and 18 are arranged on the inner wall of the Hartmann tube, the outputs of the electrostatic sensitive probes 15, 16, 17 and 18 are connected to the measurement and control unit, the measurement and control unit converts charge signals measured by the electrostatic sensitive probes into voltage signals, the electric field vector in the Hartmann tube is calculated according to the voltage signals, and the output of the high-voltage power supply 14 is controlled according to the electric field vector.
Referring to fig. 1 and 2, the arrangement positions of the electrostatic sensing probes are shown, the electrostatic sensing probes 15 and 16 are positioned on the same horizontal axis and fixed on two sides of the hartmann tube wall, the electrostatic sensing probes 17 and 18 are positioned on the same horizontal axis at another height and fixed on two sides of the hartmann tube wall, and the central axes of the two pairs of probes are orthogonal.
When the minimum ignition energy of the nano powder needs to be tested, the working steps of adopting the nano dust cloud minimum ignition energy dispersion device are as follows:
1) a pretesting process, namely placing the nano powder 19 in a powder storage chamber 8, turning off a high-voltage power supply 14, controlling a compressed air control unit to generate airflow with certain pressure, blowing up the nano powder 19 in the powder storage chamber 8, forming dust cloud in the quartz glass tube 10 after the nano powder 19 passes through a disperser 9, measuring output signals of the electrostatic sensitive probes 15-18 by a measuring and control unit, and calculating the change relation of a vector electric field in the quartz glass tube 10 along with time;
2) repeating the pretesting process in the step 1), and obtaining the variation relation of the average value of the measured vector electric field along with time, wherein the variation relation of the vector electric field distribution in the quartz glass tube 10 along with time is the variation relation of the electric charge generated by friction in the powder dispersing process, namely the variation relation of the electric charge generated by friction in the powder dispersing process along with time;
3) and (3) a normal testing process, namely placing the nano powder 19 in the powder storage chamber 8, turning on the high-voltage power supply 14, controlling the output voltage and polarity of the high-voltage power supply 14 according to the change relation of the average value of the vector electric field obtained in the step 2) along with time, further controlling the flow of ion current, controlling the compressed air control unit to generate airflow with certain pressure and containing positive and negative ions, blowing up the nano powder in the powder storage chamber, forming dust cloud in the quartz glass tube after the nano powder passes through the disperser, neutralizing the charge quantity generated by friction in the powder dispersing process by the positive and negative ions, and avoiding the agglomeration phenomenon of the nano powder in the dispersing process.
In another exemplary embodiment of the present invention, a nano-sized dust cloud minimum ignition temperature dispersing apparatus based on an ion flow controlled nano-powder dispersing method is provided. Referring to fig. 3, the apparatus includes a static electricity sensitive probe, a measuring and controlling unit, a compressed air controlling unit, an ion current generating unit, and a high-grade berg-grunbard furnace.
The compressed air control unit includes: the mute air compressor 1 is used for providing compressed air with certain pressure; the output end of the mute air pressure 1 is connected to the input end of the filter 2, so that oil mist separation and filtration of the compressed air are realized; the output end of the filter 2 is connected to the input end of the pressure reducing valve 3 and is used for controlling the air inlet pressure of the air path; the output end of the pressure reducing valve 3 is connected to the input end of the electromagnetic valve 4, and the electromagnetic valve 4 is controlled by an electric signal and is used for automatically controlling the air inflow; the output end of the electromagnetic valve 4 is connected to the input end of the air storage container 23, the volume of the air storage container 23 is 500mL, and the air storage container 23 is externally provided with a pressure sensor 5 for monitoring the air pressure of the air storage container in real time so as to realize automatic control of the air input quantity of the compressed air; the output end of the air storage container 6 is connected to the input end of the electromagnetic valve 7, the output end of the electromagnetic valve 7 is connected to the input end of the powder storage chamber 20, and the electromagnetic valve 7 is controlled by an electric signal and can realize remote control or automatic control; and the powder storage chamber 20 is used for containing the nano powder 19.
The ion current generating unit includes: the high-voltage power supply 14 provides a direct-current output voltage within the range of minus 10kV to plus 10kV, and parameters of the direct-current output voltage, such as polarity, amplitude, discharge duration and the like, are controlled by the measurement and control unit; the high-voltage capacitor C is used for providing energy storage for a high-voltage power supply, and the value range of the high-voltage capacitor C is preferably 20-100 pF; the electrode needle 11 and the electrode needle 13 are arranged in a connecting air pipe from the output end of the powder storage chamber 20 to the input end of the high-grade Burger-Gerward furnace, the output of a high-voltage power supply 14 is connected to the electrode needle 13, the ground of the high-voltage power supply 14 is connected to the electrode needle 11, and the electrode needle 11 and the electrode needle 13 are coaxial and are spaced at a certain distance. The material of the electrode needle 11 and the electrode needle 13 is preferably stainless steel or tungsten.
The Gaoerberg-Gerherward furnace consists of a quartz glass tube 21 and a heating wire 22, and the heating wire 22 surrounds the outer wall of the quartz glass tube 21 according to a certain rule.
The electrostatic sensitive probes 24, 25, 26 and 27 are arranged on the inner wall of the quartz glass tube 21, the outputs of the electrostatic sensitive probes 24, 25, 26 and 27 are connected to the measurement and control unit, the measurement and control unit converts the charge signals measured by the electrostatic sensitive probes into voltage signals, calculates the electric field vector in the Hartmann tube according to the voltage signals, and controls the output of the high-voltage power supply 14 according to the electric field vector.
As the temperature in the Gerotker furnace is as high as 1000 ℃, the arrangement positions of the electrostatic sensitive probes refer to fig. 3 and 4 for protecting the electrostatic sensitive probes, the electrostatic sensitive probes 24 and 25 are positioned on the same horizontal shaft and close to two sides of the inner wall of the quartz glass tube 21, the electrostatic sensitive probes 26 and 27 are positioned on the same horizontal shaft at another height and fixed on two sides of the inner wall of the quartz glass tube 21, and the central axes of the two pairs of probes are orthogonal.
When the minimum ignition temperature of the nano powder needs to be tested, the working steps of adopting the nano dust cloud minimum ignition temperature dispersing device are as follows:
1) a pretest process, namely placing the electrostatic sensitive probes 24-27 in the quartz glass tube 21, placing the nano powder 19 in the powder storage chamber 20, turning off the high-voltage power supply 14, controlling the compressed air control unit to generate airflow with certain pressure without generating temperature by the heating wire 22, blowing up the nano powder 19 in the powder storage chamber 20, forming dust cloud in the quartz glass tube 21 by the nano powder 19, measuring output signals of the electrostatic sensitive probes 24-27 by the measuring and control unit, and calculating the change relation of vector electric field distribution in the quartz glass tube 21 along with time;
2) and (3) repeating the pretesting process in the step 1), solving the change relation of the average value of the measured vector electric field along with time, and moving the electrostatic sensitive probes 24-27 out of the quartz glass tube 21. The variation of the vector electric field distribution in the quartz glass tube 21 with time due to the amount of electric charge generated by friction in the powder dispersion process, i.e., the variation of the amount of electric charge generated by friction in the powder dispersion process with time;
3) and (2) a normal testing process, namely placing the nano powder 19 in a powder storage chamber 23, heating the inside of the quartz glass tube to a specified temperature by a heating wire 22, opening the ion flow generating unit, controlling the flow of the ion flow by using a high-voltage power supply 14, controlling the compressed air control unit to generate airflow with certain pressure and containing positive and negative ions, blowing up the nano powder 19 in the powder storage chamber 23, forming dust cloud in the quartz glass tube 21 by the nano powder 19, and neutralizing the electric charge generated by friction in the powder dispersion process by the positive and negative ions so as to avoid the agglomeration phenomenon of the nano powder 19 in the dispersion process.
In conclusion, the method and the device for dispersing the nano powder based on the ion flow control can well neutralize the charge quantity generated by friction in the dispersing process of the nano powder and prevent nano powder particles from forming aggregates, thereby achieving a uniform dispersing effect and realizing accurate measurement of the combustion and explosion characteristic parameters of the nano-scale dust, such as the minimum ignition energy, the minimum ignition temperature and the like.
The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (7)
1. A nanoscale dust cloud minimum ignition energy dispersal device, comprising:
the electrostatic sensing probe adopts an induction type electrostatic sensing probe, a rotary type electrostatic sensing probe or a vibration capacitance type electrostatic sensing probe and is used for measuring the distribution of a vector electric field in the Hartmann tube;
the measuring and controlling unit is used for converting the charge signal measured by the electrostatic sensitive probe into a voltage signal, calculating the electric field vector distribution in the Hartmann tube according to the voltage signal, and controlling the polarity, the flow and the duration of the ion flow output by the ion flow generating unit according to the electric field vector distribution;
the compressed air control unit provides compressed air with certain pressure and realizes automatic control of the air inflow of the compressed air;
the ion current generating unit provides ion current with certain polarity, flow and duration;
hartmann tubes, provide a space for dust dispersion and testing.
2. The nano-scale dust cloud minimum ignition energy dispersing apparatus of claim 1, wherein: the electrostatic sensitive probes are arranged in four pairs, each pair of probes is a pair, each pair of probes is positioned on the same horizontal shaft and fixed on two sides of the Hartmann tube wall, the two pairs of probes are positioned at different heights, and the central axes where the two pairs of probes are positioned are orthogonal.
3. The nano-scale dust cloud minimum ignition energy dispersing apparatus of claim 1, wherein: the ion current generating unit comprises:
the high-voltage power supply provides a direct-current output voltage within the range of minus 10kV to plus 10kV, and the polarity, the amplitude and the discharge duration of the direct-current output voltage are controlled by the measurement and control unit;
the high-voltage capacitor is used for providing energy storage for the high-voltage power supply;
the electrode needle is arranged in an air pipe connected from the output end of the compressed air control unit to the air inlet of the Hartmann pipe;
the output of the high-voltage power supply is connected to the high-voltage electrode, the ground of the high-voltage power supply is connected to the ground electrode, and the high-voltage electrode and the ground electrode are coaxial and are spaced at a certain distance.
4. A nanoscale dust cloud minimum ignition temperature dispersing device comprises:
the electrostatic sensing probe adopts an induction type electrostatic sensing probe, a rotary type electrostatic sensing probe or a vibration capacitance type electrostatic sensing probe and is used for measuring the distribution of the vector electric field in the Gaoergt-Gernval furnace;
the measuring and controlling unit is used for converting the charge signal measured by the electrostatic sensitive probe into a voltage signal, calculating the electric field vector distribution in the Burger-Gerward furnace according to the voltage signal, and controlling the polarity, flow and duration of the ion flow output by the ion flow generating unit according to the electric field vector distribution;
the compressed air control unit provides compressed air with certain pressure and realizes automatic control of the air inflow of the compressed air;
the powder storage chamber is used for containing nano powder;
the ion current generating unit provides ion current with certain polarity, flow and duration;
a high-grade berger-grimward furnace, which provides dust dispersion and test space.
5. The nanoscale dust cloud minimum ignition temperature dispersing apparatus according to claim 4, wherein: the electrostatic sensitive probes are arranged in four pairs, each pair of probes is positioned on the same horizontal axis and close to the inner side of the wall of the Boerger-Gerovair furnace, the two pairs of probes are positioned at different heights, and the central axes of the two pairs of probes are orthogonal.
6. The nanoscale dust cloud minimum ignition temperature dispersing apparatus according to claim 4, wherein: the ion current generating unit comprises:
the high-voltage power supply provides a direct-current output voltage within the range of minus 10kV to plus 10kV, and the polarity, the amplitude and the discharge duration of the direct-current output voltage are controlled by the measurement and control unit;
the high-voltage capacitor is used for providing energy storage for the high-voltage power supply;
the electrode needle is arranged in a glass tube connected with the output end of the powder storage chamber and the air inlet of the high-gain Burger-Geroval furnace;
the output of the high-voltage power supply is connected to the high-voltage electrode, the ground of the high-voltage power supply is connected to the ground electrode, and the high-voltage electrode and the ground electrode are coaxial and are spaced at a certain distance.
7. A nano powder dispersing method based on ion current control is applied to the dispersing device of any one of claims 1 to 6, and is characterized in that:
measuring the electric field vector distribution in the test space, and calculating the change relation of the vector electric field distribution along with time;
and controlling the polarity, flow and duration of the ion current output by the ion current generating unit according to the relationship to neutralize the quantity of generated positive and negative ions and the quantity of electric charges generated in the dispersion process of the nano powder, so as to prevent the nano powder from agglomerating in the dispersion process and realize the uniform dispersion of the nano-scale dust.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011416511.3A CN112461884A (en) | 2020-12-07 | 2020-12-07 | Nano powder dispersing method and device based on ion flow control |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011416511.3A CN112461884A (en) | 2020-12-07 | 2020-12-07 | Nano powder dispersing method and device based on ion flow control |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112461884A true CN112461884A (en) | 2021-03-09 |
Family
ID=74801184
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011416511.3A Pending CN112461884A (en) | 2020-12-07 | 2020-12-07 | Nano powder dispersing method and device based on ion flow control |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112461884A (en) |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2219782Y (en) * | 1994-10-11 | 1996-02-14 | 西南交通大学 | Ion flow generator |
| CN2268578Y (en) * | 1996-07-18 | 1997-11-26 | 中国兵器工业第二○二研究所 | High voltage electrostatic dust collector |
| JP2006302793A (en) * | 2005-04-25 | 2006-11-02 | Matsushita Electric Works Ltd | Destaticizing method |
| CN101244938A (en) * | 2008-03-13 | 2008-08-20 | 大连理工大学 | Method for controlling minuteness particle accumulation shape |
| JP2010203987A (en) * | 2009-03-05 | 2010-09-16 | Sumitomo Chemical Co Ltd | Method of determining ignition delay time in measurement of minimum ignition energy of dust |
| CN105451424A (en) * | 2015-12-30 | 2016-03-30 | 上海安平静电科技有限公司 | Ion fan or ion bar with electrostatic detection and feedback functions |
| CN107225098A (en) * | 2017-06-28 | 2017-10-03 | 深圳市哈德胜精密科技股份有限公司 | The method for sieving and screening plant of a kind of nano material |
| CN107306471A (en) * | 2015-12-25 | 2017-10-31 | 北京东方计量测试研究所 | A kind of safety-type powder electrostatic arrester |
| CN107782480A (en) * | 2017-11-17 | 2018-03-09 | 北京石油化工学院 | A kind of method of testing and device of the hybrid thing minimum ignition energy amount of combustible dust/fuel gas |
| CN207435028U (en) * | 2017-09-08 | 2018-06-01 | 浙江大学 | The preparation system of the plasma-activated quick-fried synthesis nitridation aluminum nanopowder of nitrogen source zygomite |
| CN109569884A (en) * | 2018-11-16 | 2019-04-05 | 常州大学 | A kind of alternating electric field coagulation and fine dust explosion suppression device and method |
| CN110386374A (en) * | 2018-04-19 | 2019-10-29 | 中国石油化工股份有限公司 | For monitoring and controlling the method and system of polyolefin bunker powder electrostatic |
| CN210071723U (en) * | 2019-04-14 | 2020-02-14 | 宁波工程学院 | Experimental device for survey dust cloud burning explosion characteristic |
-
2020
- 2020-12-07 CN CN202011416511.3A patent/CN112461884A/en active Pending
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2219782Y (en) * | 1994-10-11 | 1996-02-14 | 西南交通大学 | Ion flow generator |
| CN2268578Y (en) * | 1996-07-18 | 1997-11-26 | 中国兵器工业第二○二研究所 | High voltage electrostatic dust collector |
| JP2006302793A (en) * | 2005-04-25 | 2006-11-02 | Matsushita Electric Works Ltd | Destaticizing method |
| CN101244938A (en) * | 2008-03-13 | 2008-08-20 | 大连理工大学 | Method for controlling minuteness particle accumulation shape |
| JP2010203987A (en) * | 2009-03-05 | 2010-09-16 | Sumitomo Chemical Co Ltd | Method of determining ignition delay time in measurement of minimum ignition energy of dust |
| CN107306471A (en) * | 2015-12-25 | 2017-10-31 | 北京东方计量测试研究所 | A kind of safety-type powder electrostatic arrester |
| CN105451424A (en) * | 2015-12-30 | 2016-03-30 | 上海安平静电科技有限公司 | Ion fan or ion bar with electrostatic detection and feedback functions |
| CN107225098A (en) * | 2017-06-28 | 2017-10-03 | 深圳市哈德胜精密科技股份有限公司 | The method for sieving and screening plant of a kind of nano material |
| CN207435028U (en) * | 2017-09-08 | 2018-06-01 | 浙江大学 | The preparation system of the plasma-activated quick-fried synthesis nitridation aluminum nanopowder of nitrogen source zygomite |
| CN107782480A (en) * | 2017-11-17 | 2018-03-09 | 北京石油化工学院 | A kind of method of testing and device of the hybrid thing minimum ignition energy amount of combustible dust/fuel gas |
| CN110386374A (en) * | 2018-04-19 | 2019-10-29 | 中国石油化工股份有限公司 | For monitoring and controlling the method and system of polyolefin bunker powder electrostatic |
| CN109569884A (en) * | 2018-11-16 | 2019-04-05 | 常州大学 | A kind of alternating electric field coagulation and fine dust explosion suppression device and method |
| CN210071723U (en) * | 2019-04-14 | 2020-02-14 | 宁波工程学院 | Experimental device for survey dust cloud burning explosion characteristic |
Non-Patent Citations (6)
| Title |
|---|
| 孙可平: "粉体静电学国内外研究动态与进展", 《物理》, no. 06, 24 June 2000 (2000-06-24) * |
| 庞磊等: "粉尘云最低着火温度的粒径尺度效应", 《中国粉体技术》, no. 01, 28 February 2017 (2017-02-28) * |
| 张伟等: "火***粉尘云最小点火能的实验研究", 《科学技术与工程》, no. 16, 8 June 2018 (2018-06-08) * |
| 李亮亮等: "粉体料仓静电燃爆风险与防控措施", 《中国粉体技术》, no. 06, 25 December 2017 (2017-12-25) * |
| 李畅: "微米及纳米钛粉***特性参数的理论与实验研究", 《中国博士学位论文全文数据库 (工程科技Ⅰ辑)》, no. 9, 15 September 2018 (2018-09-15), pages 4 - 9 * |
| 高鑫等: "非平衡式双极性离子风消电技术与应用", 《中国安全生产科学技术》, no. 01, 30 January 2018 (2018-01-30) * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9791360B2 (en) | Method and apparatus for measuring aerosol particles suspended in gas | |
| US9606038B2 (en) | Particle count measurement device | |
| US20160370320A1 (en) | A method for obtaining aerosol particle size distributions | |
| US20090295400A1 (en) | Electrostatic partricle sensor | |
| AU2020431574B2 (en) | Aspirating smoke sensing device, method, and apparatus for fire detection | |
| CN102590447A (en) | Method and equipment for calibrating dust-measuring instrument | |
| US20170115198A1 (en) | Method and apparatus for measuring aerosol particles of exhaust gas | |
| Intra et al. | An electrostatic sensor for the continuous monitoring of particulate air pollution | |
| CN110044962A (en) | A kind of test device and method of continuous flowing combustible dust cloud kindling sensibility | |
| CN109827994A (en) | A kind of experimental provision and method measuring dust cloud combustion explosion characteristic | |
| CN112461884A (en) | Nano powder dispersing method and device based on ion flow control | |
| Vomela et al. | The charging and mobility of chain aggregate smoke particles | |
| CN110876221A (en) | Plasma temperature distribution measuring system | |
| JP4888597B2 (en) | Fine particle measuring device | |
| KR20190000470A (en) | Differential mobility analyzer and calibrating system for nano particle measuring device using thereof | |
| CN115877147A (en) | Insulating oil partial discharge characteristic simulation test device | |
| Cheng et al. | Electrical Measurement of Flow Rate of Pulverized Coal Suspension | |
| Taillet | Elimination of static charges in the processing of bulk material | |
| Intra et al. | Brownian diffusion effect on nanometer aerosol classification in electrical mobility spectrometer | |
| Intra et al. | Measurements of ion current from a corona-needle charger using a Faraday cup electrometer | |
| Fissan et al. | Rationale for data evaluation of the size distribution measurements of agglomerates and aggregates in gases with extended SMPS-technology | |
| Li et al. | Evaluation of an electrical aerosol detector (EAD) for the aerosol integral parameter measurement | |
| Thonglek et al. | Use of pulse-energized electrostatic precipitator to remove submicron particulate matter in exhaust gas | |
| Intra et al. | Performance evaluation of an electrometer system for ion and aerosol charge measurements | |
| CN106255303B (en) | System for testing motion rule of plasma in closed cylinder structure |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20210309 |