CN211602658U - Composite fiber type mercury capturing device - Google Patents

Abstract

The utility model relates to a mercury device is caught to composite fiber formula, catch mercury composite fiber and be parallel with the quartz capsule including the quartz capsule and locate the mercury composite fiber of catching in the quartz capsule, catch many capillaries of mercury composite fiber including gathering the beam forming, the capillary is the silica capillary, and the internal surface and the surface of capillary have all covered gold coating. The periphery winding of quartz capsule has the heating wire, and the both ends and the heating control circuit of heating wire link to each other, and the both ends of quartz capsule are air inlet and gas outlet respectively, and air inlet and gas outlet department all are equipped with the cassette. The utility model discloses a catch mercury composite fiber, the surface area is far greater than gilt quartz sand for mercury element's enrichment rate is greater than 95%, the utility model discloses have high entrapment rate and release rate, and the live time is longer, and stability is better, and the preliminary treatment of the extremely low mercury concentration of mainly used provides pure mercury gas for various gas mercury analysers.

Description

Composite fiber type mercury capturing device

Technical Field

The utility model relates to a gaseous state mercury analyzer's enrichment device in advance especially relates to a mercury device is caught to composite fiber formula.

Background

Mercury is a highly toxic substance, more than 90% of mercury exists mainly in the form of gaseous elemental mercury in the atmosphere, has the characteristics of high chemical inertness and low water solubility, has long existence time, can migrate for tens of thousands of kilometers along with the atmospheric circulation, and is a globally recognized heavy metal pollutant. Meanwhile, mercury in the earth crust is a companion of the mineral deposit, and is easy to move to the surface of the earth crust along with the earth crust movement through the strong penetrating power of the mercury, so that the mercury is also a remarkable index for distinguishing the earth crust movement and the geological mineral deposit.

Mercury concentration measurement is a direct means of mercury pollution and crust analysis, and currently, gaseous mercury is generally analyzed by pre-enriching the gaseous mercury and then thermally analyzing the gaseous mercury and inputting the gaseous mercury into an atomic absorption analyzer or other types of gaseous mercury analyzers for concentration analysis. In practical application, the mercury concentrator is gradually converted into a mercury trap tube from initial activated carbon, elemental mercury is captured by utilizing the adsorption principle that gold and mercury interact to form Au2Hg alloy (amalgam) at normal temperature, pure mercury gas is released by instantaneous high-temperature heating, and the detection sensitivity can be improved and the interference of gas on the detection accuracy can be reduced by the enrichment-pyrolysis of the mercury trap tube. The mercury trap is generally made of gold wire or gold sand and the combination of the gold wire and the gold sand, the mercury trap has high enrichment rate and release rate, but the use frequency can only be maintained for 400-500 times, the manufacturing cost is high, the gold wire or the gold sand is greatly influenced by gas production flow in the long-term use process, the trapping rate of the gold wire or the gold sand is reduced along with the increase of the use time, the performance of the mercury trap is reduced, and the accuracy of a mercury analyzer is influenced.

Disclosure of Invention

The utility model discloses a solve above-mentioned technical problem, provide a mercury device is caught to composite fiber formula, it has high entrapment rate and release rate, and the live time is longer, and stability is better, and the preliminary treatment of the extremely low mercury concentration of mainly used provides pure mercury gas for various gas mercury analysers.

The above technical problem of the present invention can be solved by the following technical solutions: the utility model discloses a mercury composite fiber is caught in quartz capsule and locating the quartz capsule, catches mercury composite fiber and is parallel with the quartz capsule, and the periphery winding of quartz capsule has the heating wire, and the both ends and the heating control circuit of heating wire link to each other, and the both ends of quartz capsule are air inlet and gas outlet respectively. The mercury capturing composite fiber is the core of the mercury capturing device and is used for capturing gaseous mercury in a gas sample. The gas inlet of quartz capsule is used for gathering gaseous sample, and the gas outlet of quartz capsule links to each other with gas mercury analyzer. And a gas sample flows into the quartz tube from the gas inlet of the quartz tube and enters the mercury-trapping composite fiber, mercury gas in the gas is adsorbed on the surface of the mercury-trapping composite fiber to form gold amalgam, and the rest gas is discharged from the gas outlet of the quartz tube. And then the heating control circuit is started to work, stable voltage is output to the electric heating wire, under the heating of the electric heating wire, the gold amalgam on the surface of the mercury-trapping composite fiber is pyrolyzed to form pure mercury gas, and the pure mercury gas flows out of the gas outlet of the quartz tube and flows into a gas-mercury analyzer for analyzing the concentration of the mercury gas in the gas.

Preferably, the mercury capturing composite fiber comprises a plurality of capillaries gathered into a bundle, the capillaries are silica capillaries, and the inner surfaces and the outer surfaces of the capillaries are both covered with gold coatings. The capillary tube bundling structure is adopted, the surface area of the capillary tube bundling structure is far larger than that of gold-plated quartz sand, so that the enrichment rate is larger than 95%, and in the long-term use process, the resistance is not changed, and therefore the mercury capturing efficiency is not reduced along with the increase of time. The gold coating is prepared by a solution dipping method, has thin thickness, good firmness with the wall of the capillary tube, difficult shedding and good heat release, is beneficial to adsorbing and releasing mercury gas, and greatly improves the adsorption rate and the release rate of the mercury trap.

Preferably, the length of the capillary is 3-3.5 cm, the outer diameter is 2.8-3 mm, the inner diameter is 1-1.2 mm, and the thickness of the gold coating is 200-300 nm.

Preferably, the heating wire is spirally wound outside the quartz tube, and the spirally wound heating wire covers the mercury-capturing composite fiber. The heat energy utilization rate is improved, and the better heat release performance of the mercury capturing composite fiber is ensured. The heating wire is preferably a nickel-chromium wire, so that the oxidation resistance is good, the diameter change is less than 10% after long-term heating and cooling, and the pyrolysis temperature is stable.

Preferably, the air inlet and the air outlet of the quartz tube are both provided with filter sheets, the length of the mercury capturing composite fiber is smaller than that of the quartz tube, and the two filter sheets are respectively blocked between two ends of the quartz tube and two ends of the mercury capturing composite fiber. The filter disc is spherical and made of quartz cotton. The filter disc is used for filtering dust and water vapor in the gas to be detected and preventing the mercury-capturing composite fiber from being blocked. The quartz cotton ball is adopted, and due to the flexibility of the quartz cotton ball, the filter disc is tightly attached to the inner wall of the quartz tube, so that two ends of the mercury capturing composite fiber are completely blocked, and a good filtering effect is achieved.

Preferably, the quartz tube has a wall thickness of 1mm, a length of 10cm and an outer diameter of 20-25 mm.

Preferably, the heating control circuit comprises a voltage conversion module, a constant voltage module and a timing module;

the voltage conversion module is used for converting the input voltage into 14V voltage and supplying the 14V voltage to the constant voltage module and the timing module;

the constant voltage module is used for controlling the input voltage of the heating wire to be stabilized between 13.8V and 14.2V, so that the temperature of the heating wire can reach 750-800 ℃;

the timing module is used for controlling the electrifying time of the electric heating wire to be 35S, so that the gold amalgam on the mercury capturing composite fiber is thoroughly pyrolyzed and released.

The heating control circuit controls the on-off and the electrified voltage of the electric heating wire, thereby controlling the heating temperature and the heating time.

The utility model has the advantages that: the surface area of the used mercury capturing composite fiber is far larger than that of gold-plated quartz sand, so that the enrichment rate is larger than 95%, and in the long-term use process, the resistance is not changed, and therefore the mercury capturing efficiency is not reduced along with the increase of time; the gold coating is thin, the firmness between the substrate and the gold film is good, the gold coating is not easy to fall off, and the heat release performance is good; the heating wire adopts nickel-chromium wire, uses the heating temperature of constant voltage circuit control heating wire, and the temperature is stable, and oxidation resistance is good, heats-cools off for a long time, and its diameter changes and is less than 10%, makes the pyrolysis temperature comparatively stable, and the release rate is stable, and the life-span of catching the mercury device is longer, can use more than 1500 times. The utility model discloses enrichment-heat release performance is good, and the life-span is longer, and consumes gold volume low, and the cost of manufacture is low, can regard as the gaseous preprocessing device of multiple gas mercury analyzer.

Drawings

Fig. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a schematic end view of the mercury capturing composite fiber of the present invention installed in a quartz tube.

In the figure, 1, a quartz tube, 2, mercury-capturing composite fibers, 3, a filter disc, 4, an electric heating wire, 5, a heating control circuit and 6, a capillary tube are arranged.

Detailed Description

The technical solution of the present invention is further specifically described below by way of examples and with reference to the accompanying drawings.

Example (b): a composite fiber type mercury trap of this embodiment, as shown in fig. 1, includes a quartz tube 1, a mercury trap composite fiber 2, a filter 3, and a heating wire 4. The two ends of the quartz tube are respectively provided with an air inlet and an air outlet, the mercury capturing composite fiber is positioned in the quartz tube, the periphery of the mercury capturing composite fiber is basically clung to the inner wall of the quartz tube, the mercury capturing composite fiber is parallel to the quartz tube, the length of the mercury capturing composite fiber is smaller than that of the quartz tube, gaps are formed between the two ends of the mercury capturing composite fiber and the two ends of the quartz tube, filter sheets are respectively arranged in the two gaps, each filter sheet is a quartz cotton ball and plugs the air inlet and the air outlet of the quartz tube, and due to the flexibility of the quartz cotton balls, the two ends of the mercury capturing composite fiber can be completely blocked by the filter sheets, so that a good filtering effect is. The heating wire is spirally wound on the periphery of the quartz tube, the heating wire is made of nickel-chromium alloy, the resistance is 5.0-5.3 omega, the spirally wound heating wire covers the whole mercury-trapping composite fiber, two ends of the heating wire are connected with the heating control circuit 5, and the heating control circuit controls the on-off and the power-on voltage of the heating wire so as to control the heating temperature and the heating time. The heating control circuit comprises a voltage conversion module, a constant voltage module and a timing module. The voltage conversion module is used for converting the input voltage into 14V voltage and supplying the 14V voltage to the constant voltage module and the timing module; the constant voltage module is used for controlling the input voltage of the heating wire to be stabilized between 13.8V and 14.2V, so that the temperature of the heating wire can reach 750-800 ℃; the timing module is used for controlling the electrifying time of the electric heating wire to be 35S, so that the gold amalgam on the mercury capturing composite fiber is thoroughly pyrolyzed and released. As shown in fig. 2, the mercury capturing composite fiber includes a plurality of capillaries 6 gathered in a bundle, the capillaries being silica capillaries, and the inner and outer surfaces of the capillaries being covered with a gold coating. In this example, the quartz tube had a wall thickness of 1mm, a length of 10cm and an outer diameter of 25 mm. The capillary has a length of 3cm, an outer diameter of 3mm, an inner diameter of 1.2mm, and a gold coating thickness of 250 nm.

The working process of the composite fiber type mercury capturing device is as follows: in order to prevent the quartz tube from being heated by the electric heating wire to be cracked at high temperature, the quartz tube needs to be annealed and heat-treated in a high-temperature furnace at 300 ℃ for 3 hours before being used, is cooled, is ultrasonically cleaned for 30 minutes by absolute ethyl alcohol and is dried for later use. The gas inlet of quartz capsule is used for gathering gaseous sample, and the gas outlet of quartz capsule links to each other with gas mercury analyzer. A gas sample flows into the quartz tube from a gas inlet of the quartz tube, dust particles and water vapor in the gas are removed through the filter disc, the gas enters the mercury capturing composite fiber, mercury gas in the gas is adsorbed on the gold coating of the mercury capturing composite fiber to form gold amalgam, and the rest gas is discharged from a gas outlet of the quartz tube; and then starting a heating control circuit to work, outputting stable voltage to the electric heating wire, rapidly heating the electric heating wire to 750-800 ℃, so that the gold amalgam on the surface of the mercury-trapping composite fiber is pyrolyzed to form pure mercury gas, the pure mercury gas flows out of the gas outlet of the quartz tube and flows into a gas-mercury analyzer, and after the electric heating wire is continuously heated for 35 seconds, the electric heating wire is powered off to stop heating, and the electric heating wire is naturally cooled.

The mercury capturing composite fiber adopted by the utility model has the surface area far larger than gold-plated quartz sand, so that the enrichment rate of mercury elements is larger than 95%, and in the long-term use process, the resistance is not changed, therefore, the mercury capturing efficiency is not reduced along with the increase of time; the gold coating is thin, the firmness between the substrate and the gold film is good, the gold coating is not easy to fall off, and the heat release performance is good; the heating wire adopts nickel-chromium wire, uses the heating temperature of constant voltage circuit control heating wire, and the temperature is stable, and oxidation resistance is good, heats-cools off for a long time, and its diameter changes and is less than 10%, makes the pyrolysis temperature comparatively stable, and the release rate is stable, and the life-span of catching the mercury device is longer, can use more than 1500 times. The utility model discloses enrichment-heat release performance is good, and the life-span is longer, and consumes gold volume low, and the cost of manufacture is low, can regard as the gaseous preprocessing device of multiple gas mercury analyzer.

Claims (6)

1. The utility model provides a mercury device is caught to composite fiber formula which characterized in that includes the quartz capsule and locates the mercury complex fiber of catching in the quartz capsule, catches mercury complex fiber and is parallel with the quartz capsule, and the periphery winding of quartz capsule has the heating wire, and the both ends of heating wire and heating control circuit link to each other, and the both ends of quartz capsule are air inlet and gas outlet respectively.

2. The composite fiber type mercury capture device according to claim 1, wherein the mercury capture composite fibers comprise a plurality of capillaries gathered into a bundle, the capillaries are silica capillaries, and the inner and outer surfaces of the capillaries are covered with a gold coating.

3. The composite fiber type mercury trap device according to claim 2, wherein the length of the capillary tube is 3-3.5 cm, the outer diameter is 2.8-3 mm, the inner diameter is 1-1.2 mm, and the thickness of the gold coating is 200-300 nm.

4. The composite fiber type mercury trap device according to claim 1, wherein the gas inlet and the gas outlet of the quartz tube are provided with filter sheets, the length of the mercury trap composite fiber is smaller than that of the quartz tube, and the two filter sheets are respectively blocked between two ends of the quartz tube and two ends of the mercury trap composite fiber.

5. The composite fiber type mercury trap device according to claim 3, wherein the quartz tube has a wall thickness of 1mm, a length of 10cm and an outer diameter of 20-25 mm.

6. The composite fiber type mercury capturing device according to claim 1, 2 or 4, wherein the heating control circuit comprises a voltage conversion module, a constant voltage module and a timing module;

the voltage conversion module is used for converting the input voltage into 14V voltage and supplying the 14V voltage to the constant voltage module and the timing module;

the constant voltage module is used for controlling the input voltage of the heating wire to be stabilized between 13.8V and 14.2V, so that the temperature of the heating wire can reach 750-800 ℃;

the timing module is used for controlling the electrifying time of the electric heating wire to be 35S, so that the gold amalgam on the mercury capturing composite fiber is thoroughly pyrolyzed and released.

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