CN203139972U - Standard mixed gas preparation apparatus - Google Patents

Standard mixed gas preparation apparatus Download PDF

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Publication number
CN203139972U
CN203139972U CN 201320153110 CN201320153110U CN203139972U CN 203139972 U CN203139972 U CN 203139972U CN 201320153110 CN201320153110 CN 201320153110 CN 201320153110 U CN201320153110 U CN 201320153110U CN 203139972 U CN203139972 U CN 203139972U
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CN
China
Prior art keywords
output
gas
gaseous mixture
balance
pressure
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CN 201320153110
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Chinese (zh)
Inventor
白光星
白念祥
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淄博祥龙测控技术有限公司
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Priority to CN 201320153110 priority Critical patent/CN203139972U/en
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Abstract

The utility model relates to a standard mixed gas preparation apparatus. The standard mixed gas preparation apparatus comprises a feed gas supply device, a feed gas flow ratio control device, a balance gas supply device, a balance gas flow ratio control device, a pressure stabilizing device, an output pressure stabilizing device, a mixed gas gating cache device, a mixed gas gating output device, a mixed gas output control device and a computer program control display device. The standard mixed gas preparation apparatus can achieve the continuous production of standard mixed gas in various ingredient proportions; the running of the whole production process of the mixed gas is completely automatically controlled; various proportioning parameters can be set on line through a program by the computer program control display device at any time; the process and the result are displayed on a screen immediately; and high-precision mixed gas mixing and automatic cache storage and output are achieved.

Description

The normal mixture system is equipped with device
Technical field
The utility model relates to a kind of normal mixture system and is equipped with device, is mainly used in calibration, atmosphere environment supervision, health care, the clinical examination of the pick up calibration of coal mine gas checkout equipment, product quality supervision and quality control, instrument and meter, evaluation of analytical method etc.
Background technology
The normal mixture body is to make carrier gas (claiming balance gas or background gas again) with a kind of high-purity gas, and it is formulated to add one or more other high-purity gas (claiming component gas or doping gas again) again.Components contents is selected arbitrarily in can be from 1 * 10-6 to 50% scope in the normal mixture body, the compound method of calibrating gas mainly contains weighing method, branch platen press, volumetric method, osmosis, saturation, electrolysis, exponential dilution method, flow-rate ratio mixing method etc., is divided into static distribution method and dynamic air-distributing method from gas dynamical angle.Static distribution method is that the unstrpped gas of a certain amount of gaseous state or steam attitude is added in the container of known volume, charges into diluent gas again, and mixing makes.The advantage of this distribution method is that equipment is simple, processing ease, but more active because of some aerochemistry character, chemical reaction may take place long-time the contact with chamber wall, is applicable to the preparation of the calibrating gas that activity is relatively poor and consumption is little.The dynamic air-distributing method is to make the unstrpped gas of concentration known continuously enter blender with diluent gas by constant ratio to mix, thereby can continuously prepare and supply with certain density calibrating gas.This method shortcoming is the more static distribution method of used instrument and equipment complexity.
Gravimetric method
This method is used pack into each gas component in the steel cylinder of top load precision balance weighing, according to the mass ratio of each component, calculates the concentration of standard gas in the steel cylinder.The distribution steel cylinder is carried out preliminary treatment, remove rusty stain and dirt, and qualified through the water pressure test, and aqueous vapor is removed in decompression heating in baking oven then after the cooling, wash with diluent gas again.Each component gas that requirement is packed in the steel cylinder does not have effects such as corrosion and absorption to the steel cylinder material.This method is compared with other method on production efficiency and is not the best way.But it is foundation with the mass unit, and is reliable on precision, therefore, is acknowledged as the main method of preparation reference gas, and gravimetric method is adopted in the preparation of the reference gas that each is national substantially.
The pressure ratio method
This method is when mixed gas compounding, and the pressure according to measuring each component carries out distribution by prescribed concentration.Can use bohr copper pipe formula pressure gauge, oil manometer, Mike to be listed as vacuum meter difficult to understand etc. as required respectively.The characteristics of this method are, only need pressure gauge, do not have compressor also can prepare.Yet, be easy to generate the heat of compression during filling, and incomplete mixing, filling is very difficult exactly to prescribed concentration.
The mass flow ratio method
This method is carried out the preparation of calibrating gas with the method that flow rate ratio mixes, so the accurate mensuration of flow is the key that guarantees the gas of preparing, and some flow-measuring methods commonly used are subjected to air pressure and Temperature Influence bigger, influences the precision of calibrating gas easily
The static capacity method
To desire formulation components gas (or liquid) and inject an airtight container (mixing chamber) by injection orifice, import diluent gas simultaneously, measure temperature, the pressure of mist.Calculate the concentration of calibrating gas according to injection rate, container volume, temperature, the pressure gauge of formulation components.At present, national standard is still continued to use the distribution of static capacity method air distributing device.This air distributing method is because the uncertainty of pressure and temperature correction causes repeatability and the accuracy prepared relatively poor.State Standard Matter Research Centre has finished the development of novel static capacity method device for formulating in 2002, this device not only can be prepared the mark that component gas under the normal temperature is gaseous state accurately, easily
Accurate gas, and can accurately prepare the calibrating gas that component gas is in a liquid state under the normal temperature.The gas of this method preparation is compared with the gas of gravimetric method, dynamic method preparation and with the calibrating gas that international comparison is used and is had good uniformity.
Permeation tube method
Osmos tube is a kind of equipment of the gas source of the gas of supplying raw materials, and mainly is made up of small container and the permeable membrane of dress material liquid.Small container is made by the inert material of corrosion-resistant and anti-certain pressure, and permeable membrane is made the cap shape with polytetrafluoroethylplastic plastic, is enclosed within the neck of small container, and its thickness is less than 1mm.Its plastic cap thin-walled portion is permeable face, and gas molecule is under its steam pressure effect, and to external diffusion, the infiltration capacity in the unit interval is called permeability by permeable face.Permeation tube method is a kind of more accurate method for the standard gas of preparation low concentration, every volatile liquid and can be frozen or be compressed into liquid gas can be with this method preparing calibrating gas.This method has been successfully used to the preparation of calibrating gas such as sulfur dioxide, nitrogen dioxide.
The preparation of special nature calibrating gas
The preparation of the calibrating gas that character is active
Some gas property is active especially, very easily reacts with oxygen, water, packing container material and concentration is changed, and these gases all were to prepare on a small quantity with methods such as ampoule bottle, saturated vapour pressures in the past, should not transport for long-distance and long term storage.The eighties in 20th century, America NI ST and some special gas companies such as SCOTT etc. develop the undercoating technology of steel cylinder by experiment.This technology has prevented that effectively active gases and steel cylinder inwall from reacting, make the stability of gas increase, but the stability of gas is only limited to half a year, no longer than 1 year, when compound concentration is low the holding time shorter, and the calibrating gas of this method preparation does not form transmission of quantity value and traces to the source.
The preparation of VOC calibrating gas
VOC (VOCs) is air-polluting important indicator in the research department, prepares this type of calibrating gas in the past and all adopts osmosis or diffusion method, obtains the calibrating gas of variable concentrations by the geometry that changes temperature and anemostat.The U.S. just develops method with the accurate weighing micro liquid of capillary as far back as phase early 1980s.At present, the nearly 39 kinds of VOCs calibrating gas that can be traceable to the NIST value have been arranged.In recent years, China researcher used for reference the technology of NIST, developed the VOCs technology of preparing that is fit to China's existence conditions.Obtained progress with capillary tube method, preparation that the gas cylinder method is used for the VOCs calibrating gas, prepared calibrating gas sample has same stability with external comparing with the value of class standard.
The utility model content
According to above deficiency of the prior art, the technical problems to be solved in the utility model is: a kind of above-mentioned defective that solved is provided, has realized that the normal mixture system of high-precision mist mixing, automatic buffer-stored and output is equipped with device.
Normal mixture system described in the utility model is equipped with device and comprises unstripped gas feeder, raw gas flow ratio control device, balance gas feeder, balance throughput ratio control device, pressure stability device, gaseous mixture gating buffer storage, gaseous mixture gating output device, gaseous mixture output-controlling device and computer program control display unit;
The pressure stability device comprises supply gas pressure stabilising arrangement, equilibrium air pressure power stabilising arrangement and output pressure stabilising arrangement;
The unstripped gas feeder is connected with the inlet end of raw gas flow ratio control device after by the supply gas pressure stabilising arrangement, balance gas feeder links to each other with the inlet end of balance throughput ratio control device by behind the equilibrium air pressure power stabilising arrangement, the outlet side of raw gas flow ratio control device and balance throughput ratio control device is connected with gaseous mixture gating output device with gaseous mixture gating buffer storage after by the output pressure stabilising arrangement respectively, and gaseous mixture gating buffer storage, gaseous mixture gating output device are connected successively with the gaseous mixture output-controlling device;
Computer program control display unit is connected with raw gas flow ratio control device, balance gas feeder, balance throughput ratio control device, gaseous mixture gating buffer storage, gaseous mixture gating output device, gaseous mixture output-controlling device and computer program control display unit respectively.
The utility model also comprises the zero clearing device, and the zero clearing device is connected with raw gas flow ratio control device, balance gas feeder, balance throughput ratio control device, gaseous mixture gating buffer storage, gaseous mixture gating output device, gaseous mixture output-controlling device and computer program control display unit respectively.
The pressure stability device adopts well known device, can realize that stabilizing gas pressure gets final product.
Described unstripped gas feeder comprises raw material gas cylinder, pressure-reducing valve, raw gas pressure sensor and the unstripped gas filter that many groups connect successively.
Described raw gas flow ratio control device comprises many group unstripped gas mass flowmenters.The group number of group number and unstripped gas feeder adapts.
Described balance gas feeder comprises air filter, air pump, check valve, balance gas cylinder, pressure switch, pressure regulator, equilibrium air pressure power sensor and the balance air filter that connects successively.
Described balance throughput ratio control device comprises balance makings amount flowmeter.
Described gaseous mixture gating buffer storage comprises surge tank, mixture pressure sensor and the gaseous mixture gating buffer memory magnetic valve that many groups connect successively.
Described gaseous mixture gating output device comprises a plurality of gaseous mixture gating output magnetic valves.
Described gaseous mixture output-controlling device comprises the first output magnetic valve, pressure maintaining valve, flowmeter and the second output magnetic valve that connects successively, wherein the first output magnetic valve also is connected with the gas outlet, and the second output magnetic valve also is connected with alarm with sensor port respectively.
Described zero clearing device comprises zero clearing magnetic valve and balance gas feeder.
The beneficial effect that the utility model has is: the normal mixture system is equipped with the normal mixture body that device can realize producing continuously various component ratios, and the production process of whole mist has realized control operation fully automatically, control the display unit various preparation parameters of online program setting at any time by computer program, and in screen instant playback process and result, realized that high-precision mist mixes, automatically buffer-stored and output, solved current at mine gas detection equipment sensor, the alarm calibration, product quality supervision control, the calibration of instrument and meter, atmosphere environment supervision, health care, clinical examination, the evaluation of analytical method and other need pressing for of high-quality standard mixture occasion.
Description of drawings
Fig. 1 is theory diagram of the present utility model;
Fig. 2 is structural representation of the present utility model.
Among the figure: 1, raw material gas cylinder; 2, pressure-reducing valve; 3, raw gas pressure sensor; 4, unstripped gas filter; 5, unstripped gas mass flowmenter; 6, air filter; 7, air pump; 8, check valve; 9, balance gas cylinder; 10, pressure switch; 11, pressure regulator; 12, equilibrium air pressure power sensor; 13, balance air filter; 14, balance makings amount flowmeter; 15, surge tank; 16, mixture pressure sensor; 17, gaseous mixture gating buffer memory magnetic valve; 18, gaseous mixture gating output magnetic valve; 19, the first output magnetic valve; 20, pressure maintaining valve; 21, flowmeter; 22, the second output magnetic valve; 23, zero clearing magnetic valve, 24, the supply gas pressure stabilising arrangement; 25, equilibrium air pressure power stabilising arrangement; 26, output pressure stabilising arrangement.
The specific embodiment
Below in conjunction with accompanying drawing embodiment of the present utility model is described further:
Shown in Fig. 1~2, a kind of normal mixture system is equipped with device, it is characterized in that: comprise unstripped gas feeder, raw gas flow ratio control device, balance gas feeder, balance throughput ratio control device, pressure stability device, gaseous mixture gating buffer storage, gaseous mixture gating output device, gaseous mixture output-controlling device and computer program control display unit;
The pressure stability device comprises supply gas pressure stabilising arrangement 24, equilibrium air pressure power stabilising arrangement 25 and output pressure stabilising arrangement 26;
The unstripped gas feeder is connected with the inlet end of raw gas flow ratio control device by supply gas pressure stabilising arrangement 24 backs, balance gas feeder links to each other with the inlet end of balance throughput ratio control device by equilibrium air pressure power stabilising arrangement 25 backs, the outlet side of raw gas flow ratio control device and balance throughput ratio control device is connected gaseous mixture gating buffer storage with gaseous mixture gating buffer storage after by output pressure stabilising arrangement 26 respectively with gaseous mixture gating output device, gaseous mixture gating output device is connected successively with the gaseous mixture output-controlling device;
Computer program control display unit is connected with raw gas flow ratio control device, balance gas feeder, balance throughput ratio control device, gaseous mixture gating buffer storage, gaseous mixture gating output device, gaseous mixture output-controlling device and computer program control display unit respectively.
The zero clearing device is connected with raw gas flow ratio control device, balance gas feeder, balance throughput ratio control device, gaseous mixture gating buffer storage, gaseous mixture gating output device, gaseous mixture output-controlling device and computer program control display unit respectively.
The unstripped gas feeder comprises raw material gas cylinder 1, pressure-reducing valve 2, raw gas pressure sensor 3 and the unstripped gas filter 4 that many groups connect successively.
Raw gas flow ratio control device comprises many group unstripped gas mass flowmenters 5.
Balance gas feeder comprises air filter 6, air pump 7, check valve 8, balance gas cylinder 9, pressure switch 10, pressure regulator 11, equilibrium air pressure power sensor 12 and the balance air filter 13 that connects successively.
Balance throughput ratio control device comprises balance makings amount flowmeter 14.
Gaseous mixture gating buffer storage comprises 6 groups of surge tanks that connect successively 15, mixture pressure sensor 16 and gaseous mixture gating buffer memory magnetic valve 17.
Gaseous mixture gating output device comprises 5 gaseous mixture gating output magnetic valves 18.
The gaseous mixture output-controlling device comprises the first output magnetic valve 19, pressure maintaining valve 20, flowmeter 21 and the second output magnetic valve 22 that connects successively, wherein the first output magnetic valve 19 also is connected with the gas outlet, and the second output magnetic valve 22 also is connected with alarm with sensor port respectively.
The zero clearing device comprises zero clearing magnetic valve 23 and balance gas feeder.
Operation principle is:
Under the control of the computer program of computer program control display unit, the surge tank 15 interior gases that program detects gaseous mixture gating buffer storage are lower than when setting value, the unstripped gas feeder begins to raw gas flow ratio control device air feed, and balance gas feeder also begins to balance throughput ratio control device air feed simultaneously.Two kinds of flow ratio control device are exported satisfactory gas separately according to the proportional numerical value of program setting, through gating, flow to corresponding cache jar 15 and store after the mixing.After 15 gases in the buffer tank reached the setting requirement, said apparatus obtained instruction and quits work.Then program detects in turn to other buffer tanks 15 successively, successively according to said process work, finishes the gas configuration storing process of each buffer tank 15.
When needs during to detection load equipment air feed, gaseous mixture gating output device, zero clearing device obtain instruction, begin the clear operation of need verification load device, and gaseous mixture gating output device is according to programmed instruction then, open corresponding buffer tank 15, the mist that output requires.

Claims (10)

1. a normal mixture system is equipped with device, it is characterized in that: comprise unstripped gas feeder, raw gas flow ratio control device, balance gas feeder, balance throughput ratio control device, pressure stability device, gaseous mixture gating buffer storage, gaseous mixture gating output device, gaseous mixture output-controlling device and computer program control display unit;
The pressure stability device comprises supply gas pressure stabilising arrangement (24), equilibrium air pressure power stabilising arrangement (25) and output pressure stabilising arrangement (26);
The unstripped gas feeder is connected with the inlet end of raw gas flow ratio control device by supply gas pressure stabilising arrangement (24) back, balance gas feeder links to each other with the inlet end of balance throughput ratio control device by equilibrium air pressure power stabilising arrangement (25) back, the outlet side of raw gas flow ratio control device and balance throughput ratio control device is connected gaseous mixture gating buffer storage with gaseous mixture gating buffer storage after by output pressure stabilising arrangement (26) respectively with gaseous mixture gating output device, gaseous mixture gating output device is connected successively with the gaseous mixture output-controlling device;
Computer program control display unit is connected with raw gas flow ratio control device, balance gas feeder, balance throughput ratio control device, gaseous mixture gating buffer storage, gaseous mixture gating output device, gaseous mixture output-controlling device and computer program control display unit respectively.
2. normal mixture system according to claim 1 is equipped with device, it is characterized in that: also comprise the zero clearing device, the zero clearing device is connected with raw gas flow ratio control device, balance gas feeder, balance throughput ratio control device, gaseous mixture gating buffer storage, gaseous mixture gating output device, gaseous mixture output-controlling device and computer program control display unit respectively.
3. normal mixture system according to claim 1 is equipped with device, it is characterized in that: described unstripped gas feeder comprises raw material gas cylinder (1), pressure-reducing valve (2), raw gas pressure sensor (3) and the unstripped gas filter (4) that many groups connect successively.
4. normal mixture system according to claim 1 is equipped with device, it is characterized in that: described raw gas flow ratio control device comprises many group unstripped gas mass flowmenters (5).
5. normal mixture system according to claim 1 is equipped with device, it is characterized in that: described balance gas feeder comprises air filter (6), air pump (7), check valve (8), balance gas cylinder (9), pressure switch (10), pressure regulator (11), equilibrium air pressure power sensor (12) and the balance air filter (13) that connects successively.
6. normal mixture system according to claim 1 is equipped with device, it is characterized in that: described balance throughput ratio control device comprises balance makings amount flowmeter (14).
7. normal mixture system according to claim 1 is equipped with device, it is characterized in that: described gaseous mixture gating buffer storage comprises surge tank (15), mixture pressure sensor (16) and the gaseous mixture gating buffer memory magnetic valve (17) that many groups connect successively.
8. normal mixture system according to claim 1 is equipped with device, it is characterized in that: described gaseous mixture gating output device comprises a plurality of gaseous mixture gating output magnetic valves (18).
9. normal mixture system according to claim 1 is equipped with device, it is characterized in that: described gaseous mixture output-controlling device comprises the first output magnetic valve (19), pressure maintaining valve (20), flowmeter (21) and the second output magnetic valve (22) that connects successively, wherein the first output magnetic valve (19) also is connected with the gas outlet, and the second output magnetic valve (22) also is connected with alarm with sensor port respectively.
10. normal mixture system according to claim 1 and 2 is equipped with device, it is characterized in that: described zero clearing device comprises zero clearing magnetic valve (23) and balance gas feeder.
CN 201320153110 2013-03-29 2013-03-29 Standard mixed gas preparation apparatus CN203139972U (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103143293A (en) * 2013-03-29 2013-06-12 淄博祥龙测控技术有限公司 Standard mixed gas preparation device
CN105223319A (en) * 2015-10-22 2016-01-06 济宁市计量测试所 Detection system and method thereof are demarcated by a kind of Mobile Online based on calibrating and measuring car
CN105301191A (en) * 2015-10-22 2016-02-03 济宁市计量测试所 Correction and calibration vehicle and method
CN105334299A (en) * 2015-12-15 2016-02-17 北京雪迪龙科技股份有限公司 Standard gas generation system and method for dynamically monitoring standard gas
CN105822897A (en) * 2016-05-13 2016-08-03 国家电网公司 Method and device for dynamic gas mixing and filling under pressure within wide range
CN106237877A (en) * 2016-09-28 2016-12-21 北京明尼特环保设备有限公司 A kind of dynamically gas-liquid mixed distributing instrument

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103143293A (en) * 2013-03-29 2013-06-12 淄博祥龙测控技术有限公司 Standard mixed gas preparation device
CN105223319A (en) * 2015-10-22 2016-01-06 济宁市计量测试所 Detection system and method thereof are demarcated by a kind of Mobile Online based on calibrating and measuring car
CN105301191A (en) * 2015-10-22 2016-02-03 济宁市计量测试所 Correction and calibration vehicle and method
CN105301191B (en) * 2015-10-22 2017-07-14 济宁市计量测试所 One kind calibration calibration vehicle and its calibration scaling method
CN105223319B (en) * 2015-10-22 2017-09-08 济宁市计量测试所 A kind of Mobile Online's demarcation detecting system and its method based on calibrating and measuring car
CN105334299A (en) * 2015-12-15 2016-02-17 北京雪迪龙科技股份有限公司 Standard gas generation system and method for dynamically monitoring standard gas
CN105822897A (en) * 2016-05-13 2016-08-03 国家电网公司 Method and device for dynamic gas mixing and filling under pressure within wide range
CN106237877A (en) * 2016-09-28 2016-12-21 北京明尼特环保设备有限公司 A kind of dynamically gas-liquid mixed distributing instrument
CN106237877B (en) * 2016-09-28 2019-05-17 北京明尼特环保设备有限公司 A kind of dynamic gas-liquid mixed distributing instrument

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