CN100339149C - Co2 pressured purifying liquefying method and device and use in area refrigeration - Google Patents

Abstract

The present invention relates to a refrigeration technique, particularly to a method and a device for CO2 pressurized purification and liquefaction, the application of the method and the device in area refrigeration. According to the method for CO2 pressurized purification and liquefaction, gaseous phase CO2 is purified under the condition of not less than 4.0MPa of pressure, so organic matters, dust and water are removed, and the CO2 is liquified by pressurization under the condition of ice-water. The device of the present invention has the advantages of low cost, no impurity or room temperature influence and wide application range, and the method is simple, economic, convenient and practical. The device is used as an area refrigeration source of fuel two-dimensional gas chromatography, and good experimental results can be obtained.

Description

CO 2Band is pressed method and device and the application on the refrigeration of zone that purifies liquefaction

Technical field

The present invention relates to Refrigeration Technique, specifically CO ₂Band is pressed method and device and the application on the refrigeration of zone that purifies liquefaction.

Background technology

Refrigeration Technique all is widely used in chemical industry, pharmacy, analysis, processing, usually the cold-producing medium that adopts has (document 1: Bai Jingtian etc., industrial chemicals pandect the third volume of a work, chemical engineering industry publishing houses such as air, water, ice, freon, liquid nitrogen, liquid oxygen, dry ice, Beijing, 1993; 1009-1019).From the angle of deep cooling, mainly contain liquid nitrogen, liquid oxygen, dry ice, freon etc.; Liquid nitrogen, liquid oxygen can be chilled to below-200 ℃, but originate, carry all inconveniences, and equipment investment and expensive raw material price.Because big with the temperature difference of air, in transportation and use, be incubated strictly, loss of refrigeration capacity is big.Freon is owing to the environmental issue application is very restricted.Dry ice is liquid CO ₂The decompression be deformed into mutually, convenient sources, low price, refrigeration can reach below-56 ℃, in use to equipment substantially without what big investment, so dry ice be widely used as refrigeration source, and adopt more the dry ice bath or directly the use.However, the low-temperature receiver of temperature control adopts liquid nitrogen more.

Though dry ice has source of the gas convenient as cold-producing medium, low price does not almost have the advantage of supplemental equipment requirement, the CO of domestic production ₂Extract and reclaim in fermentation gas, lime-kiln gas and the flue gas that unstripped gas from synthetic ammonia or hydrogen gas production process, liquor are produced mostly.The industrial liquid CO that is used for purposes such as chemical industry, welding, refrigeration ₂Adopt the standard of GB 6025-85 (State Bureau of Technical Supervision), contain moisture, mineral oil, reach other impurity; The CO that adopt in the laboratory ₂Mostly be the byproduct that liquor is produced, include a large amount of ethanol, water, compressor oil and dust (document 1: Bai Jingtian etc., industrial chemicals pandect the third volume of a work, chemical engineering industry publishing house, Beijing, 1993; 1009-1019); Concrete index is referring to table 1.These impurity generally can not bring any problem when directly putting dry ice and do cryostat, but when being used for purposes such as chemical industry, welding, refrigeration, bring injurious effects sometimes, during especially controlled use, these impurity bring great trouble to control section: this is owing to when controlled use, liquid CO ₂Be to be transported to make the use instant decompression, be phase-changed into dry ice, discharge a large amount of colds simultaneously; Instant decompression is by valve member or resistance gauge, CO ₂Meetings such as a large amount of ethanol, water, compressor oil and the dust that contain are to valve member and resistance gauge result in blockage (ethanol, water are that quenching is frozen during owing to phase transformation) or change in resistance.

Table 1 liquid CO ₂Product standard

Standard code	GB 6025-85				GB 1917-80	GB 10621-89
							Classification and rank	The I class	II class one-level	II class secondary	Three grades of II classes	Food-grade (fermentation method)	Food-grade (limekiln, ammonia factory by-product)
CO 2, % (volume)	99.8	99.5	99.0	99.0	≥99.0	99.5
							Moisture content % (weight)	0.005	0.05	0.10			0.2
Acidity					Aqueous solution acescency	Aqueous solution acescency
							Oil content					10g dry ice is divided oil stains-less on filter paper	10g dry ice is divided oil stains-less on filter paper

H 2SO，HNO 2，CO，H 2S， PH 3And organic reducing thing						Must not detect
							Smell	No foreign odor				No abnormal stink and assorted flavor	Free from extraneous odour

In addition, from CO ₂Temperature-entropy curve, i.e. Fig. 1 (document 2:Cramer, F., ChemieIngenieut-Technik, 1955; 27 (8/9), 181-197) as can be seen: CO ₂Critical point be 31.04 ℃, pressure is 72.85atm; Three phase point is-56.57 ℃, and pressure is 0.518Mpa.So bottled CO ₂Limited by room temperature as cold-producing medium: when being higher than 31.04 ℃, all exist with gas form, along with the reduction of temperature, the liquid CO in the gas cylinder ₂Increase gradually, the pressure of gas cylinder decreases, so liquid CO 2 is subjected to gas cylinder temperature effect as the application of cold-producing medium.At present, gas phase CO ₂After being with and pressing purification, liquefying, control is deformed into dry ice mutually and still is not reported as the technology that low-temperature receiver freezes.

On purifying problem, liquid CO ₂Purifying and transporting process, very high to the variation requirement of pressure and temperature, the variation of pressure and temperature all is easy to cause phase transformation, causes the loss of cold, and sort this problem out is very difficult technically.

Summary of the invention

In order to address the above problem, the object of the present invention is to provide a kind of gas cylinder temperature effect that is subjected to little, the gas phase CO that loss of refrigeration capacity is few ₂Band press to purify the method for liquefaction and as the application of regional refrigeration source.

For achieving the above object, the technical solution used in the present invention is: CO ₂Band is pressed the method that purifies liquefaction, and it is gas phase CO ₂Be not less than (temperature of gas cylinder should not be lower than 5 ℃ simultaneously) purification under the 4.0Mpa condition at pressure, remove organic matter, dust and water, and then be with hydraulic fluidization down in ice-water condition;

For the device of realizing said method the present invention design is: it is by CO ₂The clarifier a of source of the gas, pressure gauge, interior dress activated carbon, the clarifier b of interior dress silica gel, coil pipe and gas resistance gauge are connected in series by pipeline, wherein coil pipe places ice-water-bath, and all stops up the stainless (steel) wire of sintering in the outlet of clarifier a and clarifier b;

The application on the refrigeration of zone of carbon dioxide that the inventive method obtains and device is with liquefaction CO ₂By air resistance device sudden pressure reduction, utilize liquid CO ₂Be phase-changed into dry ice and freeze, and reach controlled purpose.

Wherein said zone refrigeration has obtained effect preferably when using as comprehensive two dimensional gas chromatography zone refrigeration source.

The present invention has following advantage:

1. cost is low.CO ₂Refrigeration Technique all is widely used in chemical industry, pharmacy, analysis, processing, laboratory research, because dry ice comes from liquid CO ₂, convenient sources, low price, refrigeration can reach below-56 ℃, refrigerating speed is fast, operating characteristics well, in use to equipment substantially without what big investment, so dry ice is widely used as refrigeration source.

2. applied range.By liquid CO ₂Control is deformed into dry ice mutually as regional low-temperature receiver, because the influence of impurity and room temperature has limited its application; And the present invention adopts the gas phase high pressure CO ₂Band is pressed and is purified, and the band hydraulic fluidization by the resistance gauge sudden pressure reduction, is utilized highly pressurised liquid CO again under ice-water condition ₂The a large amount of colds that discharge continuously when being phase-changed into dry ice can reach below the 60 negative degree regional temperature; And can change the scope of refrigerated area and the effect of refrigeration by the size of change spout and the size of resistance; And can be by the switch of gas cylinder or the solenoid control refrigeration of gas circuit.

3. both simple economy of the inventive method is convenient again feasible.

4. the present invention is used as the regional refrigeration source of comprehensive two dimensional gas chromatography, can obtain good experimental result.

Description of drawings

Fig. 1 is CO ₂Temperature-entropy curve.

Fig. 2 is apparatus of the present invention structural representation.

Fig. 3 is CO ₂Pressure-enthalpy diagram.

Fig. 4 is the distribution map of spout near zone temperature of the present invention.

Fig. 5 is a comprehensive two dimensional gas chromatography analytical work process schematic diagram.

Fig. 6 is a triphen separate colors spectrogram.

Fig. 7 is a gasoline separate colors spectrogram.

The local expansive color spectrogram 1 that Fig. 8 separates for gasoline.

The local chromatogram 2 that Fig. 9 separates for gasoline.

The specific embodiment

Embodiment

In order to solve the influence to using of impurity and ambient temperature, present embodiment adopts CO ₂Press purification at the gas phase band, ice-water condition is the band hydraulic fluidization down, by the resistance gauge sudden pressure reduction, utilizes liquid CO ₂The a large amount of cold that discharges when being phase-changed into dry ice freezes, and reaches controlled purpose.Concrete structure is seen Fig. 2: wherein pressure gauge 2 ranges are 10Mpa, and dress takes off hydrocarbon agent (for example activated carbon etc., what present embodiment adopted is activated carbon) in the clarifier a 3; The dress dehydrating agent (for example: silica gel, inorganic salts magnesium sulfate etc. in the clarifier b 4, what present embodiment adopted is silica gel), the outlet of each clarifier is stopped up with the sintered stainless steel net, the copper pipe of pipeline and coil pipe 6 usefulness external diameter 3mm, and liquid CO is flattened or used in air resistance device 7 usefulness 1/16 stainless steel tube part ₂Magnetic valve can decide the size of resistance according to the size that cold requires.

Gas CO ₂Remove organic matter and mineral oil through activated carbon, silica gel removes water, and the sintered stainless steel net of clarifier outlet removes dust and broken cleanser; As can be seen from Figure 3: the gas cylinder temperature be 5 ℃ and the band press strip spare under (＞4.0Mpa), by the gaseous state CO of ice-water for cooling (0 ℃) ₂Can become liquid CO with pressure ₂Liquid CO ₂Form dry ice by air resistance device 7 back puffings, the spout near zone at air resistance device 7 discharges a large amount of colds simultaneously, and refrigeration can be controlled by magnetic valve or gas cylinder 1 switch.

Gas CO as can be seen from Figure 3 ₂In purification and course of conveying pressure and temperature there is not strict requirement, at course of conveying mesohigh gaseous state CO ₂Pressure and temperature when certain limit changes, gaseous state CO ₂The loss of energy is little, just can solve CO set forth above by Fig. 2 structure like this ₂Two problems that occur when control is used as cold-producing medium.

The Temperature Distribution of spout near zone refrigeration:

In Fig. 2 structure, adopt spout to make the air resistance device, make sensing element with thermocouple (EU-2) K of external diameter 0.5mm, the XL43 digital display meter thermometric of usefulness Shanghai milky way instrument plant, apart from the Temperature Distribution of spout dead ahead different distance shown in Fig. 4 and table 2.

As can be seen from Table 2 the temperature of spout not only with distance dependent, and with gas CO ₂Pressure relevant.When the gas cylinder temperature is low, CO in the gas cylinder ₂The also low (see figure 3) of pressure, the temperature of respective jets higher (only 3mm place because flow rate effect make an exception), and thermograde is big, vice versa.When adopting ice-water-bath cooling, under the vapor-liquid equilibrium condition, P _CO2=3.5Mpa, when being lower than 5 ℃ as if the gas cylinder temperature, P in the gas cylinder _CO2＜4.0Mpa, spout come out only CO ₂Gas, form and cannot see dry ice.Therefore winter, gas cylinder should be placed on indoorly, was not less than 5 ℃ of (P when guaranteeing vapor-liquid equilibrium _CO2∴ 4.0Mpa).When the gas cylinder temperature is higher than 5 ℃ of uses, when being lower than 4.0Mpa, the pressure of gas cylinder just should change bottle.So just can guarantee normally to use CO throughout the year ₂As refrigeration source.

The different CO of table 2 ₂The distribution of spout near zone temperature under the pressure

P co2=4.5Mpa (the gas cylinder temperature is 10 ℃)		P co2=4.0Mpa (the gas cylinder temperature is 5 ℃)
				From jet opening distance mm	Temperature ℃	From jet opening distance mm	Temperature ℃
3	-60	3	-70
				5	-50	5	-48
10	-46	10	-24
				20	-24	20	-10
30	-13	30	-3

Application examples 1

Obtain and be used for comprehensive two dimensional gas chromatography analysis triphen sample

Comprehensive two dimensional gas chromatography analytical work process is seen Fig. 5, because it has very strong separative efficiency, obtain very big attention in analysis field in recent years, one of its key problem in technology is design (document 3:Jan Beens, the Mohamed Adahchour in continuous cooling source, Rene J., J.Vreuls, Klaas VAN Altena, Udo A.Th.Brinkman, J.Chromatogr.A., 2001; 919,127-132).This example adopts as shown in Figure 2, and apparatus of the present invention provide continuous refrigeration source.

Analytical conditions for gas chromatography:

Chromatograph: the GC-900 of Shanghai Kechuang chromatographic apparatus company

Acquisition processing system: the intelligent information Graduate School of Engineering N-2000 of Zhejiang University binary channels work station

Chromatographic column a 2 DB-51 $10m\≅0.25\mathrm{mm}\≅0.25\mathrm{\μm}$

Chromatographic column b 4 carbowax $0.50m\≅0.10\mathrm{mm}\≅0.10\mathrm{\μm}$

Vaporizer 1:300 ℃; Hydrogen flame detector 5:140 ℃; Hot jet pipe 6:250 ℃

Column temperature: 35 ℃; Split ratio 1: 100; Carrier gas: nitrogen.

Hot jet pipe nitrogen pressure 0.5Mpa uses solenoid control, 6.5 seconds cycles, 200 milliseconds of opening times.

Sample: benzene, toluene, ethylbenzene, dimethylbenzene.

Wherein: 7 is hot jet pipe; 3 is column joint.

The chromatography spectrogram is seen Fig. 6, from chromatographic fractionation figure as can be seen each chromatographic peak all caught by cold, gone out after then being resolved by the hot gas of each cycle 200ms pulse again; The result is that a chromatographic peak is divided into several pulses, and the cycle of each pulse is 6.5 seconds.

Application examples 2

Cold catching is used for comprehensive two dimensional gas chromatography Analysis of Complex sample

Analytical conditions for gas chromatography:

Column temperature: 35 ℃ of (3 minutes)-5 ℃/minute-70 ℃ of temperature programming; 300 ℃ of heat pipe temperatures;

Sample: gasoline; All the other are with example 2.

Chromatographic fractionation figure is seen Fig. 7, and local chromatogram is seen Fig. 8,9 after amplifying; From Fig. 8,9 as can be seen at post 1 unsegregated chromatographic peak (near 4.4 minutes, 7 minutes, 7.4 minutes, 8.1 minutes, actual is toluene, ethylbenzene, dimethylbenzene and corresponding alkane), because the difference of two column polarities, well separated through very short polar column 2, demonstrate fully the comprehensive two dimensional gas chromatography high score from superiority.

Claims (2)

1. CO ₂Band is pressed the method that purifies liquefaction, it is characterized in that: gas phase CO ₂Be not less than under the 4.0Mpa condition at pressure and purify, remove organic matter, dust and water, and then in ice-water condition band hydraulic fluidization down, it adopts as lower device and finishes: by CO ₂Clarifier b (4), coil pipe (6) and gas resistance gauge (7) that source of the gas (1), pressure gauge (2), interior dress take off the clarifier a (3) of hydrocarbon agent, interior dress dehydrating agent are connected in series by pipeline, wherein: described coil pipe (6) places ice-water-bath (5), and all stops up the stainless (steel) wire of sintering in the outlet of clarifier a (3) and clarifier b (4).

2. the device according to the described method of claim 1 is characterized in that: by CO ₂Clarifier b (4), coil pipe (6) and gas resistance gauge (7) that source of the gas (1), pressure gauge (2), interior dress take off the clarifier a (3) of hydrocarbon agent, interior dress dehydrating agent are connected in series by pipeline, wherein: described coil pipe (6) places ice-water-bath (5), and all stops up the stainless (steel) wire of sintering in the outlet of clarifier a (3) and clarifier b (4).

Images