Summary of the invention
The purpose of this invention is to provide a kind of method and measurement mechanism that coal petrography gases at high pressure adsorbance and adsorption swelling amount are measured simultaneously.
Measuring method concrete operations step of the present invention is as follows:
(1) preparation of test coal petrography sample:
At first coal petrography to be measured is processed into the bulk sample of column type or rectangular build, and guarantees that coal petrography sample upper and lower end face is parallel and smooth, as required the coal petrography sample is carried out equilibrium moisture then and handle or dried, accurately measure the height L of coal petrography sample
0, and accurately take by weighing the weight G of coal petrography sample
0
(2) installation of test coal petrography sample:
At first open the measuring and controlling instrument power supply, start computing machine and operation;
With pack into the sample tube of measurement mechanism of coal petrography sample, the bottom of sample tube with the upper cylinder body of Hi-pot test container is connected, by regulating the position of sample tube, guarantee that the coal petrography sample reliably contacts with the displacement transducer measuring staff that is contained in upper cylinder body; Observe the displacement data that shows on measuring and controlling instrument or the computer screen simultaneously, accurately regulate the zero point of displacement transducer, with stay the bottom and the sample tube of upper cylinder body are fixed, then the sample wound packages is gone into the lower cylinder body of Hi-pot test container, be tightly connected with the upper cylinder body and the lower cylinder body of cutting ferrule with the Hi-pot test container;
(3) work is prepared before the test:
According to experimental program, set the temperature required T of experiment, start and add heat control, thermostatic bath is heated, when treating that the thermostatic bath temperature arrives design temperature T, start vacuum pump and extract high pressure reference container and Hi-pot test container and measuring system inner air, make high pressure reference container and Hi-pot test container and measuring system inside be in vacuum state, stop vacuum pump then, closeall valve;
(4) free space volumes is measured:
Free space volumes is meant the summation of the volume of Hi-pot test container loading coal rock sample product back coal petrography sample interior fine voids, the remaining free space of Hi-pot test container, associated line inner space, helium (H
e) be a kind of not adsorbed gas, measure the free space volumes of Hi-pot test container to the expansion of Hi-pot test container from the high pressure reference container by helium;
Open high-pressure helium (H
e) valve, in system, charge into helium, open air intake valve, to the helium that the high pressure reference container charges into, regulate high pressure reference container pressure to goal pressure, close gas admittance valve then, treat after the pressure stability record high pressure reference container this moment internal pressure P
2With Hi-pot test container internal pressure P
3, open the compensation flap between high pressure reference container and the Hi-pot test container, make helium enter the Hi-pot test container from the high pressure reference container, treat high pressure reference container and Hi-pot test container internal pressure stable equilibrium after, record this moment pressure P
1, obtain one group of data T, P this moment
1, P
2, P
3, calculate the volume V that places the Hi-pot test internal tank free space behind the sample by following formula
F
The free space volumes computing formula is:
V
F=V
R(ρ
R0-ρ
R1)/(ρ
F1-ρ
F0) ——(1)
Wherein: ρ
R0=f (T, P
2) ρ
F0=f (T, P
3)
ρ
R1=ρ
F1=f(T,P
1)
In the formula:
V
F: expression free space volumes, unit are cubic centimetre (cm
3);
V
R: expression high pressure reference container volume (known), unit are cubic centimetre (cm
3);
P
1: pressure after the expression balance, unit is MPa (MPa);
P
2: expression high pressure reference container original pressure, unit is MPa (MPa);
P
3: expression Hi-pot test container original pressure, unit is MPa (MPa);
T: the expression experimental temperature, unit is (K);
ρ
R0: expression high pressure reference container initial gas density, unit is every cubic centimetre of (mmol/cm of mM
3);
ρ
F0: expression Hi-pot test container initial gas density, unit is every cubic centimetre of (mmol/cm of mM
3);
ρ
R1: gas density after the expression high pressure reference container balance, unit is every cubic centimetre of (mmol/cm of mM
3);
ρ
F1: gas density after the expression Hi-pot test container balance, unit is every cubic centimetre of (mmol/cm of mM
3);
After free space volumes has been measured, with the gas emptying, start vacuum pump once more and extract high pressure reference container and Hi-pot test container and measuring system internal gas, make high pressure reference container and Hi-pot test container and measuring system inside be in vacuum state, stop vacuum pump then, closeall valve;
(5) adsorbance and adsorption swelling amount are measured simultaneously:
Open Hi-pot test gas (as CH
4, N
2, CO
2Gas) valve starts the gases at high pressure supercharge pump as required, at first opens gas admittance valve, to the Hi-pot test gas that the high pressure reference container charges into, regulate high pressure reference container pressure to goal pressure, close air intake valve then, after treating pressure stability, record high pressure reference container this moment internal pressure P
5With Hi-pot test container internal pressure P
6Open the compensation flap between high pressure reference container and the Hi-pot test container, make Hi-pot test gas enter the Hi-pot test container from the high pressure reference container, treat high pressure reference container and Hi-pot test container internal pressure stable equilibrium after, record this moment equalized pressure P
4, obtain one group of data T, P this moment
4, P
5, P
6The high pressure content ratio juris has been adopted in the test of adsorbance, measuring and controlling instrument can be calculated the absorption variable quantity (Δ n) and the adsorbance (n) in this equilibrium pressure force by measuring the pressure and the temperature of high pressure reference container and Hi-pot test container adsorption equilibrium front and back by mass balance; Simultaneously in this course, Hi-pot test gas enters after the Hi-pot test container from the high pressure reference container, the coal petrography sample will be because absorption Hi-pot test gas will produce dilatational strain, make the displacement transducer measuring staff to top offset, displacement transducer is converted to electric signal with displacement deformation and sends into measuring and controlling instrument, the expansion height (Δ L) of coal petrography sample be can record simultaneously, adsorbance (n) and adsorption swelling amount (ε) calculated by following formula in this equilibrium pressure force; The computing formula of adsorbance is:
n=Δn
1+Δn
2+Δn
3+....+Δn
i ——(3)
Wherein: ρ
R0=f (T, P
5) ρ
F0=f (T, P
6)
ρ
R1=ρ
F1=f(T,P
4)
Adsorption swelling amount computing formula is:
ε=ΔL/L
0×10
6 ——(4)
More than various in:
Δ n: represent the absorption variable quantity in each equilibrium pressure force, unit is the every gram of mM (mmol/g);
N: represent total adsorbance, unit is the every gram of mM (mmol/g);
G
0: the weight of expression coal petrography sample, unit is gram (g);
Δ L: the expansion height of expression coal petrography sample, unit is a millimeter (mm);
L
0: expression coal petrography sample elemental height, unit is a millimeter (mm);
ε: expression adsorption swelling amount, dimensionless;
V
F: expression free space volumes, unit are cubic centimetre (cm
3);
V
R: expression high pressure reference container volume (known), unit are cubic centimetre (cm
3);
P
4: pressure after the expression balance, unit is MPa (MPa);
P
5: expression high pressure reference container original pressure, unit is MPa (MPa);
P
6: expression Hi-pot test container original pressure, unit is MPa (MPa);
T: the expression experimental temperature, unit is (K);
ρ
R0: expression high pressure reference container initial gas density, unit is every cubic centimetre of (mmol/cm of mM
3);
ρ
F0: expression Hi-pot test container initial gas density, unit is every cubic centimetre of (mmol/cm of mM
3);
ρ
R1: gas density after the expression high pressure reference container balance, unit is every cubic centimetre of (mmol/cm of mM
3);
ρ
F1: gas density after the expression high pressure reference container balance, unit is every cubic centimetre of (mmol/cm of mM
3);
(6) after the adsorption swelling balance, close compensation flap, open gases at high pressure once more (as CH
4, N
2, CO
2Gas) valve, start the gases at high pressure supercharge pump, open gas admittance valve, continue to charge into Hi-pot test gas to high pressure reference container inside, regulate high pressure reference container pressure to next goal pressure, repeat (5) step, carry out the test of next experimental pressure point adsorbance and adsorption swelling amount, like this, test from low and high spot pressure one by one, until last spot pressure off-test, can obtain adsorbance and adsorption swelling amount under the different equalized pressures, i.e. adsorption isothermal and adsorption swelling isotherm; Change system temperature, can measure adsorption isothermal and adsorption swelling isotherm under the different temperatures.
Designed measurement mechanism for finishing the present invention.Measurement mechanism of the present invention is by the Hi-pot test container, the high pressure reference container, and displacement transducer, first pressure unit, second pressure unit, constant temperature bath cabinet and measuring and controlling instrument are formed; The wall that it is characterized in that the constant temperature bath cabinet is equipped with semiconductor chilling plate, in the constant temperature bath cabinet heating tube is housed, ebullator, thermometric thermal resistance, Hi-pot test container and high pressure reference container; The Hi-pot test container is by lower cylinder body, upper cylinder body, cutting ferrule, air intake opening and gas outlet are formed, between upper cylinder body and the lower cylinder body sealing gasket is installed, upper cylinder body and lower cylinder body are connected and sealed by cutting ferrule, at the upper cylinder body top displacement transducer is housed, between displacement transducer and the upper cylinder body sealing gasket is arranged, and be fixed together by fixed part, the measuring staff of displacement transducer passes through upper cylinder body, and be positioned at outside the upper cylinder body bottom, the bottom of upper cylinder body is equipped with sample tube and stay, the sample tube is to be threaded with the bottom of upper cylinder body, stay is fixed together the bottom of sample tube and upper cylinder body, the bleeder vent that is evenly distributed is arranged on the sample tube, lower cylinder body has air intake opening and gas outlet, at high pressure reference container top second pressure unit is arranged, between the high pressure reference container and second pressure unit air intake opening and gas outlet are arranged, air intake opening between the high pressure reference container and second pressure unit is equipped with gas admittance valve, vent valve is equipped with in gas outlet at lower cylinder body, and the equalizing valve and first pressure unit are housed between Hi-pot test container and high pressure reference container; Displacement transducer, first pressure unit, second pressure unit, heating tube, ebullator, semiconductor chilling plate is connected with measuring and controlling instrument by cable with the thermometric thermal resistance.
Described Hi-pot test container and high pressure reference container, its material are stainless steel, and be withstand voltage greater than 30MPa.
Described displacement transducer is that model is a kind of high pressure resistant linear variable differential transformer (LVDT) formula displacement transducer (LVDT) of GA-2, this displacement transducer body and iron core measuring staff are integral structure, have guiding and resilience function, the back springing type structure can avoid measuring staff owing to friction can't reliably contact the measuring error that causes with measuring samples, improves measuring accuracy; This displacement transducer is withstand voltage greater than 30MPa, and measuring accuracy is 0.05%, and measurement range is 0-2mm, and displacement transducer is converted to electric signal with the expansion or the drawdown deformation of measured coal petrography sample, delivers to measuring and controlling instrument and carries out signal Processing and analog to digital conversion.
Described pressure unit is that model is a kind of high-voltage intelligent pressure unit of MPM421, it is withstand voltage greater than 30MPa, measuring accuracy is 0.1%FS, and measurement range is-0.1-20MPa that pressure unit is used to measure the internal pressure of Hi-pot test container and high pressure reference container.
Used heating medium is water or glycerine in the described constant temperature bath cabinet; The working temperature of thermostatic bath is 0-80 ℃, and temperature-controlled precision is 0.1 ℃.
Described thermometric thermal resistance is the Pt100 platinum resistance.
Described measuring and controlling instrument has been used the single chip computer measurement control technology, includes the displacement transducer signal data acquisition circuit, thermometric thermal resistance signal data acquisition circuit, pressure unit signal data acquisition circuit, temperature-control circuit, display circuit, data communication circuit and single-chip microcomputer; Pressure unit, the electric signal of displacement transducer and thermometric thermal resistance is delivered to data acquisition circuit separately, under the control of single-chip microcomputer, by data acquisition circuit to displacement transducer, the thermometric thermal resistance, the electric signal of pressure unit carries out signal transformation and analog to digital conversion, shows the temperature of thermostatic bath in real time by display circuit, the expansion height of Hi-pot test container and high pressure reference container internal pressure and coal petrography sample; Wherein the PID control technology is adopted in temperature control, by temperature-control circuit control heating tube 8, and semiconductor chilling plate, the work of ebullator is carried out temperature control to thermostatic bath; The temperature of being gathered simultaneously, pressure and displacement data are directly sent into computing machine through the data communication circuit, and the RS232 serial communication mode is used in Computer Data Communication, and this measuring and controlling instrument is connected with the RS232 serial line interface of computing machine by RS232 communication lead.
The computing machine automatic reception is from the experimental temperature of measuring and controlling instrument, pressure and displacement signal data, the data that receive are write down and preserve, automatically calculate adsorbance and adsorption swelling amount, and on computer screen, show the temperature in the experimentation in real time, pressure, adsorbance and swell increment data, and show pressure in real time, temperature and swell increment be law curve over time.
Coal petrography gases at high pressure adsorbance provided by the present invention and simultaneously-measured method of adsorption swelling amount and measurement mechanism can be at pressure 0-20MPa, in temperature 0-80 ℃ the scope, measure automatically simultaneously coal petrography at gases at high pressure (as CH
4, N
2, CO
2Gas) adsorbance in and adsorption swelling amount.In measuring process, measuring and controlling instrument is to displacement transducer, the thermometric thermal resistance, and the electric signal of pressure unit carries out signal transformation and analog to digital conversion, shows experimental pressure in real time, the displacement signal data that the expansion of temperature and sample changes.The computing machine automatic reception is from the pressure of measuring and controlling instrument, temperature and displacement signal data, the data that receive are write down and preserve, automatically calculate adsorbance and adsorption swelling amount, on computer screen, show the pressure in the experimentation in real time, temperature, adsorbance and swell increment data, and show pressure in real time, temperature and swell increment be law curve over time.
Coal petrography gases at high pressure adsorbance provided by the present invention and simultaneously-measured method of adsorption swelling amount and measurement mechanism also can be widely used in other field, are used for test and the research of other porous mass in the adsorbance and the adsorption swelling amount of gases at high pressure.
The present invention has the following advantages:
1, can disposablely finish the measurement of adsorbance and adsorption swelling amount, more easy than existing additive method, quick.
2, use same specimen to measure adsorbance and adsorption swelling amount simultaneously, can reflect the relation of influencing each other between them better.
3, adopt the bulk sample coal sample of cylindrical or rectangular build, test findings helps comparing with conventional rock mechanics standard, has higher utility.
4, displacement sensor adsorption swelling amount, what the measurement of adsorbance was adopted is the high pressure content ratio juris, directly utilizes the swell increment test container as the sample cylinder in the high pressure content method absorption measurement, measures the adsorption swelling amount when measuring adsorbance.
Measure when 5, not only can be used for adsorbance and adsorption swelling amount, obtain adsorption isothermal and adsorption swelling isotherm.Measure when also can be used for desorption rate and desorption amount of contraction, obtain desorption isotherm and desorption and shrink isotherm.
Measure when 6, not only can be used for adsorbance and adsorption swelling amount, also can be used for independent measurement adsorbance or independent measurement adsorption swelling amount.
7, have simple in structurely, high pressure sealing is reliable and secure, easy operating, measuring accuracy height, withstand voltage height, the advantage of measuring automatically.
Description of drawings:
Fig. 1, be coal petrography gases at high pressure adsorbance and the adsorption swelling amount structural representation of measurement mechanism simultaneously
Fig. 2, be coal petrography gases at high pressure adsorbance and the adsorption swelling amount circuit diagram of measurement mechanism simultaneously
Fig. 3, be coal petrography gases at high pressure adsorbance and adsorption swelling amount simultaneously measurement mechanism use synoptic diagram
Fig. 4, be temperature under 45 ℃ of conditions, a kind of Yangquan coal petrography sample of surveying at CO
2The relation curve of the adsorbance in the gas and adsorption swelling amount and equalized pressure.
Fig. 5, be under 65 ℃ of conditions, a kind of Yangquan coal petrography sample of surveying at CH
4The relation curve of the adsorbance in the gas and adsorption swelling amount and equalized pressure.
Fig. 6, be under 25 ℃ of conditions, a kind of Yangquan coal petrography sample of surveying at N
2The relation curve of the adsorbance in the gas and adsorption swelling amount and equalized pressure.
As shown in the figure: the 1st, Hi-pot test container, the 2nd, high pressure reference container, the 3rd, displacement transducer, 4 second pressure units, 5 is first pressure units, the 6th, and column type sample tube, the 7th, stay, the 8th, heating tube, the 9th, thermometric thermal resistance, the 10th, bottom cylinder body, the 11st, top cylinder body, the 12nd, cutting ferrule, the 13rd, fixed part, the 14th, sealing gasket, the 15th, coal petrography sample, the 16th, semiconductor chilling plate, the 17th, ebullator, the 18th, thermostatic bath, the 19th, constant temperature bath cabinet, the 20th, gas admittance valve, the 21st, equalizing valve, the 22nd, vent valve, the 23rd, measuring and controlling instrument, 24,25,29,31st, by-pass valve control, the 26th, vacuum pump, the 27th, computing machine, the 28th, high-pressure helium (He) steel cylinder, the 30th, Hi-pot test gas bomb, the 32nd, supercharge pump, the 33rd, fixed head, the 34th, sealing gasket.
Embodiment
Be described in detail below in conjunction with embodiment illustrated in fig. 3 the specific embodiment of the present invention is done further.
Embodiment 1:
Measurement mechanism is by Hi-pot test container 1, high pressure reference container 2, displacement transducer 3, the first pressure units 5, the second pressure units 4, constant temperature bath cabinet 19 and measuring and controlling instrument 23 are formed, the wall of constant temperature bath cabinet 19 is equipped with semiconductor chilling plate 16, and heating tube 8 is equipped with in constant temperature oven 19 inside, thermometric thermal resistance 9, ebullator 17, Hi-pot test container 1 and high pressure reference container 2; Hi-pot test container 1 is by lower cylinder body 10, upper cylinder body 11, cutting ferrule 12, air intake opening and gas outlet are formed, between upper cylinder body 11 and the lower cylinder body 10 sealing gasket 14 is installed, upper cylinder body 11 is connected and fixed by cutting ferrule 12 with lower cylinder body 10, at upper cylinder body 11 tops displacement transducer 3 is housed, sealing gasket 34 is housed between displacement transducer 3 and the upper cylinder body 11 and is fixed together by fixed part 13, the bottom of upper cylinder body 11 is equipped with column type sample tube 6 and stay 7, column type sample tube 6 is to be threaded with the bottom of upper cylinder body 11, and stay 7 is connected and fixed the bottom of column type sample tube 6 with upper cylinder body 11, on the column type sample tube 6 bleeder vent that is evenly distributed is arranged; At high pressure reference container 2 tops second pressure unit 4 is arranged, between the high pressure reference container 2 and second pressure unit 4 air intake opening and gas outlet are arranged, air intake opening between the high pressure reference container 2 and second pressure unit 4 is equipped with gas admittance valve 20, in the gas outlet of lower cylinder body 10 vent valve 22 is housed, the equalizing valve 21 and first pressure unit 5 are housed between Hi-pot test container 1 and high pressure reference container 2; Displacement transducer 3, the first pressure units 5, the second pressure units 4, heating tube 8, ebullator 17, semiconductor chilling plate 11 is connected with measuring and controlling instrument 23 by cable with thermometric thermal resistance 9.
The material of Hi-pot test container 1 is a stainless steel, and is withstand voltage greater than 30MPa.Displacement transducer 3 is that model is the high pressure resistant linear variable differential transformer (LVDT) formula displacement transducer of GA-2, first pressure unit 5 and second pressure unit 4 are that model is the high-voltage intelligent pressure unit of MPM421, thermometric thermal resistance 9 is the Pt100 platinum resistance, and constant temperature bath cabinet 19 used heating mediums are water or glycerine.
Measuring and controlling instrument 23 has been used the single chip computer measurement control technology, comprises the displacement transducer signal data acquisition circuit, thermometric thermal resistance signal data acquisition circuit, pressure unit signal data acquisition circuit, temperature-control circuit, display circuit, data communication circuit and single-chip microcomputer; First pressure unit 5, second pressure unit 4, the electric signal of displacement transducer 3 and thermometric thermal resistance 9 is delivered to data acquisition circuit separately, under the control of single-chip microcomputer, data acquisition circuit is with first pressure unit, 5, the second pressure units 4, and the electric signal of displacement transducer 3 and thermometric thermal resistance 9 carries out signal transformation and analog to digital conversion, show the temperature of thermostatic bath in real time by display circuit, the expansion height of high pressure reference container 2 and Hi-pot test container 1 internal pressure and sample; Wherein the PID control technology is adopted in temperature control, by temperature-control circuit control heating tube 8, and ebullator 17, the work of semiconductor chilling plate 16 is carried out temperature control to thermostatic bath 18; The temperature of being gathered simultaneously, pressure and displacement data are directly sent into computing machine 27 through the data communication circuit, the RS232 serial communication mode is used in Computer Data Communication, and measuring and controlling instrument 23 is connected with the RS232 serial line interface of computing machine 27 by RS232 communication lead.
Narrate adsorbance and adsorption swelling amount measuring process simultaneously below:
Earlier measurement mechanism is connected according to mode shown in Figure 3.
At first Yangquan to be measured coal petrography is processed into the bulk sample of column type or rectangular build, and guarantees that coal petrography sample 15 upper and lower end faces are parallel and smooth,, accurately measure the height (L of coal petrography sample coal petrography sample dry 12h under 110 ℃ of vacuum conditions of temperature
0), and accurately take by weighing the weight (G of coal petrography sample
0), sealing is preserved stand-by.
Open measuring and controlling instrument 23 power supplys, start computing machine 27.With the coal petrography sample 15 column type sample tube 6 of packing into fast, column type sample tube 6 is connected with the top cylinder body 11 of Hi-pot test container 1, guarantee that coal petrography sample 15 reliably contacts with the measuring staff of displacement transducer 3, regulate the height of column type sample tube 6, observe the displacement data that shows on measuring and controlling instrument or the computer screen simultaneously, accurately regulate the zero point of displacement transducer, with stay 7 fixed cylinder type sample tubes 6, the bottom cylinder body 10 of then top cylinder body 11 being packed into will be gone up lower cylinder body with cutting ferrule 12 and be connected and fixed.
Design temperature is 45 ℃ (T) for experiment is temperature required, start and add heat control, thermostatic bath 18 is heated, treat that thermostatic bath 18 temperature arrive design temperature (45 ℃), close all valves, open equalizing valve 21, air release 22 and vacuum valve 25 start vacuum pump 26 and extract high pressure reference container 2 and Hi-pot test container 1 and internal system air.Close equalizing valve 21 then, air release 22 and vacuum valve 25 stop vacuum pump 26.
Open helium (He) steel cylinder 28 valves and helium stop valve 29, start gases at high pressure supercharge pump 32 and charge into helium to system.Open gas admittance valve 20, charge into a certain amount of helium to high pressure reference container 2, second pressure unit 4 is used to measure high pressure reference container 2 internal pressures, regulate high pressure reference container 2 pressure to goal pressure, close gas admittance valve 20 then, treat pressure stability, record high pressure reference container this moment 2 internal pressure (P
2) and Hi-pot test container 1 internal pressure (P
3); Open the equalizing valve 21 between high pressure reference container 2 and the Hi-pot test container 1, make helium enter Hi-pot test container 1 from high pressure reference container 2, first pressure unit 5 is used to measure Hi-pot test container 1 internal pressure, after treating high pressure reference container 2 and Hi-pot test container 1 internal pressure stabilises balance, record pressure (P this moment
1), by measuring and controlling instrument 23 acquisition system temperature (T) and pressure (P
1), (P
2) and (P
3) signal, carry out data processing by computing machine 27, calculate the Hi-pot test container 1 internal freedom spatial volume (V that places behind the coal petrography sample
F); Emptying system then, start vacuum pump 26 once more and extract high pressure reference container 2 and Hi-pot test container 1 and internal system gas, make high pressure reference container 2 and Hi-pot test container 1 and internal system be in vacuum state, stop vacuum pump 26 then, closeall valve.Free space volumes specifically calculates:
The data that record:
T=45+273.15=318.45(K) P
1=0.965(MPa) P
2=1.280(MPa)
P
3=0.000(MPa) V
R=176.74(cm
3)
ρ
R1=ρ
F1=f(T,P
1)=0.3633(mmol/cm
3)
ρ
R0=f(T,P
2)=0.4813(mmol/cm
3)
ρ
F0=f(T,P
3)=0.0000(mmol/cm
3)
Calculate and can get by formula (1):
V
F=V
R(ρ
R0-ρ
R1)/(ρ
F1-ρ
F0)=57.41(cm
3)
Open Hi-pot test gas (CO
2Gas) steel cylinder 30 valves and stop valve 31 start gases at high pressure supercharge pump 32, charge into Hi-pot test gas (CO to internal system
2Gas); Open gas admittance valve 20, charge into a certain amount of Hi-pot test gas to high pressure reference container 2, second pressure unit 4 is used to measure high pressure reference container 2 internal pressures, regulates high pressure reference container 2 pressure to goal pressure, closes gas admittance valve 20 then; Treat pressure stability, record high pressure reference container this moment 2 internal pressure (P
5) and Hi-pot test container 1 internal pressure (P
6); Open the equalizing valve 21 between high pressure reference container 2 and the Hi-pot test container 1, make Hi-pot test gas enter Hi-pot test container 1 from high pressure reference container 2, first pressure unit 5 is used to measure Hi-pot test container 1 internal pressure, after treating high pressure reference container 2 and Hi-pot test container 1 internal pressure stabilises balance, record equalized pressure (P this moment
4); This moment is by measuring and controlling instrument 23 acquisition system temperature (T) and pressure (P
4), (P
5) and (P
6) signal, carry out data processing by computing machine 27.According to pressure and the temperature before and after high pressure reference container 2 and Hi-pot test container 1 balance, can obtain adsorbance (the Δ n in this equilibrium pressure force
1) and adsorbance (n).
In this course, Hi-pot test gas enters from high pressure reference container 2 after the Hi-pot test container 1, and coal petrography sample 15 is because absorption Hi-pot test gas (CO
2Gas) will produce dilatational strain, and make displacement transducer 3 measuring staffs to top offset, displacement transducer 3 is converted to electric signal with displacement deformation, delivers to measuring and controlling instrument 23 and carries out signal Processing and analog to digital conversion.Computing machine 27 automatic receptions are from the experimental pressure of measuring and controlling instrument 23, temperature and displacement signal data, the data that receive are write down and preserve, and on computer screen, show the pressure in the experimentation in real time, temperature and expansion data, and swell increment law curve over time.After the adsorption swelling balance, can record expansion height (the Δ L of coal petrography sample simultaneously in this equilibrium pressure force
1) and adsorption swelling amount (ε).
The concrete calculating of adsorbance and adsorption swelling amount:
T=45+273.15=318.45(K) L
0=68.70(mm) G
0=18.8527(g)
P
4=0.425(MPa) P
5=0.780(MPa) P
6=0.000(MPa)
V
R=176.74(cm
3) ρ
R1=ρ
F1=f(T,P
4)=0.1635(mmol/cm
3)
ρ
R0=f(T,P
5)=0.3046(mmol/cm
3) ρ
F0=f(T,P
6)=0.0000(mmol/cm
3)
V
F=57.41(cm
3) ΔL
1=0.1308(mm)
Calculate and can get by formula (2):
Calculate and can get by formula (3):
n=Δn
1=0.8249(mmol/g)
Calculate and can get by formula (4):
ε=ΔL
1/L
0×10
6=1904
After the adsorption swelling balance, close equalizing valve 21; Open gases at high pressure (CO once more
2Gas) steel cylinder 30 valves and valve 31, start gases at high pressure supercharge pump 32, open gas admittance valve 20, continue to charge into Hi-pot test gas to high pressure reference container 2 inside, regulate high pressure reference container 2 pressure to next goal pressure, repeat above step, carry out the test of next experimental pressure point adsorbance and adsorption swelling amount., test, until last spot pressure off-test from low and high spot pressure one by one like this.Can obtain adsorbance and adsorption swelling amount under the different pressures, i.e. adsorption isothermal and adsorption swelling isotherm.Change system temperature, can measure adsorption isothermal and adsorption swelling isotherm under the different temperatures.
Embodiment 2:
Design temperature is at 65 ℃, and Hi-pot test gas is CH
4Under the condition of gas, all the other are with embodiment 1.
Embodiment 3:
Design temperature is at 25 ℃, and Hi-pot test gas is N
2Under the condition of gas, all the other are with embodiment 1.