Some standard content:
Industry Standard of the People's Republic of China
Test method of ammonia synthesis catalyst
Determination of amnonia synthesis catalyst 1 Subject content and applicable scope]
ZB G 74002-90
This standard specifies the test methods for the activity, main physical properties and chemical components of ammonia synthesis catalysts. This standard is applicable to A106, A109, A110 (A110-1, A110--2, A110-3, A110-4, A310-5Q, A110-6) series ammonia synthesis catalysts for the reaction of hydrogen and nitrogen to produce ammonia. 2 Reference standards
GB 603
GB5205
GB 6003
GB6285
HG3-1215
HG1-1430
3 Activity test
Chemical reagents Preparation of standard solutions for titration analysis (volumetric analysis) Preparation of preparations and products used in chemical reagent test methods Classification and naming of fertilizer catalyst products
Determination of micro-water content in gas Dew point method
Test sieve
Determination of trace oxygen in gas Electrochemical method
Chemical reagents General rules for analysis of trace sulfur
Analysis methods for chemical composition of ammonia synthesis catalysts 3.1 Activity test principle
Hydrogen and nitrogen mixed gas is synthesized into ammonia under the action of catalyst. Under the test conditions specified in this standard, the catalytic efficiency of the catalyst is identified by determining the volume percentage of ammonia at the reactor outlet. The chemical reaction equation is as follows: 3H, + N, 2
3.2 Activity Test Procedure
Ministry of Chemical Industry of the People's Republic of China Issued on March 15, 1990 10-
1991--01-01·Implementation
ZB G 7400290
1 Schematic diagram of the test flow of hydrogen synthesis accompaniment with factory gas as feed gas 1--1~3 pressure gauge 2-1~2 pressure drop valve 3 pressure regulating valve 4 purification system 5. Reactor for analysis
3.2.1 The test flow of the hydrogen synthesis accompaniment with factory gas as feed gas is shown in Figure 1. The hydrogen and nitrogen mixed gas is taken from the synthesis workshop of the fertilizer plant as supplementary gas. After the gas is purified, it is sent to the five reactors for synthesis reaction. The gas after the reaction enters the analysis system and is analyzed for nitrogen content.
2 The test flow of ammonia synthesis accompaniment with the raw gas being ammonia cracking gas is shown in Figure 1. 1-stage flushing bottle 2 cracking furnace 3 purification system 4 compressor 5 reactor 11
ZB G 74002-90bzxz.net
3.2.2 The test flow of the ammonia synthesis catalyst activity test device with the raw gas being ammonia cracking gas is shown in Figure 2. The liquid ammonia in the liquid oxygen cylinder enters the ammonia cracking furnace after the positive pressure reduction, and the hydrogen-nitrogen mixed gas obtained by cracking is decomposed and then enters the membrane compressor for compression. The gas is compressed and enters the five-tank reactor. After the synthesis reaction, the gas enters the analysis system to analyze the ammonia content. The product base must use ammonia cracking gas 32.3. The performance test conditions are: Back-pull: This standard uses a dead reactor, the reaction tube diameter is @12mm, and the optimization agent is loaded: 2.0ml. Catalyst particle size: 1.0--1.4ml meets the basic aperture of the sieve hole of GB6003-85 R40/3 series aperture size, back pressure: 15MPa.
3.0×10h-1
Air avoidance:
Live silk temperature: 475℃ (A196 type), 450 (A109 type), 425℃ (A110 bottle) Heat and humidity resistance: 550℃ (A106 type), 525℃ (A109 type) 500℃ (A110 type) Heat resistance: 10M
Melting time: 20h.|| tt||Raw material composition: acetylene nitrogen ratio is 2.8~3.1
3.2,4 Control test process
3.2.4.1 Preparation of samples and filling of five-stage reactors Crush the chemical test sample and sieve it with a test sieve with a pore size of 1.0~1.4mm. Use a 10ml measuring tube to compact 10.m1 of the sample and weigh it to obtain the density. Then weigh the sample equivalent to 2.0ml of mass. Place a steel mesh on the bottom of each reactor tube, put the treated 1.0-1.4mm quartz sand into the reactor, fill it with a layer of wire mesh with a specified depth, and then pour the treated test piece into the tube, gently hit the wall of the reactor, and then fill the layer of wire mesh with a layer of wire mesh. Finally, fill the 1.0-1.4mm quartz sand with the highest quality, gently compact it, seal it with a mesh, tighten the flange screws, and connect it to the system. 3.2.4.2
Test
Connect the reactor to the system, close the door and vent, fill the reactor with hydrogen, and raise the pressure to 15MPa. Use water to pass through each joint. If there is condensed gas, it should be treated. If the leak test is qualified, the gas inside is usually good, and the thermocouple is placed in the thermocouple sleeve so that its hot end is located at the gas outlet catalyst layer. Push each part. 32.4.3 The original ZB.G-74002- was introduced into the five-cylinder reactor with hydrogen and nitrogen, the space velocity was 3.0×10%-1, the system pressure was normal pressure (A106 type), 5MPa (A109 type, A110 type), and the temperature rise and reduction operating indicators were shown in Table 1, Table 2, and Table 3 respectively. Table 1 A106 type chlorine synthesis catalyst reduction operating indicator temperature range (C)
Hot temperature -350
3.30-~400
450--475
475--500
500—-525
Heating rate (c/h)
Time (h)
16m-20
2A109 type hydrogen synthesis catalyst reduction operation index 2
Temperature range ()
Room temperature-350
350—400
400-450|| tt||450-475
Heating rate (./h)
When the sea. a)
ZBG74002-90
Table 3A110 series fluorine synthesis catalyst reduction operation index temperature range (℃)
Room full-350
350-450
45---75
The original Chen should be expressed as follows
Heating rate ( /h)
Fe,O+H, - 3FeO+H,O
FcO+H2 Fe+H,O
Fe.O,+4H, - 3Fe+4H20
Time required (h)
525℃ (A106 type).475℃ (A109 type), 500℃ (A110 type) After the constant temperature is completed, the pressure is slowly increased to 15MPz within 1h, and the blueness is controlled at 525 (A106 type), 475℃ (A109 type), 500℃ (A110 type), and the space velocity is adjusted to 3.0×10-), and after the conditions stabilize at 1.52, start analyzing the composite volume at the outlet of the five-tank reactor, and then start analyzing every 1.5-2h until the extreme difference signal is less than or equal to 0.3% for three consecutive analyses, and the reduction is completed.
3.2.4,4 Heat-resistant activity of the catalyst
After the catalytic reduction is completed, the catalyst test temperature is controlled at 475℃ (A306 type), 450℃ (A109 type), 425℃ (A110 type), pressure 15MPa, space velocity 3.0×10h and maintained for 1.5-2h, then analyze the ammonia volume of the reactor outlet, and then analyze it every 1.5-25 days until the extreme difference of the outlet complex content is less than or equal to 0.3% for three consecutive analyses. Take the average value of the three determinations as the test result. 3.2.4.5 Heat-resistant activity determination
After the acid-heat-resistant activity determination is completed, raise the catalyst heat-resistant temperature to within 2m 550℃ (A106 type), 525℃ (A109 type, 500℃ (A110 type), keep constant temperature for 20h under the condition of pressure of 10MPs and air velocity of 3.0×10h-1, cool to 475t (A106 type), 450℃ (A109 type), 425℃ (A110 type) within 2h, wait for the condition to stabilize for 1.5-2h before analyzing the hydrogen content at the outlet after heat resistance, and then analyze it every 1.5-2h until the extreme difference of the outlet content is less than or equal to 0.3% for three consecutive analyses, and take the average value of the three measurements as the test result. 3.2.4.6 Analysis method of ammonia volume fraction content and air velocity calculation 14
ZB G 74002-00
Absorption double liquid degree C, so,) = 1.0mol/L sulfur set standard titration solution (prepared and calibrated according to GB601) 20ml in the test tube, add methyl red indicator (prepared according to GB603) ~ 3 drops, then add distilled water to dilute to two-thirds of the test tube, the solution is red, start ventilation and absorption while shaking the stopwatch to record the ventilation time, stop ventilation when the solution turns orange-yellow, read the residual gas volume, ventilation absorption time and the temperature of the wet flowmeter at that time (each sample is allowed to calibrate the air velocity once), calculate the ammonia content according to formula 5, calculate the air velocity according to formula 6, X
22.081 ×C× Vh,50.
V×K+22.081 ×C×V
V - 3.6 × 105
Where: C
× 100
The actual concentration of free carboxylic acid in standard sulfuric acid titration, 0.01/L; The volume of sulfuric acid standard titration solution, ml
The volume of residual gas measured by condensation flow meter, ml; The volume percentage of chlorine, %;
\The volume of catalyst,;
The ventilation absorption time, 3
Space velocity, h\:
The molar volume of ammonia under standard conditions, /mol; The volume conversion coefficient when measuring the system can be calculated by formula 7PP
760 × 133.32 × (1 +
Maximum hydrogen pressure during the test, Pa;
Temperature of the wet flowmeter,;
~Partial pressure of saturated water vapor at the wet flowmeter temperature at that time, Pa3.2.4.7After the test, cut off the heating power supply, close the reactor air inlet valve, and when the temperature of the pentasaccharide reactor drops to room temperature, remove the reactor and separate the catalyst from the quartz sand. The quartz sand is retained after treatment, and the catalyst is discarded. 3.3 Method for determining the parallelism and repeatability of the five-tank reactor The parallelism and repeatability of the five-tank reactor are the key to the determination of catalyst activity. When the activity is abnormal, the parallelism and repeatability of the pentasaccharide reactor need to be determined. Under normal circumstances, the determination is carried out once a year. The determination method is the same as 3.2.4.4, 3.2.4.5, and 3.2.4.6 of this standard, which stipulates that the range of parallelism determination should be less than or equal to 0.3%, and the range of repeatability determination should be less than or equal to 0.5%. 4 Chemical component test method
According to HG1-1430 According to the regulations, the analysis is carried out.
ZB G 74002-90
Thanks A
Determination of the isothermal zone of the pentasaccharide reaction
(Supplementary)
A1 In order to test the activity of the catalyst, the catalyst must be installed in the isothermal zone of the five-tank reactor. Therefore, the isothermal zone of the newly made or replaced five-tank reactor must be tested. The verification cycle is one year. A2 First, a layer of fine copper wire is placed on the sieve plates of the four reaction tubes of the five-tank reactor, and then filled with 1.0-1.4m3 of quartz sand, tighten the nuts, connect the five-tank reactor to the process of the activity test device, and insert the thermocouple into the thermocouple sleeve. After everything is ready, start to raise the temperature. A3 Pass hydrogen and nitrogen into the five-tank reactor at a pressure of 15MPa and an air velocity of 3.0×10h-. Raise the temperature of the reactor to 425 at a rate of about 200℃ per hour. After keeping the temperature constant for 2h, start to measure the isothermal zone. A4 Insert the thermocouple into the bottom of the thermocouple sleeve, record its length and corresponding temperature as the temperature at the origin, first pull the thermocouple outward, wait for about one minute for every 10mm pulled out, and record the humidity after stabilization until the temperature difference is more than 2°C. Then insert the thermocouple into the thermocouple sleeve, wait for about one minute for every 10mm inserted, and record the temperature after stabilization until the thermocouple is inserted to the origin. A5 Repeat the measurement once according to the method of A-, and take the common isotherm of the two measurements as the isotherm at this temperature. A6 Raise the mixing temperature of the five-sugar reactor to 500°C, stabilize it for 2h, and measure the isotherm at 500°C according to the methods of A4 and A5, and take the common isotherm of 425°C and 500C as the isotherm of the five-tank reactor. A7 When the temperature does not show the isothermal zone, remove the pentasaccharide reactor, adjust the density of the electric furnace wire, and then re-measure the isothermal zone to make the temperature difference in the isothermal zone less than or equal to 1°C, and the length of the isothermal zone should be greater than or equal to 40mm.
A8 Based on the measured length of the isothermal zone, determine the height of the quartz sand filled at the bottom of the five-tank reactor and the catalyst filling position, and calculate the length of the thermocouple insertion. 53 G 74002-50
Determination of the degree of catalysis
(supplement)
31 Divide the sieved sample of 1.0-1.4mm. into ten portions and add them into a 10nml measuring cylinder according to the volume. Each time adding, move the cylinder up and down until the position of the sample in the measuring cylinder remains unchanged. Repeat the operation until the maximum test volume is 10ml.
B2 Use a balance to weigh the sample and lift the cylinder. Weigh 0.1% 83 Interpretation method
The bulk density (g/ml) of the catalyst is calculated according to formula B1: (B1)
-bulk density, g/ml;
m-mass of 10ml measuring cylinder, g,
m-mass of 10m measuring cylinder such as m1 test sample, g:-product of test sample, ml.
B4 Take the average of two parallel measurement results with relative error <0.2% as the measurement result, 17
0×10h-, raise the temperature of the reactor to 425 at a rate of about 200℃ per hour, keep the temperature constant for 2h, and then start to measure the isothermal zone. A4 Insert the thermocouple into the bottom of the thermocouple sleeve, record its length and corresponding temperature, as the temperature at the origin, first pull the thermocouple outward, wait for about one minute for every 10mm pulled out, and record the humidity after stabilization until the temperature difference is more than 2c. Then insert the thermocouple into the thermocouple sleeve, wait for about one minute for every 10mm inserted, and record the temperature after stabilization until the thermocouple is inserted to the origin. A5 Repeat the measurement once according to the method of A-, and take the common isothermal zone of the two measurements as the isothermal zone at this temperature. A6 Raise the temperature of the pentasaccharide reactor to 500℃, stabilize it for 2h, and measure the isothermal zone at 500℃ according to the methods of A4 and A5, and take the common isothermal zone of 425℃ and 500C as the isothermal zone of the five-tank reactor. A7 When the temperature does not show the isothermal zone, remove the pentasaccharide reactor, adjust the density of the electric furnace wire, and then re-measure the isothermal zone to make the temperature difference in the isothermal zone less than or equal to 1°C, and the length of the isothermal zone should be greater than or equal to 40mm.
A8 Based on the measured length of the isothermal zone, determine the height of the quartz sand filled at the bottom of the five-tank reactor and the catalyst filling position, and calculate the length of the thermocouple insertion. 53 G 74002-50
Determination of the degree of catalysis
(supplement)
31 Divide the sieved sample of 1.0-1.4mm. into ten portions and add them into a 10nml measuring cylinder according to the volume. Each time adding, move the cylinder up and down until the position of the sample in the measuring cylinder remains unchanged. Repeat the operation until the maximum test volume is 10ml.
B2 Use a balance to weigh the sample and lift the cylinder. Weigh 0.1% 83 Interpretation method
The bulk density (g/ml) of the catalyst is calculated according to formula B1: (B1)
-bulk density, g/ml;
m-mass of 10ml measuring cylinder, g,
m-mass of 10m measuring cylinder such as m1 test sample, g:-product of test sample, ml.
B4 Take the average of two parallel measurement results with relative error <0.2% as the measurement result, 17
0×10h-, raise the temperature of the reactor to 425 at a rate of about 200℃ per hour, keep the temperature constant for 2h, and then start to measure the isothermal zone. A4 Insert the thermocouple into the bottom of the thermocouple sleeve, record its length and corresponding temperature, as the temperature at the origin, first pull the thermocouple outward, wait for about one minute for every 10mm pulled out, and record the humidity after stabilization until the temperature difference is more than 2c. Then insert the thermocouple into the thermocouple sleeve, wait for about one minute for every 10mm inserted, and record the temperature after stabilization until the thermocouple is inserted to the origin. A5 Repeat the measurement once according to the method of A-, and take the common isothermal zone of the two measurements as the isothermal zone at this temperature. A6 Raise the temperature of the pentasaccharide reactor to 500℃, stabilize it for 2h, and measure the isothermal zone at 500℃ according to the methods of A4 and A5, and take the common isothermal zone of 425℃ and 500C as the isothermal zone of the five-tank reactor. A7 When the temperature does not show the isothermal zone, remove the pentasaccharide reactor, adjust the density of the electric furnace wire, and then re-measure the isothermal zone to make the temperature difference in the isothermal zone less than or equal to 1°C, and the length of the isothermal zone should be greater than or equal to 40mm.
A8 Based on the measured length of the isothermal zone, determine the height of the quartz sand filled at the bottom of the five-tank reactor and the catalyst filling position, and calculate the length of the thermocouple insertion. 53 G 74002-50
Determination of the degree of catalysis
(supplement)
31 Divide the sieved sample of 1.0-1.4mm. into ten portions and add them into a 10nml measuring cylinder according to the volume. Each time adding, move the cylinder up and down until the position of the sample in the measuring cylinder remains unchanged. Repeat the operation until the maximum test volume is 10ml.
B2 Use a balance to weigh the sample and lift the cylinder. Weigh 0.1% 83 Interpretation method
The bulk density (g/ml) of the catalyst is calculated according to formula B1: (B1)
-bulk density, g/ml;
m-mass of 10ml measuring cylinder, g,
m-mass of 10m measuring cylinder such as m1 test sample, g:-product of test sample, ml.
B4 Take the average of two parallel measurement results with relative error <0.2% as the measurement result, 17
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