The measurement accuracy of the bituminous coal gelatinous layer index tester is high

The measurement accuracy of the bituminous coal gelatinous layer index tester is high

The measurement technique of the gelatinous layer index of bituminous coal is an important technology in the field of coal analysis, which is of great significance for evaluating the coking and bonding properties of bituminous coal and guiding coal blending and coking.

nowProvide a detailed introduction to the principles, methods, techniques, and precautions for determining the gelatinous layer index of bituminous coal, aiming to help readers better grasp this technology and improve the accuracy and reliability of the measurement results.

one

Principle of measuring glial layer index

The determination principle of the gelatinous layer index of bituminous coal is based on the temperature gradient formed by the coal sample under unidirectional heating conditions. Load the coal sample into a specially designed coal cup and place it in an electric furnace with unidirectional heating at the bottom. After heating, the coal sample gradually forms a series of horizontal isothermal layers. As the temperature increases, certain parts of the coal sample begin to soften and melt, forming a gelatinous bodyAnd the parts with higher temperatures gradually solidify to form semi coke. By measuring the distance between the upper and lower layers of the glial body with a probe, the thickness of the glial layer can be obtained; At the same time, recording the volume change curve of the coal sample after heating can determine the final shrinkage degree.

two

Preparation before measurement

1. Preparation of coal samples:Select representative coal samples, crush and mix them to ensure their uniformity. When loading the coal sample into the coal cup, the cone quartering method should be used to ensure even distribution of the coal sample in the cup.

2. Equipment inspection:Check whether the coal cup, thermocouple iron pipe, pressure plate and other components are clean and free of coke residue. Use diamond gauze or cleaning machinery to remove residues and ensure the normal operation of the equipment. At the same time, check if the thermocouple connections are correct to ensure the accuracy of temperature measurement.

3. Preparation of paper tube and filter paper:Produce a diameter of2.5-3mm、 A paper tube with a height of about 60mm is used to insert into the coal cup to prevent coal samples from entering the thermocouple iron tube. Prepare filter paper strips with a width of about 60mm and a length of 190-200mm to surround the inner wall of the coal cup and prevent the overflow of the gum.

three

Measurement steps of glial layer index

1. Sample preparation:Prepare coal samples with particle sizes smaller thanA 1.5mm air dried sample is crushed step by step using a roller crusher, ensuring consistent particle size composition. The time from sample preparation to testing of coal samples shall not exceed half a month to avoid oxidation of coal samples affecting the measurement results.

2. Sample installation:Load the coal sample into a specially designed coal cup, paying attention to the four part method of stacking the coal sampleAfter 25g, it should be flattened with a metal needle, but not compacted. After the sample is installed, it is necessary to lay asbestos pads and filter paper, and place them in a pressure plate for fixation.

3. Heating and recording:Strictly control the heating rate to ensure thatBefore 250 ℃, the rate was 8 ℃/min, and it was raised to 250 ℃ within 30 minutes; After 250 ℃, the rate is 3 ℃/min. During the period of 350-600 ℃, the difference between the actual temperature and the expected temperature should not exceed 5 ℃, and the rest of the time should not exceed 10 ℃, otherwise the test is invalid. During the heating process, attention should be paid to observing the changes in the coal sample and the overflow of the gelatinous body.

4. Measurement and recording:When the temperature reachesAt 250 ℃, start recording the volume curve. After the volume curve starts to decrease for a few minutes, the measurement of the glial layer layer layer begins and stops when the temperature rises to about 650 ℃. Measure the distance from the upper and lower layers of the glial layer to the bottom of the cup using a probe to obtain the glial layer thickness value (Y). Pay attention to the force and frequency during measurement, and avoid bringing out the glial body or affecting the position of the layer.

four

Precautions for measuring glial layer index

1. Coal sample processing:

During the placement of coal samples, oxidation and metamorphism should be avoided, otherwise it will affect the stability of the gelatinous layer index.

The prepared sample should be stored in a ground glass bottle in a cool and dry place, and should not exceed15 days.

2. Temperature control system:

Thermocouples must be effectively calibrated and accompanied by a temperature calibration table to facilitate timely self calibration by testing personnel.

The heating element should generate heat evenly to avoid uneven isothermal surfaces.

3. Coal cup and furnace brick:

The thermal conductivity of the coal cup will affect the test results, and the standard specifies its uniform use45 # steel.

The material of the furnace brick has a significant impact on the determination results of the resin layer, and furnace bricks with good heat dissipation, consistent or similar thermal properties should be used.

4. Measurement point specifications for different types of coal:

Select different points for probe measurement based on the direction of the glial layer volume curve.

Adopt corresponding measurement techniques and frequencies for different types of curves, such as smooth descent, zigzag, waveform, etc.

In summary, the measurement techniques for the gelatinous layer index of bituminous coal involve multiple aspects. Only by strictly following the operating procedures and standard terms can the scientificity and accuracy of experimental data be improved.

The measurement accuracy of the bituminous coal gelatinous layer index tester is high

Measurement and control of glial layerThe thermometer is an intelligent control instrument

Technical Indicators:

(1) It can control the heating process of dual furnaces or separately control the front and rear furnaces.

(2) The load power is not more than 5KW, and the thermocouple for temperature measurement is K-type.

（3　measurewarmRange: 000-999 ℃, resolution 1 ℃

measuretimeRange: 000-999min, resolution of 1 minute.

measureTime error± 30 seconds/24 hours. measurewarmAccuracy: ± 2 ℃

(4) Power supply voltage: AC 220 (1 ± 10%) V, 50 HZ

(5) Can work continuously.

Instrument Features

1. It has good temperature tracking characteristics, especially for large zigzag coal types, which can better reflect its properties.

2. Yes, there isstrongThe anti-interference ability, including the ability to restore power after power loss and silently restore the test time before power loss，Request operating parameters such as temperature and conduction angle.

3. Integration of instruments. The accuracy and safety reliability of software testing have been further improved.