GB/T 3332-1982 Determination of beating degree of pulp (Schauber-Rieger method)
Some standard content:
National Standard of the People's Republic of China
Determination of beating degree for pulps(Schopper-Riegler method)
UDC 676.11/.19
GB 3332-82
Beating degree is an indicator to measure the performance of pulp suspension in water. This standard is expressed in terms of Schopper-Riegler (SR) degree value. 1 Instrument
The beating degree should be determined on a beating degree measuring instrument that meets the following requirements. 1.1 The structure of the beating degree measuring instrument is shown in Figure 1. Issued by the National Bureau of Standards on December 29, 1982
Implemented on August 1, 1983
GB333282bZxz.net
Electric 137
Figure 1 Schober Instrument
1-Water filter cylinder, 2-conical cover, 3-copper mesh, 4-separation chamber, 4
5-umbrella frame, 6-bottom hole, 7-side flow tube1.1.1 The water filter cylinder is a cylinder with an inner diameter of 137mm. The bottom end of the inner wall of the cylinder is a 45-conical surface, and it is connected to a cylinder with an inner diameter of 112.9±0.1mm (cross-sectional area of 100cm2). The copper mesh is tightly fixed in the circular cylinder 25mm below the cone surface, and the mesh surface is flat. It is perpendicular to the center line of the cylinder. The copper mesh should meet the 80-mesh standard specified in QB326-62 "Single-woven copper mesh for papermaking". 1.1.2 The cone cover (see Figure 2) has an outer diameter of 120 mm, and the cone is 55° to the vertical line. The cone cover is fixed on a vertical shaft with an outer diameter of 20 mm. A 10 mm diameter ventilation hole is connected between the cone cover and the center of the hollow shaft to allow air to pass through when the cone cover is lifted. A rubber gasket with a Shore hardness of 30° is embedded in the support surface of the cone cover as a sealing ring. The cone cover should be lifted at a constant rate of 100±10mm/s. 362
GB3332—82
Figure 2 Conical cover
1.1.3 The separation chamber (see Figure 1) is a cylinder with a height of 35 mm, and there is a vent hole on the side of the cylinder to balance the air pressure. There are three grooves on the inner wall to fix the position of the umbrella frame. The lower part of the separation chamber is a conical part with a cone angle of 40°. The diameter of the bottom hole at the tip of the cone (see Figure 3) should be sufficient to allow 1000 ml of water (temperature 20±0.5°C) to be completely discharged within 149±1s when poured into the separation chamber. The hole diameter is about 2.32 mm. A side flow tube is inserted into the side wall of the conical part, which is 49° to the center axis of the separation chamber. The upper end of the side flow tube is inclined at 12° to the center axis of the separation chamber, and the overflow edge is as close to the center axis of the separation chamber as possible. The volume between the bottom hole and the overflow edge at this position should be between 7.5 and 8.0 ml. The horizontal plane of the overflow edge should be adjustable. A movable umbrella frame (see Figure 4) is stored in the separation chamber to prevent water from splashing into the side hole. One of the supporting legs of the umbrella frame should be placed radially with the side flow tube. 18
Figure 3 Bottom hole
GB 3332—82
Figure 4 Umbrella frame
1.1.4 Measuring cylinder. The scale on the measuring cylinder should enable the Schober's (SR) value to be read directly, so that a volume of 1000ml is equivalent to zero degrees of SR value, and a volume of 0ml is equivalent to 100 degrees of SR value. The distance between the two scales equivalent to a volume of 10ml (i.e. 1 degree of SR value) is at least 1.5mm.
2 Calibration of the beating degree measuring instrument
2.1 Adjust the position of the instrument so that the copper mesh remains horizontal. 2.2 Pour water into the filter cylinder to check whether the sealing cone cover is leaking. In good condition, there should be no leakage. 2.3 Cleanliness of the instrument:
There should be no fiber or other sediment in the instrument. If necessary, it can be cleaned with detergent and rinsed thoroughly with clean water. The cleanliness of the copper mesh can be tested by blank test with distilled water according to the method described in the operation steps and results of Article 4. If the test result exceeds 4SR, it means that the copper mesh must be cleaned. It can also be scrubbed with acetone and a soft brush, and rinsed with clean water. If the copper mesh is unqualified, it should be replaced. 2.4 Position of the side flow tube:
Block the bottom hole with your finger, pour 100ml of distilled water at 20±0.5℃ into the separation chamber, and after the excess water has completely flowed out of the side flow tube, release the bottom hole and collect the water flowing out of the separation chamber. The volume of this water should be between 7.5 and 8.0ml, otherwise the position of the side flow tube should be corrected.
2.5, Check the size of the bottom hole:
GB 3332-—82
Take out the umbrella frame, plug the side flow tube hole with a plug, plug the bottom hole with a finger, pour 500ml of 20±0.5℃ distilled water into the separation chamber, and after a while, open the bottom hole to let the water flow out. Plug the bottom hole again, pour 1000±5ml of 20±0.5℃ distilled water into the separation chamber, and record the drainage time of the bottom hole, which should be 149±1s. If the time is too long, use appropriate tools to enlarge the hole. If the time is too short, replace the bottom hole.
2.6 Check the lifting rate of the conical cover. This rate should be maintained at 100±10mm/sc3 Sample preparation
3.1 The samples are all taken from the dissociated slurry water suspension. If the concentration of the slurry is not known exactly, it can be diluted with distilled water or ion exchange water to a concentration of about 0.22%, and its concentration can be determined according to the method specified in Appendix A. Then it is diluted to a concentration of 0.198~0.202%, and the temperature is adjusted to 20±1℃. During the sample preparation process, avoid the formation of bubbles in the suspension. 4 Operation steps and results
4.1 Thoroughly clean the separation chamber and the filter cartridge. Place the filter cartridge on the separation chamber, put the conical cover in the closed position, pour 20±1℃ distilled water or ion exchange water into the filter cartridge to adjust the instrument temperature, lift the conical cover to drain the water, and place the SR measuring cylinder under the side flow tube. 4.2 Take 1000±5ml of the prepared slurry suspension in a measuring cylinder, stir it evenly and immediately pour it into the filter cylinder. After five seconds, lift the conical cover, and the filtered water passing through the copper mesh will be discharged from the bottom hole and the side flow tube through the separation chamber. When the side flow tube stops dripping, read the SR value, which is the result of the measurement.
Each slurry should be measured twice, and the arithmetic mean value shall be taken as the measurement result, but the relative error between the two measured values shall not exceed 4%.
GB 3332—82
Appendix A
Determination of slurry concentration
(Supplement)
Slurry concentration refers to the percentage of the absolute dry slurry weight of the slurry sample to the weight of the slurry sample. A.1 Instruments
Measuring cylinder 500mlg
Balance: a balance with a capacity of not less than 500g and a sensitivity of 0.5g or a balance with a capacity of not less than 100g and a sensitivity of 0.01g. b.
Weighing bottle.
d. Dryer.
e. Infrared fast dryer or oven, with a temperature control range of 105~150℃. Buchner funnel with a diameter of 90~150mm.
A.2 Sample preparation
A.2.1 The sample should be collected quickly when the slurry is fully stirred. The sample quantity can be collected at one time or in several small amounts.
A.2.2 If the slurry concentration is lower than 0.3%, the slurry weight should be sufficient to ensure that the absolute dry weight is 1~5g. A.2.3
When the slurry concentration is between 0.3% and 1%, take about 500g of the sample, pour it into a weighed container, and weigh the net weight of the slurry with a balance.
A.2.4When the slurry concentration exceeds 1%, take about 100g of the sample, pour it into a weighed container, and weigh the net weight of the slurry with a balance.
A.3 Determination steps and calculation of results
A.3.1 Weigh the constant weight of the weighing bottle and filter paper:
Put the filter paper with the same size as the funnel and suitable for the sample to be filtered into the weighing bottle, place it in an infrared quick dryer or oven, dry it in the temperature range of 105-150℃, move it into the dryer, cool it, and weigh it with a balance with an accuracy of 0.01g. Repeat the above operation. When the difference between two consecutive weighings is no more than 0.01g, it is the constant weight of the weighing bottle and filter paper. A.3.2 Filtration and constant weight of the sample:
Place the Büchner funnel with constant weight filter paper on a 1000ml glass suction filter bottle and moisten it with distilled water. Filter the slurry sample in the container and rinse the inner wall of the container with a small amount of water. The washing liquid should be poured into the funnel for filtration. To ensure that the filtrate does not contain any suspended matter, if there is precipitation, it should be poured into the funnel again. If necessary, the test can be repeated with a tighter filter paper. Carefully remove the filter paper and fiber layer from the funnel and put them in a weighing bottle. In the same way as A.3.1, dry the weighing bottle, filter paper and fiber layer together to constant weight. A.3.3 Pulp concentration X (%) is calculated according to the following formula: X=%=b×100
W-net weight of slurry, g.
Take the arithmetic mean of two determinations as the result of the determination, and take the determination value to the second decimal place. 366
Additional remarks:
GB3332—82
This standard was proposed by the Ministry of Light Industry of the People's Republic of China. This standard was drafted by the Paper Industry Science Research Institute of the Ministry of Light Industry. The main drafter of this standard is Zheng Shuxiu.
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