Continuous sampling, detection and sample returning device of on-line ash tester

Abstract

The invention relates to the field of continuous sampling, detection and sample returning of an online ash meter for a coal preparation plant, and discloses a continuous sampling, detection and sample returning device of an online ash meter. The device is composed of a chute, a sampling port, an upper screw conveyer, an upper screw conveying channel, a lower screw conveying channel, a wear-resistant polyethylene measuring tube, a radioactive isotope online ash content meter, a lower screw conveyer, a return baffle and the like. Coal flow enters the upper spiral conveyor through the sampling port and is conveyed to the discharging end of the upper spiral conveyor, the coal flow falls into the lower spiral conveyor under the gravity action of a coal flow coal sample and is conveyed into the wear-resistant polyethylene measuring pipe, and a detector and a radioactive source of the ash content meter are located at the upper end and the lower end of the wear-resistant polyethylene measuring pipe respectively, and the measured coal flow returns to the chute through the chute discharge hole and the return baffle. The device can eliminate the influence of external factors such as steel wires in the adhesive tape, the compaction degree and the thickness of a coal seam and the like on ash content measurement, and can remarkably improve the measurement precision and the accuracy of an online ash meter.

Description

technical field [0001] The invention relates to the field of continuous sampling-detection-sample return of an online ash meter used in a coal preparation plant, in particular to a continuous sampling-detection-sample return device for an online ash meter. Background technique [0002] In the coal preparation industry, whether it is a thermal coal preparation plant or a coking coal preparation plant, the most important product is clean coal, and the most important quality index of clean coal products is the ash content of clean coal products. The quality of coal products is high or low, so the real-time detection of ash content of clean coal products is very important in the daily production of coal preparation plants. The main technology and method for clean coal ash detection is the radioisotope online ash analyzer, that is, the radioisotope online ash analyzer is installed on the clean coal belt, and two sets of gamma rays with different energies are released according to...

AI Technical Summary

Problems solved by technology

[0003] In fact, there are many factors that affect the measurement accuracy and accuracy of the radioisotope online gray meter during use. Since the current radioisotope online gray meter is installed on the belt, the belt of the belt conveyor is generally embedded with steel wires. It is used to enhance the tensile strength of the tape. The steel wire has a high density and a large absorption coefficient for rays. However, the steel wire is not uniformly and continuously distributed along the cross-section of the tape. The detection has a great influence; the clean coal enters the belt conveyor after being dehydrated by the previous centrifugal dehydrator, and its accumulation pattern on the belt conveyor belt is irregular, the thickness of the coal seam is uneven, and the attenuation intensity of the ray passes through coal seams of different thicknesses. The detection of ash content is inaccurate; due to the irregular and uneven accumulation of coal flow on the belt conveyor belt, the compaction degree of coal flow on the belt is not the same everywhere, and in some places the coal seam is compacted and the porosity is small. The absorption of radiation is relatively large, and in some places the coal seam is relatively loose, the porosity is large, and the absorption of radiation is small, which will also cause the measured ash content of clean coal to be different

Therefore, there are many external factors affecting the measurement precision and accuracy of the radioisotope online gray meter, and the influence is relatively large.

With the continuous advancement of the national overcapacity reduction policy and fewer new coal preparation plants, in order to achieve efficient and full utilization of resources, the state vigorously advocates and increases the washing rate of raw coal. Because the past coal preparation plants did not consider intelligent control when designing The rapid development of the coal preparation industry has resulted in the inability of many existing coal preparation plants to install radioisotope on-line ash meters on the clean coal belt, or the lack of space in the workshop of the coal preparation plant; and through the above analysis, the installed on the clean coal belt There are many external factors in the detection of clean coal ash by radioisotope on-line ash analyzer

Images