RU1795119C - Method for determination of outburst hazard of coal seam - Google Patents

Abstract

The invention can be used to determine the structural disturbance of coal and, as a consequence, the outburst hazard of a coal seam. The method allows to simplify the determination of the outburst hazard of the formation by physicochemical methods. The coal sample is ground, filled with distilled water and stirred for 4-5 minutes. The carbon solution is then transferred to the filter. The time of occurrence of the first drop of filtrate and the time when flowing are recorded. For 1-2 minutes, drops are not observed. The filtration time is determined. If it is 10 minutes or more, the formation is considered to be outburst hazardous; if it is less than 10 minutes, the formation is coal, from which a sample is taken that is not outburst hazardous.

Description

(L

WITH

. The invention relates to the mining industry and can be used to determine the structural disturbance of coal in order to increase the safety of mining operations.

A known method for determining the disturbance of coal by the amount of iodine absorbed by a portion of coal.

According to this method, the test sample of coal is crushed to a particle size of 0.35-0.50 mm. One gram of the sample is placed in a conical flask and filled with 100 ml of iodine solution. After stirring for five minutes on the shaker, the charcoal is filtered off. 20 ml of the filtrate was transferred to a 100 ml conical flask, 2-3 drops of starch were added and titrated until the blue color disappeared. Calculation of D | produced from the ratio:

D | .- (a-b) xO. 635,

where a is the amount of titrated solution of thiosulfate (Naa ZaOz):

b is the amount of thiosulfonate solution consumed in titration of iodine not absorbed by coal;

0.635 - conversion factor.

If DI 3,5, then the reservoir is hazardous.

The main disadvantage of the described method is that it cannot be used in a mine due to the complexity of the equipment. In addition, the iodine solution should be freshly prepared, as iodine and its solution are very unstable compounds, and a change in its amount in the solution distorts the results.

A known method for determining the degree of disturbed ™ angle, and, as a result,

hazard for maximum water saturation of the latter (2).

The method consists in the fact that the samples of coal of two fractions are dried, and then placed in a desiccator, in which constant relative humidity (95-98%) created by a 10% solution of sulfuric acid is maintained. 24 hours, and a sample of coal fractions of 2.6-Z. mm can withstand 60-90 minutes After stabilization of the weight, the change in sample weight is determined.

The known method is not used in mines, as it is laborious and not sufficiently operational. In addition, even in laboratory conditions, it is not always possible to accurately determine the initial humidity, because the loss of weight from degassing during heating is not taken into account.

Research conducted at the institute showed that an indicator such as the time of filtering a coal suspension through a paper filter can be used to determine the degree of disturbed formation ™.

The aim of the invention is to increase the efficiency of determining the coal seam emissions.

The goal is achieved in that in a method for determining the outburst hazard of a coal seam, including sampling, grinding and moistening with liquids, determining the outburst hazard of a seam, the sample is moistened by mixing with distilled water and filtered, while the occurrence of the first and last drops is recorded, and the time filtration is determined by the formula

Dt Tmax - That

where TO is the time of occurrence of the first drop;

Claims (1)

SUMMARY OF THE INVENTION A method for determining the outburst hazard of a coal seam, including sampling, grinding, wetting with liquids and classifying the seam as outburst hazard according to a selected criterion, characterized in that, in order to reduce the time of determining the outburst hazard and the possibility of use directly in the mine conditions without involving chemically harmful substances, the sample is moistened by mixing with Tmax is the time of occurrence of the last drop. and at Dt Yu, min, the coal seam is non-non-hazardous, and at Dt 10 min - outburst hazardous. As a result of the studies, it was found that when the coal sample was mixed from the hazardous zone with distilled water, an additional destruction of the taken fraction was observed, which was apparently associated with the physical effect of water on the weak structural elements of coal. Destructed elements slow down the separation of water-coal 5 suspension, which increases the filtration time and allows you to set the emissions of coal seams by this factor. The method is carried out as follows. A coal sample is ground and 2 grams of a 0.3 mm fraction is poured into 40-50 ml of distilled water and stirred for 4-5 minutes. Then transfer the solution with coal to 5 filter. The time of occurrence of the first drop of filtrate T0 and the time when no drops of Tmax are observed for 1-2 minutes are recorded. The filtration time is determined from the ratio Dt Tmax - That. If Dt is 10 minutes or more, then the coal seam from which the sample is taken is outlier hazardous. If Dm is less than 10 minutes, the formation is non-hazardous. The method has a number of advantages, including being more efficient in comparison with the prototype; no chemically harmful substances are used in its implementation; allows you to use 5 0 in mine. distilled water and filtered, while the occurrence of the first and last drops is fixed, and the filtration time is determined by the formula DT Tmax - That, where T0 is the time of occurrence of the first drop; Tmax - time of occurrence of the last drop, and at Dt 10 min the coal seam is classified as non-exhaustive, and at Dg 10 min it is classified as outburst hazardous.