SU1629565A1 - Composition for wetting of coal dust - Google Patents

Abstract

The invention relates to the mining industry and can be used to obtain aqueous solutions of a wetting liquid. The purpose of the invention is to ensure the safety of the performance of the composition during long-term storage. For this, the composition contains the following ingredients in a ratio, wt.%: Diethenolamides of synthetic fatty acids of CJQ С fraction, 20-25, calcium chloride 30-35, sodium chloride 25-30, water - the rest. The incorporation of sodium chloride into the coal dust wetting composition allows the wetting composition to remain in a solid, patronized form for a long time (up to two months). 4 tab. (L

Description

The invention relates to the mining industry and can be used to obtain aqueous solutions of a wetting fluid used in the irrigation technique for unloading and transporting coal, as well as for injecting into coal seams in order to reduce dust formation during coal extraction.

The aim of the invention is to ensure the safety of the performance of the composition during long-term storage.

The composition contains ingredients in the following ratios, wt.%: I

Diethanolamides synthetic fatty acids fraction Xu C4E

Calcium Chloride Sodium Chloride Water

20-25

30-35

25-30

Rest

S & U

WITH

sd

about ate

Due to the fact that sodium chloride crystals in the cartridge are evenly distributed among the surfactant molecules and calcium chloride crystalline hydrates, it is difficult to directly diffuse water vapor from the air into the inner layers of the cartridge. This allows the cartridge to retain its properties and durability.

This greatly simplifies the storage and transportation of solid wetting agent and ultimately improves the technology of its application.

The content of sodium chloride in the composition in the range of 25-30 wt.% And calcium chloride in the range of 30-35 wt.% Is due to the conditions for giving the samples a solid consistency and the need to maintain optimal wetting properties (i.e. maximum wetting speed).

A decrease in the electrolyte content in the composition of less than 30 wt.% (For calcium chloride) and less than 25 wt.% (For sodium chloride) leads to a loss of hardness of the composition, and an increase of more than 35 wt.% And 30 wt.%, Respectively, leads to a deterioration in wetting. properties. In addition, the content of sodium chloride less than 25 wt.% Leads to a more rapid spreading of the cartridge in the air and loss of operational properties.

The content of DEA in the composition in the range of 20-25 wt.% Is due to the high wetting properties, which depend on the ratio DEA / / (CaCl + NaCl). The latter should exceed 1/4. In addition, an increase in the DEA content of more than 25 wt.% Is not advisable, since this leads to a loss of the hardness of the composition, while a decrease of less than 20 wt.% Reduces the wetting rate of the coal dust.

A composition intended to be further dissolved with water when used or when it is injected into a coal seam or when irrigating dust sources is prepared as follows (Table 1). A composition containing DEA 25 wt.%, CaC12 35 wt.%, NaCl 30 wt.% And water 20 wt.% Is prepared in a mixer, to which is mixed with added calcium chloride (30 g) and water (20 ml) before the formation of a pasty salt gruel, 25 g of DEA are added at the same time with constant stirring, then 30 g of NaCl are added thereto. After a short mixing, the mixture is formed in the form of a cartridge-cylinder of the following dimensions: diameter 3-4 cm; length 30-40 cm. Upon contact with air (within 3-4 hours), the cartridge acquires strength and stable shape.

0

five

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With further use, the cartridge is placed in a perforated cartridge holder connected to the water supply system. For practical use it is diluted to a concentration of 0.05-0.20 wt.% Based on DEA.

In tab. 3 and 2 are examples showing the effectiveness of wetting fine anthracite dust (fraction less than 70 microns) by the film flotation method for the known and proposed compositions. From a comparison of the data table. 3 and 2, it follows that with the same DEA concentration (within 0.05-0.20 wt.%) The use of a mixture of electrolytes (CaCl2 and NaCl) does not impair wetting as compared with the known composition (based on CaCl2).

Table 1

DEA 20

DEA 20

The order of mixing is similar to the order of mixing for the composition indicated in the text. In tab. Table 4 gives the results of studying the duration of the preservation of the strength and shape of the cartridge of the known and proposed composition at 20 ° C and an air humidity of 60-70%. The cartridge, 3–4 hours after preparation, is left in the vertical state for a long time, with both external signs of spreading (wet surface) and changes in geometric dimensions. It follows from the data that the proposed formulations are kept 5-10 times longer while maintaining effective wetting of the dust.

Due to these factors, the use of the proposed composition will improve the sanitary and hygienic working conditions of workers associated with the extraction and processing of coal.

Claims (1)

Composition for wetting coal dust / l, including diethanolamides of synthetic fatty acids of fraction C _<о -С ₁₃ , calcium chloride and water, characterized in that, in order to ensure the safety of performance during long-term storage, it additionally contains sodium chloride with the following components , wt.%: Diethanolamides of synthetic fatty acids fraction C _<0 -C <s Calcium Chloride Sodium Chloride Water ratios 20-25 30-35 25-30 Rest