SU1481253A1 - Method of processing coal-cleaning waste - Google Patents

Abstract

The invention relates to the coal industry, in particular, to the processing of coal waste in suitable for transportation and storage of briquettes, which can be used for the production of ceramics and aggregates of concrete, as well as for burning in boilers. In addition, the briquetting of coal enrichment waste will simplify the solution of the problem of waste-free technology of coal factories and environmental protection. The goal is to simplify and cheapen the processing of coal waste. The suspension of coal enrichment waste is thickened with a fraction of up to 0.1 mm of 70-90 wt.% And ash content of 60-80% in a thickened suspension. - 40 MPa for 10 - 20 s. 1 hp ff, 3 tab.

Description

i

The invention relates to the coal industry, in particular to the processing of coal waste into suitable for transportation and storage of briquettes that can be used for the production of ceramics and aggregates of concrete, as well as for burning in fluidized bed furnaces, which allows to simplify the solution of waste-free coal mining and environmental technology.

The purpose of the invention is to simplify and cheapen the processing of coal waste.

Primer p. The waste is processed at the beneficiation plant of the coal preparation plant. Float waste with ash content of 57.1%, size of 0.5 - 0 mm thickens on a bench hydrocyclone to 540 g / l (viscosity 3530 P). The thickened suspension contains 82% by weight of a fraction of 0.1-0 mm with an ash content of 71%. The moisture content of the flotation waste is 42%, the carbon content is 22.88%, the heating value is 2120 kcal / kg.

The chemical composition of the ash part of the flotation waste,%: SiOj 55.35; CaO 4.24; 1-tgO 1.79; HeG03 7.38; A1A03 26.10; T10 g 0.75; K20 3.10; Ma20 0.65; S03 1.33; other 0.18. Mineral-petrographic composition,%: hereditary substance 14; fusenized substance 3; pyrite 4; clay 64; quartz 10; calcite 1; siderite 1.

J

00

Yu

SP

WITH

314

Waste jigging - waste after the enrichment of coal of the class of 0.5–13 mm with ash content of 30.4%, grade G. Humidity waste jigging 12.66%.

The chemical composition of the ash part of the jigging waste,%: Si07 47.43; CaO 2.50; MgO 2.05; Fea03 20.84; Ala03 19.30; I0g 0.64; 2.70; NatO 0.60; S03 2.18; other 1.76. Mineralogical composition of waste jigging,%: organic matter 18; mineral impurities: quartz 10, calcium 1, pyrite 11, clay 58, and others 2. The carbon content in the jigging waste is 9.86%, the heating value is 833.16 kcal / kg.

Condensed flotation waste is mixed with jigging waste of 0-6 mm fraction with ash content of 82.4% in a mass ratio (%) of flotation waste to jigging waste of 25:75, as a result of which the moisture content of the mixture is 20%. A mixture with a temperature of 21 ° C is loaded into the cells of a laboratory hydraulic press and cylindrical briquettes are pressed at 30 MPa for 15 s (diameter 16 mm and height 20 mm) with a moisture content of 6.1% and strength of 19.7 kg / briquette (4.6 kg / cm) During pressing, the mixture is dehydrated due to the removal of moisture through the matrix – punch gap, which accumulates on the die tray. The density of the obtained briquettes 2.2 - 2.4 kg / cm3. The productivity of the process in the laboratory is 20-25 briquettes / hour.

For comparison with a known method, the same mixture is molded by extrusion, followed by drying the granules at 90 ° C for 3 hours in a monolayer, resulting in a moisture content of the granules of 7.1%, strength 1.5 kg / / granule.

In tab. Figures 1 and 2 show the values of moisture content and strength of briquettes when the pressure and pressing time are changed, respectively, within the proposed limits and when they deviate from them (d M is the maximum size of the jigging waste; the content in the flotation waste mixture; v0 is the content in the jigging waste mixture; concentration of solid flotation waste in suspension; Toi fraction content up to 0.1 mm in flotation waste; A 01 - ash content of fraction up to 0.1 mm, P - pressure 0

0

five

compaction, t is compaction time).

As can be seen from the data table. 1, when the pressing pressure is less than 20 MPa, the humidity of the briquettes increases significantly, and at pressures of more than 40 MPa it stabilizes at the level of 5.8%, therefore the most rational limit of the pressing pressure is 20-40 MPa.

Data analysis table. 2 shows that the moisture content of the pressed product substantially depends on the pressing time. Moreover, to obtain satisfactory results that are almost identical to the known method (with drying), it is sufficient to set the pressing time to more than 10 s. It is impractical to carry out the pressing process for more than 20 s due to the stabilization of the humidity of the briquettes. Therefore, the required pressing time is 10–20 s. During this time, the moisture content of the pressurized waste decreases to 7.8-5.6%. The strength of the briquettes weakly depends on the pressing time (to a lesser extent than the pressing pressure and the binder composition — fine waste fractions).

In tab. 3 shows the strength values of briquettes spoiled by the proposed method, depending on the content in the flotation waste of up to 0.1 mm and their ash content.

0

0

Data analysis table. 3 shows that the strength of briquettes at fo is 90-70%, A0i 60-80% is in the range of 17.1-24 kg / briquette. This practically minimizes the splitting of briquettes during transportation, shipping, etc. operations. When the mind is less than 70% and A 0.1 less than 60% other

5 The capacity of briquettes drops sharply. When y0 is more than 90% and A 0 | 1 is more than 80%, the strength of the briquettes is stabilized. This determines the feasibility of limits in 0.1–90–70% and Aoi 60–80%.

The proposed method, in contrast to the known, allows one to perform dewatering and shaping of enrichment waste with less than the known number of operations and with less waste (by eliminating the heat-drying operation), processing costs are reduced by 4.5 times, which reduces the cost recycling, accelerates recycling

0

and creates prerequisites for increased productivity.

table 2

Claims (1)

1. A method for processing coal enrichment waste, including thickening a suspension of fine fractions of coal enrichment waste, mixing it with dry coal enrichment waste of less than 10 mm, shaping and dewatering the waste mixture, characterized in that, in order to simplify and reduce the cost of processing, the briquette is formed and dehydration is carried out by pressing the mixture of waste at 20-40 MPa for 10-20 s. 2, Method Pop.1, characterized in that a thickened slurry is used with fractions up to 0.1 mm of coal wastes 70-90% by weight and ash-content 60-80%. Table 1 dw 6 mm 3V 25% 512,718,2 Guo% U7,819,0 C 540 g / l 156.119.7 6M 82% 15 Ta b faces 3 20 25