Glass and Ceramics Vol. 53, Nos. 5 - 6, 1996

AT THE ENTERPRISES AND INSTITUTES

UDC 666.122.2:622.75/.77

A E R O D Y N A M I C C O N C E N T R A T I O N O F Q U A R T Z S A N D

A. K. Brovtsyn I and G. S. Chershneva ~

Translated from Steklo i Keramika, No. 6, pp. 28 - 29, June, 1996.

A fundamentally new multipurpose installation for aerodynamic concentration of quartz sand and similar friable materials is described. The installation ensures the production of high-qualiD: molding and glass sands.

The growing demand of casting production, glass plants, and other industries in Russia for high-quality and inexpen- sive quartz raw materials is not satisfied completely due to the exhaustion of some deposits. Therefore, a search for new sources of quartz raw materials and the development of highly efficient technologies for concentrating quartz sands have great practical value [ 1, 2].

The Mikhailov Mining and Concentration Plant (MGOK) is a modern well-equipped enterprise with a reliable raw-ma- terials base and a high level of integration of science and technology. MGOK produces agglomerated ore, iron ore con- centrate, and iron ore pellets.

In order to utilize the strip layers o f the Mikhailov De- posit (iron quarxzites) MGOK is carrTing out work on con- centration of quarXz sand by a wet method on the basis of hy-

Obninsk Institute of Nuclear Power; Tekhnologiya Obninsk Research and Production Association, Obninsk, Russia.

90

80

70

~j 60

40

30 L)

20

10

/ ' /

/ / 005 01 02 04 0.63 1.0 d mm

Fig. 1. Integral curve of the size distribution of quartz sand particles: 1 ) in- itial quartz sand (sample 2); 2 ) concentrated quartz sand from the same sam- ple that is prepared by the aerodynamic technolog7.

TABLE 1

Sample 1" Sample 2""

Screen initial sand in dynamic chamber under short- number duration regime

initial sand

residue on the passed through residue on the passed through residue on the passed through screen, % the screen, % screen, % the screen, % screen, % the screen, %

in dynamic chamber under Iong- duration regime

residue on the passed through screen % the screen, %

063 6.6 93.4 5.4 94.6 5.3 94.7 5.6 94.4

05 87 84.7 8.9 857 90 857 10.7 83.7

04 17.2 67.5 15 0 70.7 16.6 69.1 17.8 65 9

0315 23.2 44.3 21 7 49.0 21.1 48.0 20.5 45 4

02 37.3 7.0 38.1 10.9 39.6 8.4 40.4 5.0

016 5.2 1.8 6.3 46 5.6 2.8 3.9 lA

01 1.5 0.3 2,8 1.8 2.2 06 08 03

005 04 0 1.3 0.5 0,5 0.1 0,3 0

Trab 0~1 - 0.2 03 0.1 0 0 -

.~Sand residue in the cyclone is 29%, and in the filter 0.5%. Sand residue in the cyclone is 28,5%, and in the filter 0,6%.

188 0361-7610/96/0506-0188515.00 © 1997 Plenum Publishing Corporation

Aerodynamic Concentrat ion o f Quartz Sand 189

t, min

Fig. 2. Extractability Q of quartz sand particles as a function of the duration t of the process of aerodynamic concentration.

TABLE 2

Sand in the concentration regime Initial sand Parameter

(08 mm) short-duration Iong-duration (sample l) (sample 2)

Mean diameter, mm 0.34 0.315 0.33 Coefficient of homogeneity, % 60.5 63.5 67.0 Residue on screen No. 0.2, % 94A 89.1 95.0

TABLE 3

Mass fraction of harmful impurities, %

corresponds to Corresponds to Specimen Na20, CaO, the group of Fe203 the groupof AI203

K20, MgO GOST 2138-91 GOST 2138-91

Initial sand 0.53 Iow 1,30 ver 5, high 0.58 Samplel 0,24 verylow 0.42 indurationediate 029 Sample 2 0.24 the same 0 19 ver3' low 0~ 19

droclassification with the aim of fabricating a quartz raw ma-

terial for casting and glass productions. In 1995 the Obninsk Institute ofNuclear Power in coop-

eration with the Tekhnologiya Obninsk Research and Produc-

tion Association together with MGOK specialists conducted

an investigation on aerodynamic concentration of quartz

sands from strip layers of the Mikhailov Deposit.

The investigation was based on modeling the technologi-

cal processes by using physical models and similarity theory

in conducting experiments and processing their results.

TABLE 4

Corresponds to the group Specimen Mass fraction of silica, % of GOST 2138-91

Initial sand 978 K 3 Sample 1 99.2 Kj Sample 2 99.5 K I

TABLE 5

Clay Corresponds to the Corresponds to the Specimen component, group of GOST pH" group of GOST

% 2138--91 2138-91

lnitial sand 1.05 4 3.55 acid Sample 1 0.78 3 5.39 the same Sample 2 0.32 2 6.63 neutral

"Concentration of hydrogen ions in the withdrawn watet.

The experimental study of the initial and the concentrated quartz sands was conducted in accordance with the require- ments of GOST 2138-91 and GOST 22551-71. Some of the results are presented in Tables 1 - 5 and Figs. 1 and 2. 2

The results of the investigation became the basis for tech- nological specifications for the design of a fundamentally new (Russia Patents 2001705, 2008982, 2010624, 2010625, 2010626, and 2030929)multipurpose installation for aerody- namic cõncentration of quartz sands and similar friable mate- rials, which envisages the production of molding sands of a ve~, high qualle' and glass sands of grade B-100-1 and

higher.

At the present time the plant is working on the creat ionof an experimental industrial installation for dynamic concentra-

tion of quartz sand.

R E F E R E N C E S

1. ~ü. R Lezhnev, "Current trends in the development of the technology for concentrating glass sands," Steklo Keram., No. 11, 9 - 11 (1979).

2. A. K. Brovtsyn, V. I. Sergeechev, and G. S. Chershneva, ùAeroelectrodynamic concentration of quartz sand," Steklo Keram., No, 3 - 4, 28 - 30 (1994).

The experiments were conducted with the participation of P M Mais- trenko, E. D. Seregina, K. B, Shamshetdinov, and "u~ N, Kazantsev of the Tekhnologiya Association,