Burden Bins - Ленгипромез

Main menu:

Burden Bins

PROGECTS

The burden bins of BF № 7 at “NLMK” OJSC represent a double-row structure consisting of twenty one burden material discharge channels.

The batches of burden materials after their discharge from the weigh hoppers are placed on a conveyer in the predetermined by the operating personnel sequence at the intervals depending on the furnace charging rate.

The burden material transfer from the burden bins to the blast furnace charging equipment is being performed by the main conveyer having the following specifications: the rated conveying capacity by weight – 1833 t/h, belt velocity – 2 m/s, belt width – 2000 mm, belt angle of inclination towards the horizon - 10˚30’00’’, material lifting height – 68.3 m, horizontal length – 493.5 m.

One of the burden bins distinctive features is the availability of a fines screening section. The fine fraction of sinter, pellets, coke from the burden bins building is reloaded from the longitudinal conveyers onto three cross conveyers and delivered to the fines screening plant. The fines delivered from the conveyers into the runs of the multi-run chute are distributed by means of a system of swinging gates onto the breeze-sizing screens and sinter/pellets fines screens. On the coke screen the small-sized coke is screened into the fractions of 10-35 mm (coke nuts) and of 0-10 mm. On the iron-ore materials screen the sinter/pellet fines are screened into fractions of 4-8 mm and 0-4 mm. Upon screening each fraction of coke and sinter/pellets is delivered into the corresponding bins and then into the railway cars.

Another one distinctive feature of the newly constructed burden bins is the availability of the sampling and sample preparation section intended for the on-line testing of the physical and chemical as well as of the metallurgical and mechanical properties of the burden materials to-be-delivered into the bins proper and charged into the blast furnace.

The test sample preparation system consists of three sections:

burden grain composition determination section comprising two lines for sinter testing, one line for pellets testing and one line for coke testing;
sample preparation section for the subsequent chemical analysis of the iron-ore materials comprising two lines for sinter and one line for pellets;
strength testing section for the iron-ore materials consisting of one line.

The representativity of the total (summed-up) sample of the burden materials for any testing is ensured by the intermittent taking of individual samples. The samples are taken upon screening from the materials flow at the moment of the weigh hoppers charging, gathered in the collecting bins forming in this way the total representative sample which is then transferred to the sample preparation section by means of two belt conveyers.

Return