SU440545A1 - Device for ventilation and dedusting of open electric arc furnaces - Google Patents

Description

one

The invention relates to metallurgy.

Apparatuses for ventilation and dedusting of open electric arc furnaces are known, including an umbrella installed above the collars and connected via a dust collector with a smoke exhauster.

The purpose of the invention is to reduce the amount of exhaust gases emitted into the atmosphere. For this, the proposed device is provided with an annular manifold with a slit directed inside the umbrella located at the furnace top under an umbrella along a perimeter, connected by a duct to a smoke exhauster mounted on a bubble-type hydrodynamic dust collector, the outlet of which is connected by a pipe to an inlet pipe of a continuous filter, outlet the filter nozzle through the pump is connected to the sprayer introduced into the upper part of the hydrodynamic demolver. Nozzles are attached to the bottom of the inlet nozzles of the dust collector connected to a common collector.

FIG. 1 shows the proposed device, a general view; in fig. 2 is a diagram of the interaction of flows of a gas-water mixture in the gaps between adjacent bowls and nozzles.

Above the furnace 1 is an umbrella 2 connected by a duct 3 with a hydrodynamic dust collector 4 of the bubble type, on which a smoke-free installation 5 is placed. A duct 6 is connected from the smoke exhaust installation connected to an annular manifold 7 located on the furnace top 1 under an umbrella 2 along its perimeter directed inside the umbrella. The outlet nozzle of the hydrodynamic dust separator 4 is connected by a pipeline to the inlet nozzle of the continuous filter 8, and the nozzle for draining the filtrate through the pump 9 is connected to nozzles 10 installed in the dust separator body 4. The bottom of the 11 collectors 11 of the dust separator united by a common collector are attached to the nozzle 13, provided with a profile hollow along the entire perimeter, around which cups 14 with openings in the lower part are coaxially aligned with them with a gap. The nozzles 13 and the cups 14 are rectangular in plan. The profile recess is made in the form of two conjugate radii RI and Rz, with the R upper recess less than the Rz lower recess. The size of the gap L between the cups 14 is equal in the longitudinal and transverse directions.

The device works as follows. The flue gases from the furnace 1 are sucked in by the umbrella 2, through the duct 3 they enter the hydrodynamic dust collector 4, where they are bubbled through the nozzles 13 and the bowls 14 into the water and cleaned: they come from dust. Then they enter the smoke-free installation B, are partially emitted into the atmosphere, and partly through the duct 6 are sent to the annular collector 7. The exit from the w, spruce of the collector at a speed of 20-25 m / s, the gases form a dense curtain, preventing air entering under umbrella 2. The gases are sucked in by the umbrella again and the cycle repeats.

The pulp formed in the dust collector enters the inlet of the continuous filter 8, on the tape of which the pitch remains, consisting of trapped dust released during smelting, and the filtrate is sucked in by the pump 9 and is injected into the nozzles 10. There the filtrate is sprayed and forms additional the veil promoting the best dust collection.

The dusty gas stream through the inlet nozzles 12 of the dust collector 4, which enters the body of the latter, hits the mirror of the poured water and the largest dust particles are trapped. The outflow of gases in each nozzle 13 is divided into four streams and, by ejecting water, flows into the gaps between the nozzles 13 and the bowls 14.

When the gaseous mixture leaves the gaps L between the plates and the nozzles, a counter-impact of the two flows is formed. Each stream contains particles with opposite charges. When a stream collides, positively charged particles from a single stream attract negatively charged particles from another stream and vice versa. From

collisions, particles are enlarged and are lowered along with the water contained in the streams. Small droplets of water, which were carried away by the gas flow upward, move along the generatrix of the upper recess with a radius Ri and are reflected for the second time, getting a downward direction. At the same time, fine fractions of dust are finally collected, and the purified gas is sucked off by a fan and thrown out.

Subject invention

A device for ventilation and dedusting of open electric arc furnaces, consisting of an umbrella connected via a dust collector to a smoke exhaust installation, is different from the fact that, in order to reduce the amount of exhaust gases emitted into the atmosphere,

and reduce their dustiness, it is provided with an annular manifold located on the spraying area of the furnace under the umbrella around its perimeter with a slot directed inward of the umbrella connected by a duct to the smoke exhauster

the installation located on the hydrodynamic dust collector of the bubbling type, the outlet of which is connected by pipeline to the inlet of the continuous filter, the outlet of the filter

through the pump, it is connected to the sprays introduced into the upper part of the hydrodynamic dust collector, nozzles attached to the lower part of the common collector of the inlet nozzles of the dust collector are provided with a profile recess all around the perimeter, around which are coaxially fixed to them with a gap in the bowl with openings in the lower part, and and the nozzles are rectangular in plan. Fig.1 &