RU3990U1 - FIRING MACHINE - Google Patents

Abstract

A roasting machine containing technological sections for drying, heating, calcining and cooling, passing through the continuous conveyor belt sections, a heating hearth, a transfer manifold, gas supply and exhaust caps located under the belt, blowing and vacuum chambers, characterized in that all technological sections are made with adjustable length by installing in the heating furnace above the first in the course of the tape chambers of continuous action for burning fuel with a variable coefficient air flow rate, in the first in the course of the belt blast chambers of the cooling section - batch fuel devices for the formation of a cold fuel-air jet.

Description

to given sections and layer horizons. The above causes a deterioration in the quality of finished products, an increase in fuel consumption for redistribution, and a decrease in the specific productivity of roasting equipment.

The solution of these issues is achieved njk using a roasting machine that contains technological equipment for drying, heating, roasting and cooling, continuous conveyor belt passing through the sections located above the belt, heating furnace, transfer manifold, gas supply and exhaust caps. On this machine, all technological sections are made with an adjustable length by installing continuous operation devices for burning fuel with the variable air flow coefficient above the first downstream chambers in the heating furnace, first of all, along the tape blasting chambers of the cooling section - periodic batch fuel devices for forming cold air-fuel mixture.

The essence of the proposal is to equip the heating and cooling sections with special devices with a control system for the thermal potential in the layer.

Distinctive features of the device.

All technological sections are firing. conveyor machines are made with the possibility of changing their length. This ensures high quality finished products with high redistribution when changing the mineralogical composition of the feedstock and the required composition of calcined iron ore pellets. The length of the technological sections is changed by changing the operating mode of the initial section of the heating hearth and changing the composition of the energy carrier introduced into the pellet layer at the initial section of the cooling section.

In the heating hearth, above the first chambers along the tape, continuous-acting devices for burning fuel with a variable coefficient of air flow are installed. As a result, in the initial section of the hearth, upon request, a coolant with a temperature of either 6CX) -800j or SOO.IIOOj or 1250-1350 0 is obtained, which corresponds to the regimes of either final drying, or heating, or firing, i.e. this section of the machine can work: as one of the listed technological sections. Fuel-burning devices operating with a variable coefficient of air flow are well developed by now. Their installation on roasting conveyor machines - in the initial section of the burl furnace provides the ability to control the value of thermal and temperature potential in the layer (at the head section of the roasting conveyor).

 In the first downstream blast chambers of the cooling section, batch fuel devices were installed to form a cold toshvovozdvorodnoy mixture with its subsequent introduction into the pellet layer J by ignition from the red-hot layer and burning directly in the pellet layer. This device is a batch device. So, with the exception of the supply of natural gas to the chambers (through gas distribution pipes), this section acts as the first stage of the cooling section, and when the natural gas is fed into the chambers, the section acts as the final stage of the firing section with the combustion of the air-fuel mixture at the lower horizons of the layer. provides regulation of the length of both the firing section and the cooling section.,

The proposal is illustrated by a drawing, which shows a schematic diagram® (longitudinal section) of a regional conveyor belt 1 with an adjustable length of individual technological zones. The machine consists of sections - drying I, heating 2, firing 3, cooling 4, passing through them a continuous conveyor belt 5 located above the heating hearth belt 6 with fuel-burning devices - high temperature - 7 and adjustable temperature range 8, overflow manifold 9 with lower pipes 10, caps for supply II and removal of 12 gas flows located under the tape d; sewage 13 and vacuum 14 chambers. In the blast chambers of the initial section of the cooling section, gas-distributing pipes of fuel devices 15 are placed. The calcining machine operates as follows. Crude iron ore pellets are loaded onto a conveyor belt 5 and subsequently dried in section I, heated in section 2, step-fired in section 3 and combined cooling in section 4. The heat transfer medium to the first slurry: sush1sh is fed through hood II, filtered through a layer from top to bottom and the exhaust gases are discharged into the chimney. In a separate part of the drying section, the coolant is fed through the blast chambers 13, filtered through a layer from the bottom, up and thrown into the chimney through the hood. In the heating section 2, the fuel combustion devices 8 operate with a high air flow coefficient and provide the formation of a heat carrier with a temperature of 600-800 ° C. This coolant is filtered through a layer from top to bottom and is recycled through vacuum chambers 14.

900-IIOO C, in the second - I250-I350 ° C. At the same time, the movement of the coolant flows unchanged.

In the firing section 3, the coolant is obtained by burning the air-fuel mixture in the burners 7, filtered through a layer. From top to bottom and taken for recycling through vacuum chambers, collectors and smoke exhausters,

In the cooling section 4 in its initial section through the blast chambers serves atmospheric air. This air may, if necessary, be diluted with exhaust high-temperature gases. The resulting gas-air mixture (hereinafter referred to as the cooler) is fed into the layer, filtered through it from the bottom up §§ §§ ol 1ak is diverted to the manifold 9, formed by collector 9 is fed into the heating furnace 6 and is used as a coolant in the firing zone. The described operating mode of the initial section of the cooling section corresponds to the first stage of pellet cooling and is used if necessary for a soft and long process of cooling the layer.

The initial section section 4 can also be used as a final firing section during the burning of natural gas directly at the lower horizons of the pellet layer. To do this, through the gas-distributing pipes of the fuel devices 15, natural gas is supplied, the gas is turned into an upward flow of the gas-air mixture, and a cold nausea-air mixture is formed. This mixture is introduced into the layer, which ignites the hot areas and burns directly in the layer of pellets. Subsequent modes of movement and use of exhaust gases in this section remain unchanged.

At the final stage of the cooling section 4, atmospheric air is fed into the pellet layer through the blast chambers, filtered through the layer from the bottom up and removed through the cap 12 for recycling, usually in a drying sequence.

Cooled pellets are unloaded from the conveyor belt 5 and sent to the warehouse of blanks of finished products.

The application of the proposed utility model makes it possible to use a firing conveyor machine for the production of pellets with wide fluctuations of the raw material composition and to obtain high-quality finished products with high technical and economic indicators.

.7

Claims (1)

A roasting machine containing technological sections for drying, heating, calcining and cooling passing through continuous conveyor belts, heating horns, transfer manifolds, gas supply and exhaust caps located under the belts, blasting and vacuum chambers, characterized in that all technological sections are made with adjustable length by installing in the heating furnace above the first in the course of the tape chambers of continuous action for burning fuel with a variable coefficient air flow rate, in the first in the course of the belt blast chambers of the cooling section - batch fuel devices for the formation of a cold fuel-air jet.