RU2164948C1 - Apparatus for distributing fuel additives in tuyeres of blast furnace - Google Patents

Abstract

FIELD: ferrous metallurgy, namely, apparatuses for making cast iron in blast furnaces with use of fuel additives, possibly with use of mixed compositions. SUBSTANCE: apparatus includes first and second gas ducts provided with manually controlled damper, metering orifice, electrically driven shutter, non-return valve and regulating throttle. First gas duct is joined with first manifold for distributing gas through supply passages to each tuyere. Second manifold for distributing gas is joined with second gas duct. Supply passages of each tuyere of first manifold have second non-return valve. Supply passages of each tuyere of second manifold include manually controlled damper, metering orifice, non-return valve. Three-way valve is built-in to pipeline of supply passage of respective tuyere of first manifold between second non-return valve and regulating throttle. EFFECT: enhanced efficiency of making cast iron with lowered consumption of coke. 1 dwg, 3 ex

Description

 The claimed invention relates to the field of ferrous metallurgy, in particular to devices for the production of pig iron in blast furnaces using the injection of highly heated oxygen-rich blast and fuel additives.

 Widely known are devices for distributing fuel additives by tuyeres of a blast furnace containing a gas pipeline of either natural gas (Klempert V.M. Automation of a blast furnace. - M.: Metallurgy, 1965, pp. 140-145), or coke oven gas, which are embedded in the corresponding a collector with subsequent branching and introduction of a corresponding pipeline into each tuyere of a blast furnace (Pashinsky V. F., Tovarovsky I. G. et al. Blast furnace with coke gas injection. - Kiev: Technique, 1991, pp. 42-43).

 The main disadvantage of the above devices is that they do not have the possibility of blast furnace smelting using injection of both natural and coke oven gases into the furnace. This leads to energy losses, to losses in pig iron production and an increase in coke consumption.

 Closest to the claimed device is a device for distributing fuel additives by the tuyeres of a blast furnace, including the first and second gas pipelines equipped with a manual gate valve, a measuring diaphragm, an electrified gate valve, a check valve and a regulating throttle, the first gas distribution manifold along the exhaust channels to each tuyere equipped a manual valve, a measuring diaphragm, a control throttle and a first non-return valve, the first gas pipeline being connected to the first manifold of the distribution gas production (Pashinsky V.G. et al. Blast furnace smelting with blasting of blast furnace gas. - Kiev: Technique, 1991, pp. 35-36).

 The disadvantage of this device is the low efficiency of their use due to restrictions in the ratio of coke and natural gases in the event of an excess of gas in the coke production.

 The supply of a mixture of coke and natural gases to the tuyere source causes unstable operation of the furnace. An example is the operation of an Edgar Thomson factory furnace of US Steel, USA, and one Australian furnace (EL Maddalena, RR Terza, TF Sobek and KL Myklebust. Blowing coke oven gas into blast furnaces. Iron and Steelmaker, 1995, 22, N 10, p . 93-95).

 After the gas mixture was supplied, the furnace started to work unstably, coke consumption increased, production decreased.

 Having made the transition to blowing gas of the same type, the furnace was stabilized.

 The problem solved by the invention is to increase the production of pig iron and reduce the consumption of coke by ensuring a stable operation of the blast furnace and highly efficient use of excess coke oven gas of the coke production.

 This object is achieved in that in a device for distributing fuel additives by tuyeres of a blast furnace, including the first and second gas pipelines equipped with a manual gate valve, a measuring diaphragm, an electrified gate valve, a check valve and a regulating throttle, the first gas distribution manifold along the exhaust channels to each tuyere, equipped with a manual gate valve, a measuring diaphragm, a control throttle and a first non-return valve, the first gas pipeline being connected to the first gas distribution manifold a, according to the invention, the device is additionally equipped with a second gas distribution manifold connected to the second gas pipeline, a second check valve introduced into the outlet channels of each lance of the first gas distribution manifold between the measuring diaphragm and the control choke, a manual valve, a measuring diaphragm, a check valve inserted into the outlet channels of each lance of the second manifold of gas distribution, and a three-way valve cut into the pipe of the outlet channel of the corresponding lance of the first a gas distribution manifold between the second check valve and the control throttle.

 A diagram of the claimed device is shown in the drawing.

 The proposed device consists of a blast furnace 1 with an annular air duct of blast 2, which is connected through an elbow to an air lance 19, which is connected to a gas pipe 18 common to each lance 19, equipped with a check valve 17, a control valve 16 and a three-way valve 20. Each three-way valve 20 each tuyeres 19 are connected to the outlet channels 12 of the first 9 and second 11 of the tuyere gas distribution manifolds.

 Each outlet channel 12 is equipped with a manual valve 13, a measuring diaphragm 14 and a check valve 15.

 The first 9 and second 11 collectors on the other hand are connected respectively to the first 8 and second 10 gas pipelines, each of which is equipped with a manual valve 3, a measuring diaphragm 4, an electrified valve 5, a check valve 6 and a control throttle 7 in the direction of the gas.

 The proposed device for conducting blast furnace smelting is as follows.

 Natural and coke oven gases from pipelines enter the first 8 and second 10 gas pipelines, where, with open manual valves 3 and electrified valves 5, passing through non-return valves 6, they respectively enter the first 9 and second 11 tuyere gas distribution manifolds 1. ..n.

 At the same time, in each gas pipeline 8 and 10, a predetermined flow rate of the corresponding gas is automatically maintained using the measuring diaphragms 4 and using control chokes 7.

 Flow-stabilized natural and coke gases from the first 9 and second 11 collectors when open to the corresponding side of the three-way valve 20, through manual valves and check valves, are separately fed through the common gas pipeline to the tuyeres of the blast furnace, where they are mixed with hot blast.

 At the same time, the necessary ratio is maintained: for natural gas - one volume per lance, and for coke - two volumes, using measuring diaphragms 14 and a regulating throttle in remote control mode.

 Thus, using a three-way valve 20, setting it to the “open” position towards the tuyeres for supplying natural gas and on the other tuyeres toward the coke oven gas, process personnel have the opportunity to use different amounts of coke oven gas by replacing natural gas, choosing different the number of tuyeres with the formation of tuyere feed groups of one or another fuel component.

 In the operation of the furnace, feeding into air lances, the amount of which is 24 pcs., Of heated oxygen-enriched blast with injection of fuel additives: natural gas, is used.

When using only natural gas, it is supplied through the first gas line 8 (see drawing), the first gas distribution manifold 9 through the exhaust channels 12 and the common gas pipe 18 to the tuyeres 19 of the blast furnace 1. The total natural gas consumption, measured by the diaphragm 4, s the regulating throttle 7 is maintained constant and equal to 13050 nm ³ / h, in the automatic mode, the open three-way cock 20 in the feeding direction of natural gas per tuyere 19, gas flow rate per tuyere, equal to 544 nm ³ / h and the measured phrenic my 14 and mounted with the regulating throttle 16 in the remote control mode for each tuyeres 19 of blast furnace 1.

 Example 1. On a blast furnace 1, coke oven gas is supplied through a second gas pipeline 10, a second manifold 11 for distributing gas through the exhaust channels 12 according to the number of tuyeres. At the same time, the overall ratio of the costs of natural gas and coke per furnace was set equal to 1: 2.8.

The total consumption of natural gas was 5470 nm ³ / h, and coke 15,225 nm ³ / h. Natural gas is supplied per ten tuyeres through approximately one tuyere into which coke oven gas is supplied and the number of tuyeres with coke-oven gas is 14 tuyeres.

The total consumption of natural gas to the furnace - 5470 nm ³ / h and coke oven gas - 15225 nm ³ / h in automatic control mode are supported by control chokes 5 in the first and second gas pipelines, respectively.

The consumption of natural gas is 545 nm ³ / h for each of ten tuyeres and the consumption of coke oven gas for each of fourteen tuyeres is 1090 nm ³ / h. Applied to the lance using three-way valves 20, is installed by measuring diaphragms 14 and regulating chokes 17 in remote control mode.

 From this it can be seen that using the proposed method and device for its implementation, the features described in the prototype are realized: blowing into the tuyeres of a blast furnace of natural and coke oven gas is carried out at a gas flow rate in the main gas pipelines close to 1: 3.

Example 2. Differences from the conditions specified in example 1 are:
The predetermined ratio of the costs of natural gas and coke oven gas, respectively, in the first 8 and second gas pipelines 1: 2. The total consumption of natural gas is 6525 nm ³ / h, coke oven gas - 13050 nm ³ / h.

The gas supply is carried out through each tuyere, respectively, of natural and coke oven gas using a three-way valve 20 at a cost of 545 nm ³ / h for each tuyere of natural gas; coke - 1090 nm ³ / h, i.e. natural gas is supplied for every 12 tuyeres and coke oven gas for every 12 tuyeres.

 Example 3. The specified ratio of the total costs of natural and coke oven gases - 1: 6.

The consumption of natural gas - 3265 nm ³ / h and coke oven gas - 19590 nm ³ / h is supported in the first 8 and second 10 gas pipelines. Natural gas is supplied every two tuyeres into which coke oven gas is supplied, i.e. six tuyeres - natural gas and eighteen tuyeres - coke oven gas, respectively, with a consumption of 545 nm ³ / h and 1090 nm ³ / h for each tuyere.

 The results of examples 2 and 3 indicate that by changing the number of tuyeres in the tuyere groups of natural and coke oven gas and the corresponding change in gas flow in gas pipelines, you can have virtually any quantitative use of coke oven gas.

 The introduction of the proposed device will allow, when replacing natural gas with coke oven, to stabilize the course of blast furnaces, make fuller use of the excess coke oven gas in the energy sector of the enterprise and, if there are oxygen production capacities for blast enrichment, operate blast furnaces at their maximum capacity.

Claims (1)

 A device for distributing fuel additives by the tuyeres of a blast furnace, including the first and second gas pipelines equipped with a manual gate valve, a measuring diaphragm, an electrified valve, a check valve and a regulating throttle, a first gas distribution manifold along the exhaust channels to each tuyere equipped with a manual valve, a measuring diaphragm, control throttle and the first non-return valve, and the first gas pipe is connected to the first gas distribution manifold, characterized in that it further equipped with a second gas distribution manifold connected to the second gas pipeline, a second non-return valve introduced into the outlet channels of each lance of the first gas distribution manifold between the measuring diaphragm and the control choke, a manual valve, a measuring diaphragm, a non-return valve inserted into the outlet channels of each lance of the second distribution manifold gas, and a three-way valve embedded in the pipe of the outlet channel of the corresponding lance of the first manifold of gas distribution between the second return throttle valve and control throttle.