SU1535896A1 - Method of reducing initial iron ore material - Google Patents

Abstract

The invention relates to metallurgy, to methods for directly producing iron from ores by their gas reduction in a shaft furnace. The purpose of the invention is to increase the productivity of the shaft furnace. The invention is carried out by carrying out additional conversion of natural gas in the intermediate zone of the shaft furnace by the oxidizing components of the process (fuel) gas and oxygen at the following volume ratios: 0.085≤N≤0.0190

0.61≤K≤0.84

0.90≤P≤1.10

0.45≤M≤0.50, where N = L / A

K = F / A

P = B / A

M = C / A according to three embodiments for converting natural gas (NG) I-URA + ^F. % CO ₂ +% H ₂ O / 100 + LO ₂

II-URA + ^B. % CO ₂ +% H ₂ O / 100

III - APG + CO ₂ , where A, F, L, B and C are the costs, respectively, of natural gas, process (fuel) gas and oxygen in the mixture and individual process (fuel) gas and oxygen

% CO ₂ +% H ₂ O / 100 - the proportion of oxidants in the process (fuel) gas. The use of the invention increases by 1.1 - 1.4 times the performance.

Description

(21) 4324661 / 31-02

(22) (U, 1 .8 /

(46) 1S.01.90. Bup. K 2

(71) Dnipropetrovsk mrtallur icic ns gut

(72) L.I. Me / iopeeiz, V.K. Simonov, Z.M. Ostrovsky, (. A. Pchelkin,. Yur o and A.A. Yurtaev

(53) 669.431.183 (038.8) (56) Patet USSR I 9311 11, hrr, (, 1 V 13/0 /, 1979.

Ptg it GSGR S 1 7994 j, cl. With 1G 1VOO,. 98 (44). GON IN CTT. / - GUN / H IRON-ORE. Bw

(7) Ichsbri reHift Ti ocHi to the metallurgy - 1.1I, i g osoSs m direct by r / chenm iron l about ud nyrei-1 IU ii gas station Lg o restored at inv-- night gch. Ueab lzobretony givyee yields productivity. PPL1 n (I. Yubuyu; it is essential to carry out additional conversion of natural gas in the intermediate zone of the shaft furnace by the oxidizing components of the process (fuel) gas and oxygen at the following ratios: 0.085 n ± 0.0190; 0.61 fc k -0.84; 0.90 p &1.10; 0.45 fc m 0.50, where n I / a; kf / a; p b / a ; t s / a according to three options for the conversion of natural gas (GHG) 1-aPG + С% CO2 + +% H O / 100 + 1 Og; H-aPG + b -% SOA +% H20 / 100; Shch-aPG + SO where a, f, i, b and c are the costs, respectively, of natural gas, of technological (fuels gas and oxygen in the mixture and individually technological (toppivny) gas and oxygen; GO, 2 +% H40 / 100 - the total amount of heat exchangers in the process (fuel) gas. Using the invention increases 1.1-1.4 times performance.

about

(ABOUT

Chz o) to metallurgy 1 pi, i- methods of direct production of iron; hz; (a and r1g hdtm of their gas inlet;; uy ein-fH, r i T.I t ur. Ni.

CR /. B nb is ate - to produce; /, m r-i ji .t-th th furnace.

From 1 to 6, they were realized according to the Midrex method as follows.

(, RPPP of organizing the process of additional korgschchi of natural gas on spongy KHot 31-g of the prospective metal-LPZYaIDRI-unrgo raw material with reducing strategies i a ;;; (its composition in the calculation of He. Not / m of the mixture,

 64%) and the gas obtained in the process of additional conversion used an installation consisting of 2 external heated reactors, to which the iron ore raw material was loaded. In the 1st reactor, the process of additional conversion of natural gas was modeled in a manner similar to the process occurring in the intermediate zone. For this, raw materials (4 g) were pre-metalized to the degree of metallization (equal to 98%, then natural gas was converted to acid by sponge iron and / or oxidized topside components

00

with about

liven gas, whose composition in terms of a 4-component mixture С0г% 19.9%; SB 22.9%:, 2%; and x 7.0%.

The change in the degree of metallization and carburizing (carbon, l) of sponge iron and the degree of conversion of natural gas (oCon Gas. Obtained in the 1st reactor, was mixed with the reduction and controlled for metallization in the 2nd reactor, where the process in the reduction zone was simulated) was controlled. , In a special series of experiments, the time of complete metallization of iron ore raw material () in the second reactor was determined.

The choice of the temperature limit for the process of additional conversion is based on a series of experiments conducted in the temperature range of 700-900 ° C. Since the temperature in the intermediate zone and in the recovery zone of the shaft furnace is almost the same, the temperature in the 1st and 2nd reactors was also maintained the same.

The research results are presented in one.

The obtained data on the switchboard i i ni i TPV on the feasibility of cpocegga in addition to the natural conversion of natural gas - fuel fuel to the exact- ing -) 1.e.e. or with a mixture of oxygen and oxygen - h

R |

temperature not lower than 760 C. In an emergency case, the tl decreases hyso M. al-enmme temperature, i.e. g h; the scrubber of the resulting reducing gases leads to the w / gasification of the process, i.e. decrease in bone size. At oxygen conversion, the temperature is not lower than 900 ° C. At lower temperatures, the process is complicated by the oxidation of sponge iron (catalyst), the absence of reducing components of the fuel (process) gas, which protects sponge iron from secondary oxidation. Spending oxygen primarily on the oxidation of iron leads, firstly, to a decrease in oxygen consumption for conversion, and secondly, to catalyst poisoning, which leads to a drop in it and a decrease in productivity of the 2nd reactor.

The choice of the boundary values of the object relations of oxygen and / or oxidizing components of the fuel (process) gas to natural gas, ensuring an increase in the productivity of the shaft furnace, is based on a series of experiments in which the gas consumption was varied.

The results are presented in table 2.

The results obtained make it possible to draw a general conclusion: with stoichiometric ratios p, n + k, m or close to them, the highest performance is achieved, i.e. T is minimal.

An increase in the degree of oxidation of the convertible (p 1.10; m 0.50; at 3% oxygen n 0.10; kv 0.84; and at 5% oxygen n 0.190; k 0.67), the decrease in the amount of reduction is r-eza, i.e. increase in ei about consumption, and therefore j and snnzhenn: about performance. Excess of natural: ase over stoichiometry (p - 0.90; with 3% oxygen, 095, k - 0.7t, with 57 oxygen and 0.170, k - 0, 61; m U, 45j leads to supernatural lero p-gpakiyu spongy The same io and the lowering of TRM by the most GWR of crystalline activity, expressed in KOH (b. Performance of the 2nd reactor also decreases. Consequently, ensuring the highest productivity occurs chrn psa; about mggric ratio of oxidizers to natural gas or close to it).

In the case of organizing the process of subsidiary conversion of natural gas and oxygen together with oxygen and oxidizing components of the fuel-technological (process) gas, the amount of oxygen introduced instead of the multivalent amount of oxidizers of the process gas is 3-5% of the volume convertible (mesi (Table 3).

The appearance of oxygen in the original

the mixture increases the rate of methane oxidation; in addition, there is a decrease in the endothermic process of additional conversion. All iro favorably affects the metallization process in the 2nd reactor. At 3% 0 in the initial mixture, the maximum degree of conversion is achieved; n the minimum metallization time. However, an increase in the oxygen content of over 5%, accompanied by a simultaneous decrease in the consumption of fuel (techno-logical) gas (in total, the ratio of oxidizing agents to natural gas remains constant, close to stoichiometry), and therefore reducing gas, causes oxidation of sponge iron, a catalyst, reducing oi KOHg and lower productivity of the 2nd reactor.

i Comparative trials of the reduction of iron ore materials using the prototype method were carried out at 760 ° C, organizing an additional conversion of natural gas fn p-ic; this JT-kmppo Hf-nt g: PC JOj, 3%, CO 8.,

Hjp 2L2. G, - 1.

Gs z ulch mouths of imcKiii in table. four.

Carrying out an iporerca of additional conversion with a value of rt-ibiioM excess of natural gas (for the prototype eng. Net; ng less than 0.07; accompanied by s / gchv,; :: cm s, i-favor iron - Kai lig. (And Synthesis of the following parameters: the controller of the degree of contrasts}, and j; pnpori, i As a result of the fuel gas at the temperature it produces the product in the reactor not lower than 760 C with the following i Thus, from the given data, the volumetric ratios are 0.095 p; s, h: w when recovering 0.190; 0, 61 k Ј 0.84; 0.90, 10; t.elez.; iHi about the raw material of the proposed 0 , 45 Јg 0.50, where n is the ratio compared with the method of hydrogen to natural gas, k - with the prototype, it is possible to achieve an increase in the perception of oxidizing components of fuel – water melting furnace in the furnace 1.1–1.4 times because of the boundaries of the slot. do they achieve

thirty

Sol -i Soko) ci iCHi; Hc erogenesis, natural -asa frr, .- preserve Hiic lso; . jju1 in r TKoi, -im lip foam - HiT o; . O: L - .i. OCSSR conversion.

gas and, accordingly, technological gases to natural gas with the addition of oxygen, ar - without the addition of oxygen, gl - the ratio of oxygen to natural gas, and with oxygen conversion, the temperature in the zone is not lower than 900 ° C.

Jt 98

 ABOUT

98 9L Q8

535896

Formula

the invention.

A method of reducing iron ore to sponge iron in a shaft furnace, including countercurrent material and gas in the reduction zones, intermediate and cooling zones, cooling, cleaning; the recycling of CO: LSHNIKOEEGO i aza with its division into technologically and fuel flows, the additional conversion of natural gas into intermediate oxidizing components — water vapor and carbon dioxide, q so that with the aim of increasing the productivity of the shaft furnace; additional conversion is carried out with oxygen and oxidizing components of the fuel gas at a temperature in the zone not lower than 760 ° C with the following volume ratios of 0.095 p 0.190; 0, 61 k Ј 0.84; 0.90 Ј, 10 0.45 Јg 0.50, where n is the ratio of oxygen to natural gas, k is the ratio of oxidizing components of the fuel;

gas and, accordingly, technological gases to natural gas with the addition of oxygen, ar - without the addition of oxygen, gl - the ratio of oxygen to natural gas, and with oxygen conversion, the temperature in the zone is not lower than 900 ° C.

Table 1

Additional conversion

LTD

65 95 99

25 19 19

3% KHT -v - DZ to the mixture

1535896

Table 3

ten

Table 4

Claims (1)

Claim. A method of recovering iron ore raw materials to sponge iron in a shaft furnace, including a counterflow of recovered material and gas in the reduction zones, the intermediate and cooling zones, cooling, cleaning and recycling of top gas with its separation into technological and fuel flows, additional conversion of natural gas in the intermediate zone oxidizing components with water vapor and carbon dioxide, q T, and the fact that, in order to increase the productivity of the shaft furnace, additional conversion is carried out oxygen and oxidizing components of the fuel gas at temperature in. an area not lower than 760 ° C with the following volumetric ratios of 0.095 Υ n <= £ 0.190; £ 0.61 to έ 0.84; 0.90 ± p έ1.10; 0.45 £ 0.50, where η is the ratio of oxygen to natural gas, k is the ratio of the oxidizing components of the fuel and, accordingly, process gases to natural gas when oxygen is added, ar is without oxygen, hl is the ratio of oxygen to natural gas, and at oxygen conversion, the temperature in the zone is not lower than 900 ° С. Table 1 , ’:() b; C j o 0 45 32 750 98 0 85 25 98 0 760 .· 8 0 90 20 98 0 800 98 0 95 19 98 0 850 98 0 95 19 900 98 0 99 19 78 0 65 25 92 0 95 19 98 0 99 19 Ί 00 00 αο 00 00 1L och cn σ> Joint venture 04 SI YU ο about L0 about With <τ -ί Yu | LO 40 ο ο ο about about ABOUT 04 σ> Joint venture Joint venture _t Joint venture Joint venture o> about 04 04 CM 04 σ \ 40 40 g * * " Ο * 04 o> Joint venture Joint venture ABOUT' SS Joint venture Joint venture o> Joint venture 04 Joint venture Joint venture ABOUT'. o < about about about about 04 about about about η With with 00 With with <o 2'0 iC ^Γ 'Ί about FROM'- SI 04 Joint venture Joint venture Joint venture ABOUT'- 04 HE Oh> from Ts 4 '> '0 about 20 Cj 00 t— <r about* about to g- with 00 OS and Joint venture 40 h0 40 about* 0h 01 * g. about l * /1 01 ♦> about about about about about but about ABOUT about ABOUT about about from·") and about cp about w about S 04 04 about about T- ' and 40 g * oo Joint venture about about about · - T “ h— t— 04 about about about about about w about about about about ABOUT Joint venture about about about about about 04 cm 04 <m Oj 04 cm CM cm about about ABOUT about cm 00 04 Joint venture 04 Joint venture Joint venture 04 Table 3 t = 760 ° C %> 0 _g in a mixture met,> s? /about eleven eleven eleven eleven eleven ! J 1 horse,%. / V M 1 98 0 93 20 about z- 98 0 97 19 s 98 0 99 18 4 98 0 99 18 5 98 0 99 18 6 95 0 92 20 7 89 0 ' 81 25 T a b l and c a 4 T = 760 ° C R % er ' ^Z I - I I u I II ¹ ? ¹ 1 ¹ 1 1 as 1 O'* con e. " % / V " M 0.5 98 9 68 26 Prototype 1,0 98 0 90 20 Proposed invention 1,5 98 0 94 24 Prototype