CN1149629A

CN1149629A - Producing method for directly reducing iron

Info

Publication number: CN1149629A
Application number: CN 95112097
Authority: CN
Inventors: 李润生
Original assignee: ANSHAN HEAT ENERGY INST METALLURGICAL INDUSTRY MINISTRY
Current assignee: ANSHAN HEAT ENERGY INST METALLURGICAL INDUSTRY MINISTRY
Priority date: 1995-11-06
Filing date: 1995-11-06
Publication date: 1997-05-14

Abstract

The invented method is an improved pot method, the iron bearing stock, solid carbon reducer, and additive are mixed in accordance with specific proportion, then put in the semi-closed refractory pot and preheated, reduced (1250 deg.C), cooled and crushed. Said method features simple process and equipment. The yield is increased by 2-3 times.

Description

The manufacture method of direct-reduced iron

The invention belongs to field of metallurgy, relate to the manufacture method of direct-reduced iron.

The direct-reduced iron technology develops very fast in metallurgical industry, uses general.Chief editor R.M. Si Meile edits, " technology of direct-reduced iron production and application is with economic " that AISI is published, 1980, P125-126, disclose a kind of solid reductant and produced the method for direct-reduced iron, this method is feeded with two packaged type concentric tubes, being divided into three annular sections in the fire-resistant can, intermediate ring dress ferrous material, dress coke powder and Wingdale compound in outer shroud and the interior circle, what also have dresses up several bar-shaped right cylinders to ferrous material in jar, be coke powder and Wingdale compound on every side, the fire-resistant can that installs material is placed in the tunnel furnace preheating, reduction (1250 ℃), cooling, whole process needs about 48 hours, clear up fire-resistant can then, broken direct-reduced iron ring or rod, be direct-reduced iron.This method net quantity of heat is supplied with by the outside, and coke powder is only made reductive agent usefulness, though the degree of metalization height because the inherent charging method, conducts heat, mass transfer is all very slow, productivity is low, energy consumption is high, output is little.

The purpose of this invention is to provide a kind of improved loading method, not stratified in the fire-resistant can, the mixing of materials tinning, raising is conducted heat, the speed of mass transfer, boosts productivity, cuts down the consumption of energy.

The manufacture method of direct-reduced iron of the present invention comprises mixing, drying, tinning, preheating, reduction, cools off, unloads jar, crushing process, it is characterized in that said mixing is that ferrous material, solid carbonaceous reducing agent, additive are mixed in proportion; Said tinning is that handle mixes, dried material is packed semi-enclosed fire-resistant can into; Said preheating, reduction, cooling are the fire-resistant can that installs to be placed on carry out preheating, reduction, cooling in down-draft kiln or the tunnel furnace; Fixedly carbonaceous reducing agent full dose and ferrous material, additive mix in the fire-resistant can of packing into, and the dress 10mm left and right sides, upper top position carbonaceous reducing agent in fire-resistant can inboard and jar is to prevent sticking jar; Solid carbonaceous reducing agent and additive be a part and ferrous material mixing wherein, and another part and mixture layering are packed in the fire-resistant can; Additive adopts the salts substances of potassium, sodium, calcium basic metal or alkaline-earth metal.

Characteristics of the present invention and effect, this method is compared with other solid carbonaceous reduction method, saved agglomeration or made that ball operation, equipment are simple, the method for productivity ratio prior art has improved 2-3 doubly, energy consumption reduces 30-50%, be particularly suitable for 100,000 tons of following scales of annual production, therefore mixing loading process has very big applied value in the production field of direct-reduced iron.

Embodiment 1:

1). ferrous material (fine ore)

????TFe	??SiO ₂	????Al ₂O ₃	?????CaO	????MgO	??????S	??????P
????TFe	??SiO ₂	????Al ₂O ₃	?????CaO	????MgO	??????S	??????P	????70.7	????1.5	????0.3	?????0.34	????0.28	????0.070	????0.013

2). reductive agent (fine purifiation hard coal)

Total water	Analyze organic water	Ash content	Volatile matter	Full S	Fixed carbon
Total water	Analyze organic water	Ash content	Volatile matter	Full S	Fixed carbon	??8.08	????1.42	????7.0	????7.25	??＜0.3	????84.32

3). additive

Lime powder 28kg (CaO＜80%)

Su Da powder 18kg (NaCO ₃＜80%)

Take out above-mentioned fine ore 1414kg by weight, fine purifiation pulverized anthracite 300kg, lime powder 28kg, Su Da powder 18kg mixes, and the φ 200mm that packs into after the drying is in high 470mm fireclay jar or the silicon carbide jar, near tank skin position and jar upper top position dress thick fine purifiation pulverized anthracite of 10mm or coke powder, with antiseized jar, preheating in tunnel furnace then, reduction (1250 ℃), cooling, amount to 23 hours, broken afterwards direct-reduced iron.

Embodiment 2:

1) iron ore concentrate

?????TFe	??SiO ₂	????Al ₂O ₃	????CaO	?????MgO	????S	????P
?????TFe	??SiO ₂	????Al ₂O ₃	????CaO	?????MgO	????S	????P	?????67.5	??2.94	????0.57	????0.26	?????0.21	???0.146	??0.020

2). reductive agent (fine purifiation hard coal)

Total water	Analyze organic water	Ash content	Volatile matter	Full S	Fixed carbon
Total water	Analyze organic water	Ash content	Volatile matter	Full S	Fixed carbon	??5.97	????1.28	??12.91	????7.78	????＜0.5	???79.34

3). limestone powder

???CaO	????MgO	????SiO ₂	????Al ₂O ₃	?????S
???CaO	????MgO	????SiO ₂	????Al ₂O ₃	?????S	???54.12	????1.2	????1.49	????1.1	????0.04

Take out above-mentioned iron ore concentrate 1481kg by weight, fine purifiation hard coal 150kg, limestone powder 37kg mixes, adopt the prior art loading process, the compound that in φ 200mm, high 470mm fireclay jar, divides three annulars, intermediate ring to pack iron, coal, Wingdale three into, outer shroud and interior circle the two the compound of fine purifiation hard coal 50kg and limestone powder 37kg of packing into, preheating in down-draft kiln or tunnel furnace, reduction (1250 ℃), cooling amount to 34 hours, and fragmentation forms direct-reduced iron.

Claims

1. the manufacture method of a direct-reduced iron comprises mixing, drying, tinning, preheating, reduction, cools off, unloads jar, crushing process, it is characterized in that said mixing is that ferrous material, solid carbonaceous reducing agent, additive are mixed in proportion; Said tinning is that handle mixes, dried material is packed semi-enclosed fire-resistant can into; Said preheating, reduction, cooling are the fire-resistant can that installs to be placed on carry out preheating, reduction, cooling in down-draft kiln or the tunnel furnace;

2. the manufacture method of direct-reduced iron according to claim 1, it is characterized in that fixedly carbonaceous reducing agent full dose and ferrous material, additive mix in the fire-resistant can of packing into, the dress 10mm left and right sides, upper top position carbonaceous reducing agent in fire-resistant can inboard and jar is to prevent sticking jar;

3. the manufacture method of direct-reduced iron according to claim 1 is characterized in that solid carbonaceous reducing agent and additive wherein a part and ferrous material mixing, and another part and mixture layering are packed in the fire-resistant can;

4. the manufacture method of direct-reduced iron according to claim 1 is characterized in that additive adopts the salts substances of potassium, sodium, calcium basic metal or alkaline-earth metal.