WO2009129653A1

WO2009129653A1 - A comprehensive recovery and utilization process for laterite-nickel ore

Info

Publication number: WO2009129653A1
Application number: PCT/CN2008/000829
Authority: WO
Inventors: 董书通
Original assignee: Dong Shutong
Priority date: 2008-04-23
Filing date: 2008-04-23
Publication date: 2009-10-29

Abstract

A metallurgical process for extracting Ni, Co, Fe from laterite-nickel ore is disclosed. It concerns a comprehensive recovery and utilization of laterite-nickel ore, comprising the following steps: A) subjecting the laterite-nickel ore to a smelting process of sulfuration to produce low grade nickel matte; B) subjecting the molten slag coming directly from the sulfuration process to a smelting process of reduction in an submerged arc furnace to produce a semi-finished steel with Fe content higher than 80%, which is then refined into qualified steel in a converter; or, putting the molten slag into an arc furnace to produce qualified steel straight away; C) subjecting the low grade nickel matte to a sulfating roasting-acid solution leaching process to produce sulfuric acid and Fe concentrate with a grade higher than 60%; D) treating the Ni/Co leaching liquor by solvent extraction to produce cobalt containing salt. By using the present invention, advantageous effects have been shown in respect of process design, comprehensive utilization of resources, economic benefit and environment protection.

Description

Comprehensive recycling method of red earth-like ore mine

The invention relates to a metallurgical method for extracting nickel, cobalt and iron from laterite nickel ore, in particular to synthesize semi-steel alloy laterite nickel ore directly from molten slag by means of ore furnace reduction technology or electric arc furnace reduction technology. Recycling method.

Background technique

The traditional laterite nickel ore extraction technology includes rotary kiln drying pre-reduction-electric furnace reduction smelting to produce ferronickel; sintering-blast furnace smelting smelting to produce low-ice nickel; sintering-blast furnace reduction smelting to produce nickel pig iron; pressurized acid leaching and reduction roasting-ammonia leaching Wait. Rotary kiln drying pre-reduction - electric furnace reduction smelting is a classic process for processing nickel laterite ore. The process is as follows:

30% nickel laterite ore is dried, dehydrated and pre-reduced at 800 ~ 900 °C in a rotary kiln, and then sent to a submerged arc furnace to reduce smelting at a high temperature of about 1550 ~ 1600 °C to produce >15% nickel. The ferronickel is further refined and enriched by the converter to more than 25% for sale to produce stainless steel. It has the characteristics of strong process adaptability, short process and high nickel recovery rate. The disadvantage is that cobalt in nickel ore cannot be recovered. The blast furnace smelting smelting is also a classic process for treating laterite nickel ore. After adding proper amount of CaO and SiO2, the nickel laterite ore is sintered into a block at about 110CTC (or extruded into a mass, naturally dried), and then blended into 10 ~ 20% of pyrite and about 20-30% of coke are smelted in a blast furnace at a temperature of about 1350 ° C to produce a low ice nickel product containing 8 to 15% nickel. Sintering - Blast Furnace Reduction Smelting is a red earth nickel ore treatment method developed on the basis of the blast furnace ironmaking process to produce nickel pig iron containing 3 to 5% nickel. The nickel laterite ore is treated by pressurized acid leaching. It is leached with sulfuric acid at high temperature (230 ~ 260 °C) and high pressure (4 ~ 5 MPa). The recovery of nickel and cobalt is usually 90% ~ 95%, but iron can not be recovered. The reduction roasting-ammonia leaching process has the reagent ΝΉ3 which can be recycled, consumes a small amount, and can comprehensively recover nickel, cobalt and iron. The low leaching rate of nickel and cobalt is its main disadvantage.

In summary, the treatment of laterite nickel ore and the comprehensive utilization of iron in laterite nickel ore, especially in the direct smelting reduction of slag in molten state to produce semi-steel alloy, domestic There is currently no in-depth research. ' Invention content

(1) Technical problems to be solved

The object of the present invention is to provide a comprehensive recycling method for laterite nickel ore with good comprehensive utilization of resources, relatively simple process and short process, in view of the lack of comprehensive utilization of resources in the traditional laterite nickel ore processing.

(2) Technical plan

In order to achieve the above object, the present invention adopts the following scheme:

The method for comprehensive recycling of a laterite nickel ore according to the present invention has the following steps:

A uses sulfurized smelting to treat laterite nickel ore to produce low ice nickel;

B 还原 Refining smelting with ore furnace to directly treat molten smelting slag in molten state to produce semi-steel alloy containing more than 80% iron, and then sent to converter for smelting into qualified molten steel; or directly treating molten state by electric arc furnace reduction smelting method Sulfurized smelting slag is qualified

C 硫酸 Sulfation roasting-acid leaching treatment of low-ice nickel to produce sulfuric acid and iron concentrate containing more than 60% iron;

D Solvent extraction of nickel and cobalt extracts to produce high purity cobalt salt products.

Wherein, the step A further comprises the steps of: transporting the laterite nickel ore to the original ore yard, first sending the rod to vibrate the feeding sieve, removing the large block of 30 mm or more, and feeding the material on the sieve directly to the blast furnace, sieving the laterite nickel ore and 5~ After mixing 10% calcium sulfate and 10% pyrite, it is extruded into a dough by a press, dried and then sent to a blast furnace together with about 20-30% coke, and smelted at a temperature of about 130 (TC). Produces low ice nickel products containing 8 to 15% nickel.

Wherein, the step B further comprises the steps of: smelting the smelting smelting slag in a molten state at about 1300 ° C directly into the submerged arc furnace, heating the electric current to above 1500 ° C, and then blowing the pulverized coal through the spray gun with compressed air and The mixture of coke reduces the iron in the slag, produces a semi-steel alloy containing more than 80% of iron, and then adds the semi-steel alloy to the converter to smelt into qualified molten steel. Wherein, the step B further comprises the steps of: directly treating the molten smelting slag in a molten state by using an electric arc furnace reduction smelting: the molten smelting smelting slag in a molten state at about 1300 ° C directly flows into the electric arc furnace, and the electric current is raised to 1500 ° Above C, the compressed air is used to spray the mixture of pulverized coal and coke through the spray gun to reduce the iron in the slag, produce a semi-steel alloy containing more than 80% of iron, and then pass oxygen through the furnace door and the furnace wall oxygen lance. Oxidation blowing is carried out to obtain qualified molten steel.

Wherein, the step C further comprises the steps of: crushing and blasting the low-ice nickel produced by the smelting and smelting of the blast furnace, and then spraying the low-ice nickel slurry into the boiling furnace by means of slurry feeding, at 550 to 600 ° C At the calcination temperature, the sulphation roasting of low-ice nickel is realized, and the flue gas is recovered into sulfuric acid; the calcined sand produced by the boiling furnace is subjected to the second-stage acid leaching, and the leaching slag produced by the slag contains more than 60% of iron, and can be used as a high-quality iron concentrate. For sale; the leachate is neutralized by calcium carbonate to remove iron, and a solution suitable for the extraction requirement can be obtained; the iron and slag is returned to the ingredients, and the pellet is used.

Wherein, the step C further comprises the steps of: selectively removing cobalt by using Cyanex 272 extractant after purifying and removing iron, and deep separation of cobalt and nickel, and carrying the organic phase containing cobalt and then extracting by hydrochloric acid or sulfuric acid, Directly produce high purity cobalt salt products.

(3) Beneficial effects

The invention is based on the new technology of "blast furnace smelting smelting" technology and "melting liquid slag ore hot electric furnace or electric arc furnace direct reduction smelting" technology, and smelting by fire method to realize nickel, cobalt and iron in laterite nickel ore. Comprehensive utilization, respectively, produces low ice nickel containing about 10% nickel and semi-steel alloy products containing more than 80% iron. The low-nickel nickel is further subjected to sulphation boiling roasting-acid leaching to produce iron concentrate, sulfuric acid and nickel-cobalt leaching solution respectively, and the nickel-cobalt leaching solution is further purified-extracted to produce a cobalt salt product and a nickel solution suitable for producing electrolytic nickel. . Therefore, the present invention has better effects in terms of process flow, comprehensive utilization of resources, economic efficiency, and environmental protection as compared with the conventional laterite nickel ore processing. DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a flow chart showing the principle of comprehensively recycling nickel, cobalt and iron from laterite nickel ore according to the present invention. detailed description

The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

The method for comprehensively recycling and utilizing laterite nickel ore according to the present invention comprises the following steps:: The laterite nickel ore is transported to the original ore yard, and the rod is first sent to the vibrating feed screen to remove a large block of 30 mm or more. The material on the sieve is directly sent to the blast furnace for treatment. The material under the sieve is mixed with appropriate amount of lime or gypsum, coke (or blue carbon) and pyrite, and sent to a hydraulic press to make a mass of 100 ~ 200mm under the pressure of about 200t, air-dried. After the blast furnace treatment.

After the sieve material of more than 30mm and the dried agglomerate are mixed with a certain proportion of coke and lime, they are directly sent to the blast furnace and smelted and smelted at about 1350 °C. The blast furnace flue gas is collected by the cyclone. The surface cooler is cooled and cooled, and the bag dust collector collects the dust, and then is absorbed by the alkali absorption tower and then emptied. The liquid slag of the blast furnace at about 1350 °C flows directly into the reduction furnace, and then is heated to about 1550 ° C, and then injected with compressed air into the pulverized coal and coke particles to achieve the agitation reduction of the liquid slag, and directly produce the semi-steel containing more than 80% of iron. alloy. The low-nickel nickel is sent to the crushing and ball milling treatment after being cast ingot by a circular casting machine.

After the ball mill, the low-ice nickel material is thickened, dehydrated and pulped, and then sent to a boiling furnace for sulfuric acid roasting. The nickel and cobalt metal sulfides in the low-ice nickel are converted into sulfate, and the iron is converted into Fe203. The flue gas is collected by the cyclone dust collection and the high temperature electric precipitator, so that the fine grain calcine contained in the flue gas is basically collected. The temperature of the flue gas after electric dust collection is about 300 ° C, and then sent to the acid production process after washing in the venturi scrubber and cooling the packed tower.

After quenching and water quenching, the nickel electrolysis solution is first subjected to a low acid leaching to control the pH of the solution to a pH of about 3, so that about 60% of nickel, cobalt and about 2% of iron are leached. The leaching solution is subjected to oxidative neutralization and iron removal, strontium carbonate removal of lead, low-ice nickel removal of copper and sodium fluoride to remove calcium and magnesium, and then subjected to extraction and cobalt removal processes to respectively produce high-purity cobalt sulfate solution and nickel sulfate solution, cobalt sulfate solution. After sodium carbonate is precipitated into cobalt carbonate, high-purity cobalt oxide is produced by high-temperature calcination. The nickel sulfate solution is sent to the nickel electrowinning workshop to produce the national standard 1 #cathode nickel.

In order to ensure high recovery rate of nickel and cobalt, a low acid leaching residue is further leached by high acid reduction, so that the leaching rates of nickel and cobalt are above 97%, and the slag contains nickel and cobalt below 0.2%. The high acid leachate is returned to a low acid leaching to consume the acid therein. Example 1

The laterite nickel ore composition used: Ni 0.8%, Fe 43%, Co 0.1%, Mg 03.65%, Si027.7%, Ca02.1%, A12O36.08%, Crl. 72%.

The smelting conditions of the blast furnace are: melting temperature 1350 ° C, coke ratio 25%, pyrite addition amount 5 ° /. , the amount of calcium sulfate added is 10%.

The electric furnace reduction smelting conditions are: melting temperature 1550 ° C, coke ratio 6%, coal ratio 8%. The sulfation roasting conditions are: calcination temperature 600 ° C, 1.1 times theoretical air volume, time

3h.

The leaching conditions were: temperature 95 ° C, sulfuric acid content 80 g L, time 2 h.

The test results are as follows: Low ice nickel contains 11.5% nickel, 1.4% cobalt, 58% iron, and 23% sulfur. The semi-steel alloy contains 85% iron and 0.6% sulfur. , containing 1% carbon, 5% silicon.

Boiling roasting flue gas contains S026.5%.

The leaching results were as follows: nickel leaching rate 97%, cobalt leaching rate 94%, and iron leaching rate 22%. Example 2

The laterite nickel ore composition used: Ni 1%, Fe 45%, Co 0.1%, Mg05.42%, Si026.9%, Ca03.2%, A12O38.02%, Cr2.22%.

The smelting conditions of the blast furnace are: melting temperature 1350 ° C, coke ratio 25%, pyrite addition amount 5%, calcium sulfate addition amount 10%.

The electric furnace reduction smelting conditions are: melting temperature 1550 ° C, coke ratio 6%, coal ratio 8 ° /. . The sulfation roasting conditions are: calcination temperature 580 ° C, 1.1 times theoretical air volume, time

3h.

The leaching conditions were as follows: temperature 95 ° C, sulfuric acid content 80 g L, time 4 h.

The test results are as follows: low ice nickel contains 12% nickel, 1.3% cobalt, 56% iron, and 22.5% sulfur. The semi-steel alloy contains 83% iron, 0.5% sulfur, 0.9% carbon, and 6% silicon.

The boiling roasting flue gas contains S026.8%.

The leaching results were as follows: nickel leaching rate 98%, cobalt leaching rate 94.5%, and iron leaching rate 30%. Example 3 The laterite nickel ore composition used: Ni l .2%, Fe 40%, Co 0.08% Mg 02.36%, Si028.7%, Ca03.2%, A12035.1%, Cr 2.46%.

The smelting conditions of the blast furnace are: melting temperature 1350 ° C, coke ratio 26%, pyrite addition 4%, calcium sulfate addition 12%.

The electric furnace reduction smelting conditions are: melting temperature 1550 ° C, coke ratio 6%, coal ratio 8%. The sulfation roasting conditions are: calcination temperature 560, 1.1 times theoretical air volume, time

4h.

The leaching conditions were: temperature 95, sulfuric acid content 80 g/L, time 4 h.

The test results are as follows: Low ice nickel contains 10.2% nickel, 1.3% cobalt, 57% iron, and 22% sulfur. The semi-steel alloy contains 83% iron, 0.7% sulfur, 1.2% carbon, and 6% silicon.

Boiling roasting flue gas contains S026.7%.

The leaching results were as follows: nickel leaching rate 96%, cobalt leaching rate 93%, and iron leaching rate 32%. Example 4

The laterite nickel ore composition used: Ni 0.75%, Fe 38%, Co 0.07%, Mg 03.16%, Si027.4%, Ca 02.8%, A12036.1%, Crl .87%.

The smelting conditions of the blast furnace are: smelting temperature 1300 Ό, coke ratio 28%, pyrite addition amount 5%, calcium sulfate addition amount 12%.

The electric furnace reduction smelting conditions are: melting temperature 1530 ° C, coke ratio 6%, coal ratio 8%. The sulfation roasting conditions are: calcination temperature 560 ° C, 1.1 times theoretical air volume, time

4h.

The leaching conditions were as follows: temperature 95 ° C, sulfuric acid content 80 g / L, time 4 h.

The test results are as follows: Low ice nickel contains 9.9% nickel, 0.9% cobalt, 58.5% iron, and 21.6% sulfur. The semi-steel alloy contains 84% iron, 0.65% sulfur, 1.1% carbon, and 5.2% silicon.

The boiling roasting flue gas contains S026.8%.

The leaching results were as follows: nickel leaching rate 97%, cobalt leaching rate 93.5%, and iron leaching rate 25%. Example 5

Composition of laterite nickel ore used: Ni 0.92%, Fe 41%, Co 0.1%, Mg 04.88%, Si029.5%, Ca03.95%, A12037.8%, Cr3.11%.

The smelting conditions of the blast furnace are: smelting temperature 1300 °C, coke ratio 26%, pyrite addition 5%, calcium sulfate addition 10%.

The electric furnace reduction smelting conditions are: smelting temperature 1550 Ό, coke ratio 6%, coal ratio 8%. The sulfation roasting conditions are: calcination temperature 560 ° C, 1.1 times theoretical air volume, time

4h.

The leaching conditions were: temperature 95 ° C, sulfuric acid content 80 g L, time 4 h.

The test results are as follows: Low ice nickel contains 11.8% nickel, 1.36% cobalt, 57.6% iron, and 23.2% sulfur. The semi-steel alloy contains 81% iron, 0.58% sulfur, 1.67% carbon, and 7.1% silicon.

The boiling roasting flue gas contains S027.1%.

The leaching results were: nickel leaching rate of 96.6%, cobalt leaching rate of 92.5%, and iron leaching rate of 28%. The process of the present invention is further illustrated by the following non-limiting examples, which are intended to be illustrative of the invention and its advantages, and are not intended to limit the scope of the invention.

Claims

Claim

1. A method for comprehensive recycling of laterite nickel ore, characterized by the following steps: A 硫化 smelting smelting to treat laterite nickel ore to produce low ice nickel;

B 还原 Reductive smelting with ore furnace to directly treat molten smelting slag in molten state to produce semi-steel alloy containing more than 80% iron, and then sent to converter for smelting into qualified molten steel; or it can be directly treated by electric arc furnace reduction smelting method The molten smelting slag of the state obtains qualified molten steel;

C using sulfuric acid roasting-acid leaching treatment of low-ice nickel to produce sulfuric acid and iron concentrate containing more than 60% iron;

D釆 Solvent extraction of nickel and cobalt extracts to produce high purity cobalt salt products.

2. The method for comprehensively recycling a laterite nickel ore according to claim 1, wherein the step A further comprises the steps of: transporting the laterite nickel ore to the original ore yard, first sending the rod vibrating feed screen, Remove the large piece above 30mm, the material on the sieve is directly sent to the blast furnace for treatment. After the sieve, the laterite nickel ore and 5-10% calcium sulfate and 10% of pyrite are mixed, and then pressed into a dough by a press, dried and then reconciled. 20 to 30% of the coke is fed into the blast furnace and smelted at a temperature of about 1300 ° C to produce a low ice nickel product containing 8 to 15% nickel.

3. The method for comprehensively recycling laterite nickel ore according to claim 1, wherein the step B further comprises the steps of: oxidizing the smelting slag of about 130 CTC in a molten state directly into the ore furnace, The electric current is raised to 1500 ° C or higher, and then the mixture of the pulverized coal and the coke is blown by the compressed air through the spray gun to reduce the iron in the slag, thereby producing a semi-steel alloy containing more than 80% of iron, and then adding the semi-steel alloy to the converter. , smelting into qualified molten steel.

4. The method for comprehensively recycling a laterite nickel ore according to claim 1, wherein the step B further comprises the steps of: directly treating the molten smelting slag in a molten state by using an electric arc furnace reduction smelting: about 1300 Å. The smelting smelting smelting slag in the molten state flows directly into the electric arc furnace, and the electric heating temperature is raised to 1500 ° C or higher. Then, the mixture of the pulverized coal and the coke is sprayed by the compressed air through the spray gun to reduce the iron in the slag, and the iron content is greater than that. 80% of the semi-steel alloy is oxidized and blown through the furnace door and the furnace oxygen lance to obtain qualified molten steel.

5. The method for comprehensively recycling laterite nickel ore according to claim 1, wherein the step C further comprises the steps of: crushing the low-ice nickel produced by the smelting and melting of the blast furnace, after ball milling, using the slurry feeding The method of spraying low-ice nickel ore slurry into a boiling furnace, at a calcination temperature of 550 600 ° C, to achieve low-ice nickel sulphation roasting, flue gas recovery to produce sulfuric acid; · boiling furnace produced calcination by two-stage acid leaching, The produced leaching slag contains more than 60% iron and can be sold as high-quality iron concentrate; the leaching solution is neutralized by calcium carbonate to remove iron, and a solution suitable for extraction can be obtained; neutralizing iron slag returning ingredients and pressing group .

6. The method for comprehensively recycling laterite nickel ore according to claim 1, wherein the step C further comprises the step of: selectively extracting cobalt by using a Cyanex 272 extractant after purifying and removing iron. The deep separation of cobalt and nickel, the cobalt-containing supported organic phase is directly extracted by hydrochloric acid or sulfuric acid, and directly produces a high-purity cobalt salt product.