A comprehensive utilization system of laterite nickel ore suspension roasting-smelting

Abstract

A comprehensive utilization system for suspended roasting and smelting of laterite nickel ore belongs to the field of mining and metallurgical engineering. In the system, a feed bin is connected to a pulverizer, a discharge port of the pulverizer is connected to a feed port of a cyclone preheater through a pipeline, a discharge port of the cyclone preheater is connected to an air lock valve, an air lock valve is connected to a suspended heating roaster, a discharge port of the suspended heating roaster is connected to a cyclone separator, an air outlet of the cyclone separator is connected to an air inlet of the pulverizer, a discharge port of the cyclone separator is connected to a suspended reduction roaster, a discharge port of the suspended reduction roaster is connected to a smelter, and an exhaust port of the smelter is connected to an air inlet of the suspended heating roaster. The system can efficiently and energy-savingly extract nickel iron from laterite nickel ore, and is particularly capable of processing laterite nickel ore with a nickel grade of 0.4 to 3.

Description

Technical Field

[0001] The invention specifically relates to a comprehensive utilization system of laterite nickel ore suspension roasting-smelting, and belongs to the field of mining and metallurgical engineering. Background Art

[0002] As a key metal in the fields of new energy vehicles, new materials, chemical catalysis, etc., the demand for nickel has increased dramatically. Simply developing easy-to-mine high-grade nickel sulfide ores can no longer meet the needs of development. As a common nickel ore with a wide distribution, laterite nickel ore accounts for more than 70% of the world's total nickel ore resources. Since 2010, the output of laterite nickel ore has exceeded that of sulfide nickel ore, and it has been gradually increasing. However, due to technical reasons, the development of laterite nickel ore can still be further improved. At present, laterite nickel ore mainly includes high-iron and low-nickel limonite-type nickel ore and high-nickel and low-iron silicon-magnesium nickel ore. Common laterite nickel ore treatment methods include wet treatment and pyrotreatment. Wet treatment includes high-pressure acid leaching, atmospheric pressure acid leaching, reduction-ammonia leaching, etc. The main problems of wet treatment are low nickel-iron recovery rate and poor process environmental protection. Due to the use of strong acid, the equipment involved in the process is severely corroded, and it is seriously polluting and seriously damages the environment. The most widely used pyrometallurgical method for treating laterite nickel ore is the rotary kiln-electric furnace smelting method (RKEF). The laterite nickel ore is fed into the electric furnace after reduction roasting in a rotary kiln. However, due to the high energy consumption and easy accumulation of ore materials in the rotary kiln, the process is complicated, inefficient and costly. Therefore, the development of a new process system for treating laterite nickel ore is the focus of research by practitioners in this industry.

[0003] Patent 201710048798.0 discloses a process for directly reducing laterite nickel ore particles using a rotary kiln. The laterite nickel ore is mixed with a carbonaceous reducing agent, a binder, etc. to form granules, which are then sent to a rotary kiln for direct reduction roasting. The resulting product is then cold extracted and then ore selected. This method has two sections of climbing in the rotary kiln, and the material speed can be significantly slowed down, which improves the degree of metal reduction and enrichment. However, due to insufficient heating in the rotary kiln and the occurrence of ring formation, the nickel-iron metal recovery rate is low, only about 80%. In addition, impurities such as coal, lime, and binders are added during the heating process, resulting in a large amount of waste and increased costs.

[0004] In view of the problems existing in the current process system for processing laterite nickel ore, the present invention provides a system for processing laterite nickel ore with high efficiency, environmental protection and low energy consumption, so as to realize the comprehensive recycling and utilization of difficult-to-process laterite nickel ore resources to the greatest extent. Summary of the invention

[0005] Aiming at the problems of high cost, low efficiency, large energy consumption and serious pollution in the existing laterite nickel ore pyrometallurgical treatment technology, the invention provides a laterite nickel ore suspension roasting-smelting comprehensive utilization system, which can extract nickel iron from the laterite nickel ore with high efficiency and energy saving, and is particularly capable of treating laterite nickel ore with a nickel grade of 0.4-3.

[0006] The comprehensive utilization system of laterite nickel ore suspension roasting-smelting of the present invention comprises a feed bin, a pulverizer, a cyclone preheater, an air lock valve, a suspension heating roasting furnace, a cyclone separator, a suspension reduction roasting device, and a smelter;

[0007] The feed bin is connected to the pulverizer, the discharge port of the pulverizer is connected to the feed port of the cyclone preheater through a pipeline, the discharge port of the cyclone preheater is connected to the air lock valve, the air lock valve is connected to the suspension heating roasting furnace, the discharge port of the suspension heating roasting furnace is connected to the cyclone separator, the air outlet of the cyclone separator is connected to the air inlet of the pulverizer, the discharge port of the cyclone separator is connected to the suspension reduction roasting machine, the discharge port of the suspension reduction roasting machine is connected to the smelting machine, and the exhaust port of the smelting machine is connected to the air inlet of the suspension heating roasting furnace.

[0008] Furthermore, the comprehensive utilization system of laterite nickel ore suspension roasting-smelting also includes a feeding belt, and the feeding bin is connected to the feeding port of the grinding mill through the feeding belt.

[0009] Preferably, the pulverizer is a vertical pulverizer.

[0010] Furthermore, the comprehensive utilization system of laterite nickel ore suspension roasting-smelting also includes a dust collector, an induced draft fan and a chimney;

[0011] The air outlet of the cyclone preheater is connected to the feed inlet of the dust collector, the air outlet of the dust collector is connected to the induced draft fan, the induced draft fan is connected to the chimney; the discharge port of the dust collector is connected to the feed inlet of the cyclone separator through a pipeline.

[0012] Furthermore, the comprehensive utilization system of laterite nickel ore suspension roasting-smelting also includes a combustion station, which is arranged at the bottom of the suspension heating roasting furnace and is provided with gas and air inlets. The combustion station is used to provide roasting heat to the suspension heating roasting furnace.

[0013] Furthermore, a nitrogen inlet and a coal gas inlet are provided in the suspension reduction roaster; and a gas outlet of the suspension reduction roaster is connected to the suspension heating roaster.

[0014] Preferably, the smelting machine is an electric furnace smelting machine.

[0015] Furthermore, the smelting machine is provided with a molten iron inlet and a slag inlet.

[0016] In the comprehensive utilization system of laterite nickel ore suspension roasting-smelting, thermocouple temperature measuring devices and pressure sensor devices are provided inside the suspension heating roaster, suspension reduction roaster, cyclone preheater and cyclone separator, and the temperature of each temperature measuring point and the pressure of each pressure measuring point can be monitored in real time by a computer.

[0017] The method for using the comprehensive utilization system of laterite nickel ore suspension roasting-smelting of the present invention is carried out according to the following steps:

[0018] S1: Grinding and Dehydration

[0019] First, the laterite nickel ore is fed from the feed bin into the vertical grinding mill and crushed to a mineral particle size of less than -2mm. The ore powder is carried into the cyclone preheater through a pipeline by the gas discharged from the cyclone separator for drying and dehydration. The preheating temperature is 100-300℃ and the residence time is 10-20s. The main reactions that may occur are as follows.

[0020] (Ni,Mg)O·SiO 2 ·H 2 O=(Ni,Mg)O·SiO 2 +H 2 O(g)

[0021] S2: Suspended heating roasting

[0022] The laterite nickel ore preheated by the cyclone preheater is fed into the suspension heating roaster through the air lock valve, and air and gas are introduced from the bottom of the suspension heating roaster and ignited at the combustion station. The laterite nickel ore powder is in a suspended state in the suspension heating roaster. The temperature in the stable furnace is 1000-1200℃, and the roasting time is 5-20s. The laterite nickel ore is freed of impurities such as crystal water and hydroxyl groups to obtain the material after heating and impurity removal. The gas generated during the heating process in the suspension heating roaster is fed into the cyclone separator for separation, and then sent to the pulverizer to bring the ore powder into the cyclone preheater for preheating. The main reactions that may be involved in the raw materials and dehydrated products in the laterite nickel ore in the suspension heating roaster are:

[0023] (Mg,Fe,Ni) 3 Si 2 O 5 (OH)→(Mg,Fe,Ni)SiO 3 +(Mg,Fe,Ni) 2 SiO 4 +2H 2 O

[0024] Ni 3 Mg 3 Si 2 O 5 OH(s)→3NiO(s)+3MgO(s)+4SiO 4+4H 2 O(g)

[0025] (Ni,Mg)O·SiO 2 →NiO+MgO+SiO 2

[0026] S3: Thermal storage reduction

[0027] The heated and impurity-removed material is fed into the cyclone separator, and the heating gas is discharged from the upper outlet and fed into the pulverizer. The material is discharged from the lower outlet and fed into the suspension reduction roaster. A nitrogen and coal gas mixture is introduced into the bottom of the suspension reduction roaster. The mineral itself stores heat during the heating stage, so that the mineral reacts with the mixed gas in a suspended state. The reduction temperature is controlled at 800-1100°C, and the roasting time is 20-60 minutes to obtain the reduced material. The gas generated during the reduction process is discharged from the side and fed into the suspension heating roaster as heating gas. The main chemical reaction equations that may be involved are:

[0028] NiO+CO=Ni+CO 2

[0029] CoO+CO=Co+CO 2

[0030] 3Fe 2 O 3 +CO=2Fe 3 O 4 +CO 2

[0031] Fe 3 O 4 +CO=3FeO+CO 2

[0032] Fe 3 O 4 +4CO=3Fe+4CO 2

[0033] FeO+CO=Fe+CO 2

[0034] S4: Smelting

[0035] The reduced material is fed into a smelting machine for smelting at a temperature of 1300-1600°C for 30-50 minutes. The molten iron and slag generated by smelting are discharged from the molten iron outlet and the slag outlet respectively. The gas generated during the smelting process is fed into a suspension heating roasting furnace as a heating gas.

[0036] In S1 of the above method of use, the feed particle size is not greater than 30 mm.

[0037] In S2 in the above-mentioned method of use, the coal gas is one of coke oven gas, blast furnace gas, natural gas cracking gas, and coal gas.

[0038] In S2 of the above method of use, the volume concentration of coal gas during the suspension heating and roasting process is 10% to 30%.

[0039] In S3 of the above-mentioned method of use, the coal gas is one of coke oven gas, blast furnace gas, natural gas cracking gas, and coal gas.

[0040] In S3 of the above-mentioned method of use, during the heat storage reduction stage, the amount of coal gas introduced is 0.2-0.6 m / s according to the mass ratio of the total volume of reducing gas in the coal gas to the mass ratio of the laterite nickel ore powder in the reduction roaster. 3 / kg, the nickel-iron metallization rate reaches 60-95%.

[0041] In the above method of use, the nickel recovery rate is greater than 95%, and the iron recovery rate is greater than 90%.

[0042] Compared with the current traditional pyrometallurgical processes such as rotary kiln-electric furnace roasting to treat laterite nickel ore, the present invention adopts gas-based suspension roasting pre-reduction-smelting technology, and controls the reduction efficiency by adjusting the roasting parameters during grinding dehydration, suspension heating roasting, and heat storage reduction. The process creatively introduces the crushing and grinding function as an important part of the closed-loop system, and the gas and heat generated in the process can be maximized. The utilization, shortening the process flow, improving efficiency, and reducing costs. The process adopts suspension heating roasting technology, which can effectively avoid the problems of poor uniformity, uneven heating, high energy consumption, etc. existing in rotary kiln roasting. At the same time, the process makes full use of the heat storage of the mineral during the suspension heating roasting process. In the heat storage reduction stage, no fuel needs to be added, and the full reduction of the mineral can be achieved, and the metallization rate is significantly improved. In addition, gas-based roasting is used in both the suspended heating roasting and heat storage reduction stages, which reduces the use of fuels such as coke, avoids the impact of impurities such as sulfur in fossil fuels on the roasting process, improves environmental protection, and reduces pollution. The gas generated during the roasting and smelting process can be used as a heating gas for the suspended heating roasting and preheating process, solving the problems of tail gas emissions, secondary pollution, and high energy consumption in the pyrometallurgical treatment process, and realizing continuous hot delivery of materials in a closed state. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 The schematic diagram of the structure of the comprehensive utilization system of laterite nickel ore suspension roasting-smelting is shown in the figure: 1-feeding bin, 2-feeding belt, 3-vertical grinding mill, 4-cyclone preheater, 5-air lock valve, 6-suspension heating roasting furnace, 7-cyclone separator, 8-suspension reduction roasting machine, 9-combustion station, 10-electric furnace smelting machine, 11-dust collector, 12-induced draft fan, 13-chimney. DETAILED DESCRIPTION

[0044] The present invention is further described in detail below in conjunction with embodiments.

[0045] The comprehensive utilization system of laterite nickel ore suspension roasting-smelting adopted in this invention is in accordance with the above Figure 1 Built as shown.

[0046] It includes: a feeding bin 1, a feeding belt 2, a vertical grinding mill 3, a cyclone preheater 4, an air lock valve 5, a suspended heating roasting furnace 6, a cyclone separator 7, a suspended reduction roasting device 8, a combustion station 9, an electric furnace smelting machine 10, a dust collector 11, an induced draft fan 12, and a chimney 13.

[0047] The feed bin 1 is connected to the feed port of the vertical grinding mill 3 through a feeding belt 2, and the discharge port of the vertical grinding mill 3 is connected to the feed port of the cyclone preheater 4 through a pipeline.

[0048] The upper air outlet of the cyclone preheater 4 is connected to the feed port of the dust collector 11, the discharge port of the dust collector 11 is connected to the feed port of the cyclone separator 7 through a pipeline, the air outlet of the dust collector 11 is connected to the induced draft fan 12, and the discharge port of the induced draft fan 12 is connected to the chimney 13.

[0049] The lower discharge port of the cyclone preheater 4 is connected to the air inlet of the air lock valve 5, the discharge port of the air lock valve 5 is connected to the feed port of the suspension heating roasting furnace 6, the discharge port of the suspension heating roasting furnace 6 is connected to the feed port of the cyclone separator 7 through a pipeline, and the upper discharge port of the cyclone separator 7 is connected to the air inlet of the vertical grinding mill 3.

[0050] The lower discharge port of the cyclone separator 7 is connected to the feed port of the suspension reduction roaster 8, the discharge port of the suspension reduction roaster 8 is connected to the feed port of the electric furnace smelting machine 10, the air outlet of the suspension reduction roaster 8 is connected to the suspension heating roasting furnace 6; the exhaust port of the electric furnace smelting machine 10 is connected to the bottom air inlet of the suspension heating roasting furnace 6.

[0051] In the device, a combustion station 9 is provided at the bottom of the suspension heating roasting furnace 6 and connected to coal gas and air. Two air inlets are provided at the bottom of the suspension reduction roasting device 8 and connected to nitrogen and coal gas sources respectively.

[0052] The electric furnace smelting machine 10 is provided with a molten iron inlet and a slag inlet.

[0053] The method for using the comprehensive utilization system of laterite nickel ore suspension roasting-smelting in this embodiment uses laterite nickel ore whose main components contain Ni 0.88% and Fe 52.62% by mass, and the feed particle size of the laterite nickel ore is p80=25 mm.

[0054] S1: First, the laterite nickel ore is fed from the feed bin 1 into the vertical grinding mill 3 and crushed to a mineral particle size of less than -2 mm. The ore powder is carried by the gas discharged from the cyclone separator 7 through a pipeline into the cyclone preheater 4 for drying and dehydration. The preheating temperature is 200°C and the residence time is 10s.

[0055] S2: The laterite nickel ore preheated by the cyclone preheater 4 is fed into the suspension heating roasting furnace 6 through the air lock valve 5, and air and coal gas are introduced from the bottom of the suspension heating roasting furnace 6 and ignited, and the laterite nickel ore powder is in a suspended state in the furnace. The temperature in the furnace is stabilized at 1200°C, the roasting time is 5s, the volume concentration of coal gas in the suspension heating roasting furnace 6 is 30%, and the laterite nickel ore is freed of impurities such as crystal water and hydroxyl groups. The gas generated during the heating process in the suspension heating roasting furnace 6 is fed into the cyclone separator 7 for separation, and then sent to the vertical pulverizer 3 to bring the ore powder into the cyclone preheater for preheating.

[0056] S3: The material after heating and impurity removal is fed into the cyclone separator 7, and the heated gas is discharged from the upper discharge port and fed into the vertical grinding mill 3. The material is discharged from the lower discharge port and fed into the suspension reduction roaster 8. A nitrogen and coal gas mixture is introduced into the bottom of the suspension reduction roaster 8. The mineral itself is used to store heat during the heating stage, so that the mineral reacts with the gas in a suspended state. The reduction temperature is controlled at 900°C, the roasting time is 40 minutes, and the amount of coal gas introduced is 0.4m3 / s according to the mass ratio of the total volume of the reducing gas in the coal gas to the mass ratio of the laterite nickel ore powder in the suspension reduction roaster 8. 3 The gas generated during the reduction process is discharged from the side and fed into the suspension heating calcining furnace 6 as heating gas.

[0057] S4: The reduced material is fed into an electric furnace smelter 10 for smelting at a temperature of 1400°C for 40 minutes. The molten iron and slag generated by the smelting are discharged from the molten iron outlet and the slag outlet respectively. The gas generated during the electric furnace smelting process is fed into the suspension heating roasting furnace 6 as a heating gas. The nickel recovery rate is 96.5%, and the iron recovery rate is 91.5%.

[0058] Example 2

[0059] The comprehensive utilization system of laterite nickel ore suspension roasting-smelting in this embodiment is the same as that in Example 1.

[0060] The comprehensive utilization method of laterite nickel ore suspension roasting-smelting in this embodiment is:

[0061] The main components of the laterite nickel ore used in this embodiment contain Ni 1.85% and Fe 30.24% by weight, and the feed particle size of the laterite nickel ore is p80=30 mm.

[0062] S1: First, the laterite nickel ore is fed from the feed bin 1 into the vertical grinding mill 3 and crushed to a mineral particle size of less than -2 mm. The ore powder is carried by the gas discharged from the cyclone separator 7 through a pipeline into the cyclone preheater 4 for drying and dehydration. The preheating temperature is 300°C and the residence time is 5s.

[0063] S2: The laterite nickel ore preheated by the cyclone preheater 4 is fed into the suspension heating roasting furnace 6 through the air lock valve 5, and air and coal gas are introduced from the bottom of the suspension heating roasting furnace 6 and ignited, and the laterite nickel ore powder is in a suspended state in the furnace. The temperature in the furnace is stabilized at 1100°C, the roasting time is 5s, the volume concentration of coal gas in the suspension heating roasting furnace 6 is 35%, and the laterite nickel ore is freed of impurities such as crystal water and hydroxyl groups. The gas generated during the heating process in the suspension heating roasting furnace 6 is fed into the cyclone separator 7 for separation, and then sent to the vertical pulverizer 3 to bring the ore powder into the cyclone preheater for preheating.

[0064] S3: The material after heating and impurity removal is fed into the cyclone separator 7, and the heated gas is discharged from the upper discharge port and fed into the vertical grinding mill 3. The material is discharged from the lower discharge port and fed into the suspension reduction roaster 8. A nitrogen and coal gas mixture is introduced into the bottom of the suspension reduction roaster 8. The mineral itself is heat stored in the heating stage, so that the mineral reacts with the gas in a suspended state. The reduction temperature is controlled at 1000°C, the roasting time is 20 minutes, and the amount of coal gas introduced is 0.4m3 / s according to the mass ratio of the total volume of the reducing gas in the coal gas to the mass ratio of the laterite nickel ore powder in the suspension reduction roaster 8. 3 / kg, the gas generated during the reduction process in the suspension reduction roaster 8 is discharged from the side and fed into the suspension heating roaster 6 as heating gas.

[0065] S4: The reduced material is fed into the electric furnace smelting machine 10 for heating and smelting at a temperature of 1500°C for 30 minutes. The molten iron and slag generated by the smelting are discharged from the molten iron outlet and the slag outlet respectively. The gas generated during the electric furnace smelting process is fed into the suspension heating roasting furnace 6 as a heating gas. The nickel recovery rate is 95% and the iron recovery rate is 92%.

[0066] Example 3

[0067] The comprehensive utilization system of laterite nickel ore suspension roasting-smelting in this embodiment is the same as that in Example 1.

[0068] The comprehensive utilization method of laterite nickel ore suspension roasting-smelting in this embodiment is:

[0069] The laterite nickel ore used in this embodiment contains 0.46% Ni and 58.24% Fe as main components by weight, and the feed particle size of the laterite nickel ore is p80=20 mm.

[0070] S1: First, the laterite nickel ore is fed from the feed bin 1 into the vertical grinding mill 3 and crushed to a mineral particle size of less than -2 mm. The ore powder is discharged from the cyclone separator 7 and brought into the cyclone preheater 4 through a pipeline for drying and dehydration. The preheating temperature is 200°C and the residence time is 5s.

[0071] S2: The laterite nickel ore preheated by the cyclone preheater 4 is fed into the suspension heating roasting furnace 6 through the air lock valve 5, and air and coal gas are introduced from the bottom of the suspension heating roasting furnace 6 and ignited, and the laterite nickel ore powder is in a suspended state in the furnace. The temperature in the furnace is stabilized at 1050°C, the roasting time is 5s, the volume concentration of coal gas in the suspension heating roasting furnace 6 is 20%, and the laterite nickel ore is freed of impurities such as crystal water and hydroxyl groups. The gas generated during the heating process in the suspension heating roasting furnace 6 is fed into the cyclone separator 7 for separation, and then sent to the vertical pulverizer 3 to bring the ore powder into the cyclone preheater for preheating.

[0072] S3: The material after heating and impurity removal is fed into the cyclone separator 7, and the heated gas is discharged from the upper discharge port and fed into the vertical grinding mill 3. The material is discharged from the lower discharge port and fed into the suspension reduction roaster 8. A nitrogen and coal gas mixture is introduced into the bottom of the suspension reduction roaster 8. The heat storage of the mineral itself during the heating stage is used to make the mineral react with the gas in a suspended state. The reduction temperature is controlled at 1100°C, the roasting time is 25 minutes, and the amount of coal gas introduced is based on the mass ratio of the total volume of the reducing gas in the coal gas to the laterite nickel ore powder in the suspension reduction roaster at 0.5m 3 / kg, the gas generated during the reduction process in the suspension reduction roaster 8 is discharged from the side and fed into the suspension heating roaster 6 as heating gas.

[0073] S4: The reduced material is fed into the electric furnace smelting machine 10 for heating and smelting at a temperature of 1450°C for 30 minutes. The molten iron and slag generated by the smelting are discharged from the molten iron outlet and the slag outlet respectively. The gas generated during the electric furnace smelting process is fed into the suspension heating roasting furnace 6 as a heating gas. The nickel recovery rate is 95.5%, and the iron recovery rate is 93.5%.

[0074] Example 4

[0075] The comprehensive utilization system of laterite nickel ore suspension roasting-smelting in this embodiment is the same as that in Example 1.

[0076] The comprehensive utilization method of laterite nickel ore suspension roasting-smelting in this embodiment is:

[0077] The laterite nickel ore used in this embodiment contains 1.56% Ni and 28.24% Fe as main components by weight, and the feed particle size of the laterite nickel ore is p80=20 mm.

[0078] S1: First, the laterite nickel ore is fed from the feed bin 1 into the vertical grinding mill 3 and crushed to a mineral particle size of less than -2 mm. The ore powder is discharged from the cyclone separator 7 and brought into the cyclone preheater 4 through a pipeline for drying and dehydration. The preheating temperature is 250°C and the residence time is 5s.

[0079] S2: The laterite nickel ore preheated by the cyclone preheater 4 is fed into the suspension heating roasting furnace 6 through the air lock valve 5, and air and coal gas are introduced from the bottom of the suspension heating roasting furnace 6 and ignited, and the laterite nickel ore powder is in a suspended state in the furnace. The temperature in the furnace is stabilized at 1100°C, the roasting time is 5s, the volume concentration of coal gas in the suspension heating roasting furnace 6 is 20%, and the laterite nickel ore is freed of impurities such as crystal water and hydroxyl groups. The gas generated during the heating process in the suspension heating roasting furnace 6 is fed into the cyclone separator 7 for separation, and then sent to the vertical pulverizer 3 to bring the ore powder into the cyclone preheater for preheating.

[0080] S3: The material after heating and impurity removal is fed into the cyclone separator 7, and the heated gas is discharged from the upper discharge port and fed into the vertical grinding mill 3. The material is discharged from the lower discharge port and fed into the suspension reduction roaster 8. A nitrogen and coal gas mixture is introduced into the bottom of the suspension reduction roaster 8. The heat storage of the mineral itself during the heating stage is used to make the mineral react with the gas in a suspended state. The reduction temperature is controlled at 950°C, the roasting time is 20 minutes, and the amount of coal gas introduced is 0.5m3 / s according to the mass ratio of the total volume of the reducing gas in the coal gas to the mass ratio of the laterite nickel ore powder in the suspension reduction roaster 8. 3 / kg, the gas generated during the reduction process in the suspension reduction roaster 8 is discharged from the side and fed into the suspension heating roaster 6 as heating gas.

[0081] S4: The reduced material is fed into the electric furnace smelting machine 10 for heating and smelting at a temperature of 1450°C for 30 minutes. The molten iron and slag generated by the smelting are discharged from the molten iron outlet and the slag outlet respectively. The gas generated during the electric furnace smelting process is fed into the suspension heating roasting furnace 6 as a heating gas. The nickel recovery rate is 97.2% and the iron recovery rate is 94.5%.

[0082] Example 5

[0083] The comprehensive utilization system of laterite nickel ore suspension roasting-smelting in this embodiment is the same as that in Example 1.

[0084] The comprehensive utilization method of laterite nickel ore suspension roasting-smelting in this embodiment is:

[0085] The laterite nickel ore used in this embodiment has main components of Ni 0.76% and Fe 64.18% by weight, and the feed particle size of the laterite nickel ore is p80=22 mm.

[0086] S1: First, the laterite nickel ore is fed from the feed bin 1 into the vertical grinding mill 3 and crushed to a mineral particle size of less than -2 mm. The ore powder is discharged from the cyclone separator 7 and brought into the cyclone preheater 4 through a pipeline for drying and dehydration. The preheating temperature is 200°C and the residence time is 5s.

[0087] S2: The laterite nickel ore preheated by the cyclone preheater 4 is fed into the suspension heating roasting furnace 6 through the air lock valve 5, and air and coal gas are introduced from the bottom of the suspension heating roasting furnace 6 and ignited, and the laterite nickel ore powder is in a suspended state in the furnace. The temperature in the furnace is stabilized at 1150°C, the roasting time is 5s, the volume concentration of coal gas in the suspension heating roasting furnace 6 is 35%, and the laterite nickel ore is stripped of impurities such as crystal water and hydroxyl groups. The gas generated during the heating process in the suspension heating roasting furnace 6 is fed into the cyclone separator 7 for separation, and then sent to the vertical pulverizer 3 to bring the ore powder into the cyclone preheater for preheating.

[0088] S3: The material after heating and impurity removal is fed into the cyclone separator 7, and the heated gas is discharged from the upper discharge port and fed into the vertical grinding mill 3. The material is discharged from the lower discharge port and fed into the suspension reduction roaster 8. A nitrogen and coal gas mixture is introduced into the bottom of the suspension reduction roaster 8. The mineral itself is heat stored in the heating stage, so that the mineral reacts with the gas in a suspended state. The reduction temperature is controlled at 1000°C, the roasting time is 15 minutes, and the amount of coal gas introduced is 0.5m3 / s according to the mass ratio of the total volume of the reducing gas in the coal gas to the mass ratio of the laterite nickel ore powder in the suspension reduction roaster 8. 3 / kg, the gas generated during the reduction process in the suspension reduction roaster 8 is discharged from the side and fed into the suspension heating roaster 6 as heating gas.

[0089] S4: The reduced material is fed into the electric furnace smelting machine 10 for heating and smelting at a temperature of 1450°C for 30 minutes. The molten iron and slag generated by the smelting are discharged from the molten iron outlet and the slag outlet respectively. The gas generated during the electric furnace smelting process is fed into the suspension heating roasting furnace 6 as a heating gas. The nickel recovery rate is 95.67% and the iron recovery rate is 92.5%.

[0090] Example 6

[0091] The comprehensive utilization system of laterite nickel ore suspension roasting-smelting in this embodiment is the same as that in Example 1.

[0092] The comprehensive utilization method of laterite nickel ore suspension roasting-smelting in this embodiment is:

[0093] The laterite nickel ore used in this embodiment contains 0.74% Ni and 58.24% Fe as main components by mass, and the feed particle size of the laterite nickel ore is p80=22 mm.

[0094] S1: First, the laterite nickel ore is fed from the feed bin 1 into the vertical grinding mill 3 and crushed to a mineral particle size of less than -2 mm. The ore powder is discharged from the cyclone separator 7 and brought into the cyclone preheater 4 through a pipeline for drying and dehydration. The preheating temperature is 200°C and the residence time is 5s.

[0095] S2: The laterite nickel ore preheated by the cyclone preheater 4 is fed into the suspension heating roasting furnace 6 through the air lock valve 5, and air and coal gas are introduced from the bottom of the suspension heating roasting furnace 6 and ignited, and the laterite nickel ore powder is in a suspended state in the furnace. The temperature in the furnace is stabilized at 1050°C, the roasting time is 5s, the volume concentration of coal gas in the suspension heating roasting furnace 6 is 20%, and the laterite nickel ore is freed of impurities such as crystal water and hydroxyl groups. The gas generated during the heating process in the suspension heating roasting furnace 6 is fed into the cyclone separator 7 for separation, and then sent to the vertical pulverizer 3 to bring the ore powder into the cyclone preheater for preheating.

[0096] S3: The material after heating and impurity removal is fed into the cyclone separator 7, and the heated gas is discharged from the upper discharge port and fed into the vertical grinding mill 3. The material is discharged from the lower discharge port and fed into the suspension reduction roaster 8. A nitrogen and coal gas mixture is introduced into the bottom of the suspension reduction roaster 8. The mineral itself is used to store heat during the heating stage, so that the mineral reacts with the gas in a suspended state. The reduction temperature is controlled at 1000°C, the roasting time is 20 minutes, and the amount of coal gas introduced is 0.5m3 / s according to the mass ratio of the total volume of the reducing gas in the coal gas to the mass ratio of the laterite nickel ore powder in the suspension reduction roaster 8. 3 / kg, the gas generated during the reduction process in the suspension reduction calciner 8 is discharged from the side and fed into the suspension heating calciner 6 as heating gas.

[0097] S4: The reduced material is fed into an electric furnace smelter 10 for heating and smelting at a temperature of 1450°C for 30 minutes. The molten iron and slag generated by the smelting are discharged from the molten iron outlet and the slag outlet respectively. The gas generated during the electric furnace smelting process is fed into the suspension heating roasting furnace 6 as a heating gas. The nickel recovery rate is 96.40% and the iron recovery rate is 91.23%.

[0098] Example 7

[0099] The comprehensive utilization system of laterite nickel ore suspension roasting-smelting in this embodiment is the same as that in Example 1.

[0100] The comprehensive utilization method of laterite nickel ore suspension roasting-smelting in this embodiment is:

[0101] The main components of the laterite nickel ore used in this embodiment contain Ni 1.12% and Fe 48.28% by weight, and the feed particle size of the laterite nickel ore is p80=22 mm.

[0102] S1: First, the laterite nickel ore is fed from the feed bin 1 into the vertical grinding mill 3 and crushed to a mineral particle size of less than -2 mm. The ore powder is discharged from the cyclone separator 7 and brought into the cyclone preheater 4 through a pipeline for drying and dehydration. The preheating temperature is 200°C and the residence time is 5s.

[0103] S2: The laterite nickel ore preheated by the cyclone preheater 4 is fed into the suspension heating roasting furnace 6 through the air lock valve 5, and air and coal gas are introduced from the bottom of the suspension heating roasting furnace 6 and ignited, and the laterite nickel ore powder is in a suspended state in the furnace. The temperature in the furnace is stabilized at 1050°C, the roasting time is 5s, the volume concentration of coal gas in the suspension heating roasting furnace 6 is 20%, and the laterite nickel ore is freed of impurities such as crystal water and hydroxyl groups. The gas generated during the heating process in the suspension heating roasting furnace 6 is fed into the cyclone separator 7 for separation, and then sent to the vertical pulverizer 3 to bring the ore powder into the cyclone preheater for preheating.

[0104] S3: The material after heating and impurity removal is fed into the cyclone separator 7, and the heated gas is discharged from the upper discharge port and fed into the vertical grinding mill 3. The material is discharged from the lower discharge port and fed into the suspension reduction roaster 8. A nitrogen and coal gas mixture is introduced into the bottom of the suspension reduction roaster 8. The mineral itself is used to store heat during the heating stage, so that the mineral reacts with the gas in a suspended state. The reduction temperature is controlled at 1000°C, the roasting time is 20 minutes, and the amount of coal gas introduced is 0.5m3 / s according to the mass ratio of the total volume of the reducing gas in the coal gas to the mass ratio of the laterite nickel ore powder in the suspension reduction roaster 8. 3 / kg, the gas generated during the reduction process in the suspension reduction calciner 8 is discharged from the side and fed into the suspension heating calciner 6 as heating gas.

[0105] S4: The reduced material is fed into an electric furnace smelter 10 for heating and smelting at a temperature of 1450°C for 30 minutes. The molten iron and slag generated by the smelting are discharged from the molten iron outlet and the slag outlet respectively. The gas generated during the electric furnace smelting process is fed into the suspension heating roasting furnace 6 as a heating gas. The nickel recovery rate is 96.45%, and the iron recovery rate is 93.22%.

[0106] Example 8

[0107] The comprehensive utilization system of laterite nickel ore suspension roasting-smelting in this embodiment is the same as that in Example 1.

[0108] The comprehensive utilization method of laterite nickel ore suspension roasting-smelting in this embodiment is:

[0109] The laterite nickel ore used in this embodiment has main components of Ni 0.95% and Fe 56.24% by weight, and the feed particle size of the laterite nickel ore is p80=22 mm.

[0110] S1: First, the laterite nickel ore is fed from the feed bin 1 into the vertical grinding mill 3 and crushed to a mineral particle size of less than -2 mm. The ore powder is discharged from the cyclone separator 7 and brought into the cyclone preheater 4 through a pipeline for drying and dehydration. The preheating temperature is 200°C and the residence time is 5s.

[0111] S2: The laterite nickel ore preheated by the cyclone preheater 4 is fed into the suspension heating roasting furnace 6 through the air lock valve 5, and air and coal gas are introduced from the bottom of the suspension heating roasting furnace 6 and ignited, and the laterite nickel ore powder is in a suspended state in the furnace. The temperature in the furnace is stabilized at 1050°C, the roasting time is 5s, the volume concentration of coal gas in the suspension heating roasting furnace 6 is 20%, and the laterite nickel ore is freed of impurities such as crystal water and hydroxyl groups. The gas generated during the heating process in the suspension heating roasting furnace 6 is fed into the cyclone separator 7 for separation, and then sent to the vertical pulverizer 3 to bring the ore powder into the cyclone preheater for preheating.

[0112] S3: The material after heating and impurity removal is fed into the cyclone separator 7, and the heated gas is discharged from the upper discharge port and fed into the vertical grinding mill 3. The material is discharged from the lower discharge port and fed into the suspension reduction roaster 8. A nitrogen and coal gas mixture is introduced into the bottom of the suspension reduction roaster 8. The mineral itself is used to store heat during the heating stage, so that the mineral reacts with the gas in a suspended state. The reduction temperature is controlled at 1000°C, the roasting time is 20 minutes, and the amount of coal gas introduced is 0.5m3 / s according to the mass ratio of the total volume of the reducing gas in the coal gas to the mass ratio of the laterite nickel ore powder in the suspension reduction roaster 8. 3 / kg, the gas generated during the reduction process in the suspension reduction roaster 8 is discharged from the side and fed into the suspension heating roaster 6 as heating gas.

[0113] S4: The reduced material is fed into the electric furnace smelting machine 10 for heating and smelting at a temperature of 1450°C for 30 minutes. The molten iron and slag generated by the smelting are discharged from the molten iron outlet and the slag outlet respectively. The gas generated during the electric furnace smelting process is fed into the suspension heating roasting furnace 6 as a heating gas. The nickel recovery rate is 95.2% and the iron recovery rate is 92.5%.

Claims

1. A comprehensive utilization system of laterite nickel ore suspension roasting-smelting, characterized in that: It includes feed bin, pulverizer, cyclone preheater, air lock valve, suspension heating roaster, cyclone separator, suspension reduction roaster, and smelter; The feed bin is connected to the pulverizer, the discharge port of the pulverizer is connected to the feed port of the cyclone preheater through a pipeline, the discharge port of the cyclone preheater is connected to the air lock valve, the air lock valve is connected to the suspension heating roasting furnace, the discharge port of the suspension heating roasting furnace is connected to the cyclone separator, the air outlet of the cyclone separator is connected to the air inlet of the pulverizer, the discharge port of the cyclone separator is connected to the suspension reduction roasting machine, the discharge port of the suspension reduction roasting machine is connected to the smelting machine, and the exhaust port of the smelting machine is connected to the air inlet of the suspension heating roasting furnace; The comprehensive utilization system of laterite nickel ore suspension roasting-smelting also includes a combustion station, which is arranged at the bottom of the suspension heating roasting furnace and is provided with gas and air inlets, and the combustion station is used to provide roasting heat to the suspension heating roasting furnace; and / or, a nitrogen inlet and a gas inlet are arranged in the suspension reduction roaster; the gas outlet of the suspension reduction roaster is connected to the suspension heating roaster; The suspension heating roaster, suspension reduction roaster, cyclone preheater and cyclone separator are all equipped with thermocouple temperature measuring devices and pressure sensor devices, and the temperature of each temperature measuring point and the pressure of each pressure measuring point are monitored in real time by a computer.

2. The comprehensive utilization system of laterite nickel ore suspension roasting-smelting according to claim 1, characterized in that: The laterite nickel ore suspension roasting-smelting comprehensive utilization system further comprises a feeding belt, and the feeding bin is connected to the feeding port of the grinding mill via the feeding belt; and / or the grinding mill is a vertical grinding mill.

3. The comprehensive utilization system of laterite nickel ore suspension roasting-smelting according to claim 1, characterized in that: The laterite nickel ore suspension roasting-smelting comprehensive utilization system also includes a dust collector, an induced draft fan and a chimney; The air outlet of the cyclone preheater is connected to the feed inlet of the dust collector, the air outlet of the dust collector is connected to the induced draft fan, the induced draft fan is connected to the chimney; the discharge port of the dust collector is connected to the feed inlet of the cyclone separator through a pipeline.

4. The comprehensive utilization system of laterite nickel ore suspension roasting-smelting according to claim 1, characterized in that: The smelting machine is an electric furnace smelting machine; and / or, the smelting machine is provided with a molten iron inlet and a slag inlet.

5. The method for using the comprehensive utilization system of laterite nickel ore suspension roasting-smelting according to any one of claims 1 to 4, characterized in that: The following steps are included: S1: Grinding and Dehydration First, the laterite nickel ore is fed from the feed bin into the vertical grinding mill and crushed to a mineral particle size of less than -2mm. The ore powder is carried by the gas discharged from the cyclone separator through a pipeline into the cyclone preheater for drying and dehydration. The preheating temperature is 100-300℃ and the residence time is 10-20s. S2: Suspended heating roasting The laterite nickel ore preheated by the cyclone preheater is fed into the suspension heating roaster through the air lock valve, and air and coal gas are introduced from the bottom of the suspension heating roaster and ignited at the combustion station, and the laterite nickel ore powder is in a suspended state in the suspension heating roaster; the temperature in the furnace is stabilized at 1000-1200° C., and the roasting time is 5-20 seconds. The laterite nickel ore is freed from impurities such as crystal water and hydroxyl groups to obtain a heated and impurity-removed material. The gas generated during the heating process in the suspension heating roaster is fed into a cyclone separator for separation, and then fed into a pulverizer to bring the ore powder into the cyclone preheater for preheating to obtain a heated and impurity-removed material; S3: Thermal storage reduction The heated and impurity-removed material is fed into a cyclone separator, and the heating gas is discharged from the upper gas outlet and fed into a pulverizer. The material is discharged from the lower outlet and fed into a suspension reduction roaster. A nitrogen and coal gas mixture is introduced into the bottom of the suspension reduction roaster. The mineral itself stores heat during the heating stage, so that the mineral reacts with the mixed gas in a suspended state. The reduction temperature is controlled at 800-1100°C, and the roasting time is 20-60 minutes to obtain the reduced material. The gas generated during the reduction process is discharged from the side and fed into the suspension heating roaster as heating gas. S4: Smelting The reduced material is fed into a smelting machine for heating and smelting at a temperature of 1300-1600°C for 30-50 minutes. The molten iron and slag generated by smelting are discharged from the molten iron outlet and the slag outlet respectively. The gas generated during the smelting process is fed into a suspension heating roasting furnace as a heating gas. The volume concentration of coal gas in the suspended heating roasting process is 10% to 30%; in the thermal storage reduction stage, the amount of coal gas introduced is 0.2 to 0.6 m / s according to the mass ratio of the total volume of reducing gas in the coal gas to the mass ratio of the laterite nickel ore powder in the reduction roaster. 3 / kg, the nickel-iron metallization rate reaches 60-95%; Nickel recovery rate>95%, iron recovery rate>90%.

6. The method for using the comprehensive utilization system of laterite nickel ore suspension roasting-smelting according to claim 5, characterized in that: Coal gas is one of coke oven gas, blast furnace gas, natural gas cracking gas and coal gas.

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