ABSTRACT Siderite ore (FeCO3) is an important iron ore resource that is widely distributed around the world. However, it is difficult to process using conventional methods owing to the low iron grade, easy sliming, and high impurity content. Based on the mechanism of thermal decomposition, the combination of metallurgy and processing is a promising …
With the optimal roasting conditions, comprising a feeding rate of 100 kg/h, roasting temperature of 520 °C, and a mixed gas composed of a CO reducing gas and N 2 fluidizing gas at flow rate of 4.0 Nm 3 /h and 2.0 Nm 3 /h, respectively, an iron concentrate containing 60.18% Fe with an iron recovery of 90.17% would be achieved after staged ...
During the roasting process, siderite (FeCO3) transforms to magnetite (Fe3O4) along with producing carbon monoxide (CO), but hematite (Fe2O3) needs CO to reduce into magnetite. The process of ...
During the roasting process, siderite (FeCO3) transforms to magnetite (Fe3O4) along with producing carbon monoxide (CO), but hematite (Fe2O3) needs CO to reduce into magnetite. The process of ...
Experiments were conducted using a conveyor bed magnetization roasting process (CBMRP) to investigate the magnetization of siderite. Multi-stage magnetic separation processes were adopted to ...
Fluidized magnetization roasting is the proper process for refractory siderite resource; it is of great significance to enhance the competitiveness of domestic iron ore concentrate and ensure the safety of China's iron ore supply. ... The roasted ore structure of siderite after magnetization roasting was relatively loose, which was …
The fluidization roasting process rapidly converted siderite to ferromagnetic magnetite, with the magnetite distributed on particle surfaces and internal cracks. CO 2 …
The roasting of siderite (FeCO 3) was investigated to clarify the reaction mechanism in inert atmosphere using micro fluidized bed reaction analyzer coupled with on-line particle sampling (MFBRA-P).Thermodynamic results indicated that the reactions of 6FeO + CO 2 → C + 2Fe 3 O 4 and 3FeO + CO → C + Fe 3 O 4 are both possible to …
In order to develop limonite and decrease CO2 emissions, siderite is proposed as a clean reductant for suspension magnetization roasting (SMR) of limonite. An iron concentrate (iron grade: 65.92wt%, iron recovery: 98.54wt%) was obtained by magnetic separation under the optimum SMR conditions: siderite dosage 40wt%, roasting …
Magnetization roasting is one of the most effective way of utilizing low-grade refractory iron ore. However, the reduction roasting of siderite (FeCO 3) generates weakly magnetic wüstite, thus reducing iron recovery via weak magnetic separation.We systematically studied and proposed the fluidized preoxidation-low-temperature …
In this process, the utilization of siderite suffers from the intense CO 2 emissions and resulting in serious environmental impacts, which violates the increasingly rigorous regulations on carbon emission control. Therefore, a low-carbon and environmentally friendly roasting and reduction route is highly desirable for the siderite …
The roasting process has two stages: the oolitic hematite is first preheated at 1050 °C for 2 min, and then roasted at 650 °C for 5 min with 30% CO content. ... After linear fitting, the most probable mechanism of siderite suspension roasting is the sphere shrinkage model R3, and the restrictive link is controlled by a chemical reaction.
During the roasting process, siderite (FeCO3) transforms to magnetite (Fe3O4) along with producing carbon monoxide (CO), but hematite (Fe2O3) needs CO to reduce into magnetite. The process of ...
Microwave roasting of siderite at 800 °C with different holding times and the catalytic combustion effects on anthracite are investigated.The heating rate curves indicate that siderite can be heated in microwave field, and the heating rate increases considerably when FeCO 3 almost decomposes and oxidizes to Fe 3 O 4 and Fe 2 O 3.The …
The process of simultaneously roasting and magnetic separation was developed to treat the low grade siderite and hematite ores without adding any …
The conveyor bed magnetization roasting process (CBMRP, also known as suspension roasting) is a process that has been recently developed for the magnetization roasting of siderite employing micron-sized powder as a raw material that has been fully magnetized via roasting at 600–800 °C for 3–10 s under a reducing atmosphere.
The fluidization roasting process rapidly converted siderite to ferromagnetic magnetite, with the magnetite distributed on particle surfaces and internal cracks. CO 2 was used during roasting to facilitate the transformation of siderite to magnetite. The iron recovery reached more than 98 % when the roasting time was only 2 min for sample …
The non-isothermal magnetization roasting process and isothermal magnetization roasting process of siderite ore were investigated using thermogravimetric (TG) analysis and a real-time infrared gas ...
Microwave roasting of siderite at 800 °C with different holding times and the catalytic combustion effects on anthracite are investigated.The heating rate curves indicate that siderite can be heated in microwave field, and the heating rate increases considerably when FeCO 3 almost decomposes and oxidizes to Fe 3 O 4 and Fe 2 O …
In this paper, a process of pre-oxidation and magnetization roasting followed by low-intensity magnetic separation and acid leaching (OMLA) was developed to …
Abstract. During the roasting process, siderite (FeCO 3) transforms to magnetite (Fe 3 O 4) along with producing carbon monoxide (CO), but hematite (Fe 2 O 3) needs CO to reduce into magnetite.The process of simultaneously roasting and magnetic separation was developed to treat the low grade siderite and hematite ores …
The fluidization roasting process rapidly converted siderite to ferromagnetic magnetite, with the magnetite distributed on particle surfaces and internal cracks. CO 2 was used during roasting to facilitate the transformation of siderite to magnetite. The iron recovery reached more than 98 % when the roasting time was only …
2.2. Methods. The natural siderite (FeCO 3) used as a reductant in the magnetization roasting process was mainly attributed to the carbon monoxide (CO) that occurred in the thermal decomposition process.Much research has been conducted on the thermal stability of siderite, and the two-step decomposition mechanism in a neutral …
Based on the mechanism of thermal decomposition, the combination of metallurgy and processing is a promising method to process siderite ore. In this study, …
In this paper, both low-grade refractory siderite-containing iron ore and high-grade single siderite phase iron ore are taken as experimental objects to systematically …
After magnetization roasting, the weakly magnetic iron minerals, including hematite, limonite and siderite, are selectively reduced or oxidized to ferromagnetic magnetite, which is relatively ...
magnetization roasting process, hematite and siderite were suc-cessfully transformed into mag netite or maghemite, which. enhanced the magnetism of the iron minerals (Zhang et al.
taining refractory siderite and hematite. This process has wide applicability because it is unlimited by the proportion of siderite and hematite in iron ore and can avoid the roasting of siderite into wüstite. In particular, the behavior and path of siderite phase transformation during oxidation and reduction were investigated. 2. Experimental
Siderite, as an abundant iron ore, has not been effectively utilized, with a low utilization rate. In this study, the in-situ kinetics and mechanism of siderite during suspension magnetization roasting (SMR) were investigated to improve the selective conversion of siderite to magnetite and CO, enriching the theoretical system of green …
The reaction of hematite and siderite in magnetization roasting process are shown in Equation (2), Equations (3), (4), respectively. When the siderite was used as a reductant in magnetization roasting, the main reaction equation is shown in Equation (5). According to the reaction equations, we can see that the alternative reductant of siderite ...
The non-isothermal magnetization roasting process and isothermal magnetization roasting process of siderite ore were investigated using …
In this work, the beneficiation of siderite fines containing high levels of carbonates was studied using a combined fluidized-bed magnetizing roasting process. The siderite was almost completely converted into magnetite under the optimum conditions of preheating at 550 °C for 30 s followed by magnetizing roasting at 550 °C for 60 s at …
magnetization roasting process to roast the mixed samples of the siderite and hematite, achieving efficient recovery of iron minerals. And the reaction mechanism of self-magnetization roasting was studied (Figure 1) [18]. The suspension self-magnetization roasting provides a new way for the efficient and clean utilization of siderite ore.
The resources of siderite are abundant in China, rotary kiln process is the mainstream technology of domestic baking industry at present, it has already realized industrial production in the field of magnetization roasting of siderite. But this method is prone to accretion, affecting the production rate, and has high energy consumption and ...
In the present study, a green magnetization roasting process was proposed by using siderite (FeCO 3) as the reductant.The influences of the siderite dosage, roasting temperature and roasting time on the magnetization roasting process were investigated. The saturation magnetization of roasted samples was analyzed by a …
The fluidization roasting process rapidly converted siderite to ferromagnetic magnetite, with the magnetite distributed on particle surfaces and internal cracks. CO 2 was used during roasting to facilitate the transformation of siderite to magnetite. The iron recovery reached more than 98 % when the roasting time was only 2 min for sample …
In this paper, a process of pre-oxidation and magnetization roasting followed by low-intensity magnetic separation and acid leaching (OMLA) was developed to separate and recover iron from siderite ...
