CN-122012917-A - Sintering binder for high-proportion concentrates and preparation and use methods thereof

CN122012917ACN 122012917 ACN122012917 ACN 122012917ACN-122012917-A

Abstract

The sintering binder for the high-proportion concentrates comprises, by weight, 88-93 parts of high-activity MgO (dry basis), 3-7 parts of steel oil-containing sludge, 3-6 parts of rare earth tailings and 0.5-1 part of guar gum. And the sintering binder prepared from the raw materials is used for sintering high-proportion concentrate. The invention prepares high-activity MgO powder by using magnesite tailings, can react with water to form Mg (OH) 2 , increases the bonding effect of a binder, and simultaneously recycles the magnesite tailings. 2) The cohesiveness of organic matters in the steel oily sludge is fully utilized, meanwhile, the addition amount of sintered polymer organic matters (guar gum) can be reduced, the manufacturing cost of the binder is reduced, and the treatment cost of the oily sludge is saved. According to the invention, the proportion of the sintering binder is adjusted according to the differentiation of the balling performance of the iron concentrate, the using amount of the binder is saved, the air permeability of the whole material layer is improved, and the high-proportion concentrate sintering technical index is further improved.

Inventors

LI JINLIAN
HAN ZIWEN
WANG LIANG
LI XIANG
DUAN LIXIANG
LIU SHUAI
JIN JIN
LIU YANG

Assignees

鞍钢股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260206

Claims (4)

1. The sintering binder for the high-proportion concentrate is characterized by comprising, by weight, 88-93 parts of high-activity MgO, 3-7 parts of steel oil-containing sludge, 3-6 parts of rare earth tailings and 0.5-1 part of guar gum.
2. The high ratio sintered binder for concentrates as claimed in claim 1, wherein the viscosity of 2% aqueous solution of guar is greater than 20000pas.
3. A method for preparing the high-proportion sintered binder for concentrates as claimed in claim 1, comprising the following method steps: S1, roasting magnesite tailings at a medium temperature of 650-750 ℃ for 20-40 min to obtain high-activity MgO, and crushing and grinding the high-activity MgO into powder; S2, mixing the steel oil-containing sludge and the rare earth tailings in an aqueous medium for reaction, and then carrying out solid-liquid separation, and drying a solid product to form an organic-inorganic complex; S3, mixing and grinding the high-activity MgO powder, the organic-inorganic complex and the guar gum according to the proportion to prepare powder, so as to form the high-proportion sintered adhesive for the fine ore, wherein the particles with the granularity composition of less than 0.074mm account for more than 95%.
4. A method of using the sintered binder for high proportion concentrates as claimed in claim 1, comprising the steps of: 1) The method comprises the steps of forming a mixture A from 76-85 parts by weight of iron concentrate, 3-7 parts by weight of binder, 3-7 parts by weight of fuel and 7-11 parts by weight of alkaline flux, wherein the sphericity index K of the iron concentrate is less than 0.2; 2) The method comprises the steps of forming a mixture B from 81-87 parts by weight of iron concentrate, 3-5 parts by weight of binder, 3-6 parts by weight of fuel and 6-9 parts by weight of alkaline flux, wherein the iron concentrate has a sphericity index K=0.2-0.35; 3) The method comprises the steps of forming an iron concentrate with a balling index K of more than 0.35, a binder, fuel and an alkaline flux into a mixture C, wherein the mixture C comprises, by weight, 83-87 parts of the iron concentrate, 1-3 parts of the binder, 2-5 parts of the fuel and 5-10 parts of the alkaline flux; 4) When the mass fraction of the iron concentrate is less than or equal to 70% and less than 80%, 30-50 parts of mixture A, 21-45 parts of mixture B, 15-26 parts of mixture C, 25-45 parts of mixture A, 25-46 parts of mixture B, 20-30 parts of mixture C, 20-30 parts of mixture A, 30-50 parts of mixture B and 25-41 parts of mixture C; 5) Mixing the mixture A, the mixture B and the mixture C in a mixer according to the proportion in the step 4), wherein the mixing time is 3-5 min, adding the sintered mixture cloth onto a sintering trolley, igniting, exhausting and sintering to obtain the finished product of the sintered ore.

Description

Sintering binder for high-proportion concentrates and preparation and use methods thereof Technical Field The invention belongs to the technical field of sintering, and particularly relates to a high-proportion sintering binder for a concentrate and a preparation method and a use method thereof. Background Magnetite concentrates are very fine in size, typically below 150 μm. When the iron-containing raw materials in the sintered mixture are magnetite concentrates or the magnetite concentrate is relatively high, the quantity of the sticky powder is too large, and serious negative effects can be generated on the granulating performance and the air permeability of the material layer. In addition, a large amount of magnetite concentrate is coated in the adhesion layer of the granulated particles and is difficult to oxidize, unoxidized magnetite concentrate is generally low in reactivity in the sintering process, and more fuel and higher sintering temperature are required to form enough sintering liquid phase, so that the strength of the sintering ore is ensured. Sinter production is directly related to the vertical sintering rate, which is largely dependent on the permeability of the layers of the sintering process. The air permeability of the raw material layer is improved, and the damage of the dry belt granulating pellets in the sintering process is reduced, so that the air permeability in the sintering process can be improved. Therefore, strengthening the iron ore pelletization process and improving the thermal stability of the pelletization pellets are one of the important actions for improving the air permeability of the material layer. Binders currently used for iron ore agglomeration can be divided into two broad categories, inorganic and organic binders. Inorganic binders such as bentonite, water glass, quicklime, and the like. The quicklime and bentonite are the most widely applied, the quicklime plays a double role of a flux and a binder in sintering, and the quicklime is in extremely fine colloid particles after digestion, has a large specific surface area, and can adsorb and hold a large amount of water, so that the granulating effect is improved. However, the presence of incompletely digested quicklime particles in the granulated pellets, further digestion of the volume during the sinter drying process will expand more than one time, so that the pellets are broken to produce powder, affecting the gas permeability during the sinter process. Bentonite has poor bonding effect due to ion exchange caused by the existence of a large amount of calcium and magnesium ions in the alkaline environment of sintering. The organic binder has the defects of small addition amount and difficult uniform mixing, and has higher mechanical strength at normal temperature, but the organic matters are decomposed prematurely at high temperature to deteriorate the thermal stability of the granulated pellets and cannot withstand the thermal shock in the high temperature process. Disclosure of Invention The invention aims to provide a sintering binder for high-proportion concentrate and a preparation and application method thereof, wherein high-activity MgO prepared from magnesite is used as a magnesium-based material, steel oily sludge is used as an iron-based material, and high-molecular organic matters are added as auxiliary materials to prepare the binder for high-proportion concentrate sintering, so that the balling performance of iron concentrate is improved, the air permeability of a sinter bed is improved, and the sintering production efficiency and the quality of sinter are improved. In order to achieve the above purpose, the invention is realized by adopting the following technical scheme: The sintering binder for the high-proportion concentrate comprises, by weight, 88-93 parts of high-activity MgO, 3-7 parts of steel oil-containing sludge, 3-6 parts of rare earth tailings and 0.5-1 part of guar gum. Further, the viscosity of the 2% aqueous solution of guar gum is greater than 20000pas. The preparation method of the sintering binder for the high-proportion concentrate comprises the following method steps: S1, roasting magnesite tailings at a medium temperature of 650-750 ℃ for 20-40 min to obtain high-activity MgO, and crushing and grinding the high-activity MgO into powder; s2, mixing the steel oil-containing sludge and the rare earth tailings in an aqueous medium for reaction, and then carrying out solid-liquid separation, and drying a solid product to form an organic/inorganic complex; s3, mixing and grinding the high-activity MgO powder, the organic-or inorganic complex and the guar gum according to the proportion to prepare powder, so as to form the high-proportion sintered adhesive for the fine ore, wherein the particles with the granularity composition of less than 0.074mm account for more than 95%. The application method of the sintering binder for the high-proportion concentrate, wherein the high-proportio