阅读说明：本技术 电炉炼钢用造渣剂及其制造方法 (Slag former for electric furnace steelmaking and manufacturing method thereof ) 是由 陈荣欢 施允 王如意 柳向椿 于 2019-01-15 设计创作，主要内容包括：本发明公开了一种电炉炼钢用造渣剂及其制造方法,该造渣剂包括以下重量配比的原料：硅钢酸性污泥60-80%、用后镁碳砖10-25%、粘结剂5-10%、镁砂0-15%和碳粉0-15%。该制造方法包括步骤1：冷轧酸性废水处理后产生的硅钢酸性污泥经脱水处理,备用；步骤2：拆解下来的用后镁碳砖经破碎处理,备用；步骤3：把60-80%的硅钢酸性污泥、10-25%的用后镁碳砖、5-10%的粘结剂、0-15%的镁砂和0-15%的碳粉投入混料机充分混合均匀；步骤4：把混合均匀的料经压球机压制后经自然脱水或烘烤脱水,形成造渣剂。本发明将硅钢酸性污泥加工成炼钢必须的造渣剂产品,能替代部分轻烧白云石等炼钢用原材料。(The invention discloses a slag former for electric furnace steelmaking and a manufacturing method thereof, wherein the slag former comprises the following raw materials in parts by weight: 60-80% of silicon steel acid sludge, 10-25% of used magnesia carbon brick, 5-10% of binder, 0-15% of magnesia and 0-15% of carbon powder. The manufacturing method comprises the following steps of 1: dehydrating the silicon steel acid sludge generated after the cold rolling acid wastewater treatment for later use; step 2: crushing the disassembled used magnesia carbon brick for later use; and step 3: putting 60-80% of silicon steel acid sludge, 10-25% of used magnesia carbon brick, 5-10% of binder, 0-15% of magnesia and 0-15% of carbon powder into a mixer for fully and uniformly mixing; and 4, step 4: and pressing the uniformly mixed materials by a ball press, and then dehydrating by natural dehydration or baking to form the slag former. The invention processes the silicon steel acid sludge into the slag former product necessary for steelmaking, and can replace part of the raw materials for steelmaking such as light burned dolomite and the like.)

1. A slag former for electric furnace steelmaking is characterized in that: comprises the following raw materials in parts by weight: 60-80% of silicon steel acid sludge, 10-25% of used magnesia carbon brick, 5-10% of binder, 0-15% of magnesia and 0-15% of carbon powder.

2. The slag former for electric steelmaking according to claim 1, wherein: the silicon steel acid sludge mainly comprises the following components in parts by weight: 15-28% of CaO and 5-10% of SiO₂10-25% of MgO, 15-25% of T.Fe and 10-17% of Al₂O₃3-6% of T.C, no more than 5% of impurities and no more than 1% of Cl.

3. The slag former for electric steelmaking according to claim 2, wherein: the impurities include P₂O₅And S.

4. The slag former for electric steelmaking according to claim 1, wherein: the used magnesia carbon brick comprises 70-90% of MgO and 10-30% of C.

5. The slag former for electric steelmaking according to claim 1, wherein: the binder comprises one or more of cement clinker, chemical dextrin, water glass and flour.

6. A method for producing the slag forming agent for electric steelmaking according to any one of claims 1 to 5, characterized by comprising: the method comprises the following steps:

step 1: dehydrating the silicon steel acid sludge generated after the cold rolling acid wastewater treatment for later use;

step 2: crushing the disassembled used magnesia carbon brick for later use;

and step 3: putting 60-80% of silicon steel acid sludge, 10-25% of used magnesia carbon brick, 5-10% of binder, 0-15% of magnesia and 0-15% of carbon powder into a mixer for fully and uniformly mixing;

and 4, step 4: and pressing the uniformly mixed materials by a ball press, and then dehydrating by natural dehydration or baking to form the slag former.

7. The method for producing a slag forming agent for electric steelmaking according to claim 6, wherein: in the step 1, the water content of the silicon steel acid sludge subjected to dehydration treatment is less than 10%.

8. The method for producing a slag forming agent for electric steelmaking according to claim 6, wherein: in the step 2, the particle size of the crushed used magnesia carbon brick is less than 0.3 mm.

9. The method for producing a slag forming agent for electric steelmaking according to claim 6, wherein: in the step 4, the size of the slagging agent is 30-60mm, and the water content of the slagging agent is less than 3%.

10. The method for producing a slag forming agent for electric steelmaking according to claim 6, wherein: during electric furnace smelting, the slag former is added into the electric furnace through a bin or a material basket to replace light-burned dolomite.

Technical Field

The invention relates to solid waste of metallurgical enterprises and a treatment method thereof, in particular to a slagging agent for electric furnace steelmaking and a manufacturing method thereof.

Background

A large amount of acid sludge is generated after the acid wastewater generated by the silicon steel cold rolling and pickling process is treated, the main components of the acid sludge generated after the pickling wastewater treatment are oxides of calcium, magnesium, aluminum and iron, and the main chemical compositions are shown in a table 1:

table 1: main chemical composition of cold-rolled acid sludge, (wt%)

CaO

SiO2

Al2O3

MgO

T.Fe

S

P2O5

Cl

T.C

15~28

5~10

8~17

10~25

15~25

0.1~1.0

0.1~2.0

0.1~1.0

1.0~5.0

At present, the treatment mode of the acid sludge is mainly to pay and seek the cooperative treatment of a cement enterprise, but the treatment and the utilization of the cement enterprise have great difficulty due to the complex sludge component and certain magnesium content. In addition, with the improvement of environmental requirements, the outward transportation treatment and disposal of the sludge are more and more difficult, so that the approaches are less and less, and the cost is higher and higher.

In the process of electric furnace steelmaking, in order to remove impurities such as sulfur, phosphorus and the like in molten steel, carry out molten steel heat preservation, protect a furnace lining, prevent molten steel from being oxidized again and the like, slagging agent materials such as lime, light burned dolomite and the like are required to be added for smelting. The slag former product necessary for steel smelting is developed by utilizing metallurgical solid waste resources, and the method mainly focuses on the aspect of steelmaking dust and mud. The main component of the steelmaking dust mud is iron oxide, the content of total iron (T.Fe) is generally more than 40 percent, and the steelmaking dust mud is used for developing slag former products, can effectively reduce the cost and recover metallurgical solid waste resources. The total iron content of the acid sludge generated after the silicon steel pickling wastewater is treated is generally less than 25%, and the acid sludge is mainly treated by outsourcing at present and has higher cost.

In the process of steel production, refractory materials are indispensable. How to effectively treat and utilize a large amount of used refractory materials disassembled from steel ladles, steel furnaces and the like after the service lives of the steel ladles, the steel furnaces and the like. After the disassembled used refractory materials are selected, part of the disassembled used refractory materials are recycled with good quality, and most of the rest refractory materials are used for pit filling and burying of the capital construction project, so that good disposal and utilization values are not realized.

The Chinese patent CN1083892C discloses a method for producing a steelmaking slag former by using steelmaking converter sludge, which comprises the steps of mixing steelmaking converter dedusting sludge with fuel and additives, uniformly mixing, extruding to prepare a green brick, drying the green brick, sintering by using a wheel kiln or a tunnel kiln, crushing and screening to prepare steelmaking composite slag.

The Chinese invention patent CN101413042B discloses that the slag former with fast slag formation is produced by using the steel-making sludge as the main raw material; the slagging agent of the patent is composed of the following raw materials in parts by weight: 25-35% of steelmaking sludge, 25% of high-siliceous manganese ore, 35-45% of quartz sand and 5% of magnesium chloride.

The invention discloses a slag former for converter steelmaking and a preparation method thereof in Chinese patent CN103131818B, which mainly utilizes converter sludge and steel rolling iron scale, and the slag former comprises the following components in percentage by mass: 50-55% of converter sludge, 35-45% of steel rolling iron scale and 5-10% of adhesive.

The invention of Chinese patent application CN106277705A discloses a method for directly returning sludge containing chromium, nickel and the like generated in the production process of stainless steel to stainless steel smelting treatment and utilization after dehydration and drying.

The main components of the converter steelmaking sludge are Fe2O3, FeO, CaO and the like, and the raw materials such as manganese ore, dolomite, quartz sand and the like are mostly required to be added when the converter steelmaking sludge is used as a slagging agent, so that the recycling cost is increased; the corrosion of smelting facilities caused by the direct return of the chromium-nickel containing stainless steel sludge to steel production is increased, the service life of the facilities is influenced for a long time, and the chromium-nickel containing stainless steel sludge and the silicon steel acid sludge are two types of solid wastes.

Disclosure of Invention

The invention aims to provide a slagging agent for electric furnace steelmaking and a manufacturing method thereof, which are used for processing silicon steel acid sludge into a slagging agent product necessary for steelmaking and can replace part of raw materials for steelmaking such as light burned dolomite and the like.

The invention is realized by the following steps:

a slag former for electric furnace steelmaking comprises the following raw materials in parts by weight: 60-80% of silicon steel acid sludge, 10-25% of used magnesia carbon brick, 5-10% of binder, 0-15% of magnesia and 0-15% of carbon powder.

The silicon steel acid sludge mainly comprises the following components in parts by weight: 15-28% of CaO and 5-10% of SiO₂10-25% of MgO, 15-25% of T.Fe and 10-17% of Al₂O₃3-6% of T.C, no more than 5% of impurities and no more than 1% of Cl.

The impurities include P₂O₅And S.

The used magnesia carbon brick comprises 70-90% of MgO and 10-30% of C.

The binder comprises one or more of cement clinker, chemical dextrin, water glass and flour.

A method for manufacturing a slag forming agent for electric furnace steelmaking comprises the following steps:

step 1: dehydrating the silicon steel acid sludge generated after the cold rolling acid wastewater treatment for later use;

step 2: crushing the disassembled used magnesia carbon brick for later use;

and step 3: putting 60-80% of silicon steel acid sludge, 10-25% of used magnesia carbon brick, 5-10% of binder, 0-15% of magnesia and 0-15% of carbon powder into a mixer for fully and uniformly mixing;

and 4, step 4: and pressing the uniformly mixed materials by a ball press, and then dehydrating by natural dehydration or baking to form the slag former.

In the step 1, the water content of the silicon steel acid sludge subjected to dehydration treatment is less than 10%.

In the step 2, the particle size of the crushed used magnesia carbon brick is less than 0.3 mm.

In the step 4, the size of the slagging agent is 30-60mm, and the water content of the slagging agent is less than 3%.

During electric furnace smelting, the slag former is added into the electric furnace through a bin or a material basket to replace light-burned dolomite.

Compared with the prior art, the invention has the following beneficial effects:

1. according to the invention, the silicon steel acid sludge is processed into a slag former product necessary for steelmaking, so that the total amount of the deputy disposal of the solid wastes of enterprises is reduced, the environmental event risk of the deputy disposal of the silicon steel acid sludge is eliminated, and a large amount of deputy disposal cost is saved.

2. The slagging agent prepared by the invention can replace part of the raw materials for steelmaking such as light burned dolomite and the like, and saves the consumption of the steelmaking raw materials such as dolomite and the like.

3. The silicon steel acid sludge adopted by the invention contains about 20 percent of FeO, is beneficial to the balance of smelting slag system interphase, inhibits the amount of elementary iron in molten steel entering slag phase, and indirectly improves the yield of metal.

4. The method has the advantages of simple process, convenient operation, low cost and good environmental and economic benefits.

Detailed Description

A slag former for electric furnace steelmaking comprises the following raw materials in parts by weight: 60-80% of silicon steel acid sludge, 10-25% of used magnesia carbon brick, 5-10% of binder, 0-15% of magnesia and 0-15% of carbon powder.

The silicon steel acid sludge mainly comprises the following components in parts by weight: 15-28% of CaO and 5-10% of SiO₂10-25% of MgO, 15-25% of T.Fe (total iron), 10-17% of Al₂O₃3-6% of T.C, no more than 5% of impurities and no more than 1% of Cl. The impurities include P₂O₅And S.

The used magnesia carbon brick comprises 70-90% of MgO and 10-30% of C.

The binder comprises one or more of raw materials such as cement clinker, chemical dextrin (CMC), water glass, flour and the like.

A method for manufacturing a slag forming agent for electric furnace steelmaking comprises the following steps:

step 1: and dehydrating the silicon steel acid sludge generated after the cold rolling acid wastewater treatment for later use. Preferably, the water content of the dehydrated silicon steel acid sludge is less than 10%.

Step 2: and crushing the disassembled used magnesia carbon brick for later use. Preferably, the particle size of the crushed used magnesia carbon brick is less than 0.3 mm.

And step 3: 60-80% of silicon steel acid sludge, 10-25% of used magnesia carbon brick, 5-10% of binder, 0-15% of magnesia and 0-15% of carbon powder are put into a mixer to be fully and uniformly mixed.

And 4, step 4: and pressing the uniformly mixed materials by a ball press, and then dehydrating by natural dehydration or baking to form the slag former. Preferably, the size of the slagging agent is 30-60mm, and the water content of the slagging agent is less than 3%.

During electric furnace smelting, the slag former produced in the above steps is added into an electric furnace through a bunker or a material basket, and can replace 50-100% of light-burned dolomite for use according to smelting varieties.