BaCO3基熔剂对锰铁熔体脱磷的实验研究

1 30 0℃时 ,在硅钼棒炉中采用BaCO3 BaF2 MnO2 系熔剂对 [Si]i=0 .0 84 %～ 0 .2 4 5 %的锰铁合金进行脱磷实验。结果表明 ,只要改变渣系组成和脱磷处理时间适当 ,对不同硅质量分数的锰铁合金均可获得 5 0 %以上的脱磷率。采用BaCO3 (6 0 %～ 70 % ) BaF2 (10 % ) MnO2 (2 0 %～ 30 % )渣系脱磷时 ,锰的氧化损失为负值。脱磷保锰的最佳处理时间为 10～ 15min ,脱磷过程中熔体氧位在5min内迅速上升到一定值 ,5min后氧位在很窄的范围内波动。改变渣系组成 :MnO2 从 30 %降至10 % ,BaCO3 从 6 0 %增至 80 % ,对熔剂的最大脱磷率和其对应的氧位影响不大 ,最大脱磷率为4 9.1%～ 5 6 .2 % ,对应氧位在 0 .35× 10 -6～ 0 .5 0× 10 -6之间变化。     

铁水预处理工艺、设备及操作(续)

4　铁水预处理脱磷及同时脱磷脱硫工艺4.1　同时脱磷脱硫的化学原理铁水预处理同时脱磷脱硫可用电化学反应表示如下 :阳极 :[Ｐ] 4(Ｏ2 - ) (ＰＯ3-4 ) 5ｅ阴极 :[Ｓ] 2ｅ (Ｓ2 - )图 1是竹内秀次等[4] 在 1 0 0ｔ铁水包内用固体电解质测定的喷吹ＣａＯ系熔剂进行同时脱磷脱硫处理时铁水熔池的氧位分布。得出了喷吹法同时脱磷脱硫反应的实质 :在喷枪附近 ,氧位比较高 (ＰＯ2 =1 .0 1 3× 1 0 - 9Ｐａ～ 1 .0 1 3× 1 0 - 8Ｐａ) ,进行着氧化脱磷反应 ;在铁水罐壁和顶渣与铁水界面处 ,氧位比较低 (ＰＯ2 ≤ 1 .0 1 3× 1 0 - 1 0 Ｐａ) ,进…     

铁水氧势对铁水预处理脱硅脱磷的影响

在实验室条件下,利用Ｆｅ２Ｏ３－ＣａＯ－ＣａＦ２渣系研究了在高炉铁水预处理过程中铁水氧势对脱硅、脱磷效果的影响,根据铁水的氧势分析了伴随铁水预处理脱硅过程发生的脱磷反应,研究了铁水初始硅含量对脱磷效果的作用。结果表明,在１６２３Ｋ温度和初始硅含量为０．３０％的条件下,将铁水氧势控制在（１．６４－３．２６）＊１０＾－４％范围,可获得终点硅含量为０．１４４％－０．０９０％的脱硅效果;对初始硅含量小于０．１５％的铁水,在１５７３Ｋ温度下,将铁水氧势控制在１．７＊１０＾－４％以上,可获得大于８５％的脱磷率,而在１６２３Ｋ温度下,铁水氧势高于５．５＊１０＾－４％才能获得约８０％的脱磷率,脱磷终点铁水磷含量较高。比较脱硅和脱磷过程,确认铁水脱磷预处理和最佳初硅含量为０．１０％－０．１５％。     

低碱度渣铁水预处理脱磷研究

低碱度渣铁水预处理脱磷的一个主要特点是形成高氧势、低碱度炉渣.实验选用炉渣碱度1.3～1.8,(ω)(TFe)为20%～25%,底搅强度大于0.20 m3/(min·t),对4.0%(ω)(C)-(0.1%～0.3%)(ω)(P)-0.4%(ω)(Si)的铁水进行铁水脱磷预处理.实验表明,低碱度渣能稳定获得200左右的脱磷分配比,脱磷率大于90%.同时对供氧参数和底吹强度对低碱度渣脱磷的影响进行了相应的讨论.     

预处理过程铁水中氮含量的变化

宝钢铁水预处理现场取样统计分析表明 ,高炉铁水中平均氮含量为 4 4× 10 - 6 ,进行喷粉 (石灰 氮气 )单脱硫预处理 ,铁水中平均氮含量降低 34× 10 - 6 ;若进行脱硅 脱磷 脱硫 (3脱 )预处理 ,即首先氧化脱硅 ,其次喷吹氮 +氧 +石灰基粉剂脱磷 ,最后喷吹氧 +氮 +苏打粉脱硫后可使铁水中平均氮含量降至 10×10 - 6 。提高转炉低氮铁水比 ,复吹时全程氩搅拌和降低氧气中氮含量是生产低氮钢的主要工艺措施     

本钢铁道车辆用LZ50钢车轴坯的研制

本钢采用铁水预处理、12 0t顶底复吹转炉冶炼、LF +RH TB二次精炼、4 8t钢锭 80 0轧机成坯工艺试生产了铁道车辆用LZ5 0钢 (% :0 4 7～ 0 5 5C ,0 17～ 0 4 0Si,0 6 0～ 0 90Mn) 2 30mm× 2 30mm车轴坯。LZ5 0钢材中氢含量为 (0 5～ 0 7)× 10 -6,氧 (9～ 10 )× 10 -6,氮 (5 5～ 70 )× 10 -6。A +C类非金属夹杂级别为1 0～ 2 5。LZ5 0钢 84 0℃正火处理后的机械性能为σs370～ 385MPa ,σb710～ 735MPa ,δ52 1%～ 2 3%。     

管线钢冶炼工艺的特点

介绍和分析了铁水预处理、转炉炼钢和二次精炼、连铸生产等管线钢生产工序的脱硫、脱磷、脱碳等技术 ,强调了稀土对脱氧和控制钢中夹杂的作用。该工艺冶炼出的成品管线钢的磷、硫、碳、氧、氮、氢总含量小于 92× 10 -6。     

普通热轧钢材的合理洁净度及生产工艺探讨

钢凝固前、后生成的非金属夹杂物形貌和在钢中的分布特点不同,凝固前生成的夹杂物尺寸较大,在钢中随机分布,主要影响钢材的疲劳强度和延性等性能。凝固后生成的夹杂物尺寸小,主要在晶界富集析出。硅锰脱氧钢脱氧后钢液仍含有20×10-6以上溶解氧,这部分溶解氧在钢凝固后绝大多数会转变为微细的氧化物或氧硫化物夹杂。钢凝固后生成的夹杂物主要影响钢材的冲击韧性、韧-脆转换温度等性能。 对热轧长型材用普碳钢和低合金钢不必采用铁水脱硫预处理,对热轧钢板用普碳钢可采用铁水轻度脱硫预处理,对热轧钢板用低合金高强度钢可采用铁水脱硫预处理、炼钢过程抑制回硫和出钢过程脱硫的工艺。对超低硫低合金钢,在钢水炉外精炼脱硫处理过程钢-渣间须维持非常低的氧势,炉渣成分应控制在CaO:SiO2:Al2O3=60％～65％:4％-8％:30％～35％范围。 普通热轧长型材用钢脱氧后溶解氧含量可放宽至(30-50)×10-6,对中、厚板钢溶解氧含量必须较严格控制,最好采用铝脱氧将溶解氧控制在较低的水平,并将T[O]含量控制在50×10-6以下。采用降低炼钢终点钢水氧含量、出钢挡渣、CAS和CAB等较简易炉外精炼方法和防止铸坯夹渣等措施,能够生产满足普通热轧钢洁净度要求的高品质钢材。     

本钢铁水预处理-转炉-二次精炼流程钢液硫含量控制实践

分析了本钢 15 0t高炉铁水预处理 - 15 0t转炉 -二次精炼 -连铸工艺生产的 80 0炉钢水的硫含量的变化。通过喷CaO粉和加Mg粉高效脱硫的铁水预处理能将铁水中平均硫含量从 35 0× 10 -6脱至 5 0×10 -6。在转炉冶炼中 ,因加入含硫废钢和石灰以及精炼前钢水带有少量转炉渣 ,使成品钢水硫含量增至 15 0×10 -6。研究和分析了铁水预处理时 ,石灰喷入量和Mg粉加入量对铁水脱硫的影响。     

超低碳奥氏体不锈钢00Cr18Ni10还原脱磷研究

在 2 5kg真空感应炉上用镁钙合金对超低碳奥氏体不锈钢 0 0Cr18Ni10进行了还原脱磷试验。通过充入工业纯氩使炉内压力为 6 6 .6 6kPa和精炼时的反应温度 14 5 0～ 15 0 0℃ ,加入镁钙合金 5 0kg t和助熔剂CaF2 11kg t,可使精炼后 0 0Cr18Ni10的磷含量进一步降低到 (5 0～ 6 0 )× 10 - 6 ,钢中氧、硫含量分别稳定降到(4～ 6 )× 10 - 6 和 15× 10 - 6 。     

熔炼次数对M17返回料合金成分、组织和性能的影响

实验结果表明,M17铸造高温合金(%:0.16C、8.79Cr、5.79A1、4.93Ti、3.29Mo、15.20Co、0.78V、0.015B、0.073Zr、0.002S、0.001P、0.001 1O、0.001 0N)经25 kg真空感应炉返回重熔后,Si含量随重熔次数的增加而略有增加,合金中主要元素和其它杂质元素S、P、H的含量变化不大,而氧、氮略有增加;合金中初生碳化物由新合金中的草书体逐渐向返回合金块状转变,初生碳化物的遗传性堵塞合金凝固时的补缩通道,使返回料合金的疏松倾向增大,高温塑性下降较大。     

China's Major Non-ferrous Metals Imports & Exports

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Zinc Production by Province in 2014

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80% of Chinese Firms Purchasing Overseas Mines Ended up in the Red

<正>Minmetals Resources acquired the world’s largest copper mine under construction for USD5.85 billion.One after another,listed companies Jien Nickle,China Molybdenum and Chihong Zinc and Germanium raised money to get involved in overseas mining projects…SOEs and private enterprises are engaged in a frenzy of overseas mine purchasing.A reporter with Economic     

Copper Processing Profit Dropped Sharply,Copper Consumption Will Face Impact in the Second Half of the Year

正Judging from China’s copper consumption field,the biggest consumption unit is electric power,which accounts for 47%of total consumption;it is followed by light industry sector,including household electrical appliance,machinery,durable goods and hardware etc,which accounts for 22%of total consumption;followed by transportation field,     

Central Geological Prospecting Fund Newly Added 16.47 Million Tonnes of Bauxite in 2013

正In 2013,the Central Geological Prospecting Fund(CGPF)Project newly discovered 15 ore fields,including 3 large above ore fields,and 5medium sized ore fields.The reporter learned from the recently published"Annual Report of Central Geological Prospecting Fund Project(2013)"that,from 2006 to 2013 the CGPF     

Manufacturers of Copper Tube for Central Air Conditioner Use Face Mounting Pressure in the Final Quarter of the Year

正This year,the investment growth rate of real estate industry continued to slow down,sold area of commercial housing also dropped significantly,which brought huge pressure to the domestic air conditioning manufactures.In the first half of the year,by relying on high growth in national financial expenditure,along with investment in public infrastructure     

Xinjiang Ranks No.1 in Production of Primary Aluminum in China

正Kang Yi,Honorary Chairman of China Nonferrous Metals Industry Association,said recently at the Forum on Development of the Non-ferrous Metals Industry in Central and Western China held in Zhengzhou that,as more and more electrolytic aluminum factories in Xinjiang came into operation,the electrolytic aluminum output of Xinjiang had reached2,275,000 tons in the first 7 months this year,     

Shenhuo Coal Industry and Electricity Power Completed800,000 t/a Aluminum Project in Xinjiang

正"Xinjiang project has been completed according to schedule,but total completion and total start of production are two different concepts,after completion it still needs a gradual process of reaching production target."On the morning of November 3,Shenhuo Coal Industry and Electricity Power told investors the above statement on the investor interaction platform.     

Guangdong Metal Transaction Center has Become the Second Largest Precious Metal Transaction Platform Nationwide

正The reporter learned from Guangdong Province Precious Metal Transaction Center that in 2013the Center maintained healthy development momentum,and had become the second largest precious metal transaction platform in China in terms of market size;currently Guangdong is quickening steps of financial innovation for the Center,aiming to build a transaction center with international core competitiveness.