CN110170646B - 超细铁粉及其生产方法 - Google Patents
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- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 title claims abstract description 95
- 238000004519 manufacturing process Methods 0.000 title claims description 10
- 229910052742 iron Inorganic materials 0.000 claims abstract description 25
- 230000005484 gravity Effects 0.000 claims abstract description 8
- 239000002245 particle Substances 0.000 claims description 30
- 239000002699 waste material Substances 0.000 claims description 15
- 238000005406 washing Methods 0.000 claims description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 10
- 239000000843 powder Substances 0.000 claims description 9
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 4
- 239000002131 composite material Substances 0.000 claims description 4
- 229910052739 hydrogen Inorganic materials 0.000 claims description 4
- 239000001257 hydrogen Substances 0.000 claims description 4
- 238000002360 preparation method Methods 0.000 claims description 4
- 238000003825 pressing Methods 0.000 claims description 4
- 238000012545 processing Methods 0.000 claims description 4
- 238000000034 method Methods 0.000 claims description 2
- 239000010814 metallic waste Substances 0.000 abstract description 2
- 238000011085 pressure filtration Methods 0.000 description 4
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 3
- 230000001186 cumulative effect Effects 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 238000004663 powder metallurgy Methods 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 239000003814 drug Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000696 magnetic material Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000005272 metallurgy Methods 0.000 description 2
- KMUONIBRACKNSN-UHFFFAOYSA-N potassium dichromate Chemical compound [K+].[K+].[O-][Cr](=O)(=O)O[Cr]([O-])(=O)=O KMUONIBRACKNSN-UHFFFAOYSA-N 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 235000010575 Pueraria lobata Nutrition 0.000 description 1
- 241000219781 Pueraria montana var. lobata Species 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- 239000011362 coarse particle Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 229910000365 copper sulfate Inorganic materials 0.000 description 1
- ARUVKPQLZAKDPS-UHFFFAOYSA-L copper(II) sulfate Chemical compound [Cu+2].[O-][S+2]([O-])([O-])[O-] ARUVKPQLZAKDPS-UHFFFAOYSA-L 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 229910001448 ferrous ion Inorganic materials 0.000 description 1
- 235000013305 food Nutrition 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910021506 iron(II) hydroxide Inorganic materials 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 230000003746 surface roughness Effects 0.000 description 1
- 238000004448 titration Methods 0.000 description 1
- 238000001291 vacuum drying Methods 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/05—Metallic powder characterised by the size or surface area of the particles
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/16—Making metallic powder or suspensions thereof using chemical processes
- B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
- B22F9/20—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from solid metal compounds
- B22F9/22—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from solid metal compounds using gaseous reductors
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B1/00—Preliminary treatment of ores or scrap
- C22B1/02—Roasting processes
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
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Abstract
本发明属于金属废料的预处理技术领域,具体涉及一种超细铁粉。所述铁粉的粒度D50≤20μm,铁含量≥97%,松装比重0.5‑1.5g/cm3。本发明的铁粉粒度小,纯度高,松装比重小。
Description
技术领域
本发明属于金属废料的预处理技术领域,具体涉及一种超细铁粉及其生产方法。
背景技术
铁粉是粉末冶金工业的基础原料之一,世界铁粉年产量约在85万吨左右。铁粉产量的85%用于粉末冶金零件的制造,其中70%-83%的粉末冶金零件用于汽车行业。其余铁粉用于化工、磁性材料、切割、焊条、发热材料等(“从铁粉生产状况看国内铁粉发展趋势”,葛立强,中国粉体工业,2006年第2期,第40页摘要1-3行,公开日2006年12月31日)。
对铁粉而言,铁粉越细,比表面积越大,活性越强,因而具有更强的电、磁、光以及催化、吸附和化学反应等特殊的性能,也因此在电磁、生物、医学、光学等诸多领域均具有广阔的应用前景(“低温还原制备超细铁粉的研究进展”,韩义林等,上海金属,2010年第32卷第1期,第47页第4-7行,公开日2010年01月31日)。因此,超细铁粉广泛应用于磁性材料、医药、食品、焊条制造、汽车尾气处理、化工、冶金、超硬材料、硬质合金、高密度合金、机械设备、涂料、橡胶制品颜料、种子优选、种子净化、土壤改良等领域(“超细铁粉的应用研究现状及进展”,吴绍华等,云南冶金等,2005年第34卷第5期,第34页左栏倒数第1段第1行、第34页右栏第2段第1-3行、第34页右栏第3段第2-3行及第35页左栏第2段第1-5行,公开日2010年10月31日)。
然而,现有的铁粉的粒径较粗(D50>45um),会降低其表面活性,增加烧结温度,影响产品的结构性能;会导致压坯的压制压力增大,增加模具的负担;同时还会增加其制品的表面粗糙度,降低零件的加工精度;此外,还会降低其在其它领域的磁性、催化性等特殊的性能,限制其应用领域。
发明内容
有鉴于此,本发明的目的在于提供一种粒径小的铁粉。
为实现上述目的,本发明的技术方案为:
铁粉,所述铁粉的粒度D50≤20μm,铁含量≥97%,松装比重0.5-1.5g/cm3。
所述D50是指累计粒度分布百分数达到50%时所对应的粒径,即大于该粒径的颗粒占50%,小于该粒径的颗粒也占50%。
所述松装比重是指铁粉自由充满标准容器后测得的单位体积的质量。
进一步,所述铁粉的粒度D90≤40μm。
所述粒度D90是指累计粒度分布百分数达到90%时所对应的粒径,即小于该粒径的颗粒占90%。
此外,发明人还发现,铁基复合粉生产原理是利用铁粉、硫酸铜溶液在一定的添加剂条件下进行的一个化学置换反应,Fe+Cu2+→Fe2++Cu,在这一个反应过程中,会产生大量的含高浓度亚铁离子的废液,废液与液碱反应生成含铁废渣,Fe2++2OH-=Fe(OH)2↓。目前是将产生的大量含铁废渣经压滤机压滤,滤渣请外厂家拉走处理,并且要支付一定的费用给厂家。这种处理方式浪费了铁资源,增加了废水处理成本。
本发明的目的之二在于保护所述铁粉的制备方法,具体为:
依次将生产铁基复合粉产生的含铁废渣进行洗涤、焙烧、破碎、还原、破碎风选,所述还原温度为800-1000℃,时间为130-170min,氢气通入量为1.5-3.0m3/h。
进一步,所述洗涤是指加工所述含铁废渣置于过滤-洗涤一体机中,加入水洗涤5h,再压滤至含水量≤20%。
进一步,所述焙烧的温度为700-800℃,时间为80-100min,通入空气量为2-4m3/h。
进一步,所述破碎是指破碎至粒径D97≤5μm。
进一步,所述铁粉的制备方法,具体为:依次将生产铁基复合粉产生的含铁废渣进行洗涤、焙烧、破碎、还原、破碎风选,所述洗涤是指加工所述含铁废渣置于过滤-洗涤一体机中,加入水洗涤5h,再压滤至含水量≤20%;所述焙烧的温度为700-800℃,时间为80-100min,通入空气量为2-4m3/h;所述破碎是指破碎至粒径D97≤5μm;所述还原温度为800-1000℃,时间为130-170min,氢气通入量为1.5-3.0m3/h。
本发明的有益效果在于:
本发明的铁粉粒径小,其粒径D50≤20μm,D97≤40μm。
本发明的铁粉纯度高,高达97%以上。
本发明的铁粉松装比重小。
本发明实现了铁资源的回收利用,降低了成本。
具体实施方式
所举实施例是为了更好地对本发明的内容进行说明,但并不是本发明的内容仅限于所举实施例。所以熟悉本领域的技术人员根据上述发明内容对实施方案进行非本质的改进和调整,仍属于本发明的保护范围。
以下含水量的检测方法为:取一定量的铁粉,放入真空干燥箱在105℃-110℃干燥2h,降低到室温,泄压,取出称重,计算前后重量差;
以下粒度采用激光粒度分析仪进行检测;
以下铁含量按照《GB/T 223.7-2002铁粉铁含量的测定重铬酸钾滴定法》进行检测;
以下松装比重按照《GB/T 1479.1-2011金属粉末松装密度的测定第1部分漏斗法》进行测定。
实施例1
超细铁粉的制备方法,具体为:
A.洗涤:将加工所述含铁废渣(含水量为40%)置于过滤-洗涤一体机中,加入水洗涤5h,再压滤至含水量≤20%,得到压滤块;
B.焙烧:将经洗涤处理得到的压滤块装进烧舟中,送入网带炉于800℃温度、通入空气量为3m3/h条件下焙烧90min,得到块状物;
C.破碎:将经焙烧处理得到的块状物置于分级式冲击磨中破碎至粒径D97(D97指累计粒度分布百分数达到97%时所对应的粒径,即小于该粒径的颗粒占97%;得到粉体;
D.还原:将步骤C得到的粉体装进烧舟中,送入网带炉于900℃温度、氢气通入量为1.5m3/h条件下还原处理150min;
E.破碎风选:将经还原处理得到的铁粉置于流化床打散分级机中进行破碎风选。
性能测试
对实施例1经破碎处理得到的铁进行粒度D50和D90、铁含量、松装比重等方面性能检测,结果如表1所示。
表1性能检测结果
由表1可知,实施例1得到的铁粉的粒度D50为19μm,D90为37μm,松装比重为1.238g/cm3。由此证明,本发明的铁粉粒度小,松装比重小,纯度高。
此外,应当理解,虽然本说明书按照实施方式加以描述,但并非每个实施方式仅包含一个独立的技术方案,说明书的这种叙述方式仅仅是为清楚起见,本领域技术人员应当将说明书作为一个整体,各实施例中的技术方案也可以经适当组合,形成本领域技术人员可以理解的其他实施方式。
Claims (2)
1.铁粉的制备方法,其特征在于,依次将生产铁基复合粉产生的含铁废渣进行洗涤、焙烧、破碎、还原、破碎风选,所述洗涤是指加工所述含铁废渣置于过滤-洗涤一体机中,加入水洗涤5h,再压滤至含水量≤20%;所述焙烧的温度为800℃,时间为90min,通入空气量为3m3/h;所述破碎是指破碎至粒径D97≤5μm;所述还原温度为900℃,时间为150min,氢气通入量为1.5m3/h;所述铁粉的粒度D50≤20μm,铁含量≥97%,松装比重0.5-1.5g/cm3。
2.根据权利要求1所述的制备方法,其特征在于,所述铁粉的粒度D90≤40μm。
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SU1342598A1 (ru) * | 1985-05-06 | 1987-10-07 | Украинский заочный политехнический институт им.И.З.Соколова | Способ получени железного порошка из пиритных огарков |
CN108080649A (zh) * | 2017-12-14 | 2018-05-29 | 新冶高科技集团有限公司 | 一种低温碳氢双联还原制备超细铁粉的方法 |
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