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1、湘潭大学 硕士学位论文 微波对石煤提钒的影响 姓名：欧阳国强 申请学位级别：硕士 专业：环境工程 指导教师：田学达 20080508 微波对石煤提钒的影响 I 摘摘 要要 石煤是一种独立含钒矿物，是提取 V2O5 的重要矿物资源。传统的石煤提钒工艺 采用钠盐焙烧，不仅污染大，而且 V2O5的回收率低。硫酸直接浸出法，则 H2SO4 耗 量大，除杂困难，难于得到合格的钒产品。 微波是一种频率在 300300000MHz 的电磁波。将微波应用于冶金工艺，显示出 加热均匀、加热速度快、高效节能并提高冶金效能等许多优点。本文首次将微波技术 引入石煤提钒工艺中，考察了添加剂微波焙烧工艺和微波湿法酸浸工艺
2、条件下，微 波对石煤中钒浸出的影响，并分别与传统焙烧工艺和传统加热湿法酸浸工艺进行了比 较。 研究表明，微波处理石煤能显著提高钒的浸出性能。经微波处理后，矿物组分 间热膨胀系数不同而致使矿样颗粒的龟裂，增大了矿样的比表面积，促使 V2O5与添 加剂（Na2CO3）反应，形成可溶性 NaVO3。 通过微波焙烧与传统焙烧后的对比实验，考察焙烧温度、焙烧时间和添加剂用量 对石煤提钒的影响，结果表明，微波焙烧温度为700 C，焙烧60 min，添加剂(Na2CO3) 用量为矿样质量的6 %时，V2O5浸出率达到76.7 %以上；800 C下，经微波焙烧60 min， 矿样中小于0.074 mm粒级的含
3、量从65.0 %提高到76.1 %。 根据微波焙烧前后矿样粒度的 变化，提出了微波焙烧过程矿样裂解模型为： -脉石 -钒矿物 用此模型可以解释微波焙烧能够提高石煤中V2O5浸出率的原因。 利用微波对石煤进行强化浸出，在微波功率为200 W、硫酸用量为矿样的16 %、微 波辐射时间为60 min和液固比为2的条件下，石煤V2O5浸出率达到66.5 %。 在微波强化浸出过程中对反应体系进行温度测定，试验结果表明，在到达沸点之 前，反应体系为非恒温反应过程，反应体系升温公式为： 0 0 t p P TTdt C W =+ 分析了微波辐射条件下，石煤提钒的动力学特征，根据动力学推导和实验数据结 微波对
4、石煤提钒的影响 II 果拟合出，钒在反应体系中的浸出速率数学模型为： 1 3 2 1 (1)6186.8470 ln4.1865 x TT = 浸出液经铵盐沉钒， V2O5总回收率为 93.0 %以上。 钒酸铵沉淀烘干, 在 400500 下煅烧，得五氧化二钒粉末，对产品进行检测，其纯度达到国家标准。 通过把微波技术引用到石煤提钒中，不但减少了环境污染，而且有效提高了资源 利用率。 关键词：微波； 石煤； 钒； 焙烧； 强化浸取 微波对石煤提钒的影响 III Abstract The stone coal that is one kind of independence contains th
5、e vanadium mineral, is the important mineral resources of leaching of vanadium. The traditional stone coal leaching of vanadium craft to use the sodium salt roasting have some demerits, like big pollutation and low leaching rate. When sulfuric acid direct leaching,will consume a lot H2SO4 and is dif
6、ficult to eliminates mixed, and difficulty with obtains the qualified vanadium product. The microwave is one kind of frequency in the 300300000 MHz electromagnetic wave.It have many merits like heats up even, the high rate of heating and so on when applies the microwave to the metallurgical technolo
7、gy. This is first time we raise the microwave technology introduction stone coal in the leaching vanadium craft.The influence of microwave to the stone coal in the vanadium leaching were studied under the chemical additive-microwave roasting craft and microwave strengthening leaching process craft c
8、ondition, and separately comparison texts of the traditional roasting craft and the tradition leaching craft. Test results showed that the pretreatment of stone coal by microwave can notable improve the rate of V2O5 leaching. The grain of sample have chapped and the specific surface area have became
9、 bigger by microwave roasting. The microwave roasting made the V2O5 reacting with additive (Na2CO3), and createing soluble NaVO3. Comparison texts of microwave roasting and conventional roasting for stone coal were carried out to investigate the effects of roasting temperature, roasting time and roa
10、sting additive dosage on vanadium extraction. Test results showed that V2O5 leaching rate was more than 64.1 % when the test sample was microwave roasted at 700 C for 60min, with additive Na2CO3 dosage of 6 %.Size analysis indicated that the percent fraction of -0.074 mm particles increased from 65.
11、0 % to 76.1 % after the sample was microwave roasted at 800 C for 60min.A disruption model of sample in microwave roasting process, by which the reason for the improvement of V2O5 leaching rate can be explained, was suggested.The model is: - gangue - vanadium mine The application of microwave in V2O
12、5 leaching , can have an effect to shorten the leaching time , reducing the energy consumption, and being able to improve the V2O5 微波对石煤提钒的影响 IV leaching rate. The microwave power，leaching time，pH and solid liquid ratio were studied. Test results showed that the leaching rate is 64.1 % of direct aci
13、d leaching when microwave eradiating. Carries on the temperature measurement in the microwave strengthening leaching process to the reacting system, the test result indicated, in arrives in front of the boiling point, the reacting system for the non- constant temperature reaction process, the reacti
14、ng system elevation of temperature formula is: 0 0 t p P TTdt C W =+ The leaching rate mathematic model was built under the microwave irradiation condition: 1 3 2 1 (1)6186.8470 ln4.1865 x TT = The total reclaim of V2O5 is above 93.0 % when added ammonium salt in leaching liquid. Made the product ro
15、asting in boiling stove inside under 400 500 after dried and detecting the V2O5 powder. The results showed that the product reaches the national standard. We used microwave technology in stone caol of leaching V2O5 , not only reduced the environmental pollution, moreover effectively raised the resou
16、rces use factor. Key words: microwave; stone coal; vanadium; roasting; strengthen leaching 湘潭大学湘潭大学 学位论文原创性声明学位论文原创性声明 本人郑重声明：所呈交的论文是本人在导师的指导下独立进行研究所 取得的研究成果。除了文中特别加以标注引用的内容外，本论文不包含任 何其他个人或集体已经发表或撰写的成果作品。对本文的研究做出重要贡 献的个人和集体，均已在文中以明确方式标明。本人完全意识到本声明的 法律后果由本人承担。 作者签名： 日期： 年 月 日 学位论文版权使用授权书学位论文版权使用授权书 本学位论文作者完全了解学校有关保留、使用学位论文的规定，同意 学校保留并向国家有关部门或机构送交论文的复印件和电子版，允许论文 被查阅和借阅。本人授权湘潭大学可以将本学位论文的全部或部分内容编 入有关数据库进行检索，可以采用影印、缩印或扫描等复制手段保存和汇
