本文選題：硼精礦 + 活化焙燒�。� 參考：《天津科技大學(xué)》2017年碩士論文

【摘要】：硼化合物是重要的化工原料,廣泛用于冶金、建材、農(nóng)業(yè)、紡織、國防等領(lǐng)域。在我國硼資源中,用于生產(chǎn)硼化合物產(chǎn)品的原料主要為硼鎂礦和硼鐵礦,但長期的開采導(dǎo)致含硼量較高的硼鎂礦資源匱乏,品位較低的硼鐵礦資源逐漸成為生產(chǎn)硼產(chǎn)品的主要原料。合理地開采和利用低品位硼鐵礦資源,對解決我國硼資源短缺以及推動硼工業(yè)發(fā)展有著重大意義。針對我國硼化工現(xiàn)行生產(chǎn)過程存在的硼收率偏低,硼精礦活化焙燒機理不明確,浸出液碳解過程條件苛刻等問題,本文以硼鐵礦經(jīng)磁重選后的硼精礦為研究對象,系統(tǒng)開展了硼精礦活化焙燒與浸出液加壓碳化過程機理研究和工藝優(yōu)化。本文取得的主要創(chuàng)新性進(jìn)展如下:1、系統(tǒng)地考察了溫度、時間、焙燒氣氛等焙燒條件對硼精礦反應(yīng)活性的影響,發(fā)現(xiàn)硼精礦的反應(yīng)活性的提高可以通過調(diào)節(jié)焙燒溫度和時間,以及使用添加劑來實現(xiàn),焙燒氣氛對其影響較小。當(dāng)焙燒溫度在670～700℃,控制粒度d0.5為69.1μm左右,加入5g添加劑碳酸鈣5g,空氣氣氛下焙燒2.0h反應(yīng)活性可達(dá)到84.00%。2、利用TG-DSC、XRD、SEM、EDS等測試方法,對硼精礦焙燒過程中含硼組分和非含硼組分的物理化學(xué)變化進(jìn)行了研究,結(jié)果表明,硼精礦中含硼組分主要以硼鎂石和硼鎂鐵礦的形式存在,礦石的晶體結(jié)構(gòu)復(fù)雜,硼鎂石和硼鎂鐵礦共生關(guān)系密切。焙燒過程中,磁鐵礦被氧化,硼鎂石脫水分解生成易于浸出的遂安石,蛇紋石脫水分解生成鎂橄欖石,白云石分解為氧化物,這些物相的反應(yīng)促使礦石顆粒變得疏松,比表面積顯著增大,因此硼精礦的反應(yīng)活性提升。3、對焙燒后的硼精礦(熟硼礦)進(jìn)行碳解浸出,系統(tǒng)考察了溫度、時間、液固比等焙燒條件對硼精礦反應(yīng)活性的影響。結(jié)果表明,加入鈉鹽的類型對反應(yīng)的浸出率無影響,鈉鹽的加入量、反應(yīng)溫度和液固比對碳解反應(yīng)影響較小,CO2是碳解反應(yīng)的主導(dǎo)因素。碳解100g礦粉過程中,液固比為1.7: 1,反應(yīng)時間為1Oh,加入Na2CO3的質(zhì)量為12.8g,反應(yīng)溫度為135℃,通入濃度98%、壓力為0.8MPa的C02氣體,加入添加劑活性炭5g,浸出率達(dá)到峰值,為85.82%。4、研究了硼精礦碳解浸出過程機理。結(jié)果表明,碳解浸出過程中,熟硼礦中僅有遂安石反應(yīng),其余組分基本不參與發(fā)生反應(yīng)。在Na2CO3溶液中高溫高壓浸出,通入CO2氣體下,遂安石水解,硼進(jìn)入溶液相與Na+反應(yīng)生成硼砂,而鎂與C3O2-反應(yīng)生成MgCO3和4MgCO3·Mg(OH)2·4H20進(jìn)入殘渣相中達(dá)到分離硼鎂目的。在碳解過程中影響浸出率的關(guān)鍵因素為CO2的反應(yīng)速率。
[Abstract]:Boron compounds are important chemical materials, widely used in metallurgy, building materials, agriculture, textile, national defense and other fields. Among the boron resources in China, the raw materials used to produce boron compounds are mainly borite and boron iron ore, but the long term exploitation results in the shortage of boron mineral resources with high boron content. The low grade boron ore resource has gradually become the main raw material for the production of boron products. The rational exploitation and utilization of low grade boron iron ore resources is of great significance to solve the shortage of boron resources and promote the development of boron industry in China. In view of the problems existing in the present production process of boron chemical industry in China, such as low boron yield, unclear activation roasting mechanism of boron concentrate and harsh conditions of carbon hydrolysis process of leachate, boron concentrate after magnetic gravity separation is taken as the research object in this paper. The mechanism and process optimization of activation roasting of boron concentrate and pressure carbonization of leaching solution were carried out systematically. The main innovative progress in this paper is as follows: 1. The effects of calcination conditions such as temperature, time and roasting atmosphere on the reaction activity of boron concentrate are systematically investigated. It is found that the increase of reaction activity of boron concentrate can be achieved by adjusting the calcination temperature and time. The effect of roasting atmosphere on it is small. When the calcination temperature is 670,700 鈩，

本文編號：1853401