本文關(guān)鍵詞： 真空 碳熱還原 碳化鈦 含鈦高爐渣 酸浸　出處：《重慶大學(xué)》2015年碩士論文　論文類(lèi)型：學(xué)位論文

【摘要】：Ti C熔點(diǎn)高、硬度好、化學(xué)穩(wěn)定性好,廣泛應(yīng)用于切削模具、金屬陶瓷,耐熱合金和硬質(zhì)合金,我國(guó)釩鈦磁鐵礦高爐冶煉工藝使得原礦中超過(guò)50%的鈦資源進(jìn)入爐渣中(Ti O2含量22%-25%),常稱之為含鈦型高爐渣,是我國(guó)特有的含鈦高爐渣,是一種具有利用價(jià)值的二次鈦資源,但自上世紀(jì)70年代實(shí)現(xiàn)釩鈦磁鐵礦高爐渣冶煉以來(lái),這種有價(jià)二次資源一直未實(shí)現(xiàn)工業(yè)化利用,堆積量超過(guò)7000萬(wàn)噸,且現(xiàn)在每年仍有350萬(wàn)噸到400萬(wàn)噸的產(chǎn)量,造成鈦資源極大浪費(fèi)的同時(shí),帶來(lái)了嚴(yán)重的環(huán)保壓力,本研究提出真空碳熱還原聯(lián)合酸浸新工藝,進(jìn)行含鈦高爐渣制備Ti C的基礎(chǔ)研究,擬通過(guò)本論文的研究,獲得硅鈦分離,降低二次污染,獲得Ti C的理論基礎(chǔ)和優(yōu)化實(shí)驗(yàn)條件。為我國(guó)含鈦高爐渣高效綜合利用提供實(shí)驗(yàn)研究基礎(chǔ)。主要結(jié)論如下:①爐渣成分為五種主要氧化物組成時(shí)(Ca O-Si O2-Mg O-Al2O3-Ti O2):Ti O2被C還原生成Ti C的過(guò)程中,有著眾多的中間產(chǎn)物的生成,在常壓下1000℃以下,Ti3O5,Ti2O3,Ti O中間產(chǎn)物先于Ti C生成。隨著溫度升高和壓力減小,Ti C更容易得到。常壓和真空下,Ca O和Al2O3難還原,反應(yīng)溫度高;常壓下,Si O2和Mg O還原難度大,但隨著真空度的增加,可實(shí)現(xiàn)Si O2到Si O,Mg O到Mg的還原。②爐渣成分為四種主要化合物時(shí)(Ca Ti O3,Ca Fe(Si O3)2,Ca Mg(Si O3)2和Mg Al2O4):還原難易程度Ca Ti O3Ca Fe(Si O3)2Ca Mg(Si O3)2Mg Al2O4。103Pa壓力下,反應(yīng)起始溫度為1200℃,還原Ca Ti O3可得到Ti C,當(dāng)壓力達(dá)到100Pa時(shí),反應(yīng)起始溫度低于900℃。Ca Fe(Si O3)2被C還原,生成Ca O,Fe和Si O,103Pa壓力下,還原溫度低于1300℃。Ca Mg(Si O3)2碳熱還原也會(huì)隨著壓力的降低逐漸被還原而得到Ca O,Mg,Si O。Mg Al2O4被C還原生成Mg和Al相對(duì)較難。③含鈦高爐渣還原產(chǎn)物優(yōu)勢(shì)區(qū)圖結(jié)果表明:可通過(guò)調(diào)節(jié)體系氧分壓和溫度得到純度Ti C區(qū)域,且Ti C會(huì)隨著溫度的升高和壓力的降低,穩(wěn)定存在區(qū)間持續(xù)變大。Si C和Ti C共同的穩(wěn)定存在區(qū)間會(huì)隨著溫度的升高而變大,隨著壓力的降低而減小。④常壓、保護(hù)性氣氛條件下,含鈦高爐渣還原難度大。現(xiàn)場(chǎng)渣經(jīng)高能球磨后再真空碳熱還原,可得到Ti C產(chǎn)物,但能耗較高。⑤一定粒度的含鈦高爐渣在合適的真空度、還原溫度及渣碳質(zhì)量比條件下,真空碳熱還原還原后,經(jīng)進(jìn)一步酸浸處理后,可得到純Ti C.
[Abstract]:Tic has high melting point, good hardness and good chemical stability. It is widely used in cutting dies, cermets, heat-resistant alloys and cemented carbides. The blast furnace smelting process of vanadium titanomagnetite in China makes more than 50% titanium resources in the raw ore enter into the slag with 22- 25o 2 content, which is often called titanium-bearing blast furnace slag. It is a unique titanium-bearing blast furnace slag in China and is a kind of secondary titanium resource with utilization value. However, since the smelting of vanadium-titanomagnetite blast furnace slag in -30s, this valuable secondary resource has not been industrially utilized, with an accumulation of more than 70 million tons, and now there are still 3.5 million to 4 million tons of output per year. This paper presents a new technology of vacuum carbothermal reduction combined with acid leaching to prepare tic from titanium-bearing blast furnace slag. Through the research in this paper, the separation of silicon and titanium is obtained. Reduce secondary pollution, The theoretical basis and optimized experimental conditions of tic were obtained, which provided the experimental research basis for the efficient comprehensive utilization of the blast furnace slag containing titanium in China. The main conclusions are as follows: (1) when the slag is composed of five main oxides, Ca O-SiO _ 2-Mg O-Al _ 2O _ 3-TiO _ 2o _ 2 / TIO _ 2 / TIO _ 2 coating is obtained. In the process of reducing to Ti C, There are many intermediate products. The intermediate products of Ti _ 3O _ 5 and Ti _ 2O _ 3O _ 3O _ 3O _ 3O _ 3O _ 2O _ 3O _ 2O _ 3O _ 2O _ 3Ti _ 2O _ 3Ti _ 2O _ 3 are formed before tic under 1000 鈩，

本文編號(hào)：1499932