【摘要】：煤矸石的主要礦物成分為高嶺石等粘土類礦物,具有潛在的火山灰活性,若將其活化激發(fā)后作為膠凝材料一方面可以解決煤矸石無序堆放引起的占用土地資源、污染環(huán)境等問題,另一方面可以作為礦山膠結(jié)充填材料中的膠凝材料,降低充填開采成本。目前有關(guān)煤矸石火山灰活性研究主要集中在氧化鈣含量在3%左右的低氧化鈣煤矸石,活化過程中未能實(shí)現(xiàn)煤矸石中的硅鋁分離,導(dǎo)致煤矸石火山灰活性未能充分激發(fā)。本文以新陽煤礦高氧化鈣煤矸石為研究對象,通過室內(nèi)試驗(yàn)、理論推導(dǎo)等方法并結(jié)合XRD、XRF、離子濃度檢測(ICP-AES)等現(xiàn)代測試技術(shù)手段對新陽煤礦高氧化鈣煤矸石火山灰活性激發(fā)進(jìn)行了研究。首先,通過對新陽煤礦煤矸石礦物成分、化學(xué)成分分析發(fā)現(xiàn),煤矸石主要礦物成分為高嶺石等粘土礦物,主要化學(xué)成分為SiO_2、Al_2O_3且含有較高含量的CaO屬于粘土類高氧化鈣含量煤矸石具有潛在火山灰活性。其次,通過研究機(jī)械活化高氧化鈣煤矸石-水泥漿體中煤矸石、水泥水化程度隨煤矸石摻量、水膠比、齡期的變化規(guī)律發(fā)現(xiàn):⑴漿體中機(jī)械活化煤矸石摻量一定時(shí),隨水膠比、齡期的增大,煤矸石和水泥水化程度均增大,且煤矸石摻量為30%時(shí),漿體中煤矸石早期水化速率較好,煤矸石摻量為40%時(shí),漿體中水泥早期水化速率較好;一定齡期時(shí),隨煤矸石摻量的增大、水膠比的減小漿體中煤矸石水化程度呈減小的變化規(guī)律,隨煤矸石摻量的增大、水膠比的增大漿體中水泥水化程度呈增大的變化規(guī)律;⑵結(jié)合試驗(yàn)結(jié)果通過對純水泥水化公式修正,提出了機(jī)械活化高氧化鈣煤矸石-水泥漿體中水泥和煤矸石水化程度預(yù)測模型。再次,在機(jī)械活化煤矸石試驗(yàn)的基礎(chǔ)上通過對機(jī)械-熱激發(fā)高氧化鈣煤矸石熱分解規(guī)律、電化學(xué)規(guī)律以及活化高氧化鈣煤矸石-水泥漿體相關(guān)性能的研究發(fā)現(xiàn):⑴隨活化溫度的升高,煤矸石物相變化經(jīng)歷了四個階段:即煤矸石吸附水和結(jié)構(gòu)水揮發(fā)階段、失重穩(wěn)定階段、有機(jī)碳質(zhì)等揮發(fā)階段和煤矸石礦物分解階段,700℃時(shí),煤矸石分解速率達(dá)到最大值;⑵高氧化鈣煤矸石溶于蒸餾水時(shí),煤矸石中的CaO先與水反應(yīng)生成Ca(OH)2,形成一個強(qiáng)堿強(qiáng)極性的溶解環(huán)境,加速活化煤矸石中活性離子的溶出速率,接著活性Si~(4+)、Al~(3+)與Ca~(2+)、OH~-反應(yīng),生成難溶物質(zhì);⑶隨活化溫度的升高,活化高氧化鈣煤矸石-水泥凈漿粘度值、單軸抗壓強(qiáng)度值先增大后減小,700℃時(shí)達(dá)到最大值,而凈漿凝結(jié)時(shí)間呈相反的變化規(guī)律,700℃達(dá)到最小值,得出機(jī)械-熱活化煤矸石的最佳活化溫度為700℃。最后,在機(jī)械-熱復(fù)合活化的試驗(yàn)基礎(chǔ)上,通過對機(jī)械-熱-化學(xué)激發(fā)高氧化鈣煤矸石電化學(xué)規(guī)律和活化高氧化鈣煤矸石-水泥漿體相關(guān)性能的研究發(fā)現(xiàn):⑴隨活化溫度升高,各機(jī)械-熱-化學(xué)復(fù)合活化高氧化鈣煤矸石抗壓強(qiáng)度呈上升的變化趨勢,隨Na_2CO_3與高氧化鈣煤矸石質(zhì)量比的增大,各齡期高氧化鈣煤矸石-水泥凈漿抗壓強(qiáng)度呈降低趨勢;隨活化溫度升高,碳酸鈉比例增加,高氧化鈣煤矸石-水泥凈漿粘度呈增大的變化規(guī)律,而漿體初凝、終凝時(shí)間呈降低的變化規(guī)律;⑵碳酸鈉比例和活化溫度共同決定了活化后煤矸石在蒸餾水中的電導(dǎo)率值,而活化后高氧化鈣煤矸石粉溶液PH主要是受活化溫度的控制。
[Abstract]:The main mineral component of the coal stone is a clay mineral such as kaolinite, and has the potential pozzolanic activity. and on the other hand, can be used as a cementing material in a mine cement filling material to reduce the filling and mining cost. At present, the research on the pozzolanic activity of the coal-fired stone is mainly focused on the low-calcium oxide, which has a calcium oxide content of about 3%, and fails to separate the silicon and aluminum in the coal-fired stone during the activation process, leading to the failure of the pozzolanic activity of the coal-fired stone to be fully excited. In this paper, the active excitation of high-calcium oxide in Xinyang coal mine is studied by means of laboratory test, theoretical derivation and other modern test methods such as XRD, XRF, and ion concentration detection (ICP-AES). First, through the analysis of the mineral composition and chemical composition of the coal-fired stone in Xinyang coal mine, the main mineral component of the coal-stone is kaolinite and other clay minerals. The main chemical components are SiO _ 2 and Al _ 2O _ 3, and the higher content of CaO, which belongs to the high-calcium oxide content of the clay, has the potential pozzolanic activity. Secondly, through the study of the change of the degree of hydration of the coal and the cement in the high-calcium oxide-coal-stone-cement paste, the change of the degree of hydration of the cement with the amount of the coal-fired stone, the ratio of the water-to-cement and the age of the cement, it is found that, with the increase of the water-cement ratio and the age, The hydration degree of the coal-fired stone and the cement is increased, and when the amount of the coal-fired stone is 30%, the early hydration rate of the coal-fired stone in the slurry body is good, the early hydration rate of the cement in the slurry body is better when the amount of the coal-fired stone is 40%, and the amount of the coal-fired stone is increased with the increase of the amount of the coal-fired stone at a certain age, The change law of the degree of hydration of the coal and stone in the slurry body of the ratio of the water-to-cement ratio increases with the increase of the amount of the coal and the cement, and the degree of hydration of the cement in the slurry body increases with the increase of the amount of the coal-cement, and the combined test result is corrected by the formula of the hydration of the pure cement. In this paper, the hydration degree prediction model of cement and coal-stone in high-calcium oxide-stone-cement paste is presented. Thirdly, on the basis of the mechanical activation of the coal-stone test, the thermal decomposition of the high-calcium oxide, the electrochemical law and the activation of the high-calcium oxide-coal-stone-cement slurry were studied. The phase change of the coal-fired stone material is subjected to four stages, namely, the adsorption water of the coal-fired stone and the volatilization phase of the structure water, the loss-of-weight stability stage, the volatilization phase of the organic carbon and the mineral decomposition stage of the coal-fired stone, the decomposition rate of the coal-fired stone reaches the maximum value at the time of 700 DEG C, The CaO first reacts with water to form Ca (OH) 2, to form a strong strong strong-polar dissolution environment, to accelerate the dissolution rate of active ions in the activated coal-fired stone, and then the active Si ~ (4 +), Al ~ (3 +) and Ca ~ (2 +), OH ~-to react, to generate insoluble substances; the temperature increases with the activation temperature. The value of the viscosity of the activated high-calcium-oxide-coal-stone-cement is increased, the value of the single-axis compressive strength is decreased, the maximum value is reached at 700 鈩，

本文編號：2344489