石煤中钒元素在燃烧前后赋存状态变化的研究

石煤是一种可综合利用的矿产资源,提取石煤中钒、钼、镍等金属是其综合利用之一.石煤在发电燃烧过程中钒的物相发生显著变化,而钒物相的变化对钒的可浸出性产生较大的影响.笔者采用选择性连续提取方法对四川某地石煤原矿和石煤飞灰进行分析研究,发现石煤原矿中钒主要存在于硅铝酸盐相和有机质相中,部分存在于铁锰氧化物相及吸附态中,极少部分存在于碳酸盐相中.而石煤发电飞灰中钒主要存在于有机质相、硅铝酸盐相和铁锰氧化物相中,少量的钒以吸附态形式赋存.燃烧过程中石煤的各种含钒矿物发生离解,其中的钒得到释放并被氧化成高价态.高价钒一部分与Na、Cl等结合生成可溶性化合物,形成吸附态的钒;另一部分与Fe、Na、Ca等发生反应生成难溶性化合物,并以一定形式富集在飞灰的有机质相、硅铝酸盐相和铁锰氧化物相中.

A STUDY ON THE VARIATION OF V ELEMENT EXISTENCE IN STONE COAL BEFORE-AFTER COMBUSTION

The stone coal is a mineral resources which can be available metal extraction from stone coal is one of the many usages of stone coal. The comprehensively. V, Mo, Ni, etc V facies varies evidently in the stone coal combustion of generate electricity. And the V facies variation has a great influence on the leaching of V. We have had a study on the raw stone coal and coal dust with select continuous exaction method, discovered the V in raw stone coal mainly exists in Si aluminate and organic facies, a part of it in Fe-Mn oxide facies and adsorption state, only a few in carbonate facies. In the coal dust, V mainly exists in organic facies, Si aluminate facies and Fe-Mn oxide facies, a few V in adsorption state. In the combustion, various V-bearing minerals in stone coal dis- sociate. The V is released and oxidized, to be in high valence state. A part of high valence V in combination with Na, C1, etc, forms the soluble compound, the V in adsorption state; another ones react on Fe, Na, Ca, form difficultly soluble compound and concentrate in the organic facies, Si aluminate facies and Fe-Mn oxide facies in a certain form.