湖北杨家堡石煤中钒的价态研究

V-bearing stone coal is a new kind of vanadium resource.The oxidation states of vanadium in the Yangjiapu stone coal were analyzed by means of electro-analysis and mineral separation.Sample analysis gave:93.8% V(Ⅲ）and 6.2%V(Ⅳ）Neither V(Ⅱ）nor V（Ⅴ）was present in the stone coal.Valency analysis showed that vanadium was present in the form of VO^2+n vanadium porphyrin.The distribution of oxidation states of vanadium shows that in the presence of organic matter and pyrite only a small amount of V（Ⅲ）can be oxidized into V(Ⅳ）when the stone coal is roated.At 450℃ pyrite was oxidized into α Fe2O3 and 95% of the arganic matter were oxidized,Under such conditions 85% of V(Ⅲ） were oxidized into V(Ⅳ） At about 520℃ V(Ⅲ） was completely oxidized into V（Ⅳ） At 800°-1000℃ 91% of vanadium in the stone coal were oxidized into V(Ⅴ）.Over the range of high temperatures no more vanadium was oxized into V(Ⅴ）that is to say,an equilibrium was established.Salt roasting may play a very important role in extracting vanadium from the stone coal.From the results of our experiments it is considered that sodium chloride cannot only promote the oxidation of vanadium,but also react with vanadium to form soluble vanadate.It is evident that 800℃ is the optimum temperature at which vanadium is extracted from stone coal.

关于环境影响评价资格审查制度的探讨

对从事环境影响评价的单位实行资格审查,是环境管理制度化的有力形式。本文通过对环境评价现状和评价队伍构成的分析,提出了当前的资格审查工作应从实际出发,不宜过于模式化、规范化;应提倡与推动评价队伍的多方位发展,并给予“专项——等级”的划分。这样做的好处不仅是能够及时纠正超越能力的承担现象,还能突出与发挥各单位的不同实力,从而通过专项审查,综合结论,保证环境影响评价报告书的质量。