摘要
本文讨论了由风化作用与首次发现的烧石灰两种因素构成的硒污染。对硒矿石的可溶性及不等时可溶性硒浸取试验表明,不断运动的,成分复杂的,具有一定酸碱度的天然水溶液对硒矿石长期作用后,能分解出大量的元素硒,这些元素硒是参与形成亚硒酸盐和硒酸盐的源泉。由此说明,风化作用是硒污染的因素之一。用硒矿石(石煤)作燃料烧石灰时,除产生有毒废气外,关键是残留在硒矿石烧渣中的硒,经测定竟是地表硒含量的数倍至数十倍,故硒矿石烧渣经风化扩散后能严重污染环境。
Selenium pollution in Yutangba selenium mining area in southwestern Hubei caused serious selenium intoxication of local inhabitants through the food chain. It is estimated that the selenium content taken in by each person daily in the mining area is more than 30 mg. The Yutangba selenium deposit occurs in siliceous rocks of the Permian Maokou Formation. The selenium content at shallow depths is commonly (100 - 5400) × 10-6and may reach a maximum of 8390 ×10-6, being generally (5 - 300) × 10-6 higher than that at the surface.This paper discusses selenium pollution cuased by weathering and burning of lime. Experiments of soluble selenium leaching of selenium ore indicated that the content of selenium leached from alkaline solutions is the highest, being 73. 60×10-6, next comes that from acid solutions, being 0. 38×10-6, and that from distilled water is the lowest, being 0. 02×10-6, Experiments of soluble selenium leaching with different time durations indicated that more selenium can be leached in a longer leaching time or in the moving leaching solution. The elemental selenium is a continuous source for the formation of selenate and selenite, It follows thus that weathering is one of factor responsible for selenium pollution. When selenium ore (stone coal )is used as fuel for burning lime, the main pollutant is selenium left in the cinder of selenium ore besides selenium oxide and hydrogen selenium. Its content was determined to be up to (600-840) × 10-6, being a few to a few dozens of times higher than the ordinary selenium content (7 - 164) ×10-6, at the surface. So after weathered and diffused, the cinder of selenium ore left after burning of lime can pollute environment seriously.The measures such as planting selenium-rich plants and burial or total utilization of the waste of selenium ore etc. can actively prevent selenium pollution at Yutangba.
出处
《地质论评》
CAS
CSCD
北大核心
1995年第2期121-126,共6页
Geological Review
关键词
硒
污染
渔塘坝
地质环境
selenium pollution, experiment of soluble selenium leaching, Yutangba
