不同变质类型煤中环境敏感性微量元素的精细化学结构与地质意义

This project will collect coal and rock samples forming in different geological processes in Huainan and Huaibei Coalfield, where were experienced multiphase reformation effects of tectonic movement and magmatic intrusion. The high-precision instrumental analysis (X-ray absorption fine structure spectroscopy, Electron Probe X-ray Microanalysis, etc.) in the framework of coal petrology, sedimentology, mineralogy, geology and geochemistry will be conducted to investigate the distribution characteristics and fine chemical structures of environmentally sensitive trace elements. The objectives of this project are to reveal the relationships between metamorphosed effects and the enrichments and transformations of environmentally sensitive trace elements, analysis the relationships between metamorphosed effects and transformations of associations of environmentally sensitive trace elements, determine the transformation behaviors of environmentally sensitive trace elements in response to metamorphosed effects and finally construct the geochemical patterns of environmentally sensitive trace elements under various metamorphosed effects. The results of this study are expected to provide important information for developing coal clean technology and controlling the emissions of environmentally sensitive trace elements.

本项目以经历多期地质构造运动和岩浆侵入改造作用的安徽两淮煤田为例，以不同变质类型的煤为研究对象，通过采集不同成煤作用、不同岩浆作用和不同构造作用影响下的煤岩样品，结合煤岩学、沉积学、矿物学、地质学和地球化学等交叉理论，运用X射线吸收精细结构谱和电子探针X射线微区分析等高精度分析测试手段，研究不同煤变质作用下煤中环境敏感性微量元素的分布规律和精细化学结构，揭示煤变质作用与环境敏感性微量元素迁移、聚集的关系，探讨煤变质作用与环境敏感性微量元素精细结构转化的耦合关系，阐明环境敏感性微量元素在不同煤变质作用下的迁移富集机理，建立环境敏感性微量元素精细化学结构与煤变质作用的地球化学模式，为发展洁净煤技术、控制污染物排放提供理论依据。

成煤变质作用是煤中微量元素的分布、富集、赋存与迁移转化的重要因素。本项目以不同变质类型的煤为研究对象，通过采集不同成煤作用、不同岩浆作用和不同构造作用影响下的煤岩样品，运用X射线吸收精细结构谱和电子探针X射线微区分析等高精度分析测试手段，研究了不同煤变质作用下煤中环境敏感性微量元素的分布规律和精细化学结构，研究发现在成煤变质作用下，煤岩组成与微量元素含量均发生了迁移转化，微量元素在天然焦中存在异常富集，碳酸盐结合态的比重增加；微量元素在不同构造煤中可以分为富集型、损缺型和稳定性，其中As、Cd和Pb等亲铜元素是富集型元素，阐明了环境敏感性微量元素在不同煤变质作用下的迁移富集机理，本项目研究成果可为煤炭绿色开采与清洁利用提供了理论依据。