煤中溴的淋滤行为研究  

Leaching characteristics of bromine in coal

作　　者：彭炳先[1,2] 吴代赦[1] 

机构地区：[1]南昌大学环境与化学工程学院,江西南昌330031 [2]江西师范大学化学化工学院,江西南昌330022

出　　处：《燃料化学学报》2011年第9期647-651,共5页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金(40133010)

摘　　要：在不同pH值条件下对来自重庆磨心坡矿煤样进行柱淋滤实验,用电感耦合等离子体质谱法(ICP-MS)测定煤中溴的含量及四种淋滤介质在不同时间段获取的淋出液中溴的浓度。结果表明,淋滤液的pH值、淋滤时间、煤中溴的赋存形态及在煤中赋存部位对溴的淋出有重要影响。淋滤液的酸性越强,煤中溴的最大淋出浓度越大,一定时间内溴的总淋出率也越高。pH值为2的淋滤液,在淋滤前40 h内淋出溴的量占总淋出量的80.65%;pH值为4的淋滤液,在淋滤前50 h内淋出溴的量占总淋出量的89.42%。在酸性淋滤液作用下,首先被淋出的是存在煤颗粒表面的碳酸盐态和铁锰结合态溴,然后煤基质内部的水溶态和离子交换态溴才被淋出。柱淋滤实验表明,煤中溴在风化过程中,会被酸性雨水淋溶出来进入周围土壤或地表水体,造成周围环境溴的富集。Comparative column leaching experiments were carried out on a coal sample collected from MoxinpoMine in Chongqing,Southwest China.Different acid solutions were used to investigate the leaching behavior and potential environmental effects of bromine in coal.The leaching rate and maximum leached concentration of bromine were calculated based on the concentration of bromine in different resulting leachates measured by inductively coupled plasma mass spectrometry.The results show that the modes of occurrence and locations of bromine in coal,time,and pH value played an important role in controlling the leaching behavior of bromine in coal.At 120 h,the maximum leached concentration and total leaching rate of bromine in coal increased with an increase in the acidity of the leaching solution.The amount of bromine released from coal leached at pH of 2 comprised about 80.65% of its total leached amount for 40 h,whereas it was 89.42% at pH of 4 for 50 h.When leached by an acidic solution,the bromine occurring in carbonate and Fe-Mn oxides located on the surface of coal particles may be released first,followed by the bromine in water-soluble and exchangeable forms in the interior of the coal matrix.The experiment shows that the bromine in coal may be leached out by acidic rain and enters the surrounding soil and surface water,resulting in the enrichment of bromine in the environment.

关 键 词：煤 溴 淋滤实验 赋存形态 

分 类 号：X142[环境科学与工程—环境科学]