Composition and quality of coals in the Huaibei Coalfield, Anhui, China

The Huaibei Coalfield, Anhui Province, China, is one of the largest coalfields in China. The coals of Permian age are used mainly for power generation. Coal compositions and 47 trace elements of the No. 10 Coal of the Shanxi Formation, the No. 7, 5, and 4 Coals of the Lower Shihezi Formation, and the No. 3 Coal of the Upper Shihezi Formation from the Huaibei Coalfield were studied. The results indicate that the Huaibei coals have low ash, moisture, and sulfur contents, but high volatile matter and calorific value. The ash yield increases stratigraphically upwards, but the volatile matter and total sulfur contents show a slight decrease from the lower to upper seams. Magmatic intrusion into the No. 5 Coal resulted in high ash, volatile matter, and calorific value, but low moisture value in the coal. Among the studied 47 trace elements, Ba, Co, Cr, Cu, Hg, Mo, Ni, Pb, Sb, Th, U, V, and Zn are of environmental concerns. Four elements Hg, Mo, Zn, and Sb are clearly enriched in the coals as compared with the upper continental crust.     

安徽淮北平原浅层地下水水质特征分析

以安徽淮北平原浅层地下水中的水质状况为研究对象,有针对性地采集了浅层地下水水样151个,应用多种方法测试了26种水样指标。综合分析结果表明:安徽淮北平原浅层地下水色度、浊度超标率小于10%;pH均值为7.6,为中性偏碱性水;HCO3—Na.Ca、HCO3—Na、SO4—Na、HCO3.SO4—Na.Mg等4种水化学类型占62.9%;硬度和TDS均值分别为481mg/L,641mg/L;Fe、Mn超标率分别为50.8%,46.9%;F-均值为1.4mg/L,低洼地势含氟矿物的溶解是导致F-局部偏高的主要原因,最高可达4.1mg/L;CODMn变化范围为1.0～3.5mg/L,有机污染程度低;三氮浓度随深度的增加而减少,农药化肥的过量使用是导致NO3--N和NH4+-N超标的主要原因,NO2--N超标19.1%,且与Fe2+浓度呈正相关关系(相关系数为0.933)。主成分分析发现,地下水的交换吸附作用、溶滤作用,原始沉积环境以及农业生产活动是影响其水质的主要因素。     

Further Information of the Associated Li Deposits in the No.6 Coal Seam at Jungar Coalfield,Inner Mongolia,Northern China

Total 138 coal samples and 14 parting samples were taken from the No. 6 Seam of the Jungar Coalfield, Inner Mongolia. These samples were analysed by optical microscopy, sequential chemical extraction procedure (SCEP), inductively coupled plasma mass spectrometry (ICP-MS), X-ray powder diffraction (XRD), and scanning electron microscope in conjunction with an energy-dispersive X-ray spectrometer (SEM-EDX) analysis. The results indicate that the Li contents have reached the industrial grade of the coal associated Li deposit, and the total Li reserves have reached 2406600 tons, that is, 5157000 tons Li2O in the No. 6 seam in the Jungar Coalfield. The sequential chemical extraction procedure results suggest that the Li concentration is mainly related to inorganic matter. The minerals in the coals consist of kaolinite, boehmite, chlorite-group mineral, quartz, calcite, pyrite, siderite and amorphous clay material. Some Li could be absorbed by clay minerals in the Li-bearing coal seam. The chlorite phase?could be?most likely the host for a part of Li. The Yinshan Oldland should be the most possible source of Li of the coal.     

云南宣威羊场煤矿资源潜力评价

羊场煤矿经50年开采,资源近于枯竭。通过地质调查和预测,提供可靠依据,为危机矿山新增储量,延长矿山服务年限。     

淮北平原浅层地下水中铁和锰的空间差异性及影响因素

通过常规和地统计学分析,查明淮北平原浅层地下水中铁锰含量的空间差异性,得出变异函数图符合指数模型,二者都由结构性因素引起。对其空间分布特征进行分析表明,铁、锰在空间呈现相同的分布趋势,超标区主要分布在地势低洼地和低山丘陵区,其含量与岩土成分、地下水所处的氧化还原环境、地下水径流条件、酸碱性等有关。     

淮北煤田太原组灰岩水年龄及同位素地球化学特征

为了解淮北煤田太原组灰岩水年龄、水化学特征及演化,采集了淮北煤田29个矿井地下水样品进行水常规、氢氧同位素及~(14)C测试。利用传统图示及统计方法探讨了地下水化学特征及演化,约束了地下水年龄及径流特征。结果表明:淮北煤田太原组灰岩水年龄在2900～21910 a之间变化,不同矿区之间灰岩水化学特征有明显差异。闸河矿区以较低的TDS浓度、最小的地下水年龄和最高的δD和δ~(18)O值为特征,为淮北煤田太原组灰岩水主要的补给区;临涣矿区孙疃矿、宿县矿区桃园矿具有较大的地下水年龄、较高的TDS浓度和低的δD和δ~(18)O值,为主要排泄区。TDS浓度等值线图和地下水年龄等值线图呈现一致的演化规律,淮北煤田东北部闸河矿区为主要补给区。太原组灰岩水径流特征主要受构造背景的控制,地下水补给条件及水岩相互作用程度决定了水体中TDS浓度和氢氧同位素富集特征。     

淮北煤田煤中常量金属元素特征及其对煤成烃的影响

煤中常量金属元素是煤的重要组成,也是影响煤物理化学性质及加工利用的主要因素。通过测试淮北煤田16个煤样的4种常量金属元素（Fe、Ca、K和Ti）含量,分析其含量和赋存特征,并在此基础上,对去除铁元素的煤样和原煤样进行了热模拟实验。实验结果表明,4种元素含量的变异系数较大,元素来源具有多样性;钾元素主要以无机状态存在,其他元素以无机和有机结合态存在;去除铁元素的煤样热解烃含量的降低幅度较大。     

淮北煤田上石盒子组花斑泥岩中的粘土矿物研究

淮北煤田上石盒子组花斑泥岩中的粘土矿物组合以高岭石为主,伊利石次之。高岭石的结晶度较好。伊利石均表现有混层现象。研究表明,花斑泥岩经历了较强的成岩作用。     

Controlling Factors,Accumulation Model and Target Zone Prediction of the Coal‐bed Methane in the Huanghebei Coalfield,North China

The Huanghebei Coalfield, one of the coal production bases in North China, was considered as a coalfield without coal‐bed methane (CBM) during past decades. In recent years, however, CBM has been discovered in coal‐bearing successions. In order to understand the CBM geological characteristics and accumulation process in this area, fifteen coal samples were collected and analyzed with respect to coal maceral and reflectance. The result shows that the gas distribution is uneven and the content varies in different areas even for the same coal bed. The storage of CBM is affected by geological factors such as burial depth, geological structures, and magmatic intrusion, among which the former two are more important in the formation of CBM. Deep burial of coal beds with the presence of cap‐rock mudstone can seal CBM. The CBM is also accumulated and preserved at the place where normal faults are distributed. Magmatic intrusion causes contact metamorphism and controls the CBM formation by heating the coal‐bearing successions. The obtained data indicate the geological conditions in northeastern Zhaoguan Mine are preferable for CBM formation and conservation; recent exploration estimates the CBM geological reserves up to 282.16 Mm³ and average of reserve abundance at 0.1662 × 10⁸ m³ km^?2. The Changqing Mine is a potential prospect in terms of CBM exploration since its geological conditions (structures and burial depth) are similar to the Zhaoguan Mine and its cap rock is even better.     

淮北矿区煤层气资源勘查潜力评价

淮北矿区地处华东腹地,煤层气资源丰富,具备大规模开发的前景。选用层次分析法与灰色聚类法评价方法,通过构建层次结构模型、计算指标权重、制定参数分类评价标准、运用灰色聚类法判别灰类、计算综合优度值,对矿区16个评价单元的山西组和下石盒子组煤层气资源潜力进行了评价,结果显示,淮北矿区山西组煤层气勘查潜力中等,下石盒子组勘查潜力较好。