为了解张湾井田3煤层的基本特征和探讨其成煤环境，运用光学显微镜及显微光度计和煤质分析等技术方法，对采自张湾井田3煤层的114件煤样开展了煤的煤岩学分析、工业分析和元素分析。煤的煤岩组分结果表明，煤岩类型主要为半亮型煤，煤层以有机组分为主(总含量大于85.40%)，且均以镜质组为主，次为惰质组，另有少量半镜质组和壳质组；无机组分为黏土类矿物，次为氧化物、少量硫化物和碳酸盐类矿物。煤的最大反射率在0.77%～1.21%。工业分析结果表明：张湾井田3上煤层具有特低全水分(SLM)(0.45%～4.91%)、低灰分(LA)(5.35%～16.52%)、中等-中高挥发分(MV-MHV)(27.62%～36.96%)、低-中等固定碳(LFC-MFC)(44.96%～63.31%)、低硫(LS)(0.19%～0.92%)、低磷-中磷(P-2-P-3)(0.006%～0.076%)、中强-特强黏结(ZQNM-TQNM)(48～100)和高发热量(HQ)(22.25～32.49 MJ/kg)特征；3下煤层具有特低全水分(SLM)(0.55%～2.32%)、低灰分(LA)(5.21%～12.76%)、中等-中高挥发分(MV—MHV)(27.45%～36.95%)、低-中等固定碳(LFC-MFC)(52.74%～63.68%)、低硫(LS)(0.25%～0.84%)、特低磷-低磷(P-1-P-2)(0.004%～0.024%)、强-特强黏结(QNM-TQNM)(76～98)和高发热量(HQ)(25.21～32.05 MJ/kg)特征。张湾井田3煤层煤类主要以1/3焦煤和焦煤为主，另有少量肥煤；煤的工业利用方向为炼焦用煤和动力用煤。张湾3煤层的镜惰比(V/I)值介于1.6～2.7，说明其成煤环境为以潮湿覆水环境起到主导作用；3上煤层的灰成分指数0.12～0.54，3下煤层的灰成分指数0.09～0.41，表明3煤层属受海水影响的沼泽环境； 3煤层硫分均小于1%，表明其成煤环境为海水影响较弱的三角洲成煤环境，3煤层有机硫占全硫比为40.22%～66.20%，表明3煤层应为形成于陆相山前平原的低硫煤； 3煤层所有样品V/(V+Ni)值处在0.215～1.0，V/Cr值为1.06～3.2，Ni/Co值0.57～2.77，均显示还原性较强的沉积环境。张湾井田3煤层沉积环境为淡水还原环境，间或受到海水的影响，为三角洲平原亚相沉积。

To understand the basic characteristics of coals from the No.3 coal seams in the Zhangwan minefield and discuss its coal-forming environment, coal petrology analysis, industrial analysis and element analysis were carried out on 114 coal samples by means of optical microscopy, microscopic photometer and coal quality analysis. The results of coal petrographic composition show that the coal rock type is mainly semi-bright briquette, and the coal seams are dominated by organic components (total content is more than 85.40%). The vitrinite is the main component, followed by inertinite, and a small amount of semi-vitrinite and crust. The inorganic components are clay minerals, followed by oxides, a small amount of sulfides and carbonate minerals. The maximum reflectivity of coal ranges from 0.77% to 1.21%. Industrial analysis results show that the upper coal seam of the No.3 coal seams in the Zhangwan minefield has extra-low total moisture contents (SLM) (0.45%-4.91%), low ash contents (LA) (5.35%-16.52%), medium to medium-high volatile contents (MV-MHV) (27.62%-36.96%), low to medium fixed carbon contents (LFC-MFC) (44.96%-63.31%), low sulfur contents (LS) (0.19%-0.92%), low to medium phosphorus contents (P-2 to P-3)(0.006 6%-0.007 6%), moderate to strong bonding (ZQNM-TQNM) (48-100) and characteristics of high calorific value (HQ) (22.25-32.49 MJ/kg). The lower coal seam of the No.3 coal seam in the Zhangwan minefield has extremely low total moisture contents (SLM) (0.55%-2.32%), low ash contents (LA) (5.21%-12.76%), medium-medium-high volatile contents (MV-MHV) (27.45%-36.95%), medium-medium fixed carbon contents (LFC-MFC) (52.74%-63.68%), low sulfur contents (LS) (0.25%-0.84%), extra-low to low phosphorus (P-1 to P-2) (0.004%-0.024%), strong to super-strong bonding (QNM-TQNM) (76-98) and high calorific value (HQ) (25.21-32.05 MJ/kg) Characteristics. Coal of the No.3 coal seams in the Zhangwan minefield mainly consist of 1/3 coking coal and coking coal, and a small amount of fat coal. The industrial utilization direction of coal are coking coal and power coal. The mirror inertness ratio (V/I) of Zhangwan No.3 coal seam is between 1.6 and 2.7, which indicates that the coal forming environment is dominated by wet overlying water environment; the ash composition index of upper coal seam 3 is 0.12-0.54, and that of lower coal seam 3 is 0.09-0.41, which indicates that coal seam 3 belongs to swampy environment affected by seawater; The sulfur content of No.3 coal seam is less than 1%, indicating that the coal forming environment is delta coal forming environment with weak influence of seawater. The proportion of organic sulfur in total sulfur of coal seam 3 is 40.22%-66.20%, which indicates that coal seam 3 should be low sulfur coal formed in continental Piedmont plain; all samples of coal seam 3 have V/(V+Ni) values of 0.215-1.0, V/Cr values of 1.06-3.2, and Ni/Co values of 0.57-2.77, all of which show the sedimentary environment with strong reduction. The sedimentary environment of No.3 Coal Seam in Zhangwan coalfield is a freshwater reduction environment, occasionally affected by seawater, which is delta plain subfacies.