基于黔西比德—三塘盆地12口煤层气井产出水样品的常规离子测试,揭示该区产出水离子动态特征及其对产能与层间干扰的指示意义:基于R型聚类分析,对离子类别进行了分类并探讨了其意义;比德向斜Z-6,Z-7,Z-10井为压裂液污染井,C1-,Na+,Br-浓度呈异常高特点;随排采的进行,K+,Ca2+,Mg2+,Si4+等离子浓度呈增加趋势,SO42-呈降低趋势,反映产出水封闭性增强;提取Cl-+Na+离子浓度作为判识合排井层间干扰程度与产能效果的典型指标,高产井介于833.18～1 768.26 mg/L,平均1 321.55 mg/L,低产井介于259.22 ～519.4 mg/L,平均380.72 mg/L,高产井产出水Cl-+Na+离子浓度显著高于低产井,阈值介于600 ～ 800 mg/L,揭示产出水封闭性越强,越有利于煤层气高产,初步建立了基于产出水Cl-,Na+离子浓度的多层合排井层间干扰判识模板.结合排采层位,上部含气系统与中、下部含气系统共采兼容性差,建议今后优先开发中、下部含气系统.%Based on the R cluster analysis,ions are classified and their meaning are discussed.The Z-6,Z-7,Z-10 well in Bide syncline are fracturing fluid pollution wells,with exceptionally high Cl-,Na+ and Br-concentrations.As drainage proceeds,the concentrations of K+,Ca2+,Mg2+,Si4+ present an increasing trend while SO42-presents a decreasing trend,which reveals the closure degree of produced water becomes higher.Cl-+Na+ concentration is extracted as a typical index for discriminating the interlayer interference degree and productivity effect of commingling wells,with high production well ranging 833.18-1 768.26 mg/L and averages 1 321.55 mg/L,low production well ranging 259.22-519.4 mg/L and averages 380.72 mg/L.High production well has higher Cl-+Na+ concentration in produced water than low production well,and the threshold value ranges 600-800 mg/L.High closure degree produced water are corresponding to high CBM production.The interlayer interference discrimination template for CBM commingling wells based on Cl-and Na+ concentrations in produced water is established,preliminarily.Considering the drainage layers,the upper CBM system has poor joint mining compatibility with middle and lower CBM systems,and the middle and lower CBM systems should be regarded as a priority for development in the future.
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