论文部分内容阅读
许多砂岩和灰岩地层都含有大量的水敏性粘土。这些粘土接触到未处理的水时,可能膨胀,减小流通尺寸,降低渗透性。微粒泄出、运移、小孔隙通道堵塞。水也能软化地层,并能降低生成支撑裂缝的流动能力。 压裂水可用某些盐水处理,以减弱粘土的膨胀。为此目的,也曾用有机聚合物成功地处理过水,水敏性极严重的地层曾使用泡沫、醇类和油基液。给出的实例说明,这些化学剂和基液已成功地用于裂隙水敏性地层。 当有岩心时,基液参数的选择应以室内岩心试验和现场结果为依据。 防滤失添加剂用量的选择,即使在低渗透地层中也是很重要的。加与不加防滤失添加剂的岩心滤失试验对比,说明了在这些地层中使用添加剂的重要性。文中做了一些比较。 支撑剂及其所需浓度的选择,可按裂缝流动能力和算出的支撑裂缝几阿尺寸来确定。计算机程序可用于计算支撑裂缝的几何尺寸。 为了得到更好的增产结果,本文针对压裂低渗透水敏性地层,提利用适当工艺、原料和技术的见解。
Many sandstone and limestone formations contain large amounts of water-sensitive clays. When these clays come into contact with untreated water, they may swell, reducing the size of the flow and decreasing the permeability. Particles leak, migration, small pore channel blockage. Water also softens the formation and reduces the flow ability to create support fractures. Fracturing water can be treated with some brine to reduce the swelling of the clay. To this end, over-water has also been successfully treated with organic polymers, and foams, alcohols and oil-based fluids have been used in very water-sensitive formations. The examples given illustrate that these chemicals and base fluids have been successfully used in fractured water-sensitive formations. When cores are present, the choice of base fluid parameters should be based on laboratory core tests and field results. The choice of anti-slip additive dosage is important even in low permeability formations. The comparison of core filtration tests with and without anti-slip additives shows the importance of using additives in these formations. The text made some comparison. The choice of proppant and its desired concentration can be determined by the fracture flow capacity and the calculated fracture size. Computer programs can be used to calculate the geometry of the support crack. In order to get a better stimulation result, this paper aims at fracturing low-permeability and water-sensitive formations and using the insights of appropriate processes, materials and technologies.