Experimental study of low-damage drilling fluid to minimize waterblocking of low-permeability gas reservoirs

• Published in: Petroleum science 2009-09, Vol.6 (3), p.271-276
• Main Authors: Zhang, Hongxia, Yan, Jienian, Lu, Yu, Shu, Yong, Zhao, Shengying
• Format: Article
• Language: English
• Subjects: Earth and Environmental Science; Earth Sciences; Economics and Management; Energy Policy; Industrial and Production Engineering; Industrial Chemistry/Chemical Engineering; Mineral Resources; 低渗透油气藏; 内蒙古自治区; 地层损害; 成膜技术; 苏里格气田; 鄂尔多斯盆地; 钻井液
• ISSN: 1672-5107; 1995-8226
• DOI: 10.1007/s12182-009-0043-7

This paper discusses the systematic design and development of low-damage drilling fluid to protect the low-permeability gas reservoir of the Sulige block in the Ordos Basin, Inner Mongolia Autonomous Region, China. Based on investigation of the geological characteristics and the potential formation damage of the Permian formation of the reservoir, waterblocking due to invasion of drilling or completion fluids was identified one of the most severe causes of damage to gas well deliverability. By adopting the phase trap prevention method, ideal packing theory, and film-forming technology, a lowdamage drilling fluid, sodium formate brine containing efficient waterblocking preventing surfactants, optimized temporary bridging agents （TBAs）, and film-forming agents has been developed. The performance of the new drilling fluid was evaluated by using a variety of techniques. The results show that the fluid has good rheological properties, good strong shale-swelling inhibition, good temporary plugging effect, ultra-low filtration, and good lubricity. It can efficiently minimize waterblocking and can be used to drill horizontal wells with minimal intervention of the reservoir in the Sulige Gas Field.