Key Laboratory of Oil&Gas Production CNPC Beijing 100083 ChinaResearch Institute of Petroleum Exploration&Development PetroChina Beijing 100083 China;
Oil&Gas Technology Research Institude of Changqing Oil Field Company PetroChina Xi’an 710018 China;
water-yielding gas well; Gemini surfactant; nano-particle; characteristic auxiliaries; foaming agents series; drainage gas recovery;