Three-dimensional graphene-based aerogels have promising applications in oil adsorption and environmental restoration.However,current research of graphene-based aerogels is often hindered by high preparation cost,poor...Three-dimensional graphene-based aerogels have promising applications in oil adsorption and environmental restoration.However,current research of graphene-based aerogels is often hindered by high preparation cost,poor mechanical properties and low recycling efficiency.Here,superelastic graphene aerogel(SGA)was prepared through one-step freezing and twice hydrothermal reduction followed by drying under ambient pressure.The simple atmospheric drying provides a possibility for large-scale preparation of high performance graphene-based aerogels.The prepared SGA not only has the ability of highly repeatable compression rebound,but also exhibits excellent oil adsorption performance.And the overall performance of SGA is better than most of graphenebased aerogels prepared by freeze drying.After the SGA was cyclically compressed with 70%strain for 300 times,it can return to the original shape and height substantially.SGA retained about 90%of the initial adsorption capacity after 50 cycles of adsorption and compression regeneration for cyclohexane.展开更多
为了解决高温高压天然气井管柱泄漏问题,国内油气田使用了多种特殊螺纹油套管,但井筒密封性仍然无法得到保障。现行的接头密封面接触压应力设计法不能有效堵塞密封结构的泄漏通道,亟待研究发展石油专用管密封设计方法和密封技术。为此,...为了解决高温高压天然气井管柱泄漏问题,国内油气田使用了多种特殊螺纹油套管,但井筒密封性仍然无法得到保障。现行的接头密封面接触压应力设计法不能有效堵塞密封结构的泄漏通道,亟待研究发展石油专用管密封设计方法和密封技术。为此,在密封面压应力设计基础上,提出增加弹性应变设计,并实验验证技术有效性。研究结果表明:①采用弹性材料实现弹性应变密封设计,通过材料的应力应变循环试验,优选出弹性应变达到6%的超弹性合金Ti-Ni-X;②设计的多种密封结构使密封面产生足够大弹性应变,以堵塞接头在工厂制造或井下服役期间形成的泄漏通道;③研发出一种密封环超弹性应变密封套管,样品成功通过了上卸扣试验和API RP 5C5 CAL IV级B系列密封试验,最大试验载荷达到了95%管体应力包罗线,最大试验温度达到180℃。结论认为,超弹性应变密封新技术可作为新一代石油专用管及井口管件密封的技术储备,该技术有望提高气井管柱和井口管件的密封性。展开更多
基金the financial support of National Natural Science Foundation of China (22078366)
文摘Three-dimensional graphene-based aerogels have promising applications in oil adsorption and environmental restoration.However,current research of graphene-based aerogels is often hindered by high preparation cost,poor mechanical properties and low recycling efficiency.Here,superelastic graphene aerogel(SGA)was prepared through one-step freezing and twice hydrothermal reduction followed by drying under ambient pressure.The simple atmospheric drying provides a possibility for large-scale preparation of high performance graphene-based aerogels.The prepared SGA not only has the ability of highly repeatable compression rebound,but also exhibits excellent oil adsorption performance.And the overall performance of SGA is better than most of graphenebased aerogels prepared by freeze drying.After the SGA was cyclically compressed with 70%strain for 300 times,it can return to the original shape and height substantially.SGA retained about 90%of the initial adsorption capacity after 50 cycles of adsorption and compression regeneration for cyclohexane.
文摘为了解决高温高压天然气井管柱泄漏问题,国内油气田使用了多种特殊螺纹油套管,但井筒密封性仍然无法得到保障。现行的接头密封面接触压应力设计法不能有效堵塞密封结构的泄漏通道,亟待研究发展石油专用管密封设计方法和密封技术。为此,在密封面压应力设计基础上,提出增加弹性应变设计,并实验验证技术有效性。研究结果表明:①采用弹性材料实现弹性应变密封设计,通过材料的应力应变循环试验,优选出弹性应变达到6%的超弹性合金Ti-Ni-X;②设计的多种密封结构使密封面产生足够大弹性应变,以堵塞接头在工厂制造或井下服役期间形成的泄漏通道;③研发出一种密封环超弹性应变密封套管,样品成功通过了上卸扣试验和API RP 5C5 CAL IV级B系列密封试验,最大试验载荷达到了95%管体应力包罗线,最大试验温度达到180℃。结论认为,超弹性应变密封新技术可作为新一代石油专用管及井口管件密封的技术储备,该技术有望提高气井管柱和井口管件的密封性。
