The flow behavior of paper coating is critical to the coating operation. In this work, the influence of the added agents on the flow behavior and the viscoelastic behavior is investigated using rheometer in steady and...The flow behavior of paper coating is critical to the coating operation. In this work, the influence of the added agents on the flow behavior and the viscoelastic behavior is investigated using rheometer in steady and dynamic oscillatory modes.展开更多
The problem of hydrate blockage of pipelines in offshore production is becoming ever-increasing severe because oil fields in ever-increasing unusual environments have been brought in production.HCFC-141b and THF were ...The problem of hydrate blockage of pipelines in offshore production is becoming ever-increasing severe because oil fields in ever-increasing unusual environments have been brought in production.HCFC-141b and THF were selected as the substitutes to study the flow assurance of the hydrates in pipelines.There are critical hydrate volume concentrations for these two slurries.Hydrate slurries behave like Bingham fluids and have high agglomerating tendency when the hydrate volume concentrations are larger than the critical ones.Based on rheological behaviors of these two hydrates,a non-dimensional parameter is proposed through studying the driving forces of agglomeration among hydrate particles,which shows the agglomerating probability of hydrate particles in pipeline and can be used to judge the safety of the pipeline.Moreover,a safe model to judge the safely flow hydrate slurries was presented and verified with the experimental data,which demonstrates that the model is effective to judge whether the pipeline can be run safely or not.展开更多
The flow assurance problem of pipelines in offshore production is becoming more and more serious because oil fields in more and more unusual environments have been brought in production.HCFC-141b and THF were selected...The flow assurance problem of pipelines in offshore production is becoming more and more serious because oil fields in more and more unusual environments have been brought in production.HCFC-141b and THF were selected as the substitutes to study the flow behavior and mechanism of hydrate blockage in pipelines on the newly built flow loop,which was a two pass loop consisting of a 42 mm diameter stainless pipe,30 m long.Slurry-like hydrates and slush-like hydrates were observed with the formation of hydrates in pipeline.There are critical hydrate volume concentrations of 37.5% for HCFC-141b hydrate slurry and 50.6% for THF hydrate slurry respectively.The pipeline would be free of hydrate blockage when the hydrate volume concentration was lower than the critical volume concentration; while otherwise the pipeline would be easily blocked.A safe region,which is defined according the critical hydrate volume concentrations,is firstly proposed for hydrate slurry,and it can be used to judge if the pipeline can be run safely or not.展开更多
文摘The flow behavior of paper coating is critical to the coating operation. In this work, the influence of the added agents on the flow behavior and the viscoelastic behavior is investigated using rheometer in steady and dynamic oscillatory modes.
文摘The problem of hydrate blockage of pipelines in offshore production is becoming ever-increasing severe because oil fields in ever-increasing unusual environments have been brought in production.HCFC-141b and THF were selected as the substitutes to study the flow assurance of the hydrates in pipelines.There are critical hydrate volume concentrations for these two slurries.Hydrate slurries behave like Bingham fluids and have high agglomerating tendency when the hydrate volume concentrations are larger than the critical ones.Based on rheological behaviors of these two hydrates,a non-dimensional parameter is proposed through studying the driving forces of agglomeration among hydrate particles,which shows the agglomerating probability of hydrate particles in pipeline and can be used to judge the safety of the pipeline.Moreover,a safe model to judge the safely flow hydrate slurries was presented and verified with the experimental data,which demonstrates that the model is effective to judge whether the pipeline can be run safely or not.
文摘The flow assurance problem of pipelines in offshore production is becoming more and more serious because oil fields in more and more unusual environments have been brought in production.HCFC-141b and THF were selected as the substitutes to study the flow behavior and mechanism of hydrate blockage in pipelines on the newly built flow loop,which was a two pass loop consisting of a 42 mm diameter stainless pipe,30 m long.Slurry-like hydrates and slush-like hydrates were observed with the formation of hydrates in pipeline.There are critical hydrate volume concentrations of 37.5% for HCFC-141b hydrate slurry and 50.6% for THF hydrate slurry respectively.The pipeline would be free of hydrate blockage when the hydrate volume concentration was lower than the critical volume concentration; while otherwise the pipeline would be easily blocked.A safe region,which is defined according the critical hydrate volume concentrations,is firstly proposed for hydrate slurry,and it can be used to judge if the pipeline can be run safely or not.
