The nanocomposite EVAL-CNT was produced by chemical grafting in the solution system through the esterification of ethylene-vinyl alcohol copolymer (EVAL) and carboxylated multi-walled carbon nanotubes (O-MWCNT), and i...The nanocomposite EVAL-CNT was produced by chemical grafting in the solution system through the esterification of ethylene-vinyl alcohol copolymer (EVAL) and carboxylated multi-walled carbon nanotubes (O-MWCNT), and its structural properties were characterized. The improvement of the rheological properties of the waxy oil system by the novel pour point depressant was investigated using macroscopic rheological measurements and microscopic observations. The results showed that EVAL-CNT nanocomposite pour point depressant (PPD) could significantly reduce the pour point and improve the low temperature fluidity of crude oil and had better performance than EVAL-GO at the same addition level. The best effect was achieved at the dosing concentration of 400 ppm, which reduced the pour point by 13 ℃ and the low-temperature viscosity by 85.4%. The nanocomposites dispersed in the oil phase influenced the precipitation and crystallization of wax molecules through heterogeneous crystallization templates, which led to the increase of wax crystal size and compact structure and changed the wax crystal morphology, which had a better effect on the rheological properties of waxy oil.展开更多
The pipeline transportation of waxy crude oil is a problem both at home and abroad.In this paper,a novel nanohybrid pour-point depressant (PPD) was used to decrease the pour point and viscosity of waxy crude oil.The p...The pipeline transportation of waxy crude oil is a problem both at home and abroad.In this paper,a novel nanohybrid pour-point depressant (PPD) was used to decrease the pour point and viscosity of waxy crude oil.The pour point and apparent viscosity of waxy crude oil was decreased significantly upon addition of the nanohybrid PPD,and the long-term stability of the nanohybrid PPD was superior to that of a conventional ethylene-vinyl acetate copolymer PPD.Polarized optical microscopy and X-ray diffraction were used to study the effect of the nanohybrid PPD on the crystallization of crude oil.Addition of the nanohybrid PPD reduced the amount of wax crystals,prevented their aggregation,and reduced the temperature at which the crude oil started to crystallize.The significant effect of this nanohybrid PPD on the pour point and viscosity depressing of crude oil is of great importance for facilitating the safe,efficient and energy-minimized transportation of waxy crude oil.展开更多
In this study,the physicochemical properties of linseed and linseed biofuel were studied and their effect on the flow properties of Nigerian waxy crude oil at different volume fractions was investigated.The Nigerian w...In this study,the physicochemical properties of linseed and linseed biofuel were studied and their effect on the flow properties of Nigerian waxy crude oil at different volume fractions was investigated.The Nigerian wax crude oil was characterized for its specific gravity,API gravity,wax content,pour point and cloud point.The properties of the linseed oil and linseed biodiesel investigated include:density,specific gravity,viscosity,pour point,cloud point and flash point.Upon esterification of the free fatty acid(FFA)contained in the linseed oil reduced from 3.5 to 0.75 and the viscosity of the seed oil reduces from 2169 to 362 mm^(2)/s.The linseed oil and its biodiesel exhibited similar trend of reduced viscosity at higher shear rate,however,linseed biodiesel demonstrated the lowest viscosities,cloud points and pour points owing to reduced fatty contents.The effect of the linseed oil and its biodiesel on the pour point and cloud point of the waxy crude oil was determined;and the performance compared to that of xylene.A rapid drop in the pour point and cloud point was observed with the wax crude pre-heated with 0.1 v/v linseed oil,its biodiesel and xylene.展开更多
文摘The nanocomposite EVAL-CNT was produced by chemical grafting in the solution system through the esterification of ethylene-vinyl alcohol copolymer (EVAL) and carboxylated multi-walled carbon nanotubes (O-MWCNT), and its structural properties were characterized. The improvement of the rheological properties of the waxy oil system by the novel pour point depressant was investigated using macroscopic rheological measurements and microscopic observations. The results showed that EVAL-CNT nanocomposite pour point depressant (PPD) could significantly reduce the pour point and improve the low temperature fluidity of crude oil and had better performance than EVAL-GO at the same addition level. The best effect was achieved at the dosing concentration of 400 ppm, which reduced the pour point by 13 ℃ and the low-temperature viscosity by 85.4%. The nanocomposites dispersed in the oil phase influenced the precipitation and crystallization of wax molecules through heterogeneous crystallization templates, which led to the increase of wax crystal size and compact structure and changed the wax crystal morphology, which had a better effect on the rheological properties of waxy oil.
文摘The pipeline transportation of waxy crude oil is a problem both at home and abroad.In this paper,a novel nanohybrid pour-point depressant (PPD) was used to decrease the pour point and viscosity of waxy crude oil.The pour point and apparent viscosity of waxy crude oil was decreased significantly upon addition of the nanohybrid PPD,and the long-term stability of the nanohybrid PPD was superior to that of a conventional ethylene-vinyl acetate copolymer PPD.Polarized optical microscopy and X-ray diffraction were used to study the effect of the nanohybrid PPD on the crystallization of crude oil.Addition of the nanohybrid PPD reduced the amount of wax crystals,prevented their aggregation,and reduced the temperature at which the crude oil started to crystallize.The significant effect of this nanohybrid PPD on the pour point and viscosity depressing of crude oil is of great importance for facilitating the safe,efficient and energy-minimized transportation of waxy crude oil.
文摘In this study,the physicochemical properties of linseed and linseed biofuel were studied and their effect on the flow properties of Nigerian waxy crude oil at different volume fractions was investigated.The Nigerian wax crude oil was characterized for its specific gravity,API gravity,wax content,pour point and cloud point.The properties of the linseed oil and linseed biodiesel investigated include:density,specific gravity,viscosity,pour point,cloud point and flash point.Upon esterification of the free fatty acid(FFA)contained in the linseed oil reduced from 3.5 to 0.75 and the viscosity of the seed oil reduces from 2169 to 362 mm^(2)/s.The linseed oil and its biodiesel exhibited similar trend of reduced viscosity at higher shear rate,however,linseed biodiesel demonstrated the lowest viscosities,cloud points and pour points owing to reduced fatty contents.The effect of the linseed oil and its biodiesel on the pour point and cloud point of the waxy crude oil was determined;and the performance compared to that of xylene.A rapid drop in the pour point and cloud point was observed with the wax crude pre-heated with 0.1 v/v linseed oil,its biodiesel and xylene.
