Images obtained via computer tomography perfusion(CTP) technology, a non-invasive functional imaging method, can reflect the hemodynamic status and function of the liver. Images obtained via CTP imaging technology can...Images obtained via computer tomography perfusion(CTP) technology, a non-invasive functional imaging method, can reflect the hemodynamic status and function of the liver. Images obtained via CTP imaging technology can be quantitatively analyzed. The fundamentals, examination, and analysis of CTP images are reviewed in this paper. In addition, this paper provides a review of normal liver CTP imaging, CTP research status, and future developments in the CTP imaging of hepatitis and liver cirrhosis.展开更多
For low-permeability sandstone reservoir with big channel, we researched the novel deep profile method alternative injection of anionic and cationic polymer. Evaluating various factors on adsorption capacity through l...For low-permeability sandstone reservoir with big channel, we researched the novel deep profile method alternative injection of anionic and cationic polymer. Evaluating various factors on adsorption capacity through lab test, the results show that with the increase of temperature, the adsorption capacity decreases and the cationic polymer is easier to be absorbed. With the increase of salinity, adsorption time or polymer concentration, the adsorption capacity increases. The adsorption equilibrium concentration of cationic polymer is 1500 mg/L;adsorption equilibrium time is 8 h. The adsorption equilibrium concentration of anionic polymer is 1000 mg/L;adsorption equilibrium time is 6 h. Physical simulation experiment shows that alternative injection of anionic and cationic polymer is better than injection of single polymer, and preferential injection of cationic polymer is better than preferential injection of anionic polymer. With the increase of injection rounds, sealing capacity gets better, but in view of cost, the rounds should not be more than 3. The profile control technique can obviously enhanced oil recovery, and water displacement recovery increases 41%. 2 wells were tested successfully in Henan Oilfield in June 2010. Approximate 154.47 tons of incremental oil was obtained with 2% water-cut decrease.展开更多
Currently,water injection is widely used for oil field developments.For reservoirs with complex geological structures,large stratigraphic dip angles,low porosities and extra-low permeabilities,the effect of water inje...Currently,water injection is widely used for oil field developments.For reservoirs with complex geological structures,large stratigraphic dip angles,low porosities and extra-low permeabilities,the effect of water injection is not satisfying.This paper establishes a modified radial flow formula on the dip angle,and uses the plane radial seepage theory to get formation pressure distributions and a production formula in tilted strata.For injectors with their threshold pressures greater than their formation in-situ pressures,the effective radius for waterflooding is derived for a given injection pressure and then it is used to evaluate waterflooding effect and well pattern suitability,and guide the oilfield production.This method can also be applied to other waterflooding oilfields with similar geological conditions.展开更多
文摘Images obtained via computer tomography perfusion(CTP) technology, a non-invasive functional imaging method, can reflect the hemodynamic status and function of the liver. Images obtained via CTP imaging technology can be quantitatively analyzed. The fundamentals, examination, and analysis of CTP images are reviewed in this paper. In addition, this paper provides a review of normal liver CTP imaging, CTP research status, and future developments in the CTP imaging of hepatitis and liver cirrhosis.
文摘For low-permeability sandstone reservoir with big channel, we researched the novel deep profile method alternative injection of anionic and cationic polymer. Evaluating various factors on adsorption capacity through lab test, the results show that with the increase of temperature, the adsorption capacity decreases and the cationic polymer is easier to be absorbed. With the increase of salinity, adsorption time or polymer concentration, the adsorption capacity increases. The adsorption equilibrium concentration of cationic polymer is 1500 mg/L;adsorption equilibrium time is 8 h. The adsorption equilibrium concentration of anionic polymer is 1000 mg/L;adsorption equilibrium time is 6 h. Physical simulation experiment shows that alternative injection of anionic and cationic polymer is better than injection of single polymer, and preferential injection of cationic polymer is better than preferential injection of anionic polymer. With the increase of injection rounds, sealing capacity gets better, but in view of cost, the rounds should not be more than 3. The profile control technique can obviously enhanced oil recovery, and water displacement recovery increases 41%. 2 wells were tested successfully in Henan Oilfield in June 2010. Approximate 154.47 tons of incremental oil was obtained with 2% water-cut decrease.
基金This work has been funded by the national science and technology major projects:New Technology for High Efficiency Development of OffshoreHeavy Oil(serial number:2011ZX05024-004the Comprehensive research of limited company:Research on The Chemical Flooding Technology of Multi-layer Heavy Oil Reservoir(serial number:YXKY-2014-ZY-03).
文摘Currently,water injection is widely used for oil field developments.For reservoirs with complex geological structures,large stratigraphic dip angles,low porosities and extra-low permeabilities,the effect of water injection is not satisfying.This paper establishes a modified radial flow formula on the dip angle,and uses the plane radial seepage theory to get formation pressure distributions and a production formula in tilted strata.For injectors with their threshold pressures greater than their formation in-situ pressures,the effective radius for waterflooding is derived for a given injection pressure and then it is used to evaluate waterflooding effect and well pattern suitability,and guide the oilfield production.This method can also be applied to other waterflooding oilfields with similar geological conditions.
