Heavy oil represents a vital petroleum resource worldwide.As one of the major producers,China is facing great challenges in effective and economic production of heavy oil due to reservoir complexity.Plenty of efforts ...Heavy oil represents a vital petroleum resource worldwide.As one of the major producers,China is facing great challenges in effective and economic production of heavy oil due to reservoir complexity.Plenty of efforts have been made to promote innovative advances in thermal recovery modes,methods,and processes for heavy oil in the country.The thermal recovery mode has been shifted from simple steam injection to a more comprehensive“thermal+"strategy,such as a novel N2-steam hybrid process and CO_(2)-enhanced thermal recovery techniques.These advanced techniques break through the challenges of heavy oil extraction from less accessible reservoirs with thinner oil layers and greater burial depths.Regarding thermal recovery methods,China has developed the steam-assisted gravity drainage method integrating flooding and drainage(also referred to as the hybrid flooding-drainage SAGD technology)for highly heterogeneous ultra-heavy oil reservoirs and the fire flooding method for nearly depleted heavy oil reservoirs,substantially improving oil recovery.Furthermore,a range of processes have been developed for heavy oil production,including the open hole completion process using sand control screens for horizontal wells,the process of integrated injection-recovery with horizontal pump for horizontal wells,the steam dryness maintenance,measurement,and control process,efficient and environment-friendly circulating fluidized bed(CFB)boilers with high steam dryness,the recycling process of produced water,and the thermal recovery process for offshore heavy oil.Based on the advances in methodology,technology,and philosophy,a series of supporting technologies for heavy oil production have been developed,leading to the breakthrough of existing technical limit of heavy oil recovery and the expansion into new exploitation targets.For the future heavy oil production in China,it is necessary to embrace a green,low-carbon,and energy-efficient development strategy,and to expand heavy oil extraction in reservoirs with larger burial depth,more viscous oil,thinner oil layers,and lower permeability.Moreover,it is highly recommended to collaboratively maximize oil recovery and oil-to-steam ratio through technological innovations,and boost intelligentization of heavy oil production.展开更多
The technology level of heavy oil thermal re-covery in Liaohe Oilfield is greatly improved after more than ten years of practice,and the technology in Shuguang is symbolic.The annual heavy oil pro-duction in Shuguang ...The technology level of heavy oil thermal re-covery in Liaohe Oilfield is greatly improved after more than ten years of practice,and the technology in Shuguang is symbolic.The annual heavy oil pro-duction in Shuguang has reached 196X 10*t now.展开更多
Light crude oil from the lower member of the Paleogene Xiaganchaigou Formation of Gaskule in Qinghai Oilfield was selected to carry out thermal kinetic analysis experiments and calculate the activation energy during t...Light crude oil from the lower member of the Paleogene Xiaganchaigou Formation of Gaskule in Qinghai Oilfield was selected to carry out thermal kinetic analysis experiments and calculate the activation energy during the oil oxidation process.The oxidation process of crude oi l in porous medium was modeled by crude oil static oxidation experiment,and the component changes of crude oil before and after low-temperature oxidation were compared through Fourier transform ion cy-clotron resonance mass spectrometry and gas chromatography;the dynamic displacement experiment of oxygen-reduced air was combined with NMR technology to analyze the oil recovery degree of oxygen-reduced air flooding.The whole process of crude oil oxidation can be divided into four stages:light hydrocarbon volatilization,low-temperature oxidation,fuel deposition,and high temperature oxidation;the high temperature oxidation stage needs the highest activation energy,followed by the fuel deposition stage,and the low-temperature oxidation stage needs the lowest activation energy;the concentration of oxygen in the reaction is negatively correlated with the activation energy required for the reaction;the higher the oxygen concentration,the lower the average activation energy required for oxidation reaction is;the low-temperature oxidation reaction between crude oil and air generates a large amount of heat and CO,CO_(2) and CH4,forming flue gas drive in the reservoir,which has certain effects of mixing phases,reducing viscosity,lowering interfacial tension and promoting expansion of crude oil,and thus helps enhance the oil recovery rate.Under suitable reservoir temperature condition,the degree of recovery of oxygen-reduced air flooding is higher than that of nitrogen flooding for all scales of pore throat,and the air/oxygen-reduced air flooding de-velopment should be preferred.展开更多
Due to the increased demand for energy resources these days,especially due to the Russian-Ukrainian war,the focus of the major countries is turning strongly towards improving oil production,especially heavy and extra ...Due to the increased demand for energy resources these days,especially due to the Russian-Ukrainian war,the focus of the major countries is turning strongly towards improving oil production,especially heavy and extra heavy oil,which represents 40%of the world oil reserve.Steam-based and thermal(EOR)procedures are promising techniques for recovering heavy oil reservoirs,but they suffer from a sequence of problems and complications that arise after long-term application.These complications comprise steam breakthrough,steam overlap,and steam/rock interactions.This research presents the currently applied techniques to maximize the productivity of heavy oil,such as steam injection,cyclic steam stimulation,in-situ combustion,and steam-assisted gravity drainage.Thermal technologies face numerous obstacles,as they are energy and water-intensive processes that are not environmentally friendly.The research also presents future trends in energy-saving and environmentally friendly techniques that enhance heavy oil recovery through vapor extraction(VAPEX)steam-solvent hybrid techniques,electromagnetic energy,sonication,and nanotechnology.The findings of this review reported that all the presented techniques focus on how to reduce the oil viscosity and in-situ upgrade the crude oil properties.In turn,these enhance both the productivity rate and oil recovery and minimize the production cost.This article can be considered a comprehensive review of thermal recovery methods in heavy and extra-heavy oil,in addition to screening criteria used for each method.展开更多
The investigation on thermodynamic properties (density ρ, viscosity ν) of heavy oil has been carried out in the temperature range 298 - 363 K at pressure 0.098 MPa, and thermal expansion coefficient αp at pressures...The investigation on thermodynamic properties (density ρ, viscosity ν) of heavy oil has been carried out in the temperature range 298 - 363 K at pressure 0.098 MPa, and thermal expansion coefficient αp at pressures up to 49 MPa. The results of specific heat measurements of oil and oil products are presented at pressures up to 29 MPa and temperatures up to 613 K for heavy oil and temperature range of 323 - 473 K at atmospheric pressure for oil products. Thermal effects occurring during the processing of crude oil have been investigated. According to the obtained values of thermal expansion coefficients, density of the oil has been calculated for pressures up to 49 MPa.展开更多
基金funded by a project of the National Natural Science Foundation of China entitled Basic study on mechanisms and key technologies of high efficiency hybrid multi-element thermal recovery in marginal heavy oil reservoirs(No.U20B6003).
文摘Heavy oil represents a vital petroleum resource worldwide.As one of the major producers,China is facing great challenges in effective and economic production of heavy oil due to reservoir complexity.Plenty of efforts have been made to promote innovative advances in thermal recovery modes,methods,and processes for heavy oil in the country.The thermal recovery mode has been shifted from simple steam injection to a more comprehensive“thermal+"strategy,such as a novel N2-steam hybrid process and CO_(2)-enhanced thermal recovery techniques.These advanced techniques break through the challenges of heavy oil extraction from less accessible reservoirs with thinner oil layers and greater burial depths.Regarding thermal recovery methods,China has developed the steam-assisted gravity drainage method integrating flooding and drainage(also referred to as the hybrid flooding-drainage SAGD technology)for highly heterogeneous ultra-heavy oil reservoirs and the fire flooding method for nearly depleted heavy oil reservoirs,substantially improving oil recovery.Furthermore,a range of processes have been developed for heavy oil production,including the open hole completion process using sand control screens for horizontal wells,the process of integrated injection-recovery with horizontal pump for horizontal wells,the steam dryness maintenance,measurement,and control process,efficient and environment-friendly circulating fluidized bed(CFB)boilers with high steam dryness,the recycling process of produced water,and the thermal recovery process for offshore heavy oil.Based on the advances in methodology,technology,and philosophy,a series of supporting technologies for heavy oil production have been developed,leading to the breakthrough of existing technical limit of heavy oil recovery and the expansion into new exploitation targets.For the future heavy oil production in China,it is necessary to embrace a green,low-carbon,and energy-efficient development strategy,and to expand heavy oil extraction in reservoirs with larger burial depth,more viscous oil,thinner oil layers,and lower permeability.Moreover,it is highly recommended to collaboratively maximize oil recovery and oil-to-steam ratio through technological innovations,and boost intelligentization of heavy oil production.
文摘The technology level of heavy oil thermal re-covery in Liaohe Oilfield is greatly improved after more than ten years of practice,and the technology in Shuguang is symbolic.The annual heavy oil pro-duction in Shuguang has reached 196X 10*t now.
文摘Light crude oil from the lower member of the Paleogene Xiaganchaigou Formation of Gaskule in Qinghai Oilfield was selected to carry out thermal kinetic analysis experiments and calculate the activation energy during the oil oxidation process.The oxidation process of crude oi l in porous medium was modeled by crude oil static oxidation experiment,and the component changes of crude oil before and after low-temperature oxidation were compared through Fourier transform ion cy-clotron resonance mass spectrometry and gas chromatography;the dynamic displacement experiment of oxygen-reduced air was combined with NMR technology to analyze the oil recovery degree of oxygen-reduced air flooding.The whole process of crude oil oxidation can be divided into four stages:light hydrocarbon volatilization,low-temperature oxidation,fuel deposition,and high temperature oxidation;the high temperature oxidation stage needs the highest activation energy,followed by the fuel deposition stage,and the low-temperature oxidation stage needs the lowest activation energy;the concentration of oxygen in the reaction is negatively correlated with the activation energy required for the reaction;the higher the oxygen concentration,the lower the average activation energy required for oxidation reaction is;the low-temperature oxidation reaction between crude oil and air generates a large amount of heat and CO,CO_(2) and CH4,forming flue gas drive in the reservoir,which has certain effects of mixing phases,reducing viscosity,lowering interfacial tension and promoting expansion of crude oil,and thus helps enhance the oil recovery rate.Under suitable reservoir temperature condition,the degree of recovery of oxygen-reduced air flooding is higher than that of nitrogen flooding for all scales of pore throat,and the air/oxygen-reduced air flooding de-velopment should be preferred.
文摘Due to the increased demand for energy resources these days,especially due to the Russian-Ukrainian war,the focus of the major countries is turning strongly towards improving oil production,especially heavy and extra heavy oil,which represents 40%of the world oil reserve.Steam-based and thermal(EOR)procedures are promising techniques for recovering heavy oil reservoirs,but they suffer from a sequence of problems and complications that arise after long-term application.These complications comprise steam breakthrough,steam overlap,and steam/rock interactions.This research presents the currently applied techniques to maximize the productivity of heavy oil,such as steam injection,cyclic steam stimulation,in-situ combustion,and steam-assisted gravity drainage.Thermal technologies face numerous obstacles,as they are energy and water-intensive processes that are not environmentally friendly.The research also presents future trends in energy-saving and environmentally friendly techniques that enhance heavy oil recovery through vapor extraction(VAPEX)steam-solvent hybrid techniques,electromagnetic energy,sonication,and nanotechnology.The findings of this review reported that all the presented techniques focus on how to reduce the oil viscosity and in-situ upgrade the crude oil properties.In turn,these enhance both the productivity rate and oil recovery and minimize the production cost.This article can be considered a comprehensive review of thermal recovery methods in heavy and extra-heavy oil,in addition to screening criteria used for each method.
文摘The investigation on thermodynamic properties (density ρ, viscosity ν) of heavy oil has been carried out in the temperature range 298 - 363 K at pressure 0.098 MPa, and thermal expansion coefficient αp at pressures up to 49 MPa. The results of specific heat measurements of oil and oil products are presented at pressures up to 29 MPa and temperatures up to 613 K for heavy oil and temperature range of 323 - 473 K at atmospheric pressure for oil products. Thermal effects occurring during the processing of crude oil have been investigated. According to the obtained values of thermal expansion coefficients, density of the oil has been calculated for pressures up to 49 MPa.
