摘要 :
The objective of this paper is studying the impact of the hydraulic flow unit and reservoir quality index(RQI)on pressure profile and productivity index of horizontal wells acting in finite reservoirs.Several mathematical models h...
展开
The objective of this paper is studying the impact of the hydraulic flow unit and reservoir quality index(RQI)on pressure profile and productivity index of horizontal wells acting in finite reservoirs.Several mathematical models have been developed to investigate this impact.These models have been built based on the pressure distribution in porous media,depleted by a horizontal well,consist of multi hydraulic flow units and different reservoir quality index.The porous media are assumed to be finite rectangular reservoirs having different configurations and the wellbores may have different lengths.Several analytical models describing flow regimes have been derived wherein hydraulic flow units and reservoir quality index have been included in addition to rock and fluid properties.The impact of these two parameters on reservoir performance has also been studied using steady state productivity index.It has been found that both pressure responses and flow regimes are highly affected by the existence of multiple hydraulic flow units in the porous media and the change in reservoir quality index for these units.Positive change in the RQI could lead to positive change in both pressure drop required for reservoir fluids to move towards the wellbore and hence the productivity index.
收起
摘要 :
Air injection in light oil reservoirs has received considerable attention as an effective,improved oil recovery process,based primarily on the success of several projects within the Williston Basin in the United States.The main me...
展开
Air injection in light oil reservoirs has received considerable attention as an effective,improved oil recovery process,based primarily on the success of several projects within the Williston Basin in the United States.The main mechanism of air injection is the oxidation behavior between oxygen and crude oil in the reservoir.Air injection is a good option because of its wide availability and low cost.Whether air injection can be applied to shale is an interesting topic from both economic and technical perspectives.This paper initiates a comprehensive discussion on the feasibility and potential of air injection in shale oil reservoirs based on state-of-the-art literature review.Favorable and unfavorable effects of using air injection are discussed in an analogy analysis on geology,reservoir features,temperature,pressure,and petrophysical,mineral and crude oil properties of shale oil reservoirs.The available data comparison of the historically successful air injection projects with typical shale oil reservoirs in the U.S.is summarized in this paper.Some operation methods to improve air injection performance are recommended.This paper provides an avenue for us to make use of many of the favorable conditions of shale oil reservoirs for implementing air injection,or air huff‘n’puff injection,and the low cost of air has the potential to improve oil recovery in shale oil reservoirs.This analysis may stimulate further investigation.
收起
摘要 :
Natural gas hydrate is widely distributed in continental slope sediments and permafrost,taken as a potential energy resource due to its gigantic amount.To develop the technologies for the industrial exploitation of natural gas hyd...
展开
Natural gas hydrate is widely distributed in continental slope sediments and permafrost,taken as a potential energy resource due to its gigantic amount.To develop the technologies for the industrial exploitation of natural gas hydrate,several production tests were carried out in permafrost and marine hydrate reservoirs,e.g.tests in permafrost hydrate reservoirs in Mackenzie Delta and Alaskan North Slope(Boswell et al.,2017)in the Antarctic,and those in marine hydrate reservoirs in Nankai Trough,offshore Japan(Yamamoto et al.,2014,2018),and South China Sea(SCS)(Li et al.,2018;Ye et al.,2020).As encouraged by the results obtained from the production tests,more tests are planned to develop technology for industrial exploitation of natural gas hydrate(Collett et al.,2022).Although production test can be conducted in permafrost hydrate reservoir for cost efficiency,generally it is thought industrial exploitation will be realized in marine hydrate reservoir because it is estimated with over 90%of hydrate resource.
收起
摘要 :
Human immunodeficiency virus-1(HIV)reservoirs in the human brain:Antiretroviral therapy(ART)effectively decreases active HIV replication to undetectable levels.Therefore,it greatly improves the quality of life for people living with HIV(PLWH).
摘要 :
Coalbed methane has been explored in many basins worldwide for 30 years, and has been developed commercially in some of the basins. Many researchers have described the characteristics of coalbed methane geology and technology syst...
展开
Coalbed methane has been explored in many basins worldwide for 30 years, and has been developed commercially in some of the basins. Many researchers have described the characteristics of coalbed methane geology and technology systematically. According to these investigations, a coalbed methane reservoir can be defined: "a coal seam that contains some coalbed methane and is isolated from other fluid units is called a coalbed methane reservoir".On the basis of anatomizafion, analysis, and comparison of the typical coalbed methane reservoirs, coalbed methane reservoirs can be divided into two classes: the hydrodynamic sealing coalbed methane reservoirs and the self-sealing coalbed methane reservoirs. The former can be further divided into two sub-classes: the hydrodynamic capping coalbed methane reservoirs, which can be divided into five types and the hydrodynamic driving coalbed methane reservoirs,which can be divided into three types. The latter can be divided into three types. Currently, hydrodynamic sealing reservoirs are the main target for coalbed methane exploration and development; self-sealing reservoirs are unsuitable for coalbed methane exploration and development, but they are closely related with coal mine gas hazards. Finally, a model for hydrodynamic sealing coalbed methane reservoirs is established.
收起
摘要 :
So far, more than 150 marine oil-gas fields have been found onshore and offshore about 350.The marine source rocks are mainly Paleozoic and Mesozoic onshore whereas Tertiary offshore. Three genetic categories of oil-gas reservoirs...
展开
So far, more than 150 marine oil-gas fields have been found onshore and offshore about 350.The marine source rocks are mainly Paleozoic and Mesozoic onshore whereas Tertiary offshore. Three genetic categories of oil-gas reservoirs have been defined for the marine reservoirs in China: primary reservoirs, secondary reservoirs and hydrocarbon-regeneration reservoirs. And three exploration prospects have also been suggested: (1) Primary reservoirs prospects, which are chiefly distributed in many Tertiary basins of the South China Sea (SCS), the Tertiary shelf basins of the East China Sea (ECS) and the Paleozoic of Tarim basin, Sichuan basin and Ordos basin. To explore large-middle-scale even giant oil-gas fields should chiefly be considered in this category reservoirs. These basins are the most hopeful areas to explore marine oil-gas fields in China, among which especially many Tertiary basins of the SCS should be strengthened to explore. (2) Secondary reservoirs prospects, which are mainly distributed in the Paleozoic and Mesozoic of the Tarim basin, Sichuan basin, Qiangtang basin and Chuxiong basin in western China, of which exploration potential is less than that of the primary reservoirs. (3) Hydrocarbon-regeneration reservoirs prospects, which are chiefly distributed in the Bohai Bay basin, North Jiangsu-South Yellow Sea basin, southern North China basin, Jianghan basin,South Poyang basin in eastern China and the Tarim basin in western China, of which source rocks are generally the Paleozoic. And the reservoirs formed by late-stage (always Cenozoic) secondary hydrocarbon generation of the Paleozoic source rocks should mainly be considered to explore, among which middle-small and small oil-gas fields are the chief exploration targets. As a result of higher thermal evolution of Paleozoic and Mesozoic source rocks, the marine reservoirs onshore are mainly gas fields, and so far marine oil fields have only been found in the Tarim basin. No other than establishing corresponding marine oil-gas exploration and development strategy and policy,sufficiently enhancing cognition to the particularity and complexity of China's marine petroleum geology, and applying new thoughts, new theories and new technologies, at the same time tackling some key technologies, it is possible to fast and effectually exploit and utilize the potential huge marine oil-gas resources of China.
收起
摘要 :
Capacity depletion is an important information required for planning of multipurpose reservoirs. It is a complex phenomenon involving diverse fields like surface hydrology, sediment transport, varied flow hydraulics and soil conso...
展开
Capacity depletion is an important information required for planning of multipurpose reservoirs. It is a complex phenomenon involving diverse fields like surface hydrology, sediment transport, varied flow hydraulics and soil consolidation. Proper assessment of capacity reduction is helpful in ascertaining the life of the reservoir and the project benefits for cost/benefit analysis. In this study dimensionally consistent equations for deposition volume and the trap efficiency have been obtained. Methods of obtaining the parameters involved these equations have also been indicated. It was found that there is good agreement with the field data. It is hoped that the equations are useful to design engineer.
收起
摘要 :
Due to the continuous water percolation and soaking during development of the oilfields, the dynamic balance of a reservoir is altered by the fluid; and the rock framework, pores and throats will be reformed and destroyed. The int...
展开
Due to the continuous water percolation and soaking during development of the oilfields, the dynamic balance of a reservoir is altered by the fluid; and the rock framework, pores and throats will be reformed and destroyed. The interaction between the fluid and the rock leads to a series of micro geological processes, such as clastation, denudation, dissolution and deposition, in the small spaces connected by pores or throats, which control the accumulation and distribution of the remaining oil. These micro geological processes are the essential factors for the evolution of the reservoirs during development. This evolution makes the recovery of the remaining oil more complex.
收起
摘要 :
Marine reservoirs are mainly made up of clastics and carbonate reservoirs, which are distributed widely in central Tarim, Sichuan, Ordos basins from the Pre-Cambrian to Cenozoic, mainly in Palaeozoic. Marine clastic reservoirs are...
展开
Marine reservoirs are mainly made up of clastics and carbonate reservoirs, which are distributed widely in central Tarim, Sichuan, Ordos basins from the Pre-Cambrian to Cenozoic, mainly in Palaeozoic. Marine clastic reservoirs are developed in foreshore and nearshore, tidal flat and delta environment. The sedimentary facies are important controlling factors for reservoir quality. Compaction, pressolution and cementation are factors of decreasing porosity, and low palaeo-temperature gradient, early emplacement of oil and gas and dissolution are favorable for preservation of pore. Carbonate reservoirs are divided into reef and bank, karst, dolomite and fracture reservoirs. Dolomitization, dissolution, TSR and fracture are important factors of controlling carbonate reservoirs' quality.
收起
