石油英语实用

会计学1石油英语实用石油英语实用Chapter Six Petroleum ProductionProduction may be considered as that section of the oil industry concerned with conveying（传送）hydrocarbons（烃）from the reservoir（油藏）to surface,and the separation（分离）of oil,gas,water,and solids to the extent necessary to provide a saleable primary product（初级产品）such as crude oil,NGL(natural gas liquids),and gas.第1页/共36页Producing oil is an intricate（复杂的）art.Oil can be pumped out of the sponge rock（海绵状岩体）at a certain maximum（最大的）rate,determined by the viscosity（粘稠度）of the oil and the quality（质量）of the reservoir.Oil production must be managed carefully to avoid clogging（堵塞）or collapsing（跨塌）the pores（孔隙）,which can prevent a well from accessing（获取）much of the reservoir.Pumping too fast,pumping too slowly or interrupting（间歇式的）production can all damage an oilfield.And not only one but many wells must be drilled to fully exploit（开发）the reservoir,raising the expense（费用）of production.第2页/共36页Drilling curved（斜的）and horizontal（水平的）wells into reservoirs is a common technique to increase production.Another technique involves fracturing（压裂）the reservoir rock by pumping fluids and sand into it under high pressure.The fluids open cracks（裂隙）,and the sand keeps them open to let out the petroleum.This can overcome low permeability（渗透率）.Treating the wellbore（井筒）with various acids（酸）or solvents（溶剂）can also raise permeability.This technique is called acidizing（酸化）.第3页/共36页One of the most commonly uses methods of fracturing is hydraulic fracturing（水力压裂）.Hydraulic fracturing may be defined as the process of creating a facture（裂缝）or fracture system（裂缝系统）in a porous medium（孔隙介质）by injecting a fluid under pressure through a well bore in order to overcome native stresses（天然压力）and to cause material failure（岩石破裂）of the porous medium（孔隙介质）.Briefly it is the creation（形成）and preservation（保持）of a fracture in a reservoir rock（储集岩）.To fracture a reservoir rock,energy must be generated by injecting a fluid down a well and into the formation（地层）.第4页/共36页Reservoir Production Mechanisms（机理）（机理）The production mechanisms which owe their existence to these sources of energy are referred to as“water drive”（水驱）,“solution gas drive”(or“depletion drive”)（溶解气驱）,and“gas cap drive”（气顶驱）respectively.The natural drainage of the oil through the reservoir rock under its own gravity（重力）provides a further production mechanism.A combination of drive mechanisms may operate in the same reservoir.Generally,however,one system will dominate（占支配地位）the others and the relative importance of these will change with time during the production of oil and for this reason it is convenient to consider each type of drive mechanism separately and care must be taken during the development of an oil field to use the reservoir drive pressures to their maximum extent（最大程度）.第5页/共36页Water drive（水驱）:reservoirs drive their energy from water below the oil.Water sweeps the oil up and into the wells.Water drive(edge-water drive)is considered to be the most effective recovery mechanism of all.In order to enable this mechanism to function at its maximum effectiveness（最大程度上发挥作用）,it may be necessary to limit（控制）the rate of oil production so that the aquifer water（淡水）can enter the vacated（腾出空隙的）section of the oil-bearing zone as fast as the oil is withdrawn.第6页/共36页If the oil production rate exceeds（超过）this limit there will be a decline（下降）in the reservoir pressure and a consequent reduction（相应地降低）in the energy available to produce the oil.第7页/共36页Solution gas drive（溶解气驱）(dissolved gas drive or depletion drive)is caused by gas dissolved in the oil.In the subsurface（地下）,the oil is under high pressure.The higher the pressure,the more gas that can be dissolved in the oil.When a well is drilled into the oil reservoir,pressure is relieved（缓解）and gas bubbles（气泡）form in the oil.第8页/共36页Expanding gas bubbles（气泡膨胀）force the oil into the well.Dissolved gas drive is very inefficient,producing only from 10%to 30%of the oil in place（地质储量）,leaving the rest in the reservoir.第9页/共36页Gas cap drive（气顶驱）(free gas drive)derives（获取）its energy from the pressure of the gas in the free gas cap.The expanding free gas cap sweeps（扫）the oil into the well.Gas cap drive is relatively efficient,producing 355 to 50%of the oil in place.第10页/共36页This type of reservoir is best developed with wells producing only from the oil portion of the reservoir,leaving the gas in the free gas cap to supply the energy.第11页/共36页 gravity（重力）is also a drive mechanism.It is present in all reservoirs,as the weight of the oil column creates pressure causing oil to flow into the well.This is usually insignificant（不太重要）compared to original pressures（原始压力）created by the other drive mechanisms.In the later stages（阶段）of oil production in a dissolved gas drive reservoir,however,gravity drainage（重力驱）becomes significant（重要）.This is called a gravity drainage pool（重力驱动油藏）.第12页/共36页（Hydrocarbon Recovery Ratio）（Total Produced Hydrocarbon）（Reserves in Place）100%=Recovery ratio（采收率）第13页/共36页Production of Oil and GasPrimary recovery（一次采收率）In primary recovery-the initial approach to produce oil-natural reservoir pressure（油藏的天然压力）or simple mechanical pumps（简单的机械泵）are used to raise oil to the surface.Until about 20 years ago recovery factors of over 20%during the primary production phase（一次生产阶段）were most exceptional（不常见的）.However modern techniques of field development and production have improved these figures considerably and now the average primary recovery（平均一次采收率）is between 20%and 30%.A number of methods can improve primary recovery.第14页/共36页The most common is infill drilling,which involves drilling more wells into the same pool so the oil does not have to travel as far through the rock to reach a wellbore.More than one directional well（定向井）can be drilled from a common platform（共同的钻井平台）.Horizontal drilling（水平钻井）,which extends（使延伸）the wellbore into a much large portion of the oil-bearing formation,has been employed since the late 1980s to improve production and enhance recovery.第15页/共36页Secondary recovery（二次采收率）:Further oil production can be obtained by injecting（注入）water(waterflooding)（水驱）or natural gas to maintain（保持）reservoir pressure and push（推）oil out of the rock,therefore achieve more efficient displacement（驱替）of oil.the development of secondary recovery schemes（方案）to be an almost standard practice in new fields has almost doubled（使翻倍）the overall recovery percentage.第16页/共36页Tertiary recovery（三次采收率）:The third major phase of crude oil recovery which uses more advanced（先进的）methods aiming to（旨在）increase oil recovery ratio.The most common tertiary recovery method for light and medium crude oil（轻质油和中质油）is miscible flooding（混相驱）.In this procedure,natural gas liquids(ethane,propane and butane)are injected into special injections wells（专门的注入井）.When dissolved,these liquids reduce（降低）surface tension（表面张力）and viscosity（粘稠度）to help release（释放）the oil from the reservoir rock.Carbon dioxide（二氧化碳）has also been used for miscible floods.This phase is applied before the well can be abandoned（废弃）.More Researches are conducted continuing to improve the recovery ratio.第17页/共36页Some factors that will limit producing rate.1.Low reservoir permeability（油藏渗透率低）2.Low reservoir pressure for depth（井深油藏压力低）3.Formation damage（地层破坏）4.Wellbore or tubing plugging（井筒或油管堵塞）5.High viscosity oil（高粘稠度油）6.Excessive back pressure on formation（地层回压过高）7.Inadequate artificial lift（人工举升不足）8.Other situation（其他情况）第18页/共36页Enhanced Oil Recovery（提高采收率）Enhanced oil recovery(EOR)processes have their objective（目标）to increase of oil recovery for reservoirs depleted（衰竭）by secondary recovery with water flooding or gas injection.The EOR processes can be divided into three categories;chemical（化学驱）,thermal（热力驱）and miscible（混相驱）,which can be further subdivided into various categories.Thermal processes have been used extensively for the displacement of heavy oil（重油驱替）,where as chemical and miscible displacement processes have been employed for the recovery of light oil（轻质油开采）.第19页/共36页Light oil:thinner,freely flowing crude oil of light specific gravity（特殊比重）.Heavy oil:dense,viscous oil,with a high proportion（比例）of bitumen,that is difficult to extract（开采）with conventional（传统的）techniques and is more costly to refine.第20页/共36页API degrees:the American Petroleum Institute（美国石油协会）defines the density（比重）of oil in gravity units called API degrees（API度）.The API degrees are expressed in the following formula（公式）:API degrees=141.5 -Special gravity 60/60 F-131.5Where specific gravity 60/60 F(15.5 C)is the gravity of the oil at 60 F compared with that of water at 60 F.Note that API degrees are inversely proportional（成反比）to density.Thus light oil have API gravities of over 40(0.83 specific gravity),whereas heavy oils have API gravities of less than 10(1.0 specific gravity).Heavy oils are thus defined as those oils that are denser than water.第21页/共36页Microbial enhanced oil recovery（微生物提高采收率法）The use of micro-organisms（微生物）and their metabolic products（代谢产物）to stimulate oil production is receiving interest worldwide.The technique involves the injection of selected（经过挑选的）micro-organisms into the reservoir.第22页/共36页EOR（提高采收率）Chemical flooding（化学驱）Thermal recovery（热力驱）Miscible flooding（混相驱）Surfactant flooding（表面活性剂驱）Polymer flooding（聚合物驱）Caustic flooding（碱法驱）In-situ combustion（火烧油层）Steam injection（蒸汽驱）Wet combustion（湿式燃烧）Miscible slug process（混相段塞法）Enriched gas process（富气注入法）High pressure lean gas process（高压贫气注入法）Mutual solvent process（中性溶剂注入法）CO2 process（二氧化碳注入法）第23页/共36页第24页/共36页Illustration of Steam Flood Process第25页/共36页There are three main types of conventional natural gas wells.Since oil is commonly associated with natural gas deposits（天然气藏）,a certain amount of natural gas may be obtained from wells that were drilled primarily for oil production.These are known as oil wells（油井）.In some cases,this“associated”natural gas is used to help in the production of oil,by providing pressure in the formation for the oils extraction（石油开采）.The associated natural gas may also exist in large enough quantities to allow its extraction along with the oil.Natural gas wells（天然气井）are wells drilled specifically for natural gas,and contain little or no oil.第26页/共36页Condensate wells（凝析油井）are wells that contain natural gas,as well as a liquid condensate（凝析油）.This condensate is a liquid hydrocarbon mixture that is often separated from the natural gas either at the wellhead,or during the processing of the natural gas.Depending on the type of well that is being drilled,completion may differ slightly.It is important to remember that natural gas,being lighter than air,will naturally rise to the surface of a well.Because of this,in many natural gas and condensate wells,lifting equipment and well treatment are not necessary.第27页/共36页Artificial Lift（人工举升）（人工举升）In most oilfields reservoir pressure decline（下降）and increased volumes（体积）of water produced with the oil give rise to（导致）conditions where the wells will not flow unaided（没有帮助）.A number of options,such as gas lift（气举）,subsurface pumps（潜泵）and rod pumps（有杆泵）,are open to assist oil flow to surface.第28页/共36页A Horse Head Pump for mechanic production well 第29页/共36页Key wordsseparation（分离）primary product（初级产品）the sponge（海绵状岩体）viscosity（粘稠度）clogging（堵塞）collapsing（跨塌）Interrupting production（间歇式的生产）exploit（开发）fracturing（压裂）cracks（裂隙）acids（酸）solvents（溶剂）acidizing（酸化）.第30页/共36页hydraulic fracturing（水力压裂）porous medium（孔隙介质）native stresses（天然压力）formation（地层）water drive（水驱）solution gas drive”(or“depletion drive”)（溶解气驱）gas cap drive”（气顶驱）gas bubbles（气泡）a gravity drainage pool（重力驱动油藏）recovery ratio（采收率）primary recovery（一次采收率）secondary recovery（二次采收率）waterflooding（水驱）第31页/共36页displacement（驱替）tertiary recovery（三次采收率）light crude oil（轻质油）medium crude oil（中质油）miscible flooding（混相驱）injections wells（注入井）surface tension（表面张力）Enhanced Oil Recovery（提高采收率）chemical（化学驱）thermal（热力驱）miscible（混相驱）the displacement of heavy oil（重油驱替）the recovery of light oil（轻质油开采）第32页/共36页specific gravity（特殊比重）microbial enhanced oil recovery（微生物提高采收率法）metabolic products（代谢产物）oil wells（油井）natural gas wells（天然气井）condensate wells（凝析油井）natural flow（自喷）artificial lift（人工举升）gas lift（气举）subsurface pumps（潜泵）rod pumps（有杆泵）第33页/共36页Questions for reviewing1.What does petroleum production refer to?2.What are the techniques,fracturing and acidizing,used to treat the formation in a reservoir?3.What are the main production mechanisms according to the natural sources of energy in a reservoir?4.Please write the equation of recovery ratio.5.What is Enhanced Oil Recovery?6.What are three categories that EOR processes can be divided into?7.How to define light oil and heavy oil?8.What is API degrees?第34页/共36页第35页/共36页