湘西北地区下寒武统牛蹄塘组页岩气成藏条件

利用野外露头、有机地球化学等资料,分析湘西北地区下寒武统牛蹄塘组页岩气资源勘探远景.初步研究表明,该地区下寒武统牛蹄塘组泥页岩有机质含量丰富、有机质类型好、热演化程度高,多数己达到成熟——过成熟阶段,是有效的页岩气烃源岩,可以作为今后页岩气勘探的目的层位.     

江西省瑞昌—德安下寒武统王音铺组页岩气勘探前景

为了解江西北部瑞昌—德安地区页岩气勘探前景,以下寒武统王音铺组炭质页岩为研究对象,对王音铺组页岩的古地理条件、埋深与厚度、有机地化指标以及页岩的矿物组成成分进行研究,结合页岩气保存条件的特殊性,初步认为研究区王音铺组炭质页岩具有较好的古地理环境、厚度大、埋深适中、生气能力大、脆性矿物含量高,页岩具有自生自储自保的特征,对页岩气的保存起到重要的作用,总体来说,研究区具有较好的页岩气勘探前景。     

页岩气开发现状及成功开发页岩气的关键因素

介绍页岩气的性质、特点、全球分布情况以及国内外勘探开发现状,世界范围内,泥、页岩约占全部沉积岩的60%,页岩气资源前景巨大。全球页岩气资源量为456.24×1012m3,主要分布在北美、中亚和中国、拉美、中东、北非以及前苏联地区等。我国页岩气可采资源量约为26×1012m3,与美国大致相当。在目前的经济技术条件下,页岩气是天然气工业化勘探的重要领域和目标。北美油气生产商把页岩气藏作为重要天然气开发目标,并且取得了巨大成功。通过对北美页岩气藏的深入研究并系统总结其勘探开发历史与成功经验,认为其有效勘探开发的关键在于有政策引导和水平井、水力压裂等先进钻、完井技术的成功应用。我国页岩气资源潜力很大,但我国对页岩气的研究与勘探开发尚处于探索阶段。从勘探技术、钻井技术、开发技术和政策支持四方面论述了页岩气开发的难点和技术对策,提出了国内页岩气成功开发的工作思路,对国内开展相关技术的研究有一定的指导意义。     

中上扬子地区五峰-龙马溪组页岩气开发评价关键问题

北美页岩气田以海相沉积储层、热成因气为主,其页岩气的有效开发改变了全球天然气供给格局。通过十余年的勘探开发攻关,我国页岩气资源也实现了有效开发,2016年产量达到78×10~8m~3,中上扬子地区五峰-龙马溪组底部富有机质页岩是当前我国页岩气开发的主力层系。与北美相比,中上扬子地区构造条件相对复杂,页岩气储层具特殊性,在有效开发探索实践过程中仍存在多项难题亟待解决:静态储量和动态储量的匹配问题、地质和工程因素对气井产量影响的问题、现有技术对全区域页岩气开发有效性的问题、浅层常压储层页岩气开发潜力的问题以及页岩气井网加密可行性问题。针对页岩气开发评价存在的问题,提出了通过页岩储集机理研究准确评价页岩气储量,落实影响页岩气开发效果的地质和工程因素,通过地质-开发-经济一体化评价落实资源的开发有效性,加强成本管控实现浅层常压页岩气资源有效开发,开展井网加密现场试验储备页岩气田稳产接替技术等建议。     

宁武盆地山西—太原组煤系页岩气储层勘探潜力探讨

由于页岩气资源更丰富、开采周期长、产量高,已经成为一种至关重要作用的非常规天然气资源。近期,为了加快中深层煤系页岩气资源落实,在宁武盆地以煤层气和致密气两种类型勘探领域分别部署的NT8X井和NT4X井,在山西—太原组地层中泥页岩、致密砂岩、煤层段均钻遇良好的气测显示,泥页岩累计厚度175～190m,TOC在2.6%～5.2%,含气丰度高,气测全烃大于30%的泥页岩面积150km2,区内断层发育较少,有利于煤系页岩气保存及成藏。由于该区煤系页岩气属于勘探新领域,目前尚未取得重大突破。立足于山西—太原组煤系页岩气储层,通过整理分析已钻井资料,从生烃条件、储层特征、保存条件三个方面,开展煤系页岩气储层的综合评价。根据评价结果结合平面展布情况初步优选盆地北部宁武洼槽带为有利区带,具有较大的资源潜力,为宁武盆地下步勘探开发提供了一定依据。     

闽西南溪口组页岩储层有机地球化学特征及含气潜力

分析有机地球化学特征对于页岩气资源的勘探开发有重大意义。为此,以闽西南下三叠统溪口组页岩储层为研究对象,对该层位页岩样品进行有机地球化学特征分析。分析结果表明闽西南溪口组页岩储层有低有机质、高演化的特征,有机质类型为Ⅲ型。分析认为,溪口组页岩储层生烃物质基础较差,生气潜力不理想。     

重庆页岩气产业收益率分析及建议

虽然重庆市境内天然气资源丰富,是我国第一个页岩气规模化生产地区,但由于页岩气勘探开发项目产量不确定性高、单井投资大、补贴前景不明朗等客观条件,并伴随着页岩气勘探开发风险大,收益率不稳定等负面影响,在一定程度上抑制了石油企业对页岩气产业的投资规模,从而约束了页岩气田的勘探开发程度.为扎实推进页岩气勘探开发,进一步保障重庆...     

不同成因类型页岩气藏特征分析

页岩气具有储层致密低渗,自生自储式成藏的特点,美国页岩气的成功开发是油气领域的新突破。2011年,美国页岩气产量超过1700×108m3,天然气基本实现自给,在一定程度上改变了世界天然气的供应格局。按照天然气的成因类型,页岩气可划分为热成因和生物成因两类。重点分析Barnett热成因页岩气藏和Antrim生物成因页岩气藏的地质特征和开发特征。我国已完钻页岩气井51口,其中直井37口,水平井14口;直井压裂试气15口,水平井压裂试气4口,14口见气;南方海相页岩气、四川盆地和鄂尔多斯盆地陆相页岩气勘探取得突破。通过我国南方海相热成因页岩气地质特征的对比分析,认为我国页岩气藏具有特殊性,储层条件更为复杂,美国页岩气开发技术不能完全适应我国页岩气的开发需求。另外,我国松辽和鄂尔多斯等盆地广泛发育富有机质页岩,但成熟度普遍偏低,热成因页岩气前景有限,但生物成因页岩气具有良好的成藏条件,是页岩气勘探的重点方向。     

世界页岩气资源现状研究

页岩气的勘探开发引起国际社会的高度关注,其资源分布与资源潜力成为研究的热点。页岩气资源主要分布于北美、中亚、中国、中东、北非和非洲南部等国家和地区。据EIA最新的评价结果,全球页岩油和页岩气技术可采资源量分别为473×108t和207×1012m3,分别占油气资源总量的10%和32%。中国页岩气和页岩油技术可采资源量分别为31.6×1012m3和44.1×108t,分别居世界首位和第三位。世界页岩气技术可采资源量排名第二位、第三位的国家分别是阿根廷和阿尔及利亚,资源量分别为22.71×1012m3和20.02×1012m3。俄罗斯拥有102.19×108t页岩油技术可采资源量,居世界首位,阿根廷、利比亚、委内瑞拉和墨西哥等国也拥有丰富的页岩油资源。非常规油气已成为全球油气供应的重要组成部分,非常规油气产量占油气总产量的比例已超过10%。非常规油气勘探开发技术取得的成果包括连续型油气聚集理论、水平井规模压裂技术、平台式"工厂化"开发模式。将多学科的先进技术综合应用到勘探领域,是目前页岩油气勘探技术的发展方向。以美国为首的西方发达国家将继续引领全球页岩气勘探开发技术的潮流。     

湘西北下寒武统牛蹄塘组石煤研究综述

石煤是早古生代浅海环境中主要由菌藻类、海绵等原始动、植物遗体在浅海环境条件下经过成千上万年的腐泥化作用和煤化作用而形成的高硫分、高灰分、低热值的劣质煤。中国湘西北下寒武统石煤的蕴藏量大,并且其伴生矿含量也丰富。加强石煤及其伴生矿产的研究,对其综合勘探、综合开发和综合利用等方面意义重大。对湘西北下寒武统牛蹄塘组石煤特征、成因及其伴生的矿产资源进行了综述,最后分析了前人研究中存在的问题,并进一步对研究方向进行了展望。     

Ash-forming elements in four Scandinavian wood species. Part 1: Summer harvest

Woody biomass in Finland and Sweden comprises mainly four wood species: spruce, pine, birch and aspen. To study the ash, which may cause problems for the combustion device, one tree of each species were cut down and prepared for comparisons with fuel samples. Well-defined samples of wood, bark and foliage were analyzed on 11 ash-forming elements: Si, Al, Fe, Ca, Mg, Mn, Na, K, P, S and Cl. The ash content in the wood tissues (0.2–0.7%) was low compared to the ash content in the bark tissues (1.9–6.4%) and the foliage (2.4–7.7%). The woods’ content of ash-forming elements was consequently low; the highest contents were of Ca (410–1340 ppm) and K (200–1310), followed by Mg (70–290), Mn (15–240) and P (0–350). Present in the wood was also Si (50–190), S (50–200) and Cl (30–110). The bark tissues showed much higher element contents; Ca (4800–19,100 ppm) and K (1600–6400) were the dominating elements, followed by Mg (210–2400), P (210–1200), Mn (110–1100) and S (310–750), but the Cl contents (40–330) were only moderately higher in the bark than in the wood. The young foliage (shoots and deciduous leaves) had the highest K (7100–25,000 ppm), P (1600–5300) and S (1100–2600) contents of all tissues, while the shoots of spruce had the highest Cl contents (820–1360) and its needles the highest Si content (5000–11,300). This paper presented a new approach in fuel characterization: the method excludes the presence of impurities, and focus on different categories of plant tissues. This made it possible to discuss the contents of ash element in a wide spectrum of fuel-types, which are of large importance for the energy production in Finland and Sweden.     

NEXT GENERATION ENGINEERED MATERIALS FOR ULTRA SUPERCRITICAL STEAM TURBINES

正1 ABSTRACT To reduce the effect of global warming on our climate,the levels of CO2emissions should be reduced.One way to do this is to increase the efficiency of electricity production from fossil fuels.This will in turn reduce the amount of CO2emissions for a given power output.Using US practice for efficiency calculations,then a move from a typical US plant running at 37%efficiency to a 760℃/38.5 MPa(1 400/5 580 psi)plant running at 48%efficiency would reduce CO2emissions by 170kg/MW.hr or 25%.     

Contents in Volume 23,2014

<正>~~     

Aerodynamic performance effects of leading-edge geometry in gas-turbine blades

The purpose of this paper is to illustrate the advantages of the direct surface-curvature distribution blade-design method, originally proposed by Korakianitis, for the leading-edge design of turbine blades, and by extension for other types of airfoil shapes. The leading edge shape is critical in the blade design process, and it is quite difficult to completely control with inverse, semi-inverse or other direct-design methods. The blade-design method is briefly reviewed, and then the effort is concentrated on smoothly blending the leading edge shape (circle or ellipse, etc.) with the main part of the blade surface, in a manner that avoids leading-edge flow-disturbance and flow-separation regions. Specifically in the leading edge region we return to the second-order (parabolic) construction line coupled with a revised smoothing equation between the leading-edge shape and the main part of the blade. The Hodson–Dominy blade has been used as an example to show the ability of this blade-design method to remove leading-edge separation bubbles in gas turbine blades and other airfoil shapes that have very sharp changes in curvature near the leading edge. An additional gas turbine blade example has been used to illustrate the ability of this method to design leading edge shapes that avoid leading-edge separation bubbles at off-design conditions. This gas turbine blade example has inlet flow angle 0°, outlet flow angle −64.3°, and tangential lift coefficient 1.045, in a region of parameters where the leading edge shape is critical for the overall blade performance. Computed results at incidences of −10°,   −5°,   +5°,   +10° are used to illustrate the complete removal of leading edge flow-disturbance regions, thus minimizing the possibility of leading-edge separation bubbles, while concurrently minimizing the stagnation pressure drop from inlet to outlet. These results using two difficult example cases of leading edge geometries illustrate the superiority and utility of this blade-design method when compared with other direct or inverse blade-design methods.     

Hydrogen production by steam-gasification of carbonaceous materials using concentrated solar energy – V. Reactor modeling,optimization, and scale-up

A chemical reactor for the steam-gasification of carbonaceous particles (e.g. coal, coke) is considered for using concentrated solar radiation as the energy source of high-temperature process heat. A two-phase reactor model that couples radiative, convective, and conductive heat transfer to the chemical kinetics is applied to optimize the reactor geometrical configuration and operational parameters (feedstock's initial particle size, feeding rates, and solar power input) for maximum reaction extent and solar-to-chemical energy conversion efficiency of a 5 kW prototype reactor and its scale-up to 300 kW. For the 300 kW reactor, complete reaction extent is predicted for an initial feedstock particle size up to 35 μm at residence times of less than 10 s and peak temperatures of 1818 K, yielding high-quality syngas with a calorific content that has been solar-upgraded by 19% over that of the petcoke gasified.     

汽轮机数字电液调节系统挂闸异常的技术完善

分析了200MW汽轮机数字电液调节系统在运行中存在的挂闸异常问题,采取了相应的技术处理措施,且运行实践效果良好。     

新型高压共轨ECU升压模块的数字化开发与优化

为了提高喷油器电磁阀的响应速率,提出了一种基于CPLD(复杂可编程逻辑器件)应用于高压共轨ECU的数字升压模块。鉴于该升压电路结构参数多,其升压电压的恢复响应要求高等特征,基于Pspice建立了升压电路的仿真模型,研究了不同电路参数下升压模块的输出特性,全面优化了该升压模块的性能。结果显示,该升压模块的最大转换效率可以达90%以上。在柴油发动机上对ECU的试验表明,升压电压最大波动不超过10%,其恢复时间仅为1.3ms,功率管最大温升仅为41℃,满足整机运行范围内ECU的需求。     

Trace metal chemistry and silicification of microorganisms in geothermal sinter, Taupo Volcanic Zone, New Zealand

As part of a pilot study investigating the role of microorganisms in the immobilisation of As, Sb, B, Tl and Hg, the inorganic geochemistry of seven different active sinter deposits and their contact fluids were characterised. A comprehensive series of sequential extractions for a suite of trace elements was carried out on siliceous sinter and a mixed silica-carbonate sinter. The extractions showed whether metals were loosely exchangeable or bound to carbonate, oxide, organic or crystalline fractions. Hyperthermophilic microbial communities associated with sinters deposited from high temperature (92–94°C) fluids at a variety of geothermal sources were investigated using SEM. The rapidity and style of silicification of the hyperthermophiles can be correlated with the dissolved silica content of the fluid. Although high concentrations of Hg and Tl were found associated with the organic fraction of the sinters, there was no evidence to suggest that any of the heavy metals were associated preferentially with the hyperthermophiles at the high temperature (92–94°C) ends of the terrestrial thermal spring ecosystems studied.     

Assessment methods of material ageing using Sdobyrev''s creep rupture model

The physical aspects of the activation energy, in higher and high temperatures, of the metal creep process were examined. The research results of creep-rupture in a uniaxial stress state and the criterion of creep-rupture in biaxial stress states, at two temperatures, are then presented. For these studies creep-rupture, taking case iron as an example the energy and pseudoenergy activation was determined. For complex stress states the criterion of creep-rupture was taken to be Sdobyrev's, i.e. σ_red = σ₁ β + (1 − β)σ_i, where: σ₁-maximal principal stress, σ_i-stress intensity, β-material constant (at variable temperature β = β(T)). The methods of assessment of the material ageing grade are given in percentages of ageing of new material in the following mechanical properties: 1) creep strength in uniaxial stress state, 2) activation energy in uniaxial stress state, 3) criterion creep strength in complex stress states, 4) activation pseudoenergy in complex stress states. The methods 1) and 3) are the relatively simplest because they result from experimental investigations only at nominal temperature of the structure work, however, for methods 2) and 4) it is necessary to perform the experimental investigations at least at two temperatures.     

Production of hydrogen from sewage biosolids in a continuously fed bioreactor: Effect of hydraulic retention time and sparging

Hydrogen was produced from primary sewage biosolids via mesophilic anaerobic fermentation in a continuously fed bioreactor. Prior to fermentation the sewage biosolids were heated to 70 °C for 1 h to inactivate methanogens and during fermentation a cellulose degrading enzyme was added to improve substrate availability. Hydraulic retention times (HRT) of 18, 24, 36 and 48 h were evaluated for the duration of hydrogen production. Without sparging a hydraulic retention time of 24 h resulted in the longest period of hydrogen production (3 days), during which a hydrogen yield of 21.9 L H₂ kg⁻¹ VS added to the bioreactor was achieved. Methods of preventing the decline of hydrogen production during continuous fermentation were evaluated. Of the techniques evaluated using nitrogen gas to sparge the bioreactor contents proved to be more effective than flushing just the headspace of the bioreactor. Sparging at 0.06 L L min⁻¹ successfully prevented a decline in hydrogen production and resulted in a yield of 27.0  L H₂ kg⁻¹ VS added, over a period of greater than 12 days or 12 HRT. The use of sparging also delayed the build up of acetic acid in the bioreactor, suggesting that it serves to inhibit homoacetogenesis and thus maintain hydrogen production.