松辽盆地南部腰英台地区白垩系登娄库-泉头组储层成岩作用

松辽盆地南部腰英台地区白垩系登娄库-泉头组储集层岩石类型以长石岩屑质石英砂岩、长石质岩屑砂岩和岩屑砂岩为主,岩石结构成熟度和成分成熟度均不高。储层成岩作用主要有压实作用、胶结作用、压溶和溶蚀作用、交代作用以及次生加大作用等。研究区储集层成岩演化处于晚成岩A期和B期。其中压实作用和胶结作用使储层原生孔隙迅速减少、渗透率降低,是导致研究区储层物性变差的主要原因,溶蚀作用则是次生孔隙发育的主要因素,从而在一定程度上改善研究区砂岩的储层物性。     

榆林气田长北区块山1段储层特征研究

榆林气田上古生界储层发育广泛,其上古生界地层为石炭系-二叠系,石炭系包括本溪组和太原组,为一套海相沉积。山西组为一套煤系地层,属于三角洲平原沉积。通过岩心薄片、铸体薄片、压汞测定、扫描电镜等实验方法,对榆林气田长北区块山1段的砂体展布特征、储层特征以及成岩作用等进行了研究。研究表明:榆林气田长北区块山1段属于低孔低渗储层;岩性以岩屑石英砂岩和岩屑砂岩为主;长北区块主要发育原生粒间孔隙、次生溶孔、高岭石晶间微孔隙和微裂隙四类孔隙;成岩作用对储层物性有着重要的意义。榆林气田长北区块山1段的储层特征的研究,为进一步开发榆林气田长北区块提供了科学依据。     

松北登娄库组储层特征分析

通过多种测试分析手段对不同岩石样品的岩性、物性、酸性、孔隙结构与类型,认为物性是评价登娄库组储层好坏的重要因素,而次生孔隙的发育程度又决定储层物性的好坏,因此地层水中的酸溶蚀产生的次生孔隙是判断有利储层的主要依据。通过孔隙度、渗透率、脂肪酸、酚、浊沸石、碳酸盐等与地层埋深关系的分析,认为有利储层与次生孔隙发育带联系紧密,通过次生孔隙的发育带可判断有利储层发育深度。     

大邑构造须家河组二段致密砂岩成岩作用对储层物性的影响

本文在综合分析大量岩石薄片、扫描电镜、阴极发光、X-射线衍射以及大量测试分析等资料的基础上,详细研究了各种成岩作用对储层物性的影响,建立了该区致密砂岩储层的成岩演化序列及孔隙演化模式。研究认为,大邑构造须二段砂岩主要处于中成岩B期;成岩作用是优质储层发育最直接也是最重要的控制因素之一,其中压实作用、胶结作用是造成该区储层物性降低的主要因素,溶蚀作用形成的次生孔隙使储层物性得到改善,有效微裂缝的发育是优质储层形成的关键因素。     

滩海东部沙河街组储层特征及影响因素分析

以近几年所钻揭露沙河街组探井为出发点,通过综合分析沙河街组砂岩的岩石类型及碎屑成分、成岩作用及演化、物性特征及成岩作用对物性影响因素,对沙河街组砂岩储层进行深入研究。结果表明,滩海东部沙河街组岩石类型为长石岩屑砂岩和岩屑长石砂岩,主要成岩作用类型为压实作用、胶结作用和溶蚀作用等,沙河街组深部沙三段已经进入晚成岩B期;沙一段为中低孔—低-特低渗储层,沙三段为低孔—特低-超低渗储层。溶蚀作用是深部次生孔隙发育的主要成岩作用。     

四川盆地洛带气田蓬莱镇组气藏储层特征研究

洛带气田蓬莱镇组属于浅水三角洲沉积,储层主要储集空间以粒间孔为主,其次是粒内溶孔、晶间孔,岩石中裂缝、微裂缝极少发育,属孔隙型储层。储层主要储集空间以粒间孔为主,其次是粒内溶孔、晶间孔,岩石中裂缝、微裂缝极少发育,属孔隙型储层。储层受压实、胶结作用的影响较大,使得其储层物性有所变差。孔隙度在10%～13%的储层与孔隙度大于13%的储层比例相当,其次为孔隙度在6%～10%之间的储层。溶蚀作用是该区储层最重要的成岩作用之一,溶蚀作用产生的次生孔隙可以极大改善储层因受到压实、方解石的胶结作用等导致的孔隙性破坏,研究区内常常可以见到次生孔隙特别发育等多期溶蚀的证据。从储层的成岩及后生改造作用可以看出,以胶结作用为主的成岩后生作用影响最为显著,只有溶解作用和交代作用对孔喉有一定的改善作用。     

HH气田花港组储层特征及主控因素分析

通过薄片鉴定及样品测试等研究工作,对该气田花港组低孔渗砂岩储层的储层物性、储集空间类型、孔隙结构以及影响储层发育的主控因素进行了分析。认为研究区花港组储层属低孔低渗储层,储层主要受沉积微相、成岩作用、烃类充注等因素的影响。     

升平地区登娄库组储层沉积特征

不同沉积体系所形成的储层具有不同的展布规律和非均质特征,沉积岩储层的沉积特征是决定油气储层的综合特性之一。目前升平地区区块1登娄库组储层提交了一定天然气探明地质储量,其周边散布的探井分布面积广,具有一定开发潜力。文章在地质与测井资料相结合基础上,运用现代沉积学理论和方法,对其分布地区登娄库组地层进行沉积特征分析,确定该区主要发育河流、三角洲、湖泊沉积相,阐明了该区登娄库组沉积相的纵向组合及平面分布特征,同时揭示了有利储层时空分布,指导气田下步开发。     

四川盆地中西部地区须家河组砂岩储层微观孔隙特征与成岩作用

四川盆地上三叠统须家河组是重要的天然气勘探领域,其砂体分布广泛而稳定,但储层非均质性强。为了揭示不同区域须家河组储层特征的差异,通过镜下铸体薄片观察,结合扫描电镜、X衍射分析等技术手段,对区内须家河组储层微观孔隙特征与成岩作用进行研究。研究结果表明,须家河组储层岩石类型以长石岩屑砂岩和岩屑长石砂岩为主,孔隙类型由原生粒间孔、粒间溶孔、粒内溶孔、铸模孔和裂缝构成,其中粒间溶孔和粒内溶孔是最主要的孔隙类型,且各区域各层段岩石学特征及微观孔隙特征表现出明显的差异性;成岩作用包括破坏性成岩作用和建设性成岩作用,其中破坏性成岩作用主要为压实作用和胶结作用,建设性成岩作用为溶蚀作用和破裂作用,前者导致中西部地区须家河组储层逐渐演变为致密砂岩储层,后者作用占主导则导致致密砂岩储层中发育与保存相对优质储层。     

鄂尔多斯盆地西南部延长组储层砂岩主要成岩作用

鄂尔多斯盆地西南部延长组储层主要由岩屑长石砂岩、长石岩屑砂岩和长石砂岩组成,富岩屑长石、相对贫石英、结构成熟度成份成熟度低是其骨架颗粒的主要特征。自生矿物主要有方解石、绿泥石、石英、高岭石等。储层经历了压实作用、胶结作用和溶解作用等成岩作用的改造,目前处于中成岩B期。受早期绿泥石膜保护而保存下来的原生孔隙和溶解作用形成的次生孔隙是研究区主要储集空间,绿泥石包膜的形成和溶解作用的发育在研究区孔隙保护和演化中起到了重要作用。     

焦炭气孔率对焦炭热性能的影响

通过研究40kg试验焦炉单种煤焦炭、配合煤焦炭及工业焦炉焦炭的气孔结构及焦炭热性能,得出气孔率对焦炭热性能的影响。焦炭气孔率对焦炭热性能有较大影响,随着气孔率的增加,CRI增加,CSR降低;工业焦炉焦炭气孔率与焦炭热强度之间关系密切,气孔率每增加1％,CRI增加0．48％,CSR降低1．46％。用气孔率预测焦炭热性能,对指导焦炭生产、控制焦炭热性能具有指导意义。     

煤的孔隙结构与反应性关系的研究进展

煤在气化、燃烧与活性炭制备等热化学转化过程中，均存在着孔隙结构与表面积的变化．煤的孔隙结构变化特征的研究是煤炭高效合理利用的基础．从煤的孔隙结构的表征、反应过程中孔隙结构变化以及孔隙结构模型三方面总结了煤的孔隙结构与反应性关系领域的研究现状，并对今后的研究重点进行了展望，即加强孔隙结构与反应性关系通用规律和催化剂对孔隙结构影响两方面的研究．     

Hardened alite pastes of various porosities II. Morphology and microstructure

The hardened alite pastes were prepared by using initial water:alite ratios of 0.20, 0.30, 0.45 and 0.60. The microstructures of the low and high porosity pastes were investigated by scanning electron microscopy. The results obtained indicated that the cementing system is really a composite material having a structure controlled by the total pore system of the hardened paste. In low porosity pastes, the hydration products are semi-crystalline; whereas in high porosity pastes, the hydration products possess a massive tabular structure.     

Analyses of Young's modulus and thermal expansion coefficient of sintered porous alumina compacts

This paper reports the derivation of Young's modulus (E) and thermal expansion coefficient (TEC, β) for a sintered porous structure with open pores. The theoretical E is affected by the number of grains and the grain boundary area in sintered ceramics. The measured E–porosity relationship for porous alumina compacts were compared with the theoretical E values that were derived for the present open-pore structure and also for the dispersed (closed)-pore structure treated previously. With decreasing porosity (50% → 10%), the scattered E values showed a gradually increasing tendency, which were located between two theoretical curves for the open-pore structure. The sudden increase of E values in the porosity range from 10% to 0% was well explained by the theoretical dependence of E on porosity for the open- or closed-pore structure. The β values for the porous alumina structures were independent of porosity and close to the β values reported for fully dense alumina compacts. This result was in accordance with the theoretical β–porosity relationships for the open-pore and closed-pore structures.     

Theoretical and experimental analyses of thermal properties of porous polycrystalline mullite

This paper examined experimentally and theoretically the thermal diffusibility (α), heat capacity (C_P1) at a constant pressure (1 atm, 101.33 kPa) and thermal conductivity (κ=C_P1α) for the porous mullite ceramics with 0–55% porosity in a wide temperature range from 298 to 1073 K. The change in the κ values with temperature or porosity for the porous mullite was similar to the temperature dependence or porosity dependence of the α values, which were greatly reduced by the air included in the pores. The κ values for the porous mullite were theoretically analyzed with two model structures of pore–dispersed mullite continuous phase system (A model) and mullite–dispersed pore continuous phase system (B model). The measured κ values at 0–23% porosity agreed well with the κ values calculated for model A structure. In the high porosity range from 33% to 55%, the measured κ values deviated from the κ curve calculated for model A structure and approached the κ value curve for model B structure with increasing porosity. The real microstructure of 30–60% porosity is equivalent to the mixed microstructure of model A and model B for the thermal conductivity measurement.     

Investigation of O/W emulsion separation and redispersion using fibrous PTFE bed coalescer

A series of fiber beds consisted of woven PTFE fiber mesh were used to investigate the influence of bed porosity (gradient porosity), permeability, specific surface area of bed, and superficial velocity on coalescence and separation process. It is found that too small bed porosity will not give better separation performance, for the reason of redispersion. The separation efficiency does not depend on the pore size but on the surface area of bed when the porosity is above 0.850. And a rapid drop of separation efficiency takes place above the porosity of 0.903. For effective separation of liquid droplets from a fluid stream, the gradient increasing porosity is the most favorable structure, which is effective to avoid redispersion of coalesced droplets.     

Investigation of coals and blends deposit structure: measuring the deposit bulk porosity using thermomechanical analysis technique

This study investigated the deposit structure in terms of the bulk porosity for Australian bituminous coals and blends that were fired in a pilot-scale test furnace. The first part of this study estimated all the deposits bulk porosity using two indirect techniques: a density measurement technique and by scanning electron microscopy (SEM). The results showed a significant difference between the two techniques. The density measurement underestimated the bulk porosity of the deposit due to the closed pores within the deposit structure. The second part of this study proposed a novel experimental approach to measure the changes in the deposit bulk porosity at elevated temperatures using thermomechanical analysis technique (TMA). The TMA bulk porosity measurements were comparable with the SEM results.     

Modeling of diffusive mass transport in micropores in cement based materials

In order to predict long-term leaching behavior of cement constituents for safety assessments of radioactive waste disposal, we modeled diffusive mass transport in micropores in cement based materials. Based on available knowledge on the pore structure, we developed a transport porosity model that enables us to estimate effective porosity available for diffusion (transport porosity) in cement based materials. We microscopically examined the pore structure of hardened cement pastes to partially verify the model. Effective diffusivities of tritiated water in hardened cement pastes were also obtained experimentally, and were shown to be proportional to the estimated transport porosity.     

Analysis of particle porosity distribution in fixed beds using the discrete element method

This report discusses the use of the discrete element method (DEM) to the porosity distribution of spherical particles in narrow pipes as a function of the pipe-to-particle diameter ratio. It was found that the packing structure depends mainly on the pipe-to-particle ratio and the particle friction. The numerical results with respect to the radial porosity distribution are in agreement with experimental data from the literature. Radial porosity distributions were calculated using algorithms developed by Mueller. The packing structure of the particles shows channeling for small pipe to particle diameter ratios. The simulated height averaged porosity distribution agrees with models from the literature. Moreover, DEM provides the possibility to include particle properties which reflect on the porosity distribution.     

Modeling of pore structure evolution within the fiber bundle during chemical vapor infiltration process

Taking into account the gas diffusion parallel and perpendicular to the bundle axis, a two-dimensional model combining the non-conservative level set method and the steady-state diffusion equation is presented for evolving pore structure in the bundle cross-section. Parametric studies have been conducted to determine the sensitivity of residual porosity within the bundle to the structure parameters. Sheldon and Besmann's approach is revised and more realistic approximated expressions depicting the accessible and total porosity evolution inside the bundle are given. Such expression can serve as useful estimate of pore structure evolution for modeling the CVI process.