页岩气侧钻水平井油基泥饼固化剂性能评价与现场试验

为进一步解决页岩气侧钻水平井环空带压难题,介绍了一种适用于油基钻井液条件下的油基泥饼固化剂GOS。性能评价结果表明:1) 养护条件为105℃ ×常压和油基泥饼厚度为0.3 mm时,随着养护时间的延长,采用油基泥饼固化剂的页岩气侧钻水平井固井二界面胶结强度增大且达到了0.1002~0.3974 MPa,而未采用油基泥饼固化剂的页岩气侧钻水平井固井二界面胶结强度则基本为0.0042~0.0082 MPa,即前者较后者的固井二界面胶结强度提高了19.44~53.43倍;2) GOS与油基钻井液和水泥浆具有良好的相容性,满足页岩气侧钻水平井固井作业要求。4口页岩气侧钻水平井的现场试验结果表明,固井质量合格率100%,固井一界面胶结质量优良率90%以上,固井二界面胶结中等以上的超过80%。其中,T1侧钻水平井目前已完成体积压裂测试,页岩气产量7.5013万方/日,页岩油产量9.87方/日,且油层套管与表层套管之间环空压裂前后均未出现带压,为页岩油气的高效勘探开发提供了良好的井筒保障。

泥页岩基质渗透率样品制备方法探究

泥页岩储层渗透率是油气藏开发过程中最重要同时也是最难获得的储层物性参数之一,目前比较好的测量泥页岩渗透率的方法为岩屑压力衰减法,该方法所需颗粒样品直径的最优区间为500~850μm,最优样品质量为25~30g。但是目前样品处理方法主要是手工碎样,该方法耗时耗力,工作效率低,而且需要样品量较大,对于寸土寸金的岩芯样品来说,是极大的浪费,因此建立新的样品处理方法是十分必要的。为明确和建立泥页岩基质渗透率实验最佳的样品处理方法,采用德国莱驰(Retsh)公司的BB51型颚式粉碎仪,将块状岩石样品粉碎为颗粒样品,再用合适粒径的样品筛对样品进行筛分,最终确定出所需样品的最佳实验条件。对50余块样品进行粉碎测试,通过改变碎样间距、碎样次数等条件来确定不同条件下不同粒径样品的产出比例及变化规律,最终确定了泥页岩基质渗透率所需样品的最佳粉碎间距为1.0mm左右。其中单次样品出样比例为19.8%,三次累计出样比例为30.6%,所需样品最少质量为82g。通过泥页岩基质渗透率样品处理方法研究,极大地提高了样品处理的工作效率,降低了人工成本,减少了样品使用量。

羊粪蘑菇泥基质对葡萄生长及果实品质的影响

以阳光玫瑰葡萄为试验材料,采用槽沟+起垄式栽培,通过原土栽培(对照)、槽沟下半层羊粪基质+上半层蘑菇泥基质+原土起垄的半基质栽培、槽沟羊粪基质+蘑菇泥基质起垄的全基质栽培3个处理,开展羊粪、蘑菇泥基质栽培试验。结果表明,全基质、半基质栽培对植株生长的促进作用显著,茎秆直径比对照增粗4.22~5.75 mm;当年生枝梢节间增长2.44~4.61 cm、增粗0.67~0.84 mm,叶片增厚0.07~0.09 mm。全基质、半基质栽培明显提高了葡萄的单果重和品质,可溶性固形物含量提升至18.53%~19.12%,固酸比升至32.51~32.97;但穗重、果形指数、可滴定酸含量与对照差异不显著。

铌基波纹膜片材料抗蚀性研究

用称重法、电化学方法以及做成元件实用考核等办法，研究了锐基波纹膜片材料（Ｎｂ－１～５Ｍｏ－１～３Ｚｒ－≤４Ｔｉ）抗蚀性能。试验结果如下：在１００～１２６℃浓醋酸、次氯酸钠、海水以及干在湿氧气中，没泡１～２年后，该合金试片表面仍光亮，未发现任何腐蚀斑点。根据试验前后重量变化，计算出的腐蚀速率很低（１０￣（－４）～１０￣（－５）ｍｍ／年）。该合金波纹膜片装入差压变送器中，在上述介质中使用２年后，波纹膜片仍光亮，未出现任何受腐蚀的痕迹，而且，变送尽的精度始终保持优于０．５好。电化学实验证明：该合金在含Ｃ￣（－）离子介质中具有很高的钝性，钝态区宽度≥２Ｖ，产生点蚀的临界电位＞１．７Ｖ；该合金自然浸泡在含Ｃｌ￣（－）离子介质中可自发地形成钝化膜，而且当钝化膜被磨损后能迅速自行修复。

油基钻井液条件下页岩气侧钻水平井固井技术

DYS4侧钻水平井完钻井深5587 m,垂深4186.34 m,水平位移1607.72 m,具有油基钻井液固相含量高、井壁和套管壁清洗困难、封固段长(5584.49 m)、顶底部温差大(110℃)、顶替效率难以保证等诸多固井难点。通过优化固井方案,优选了双凝双密度水泥浆体系和驱油型隔离液体系,且采用了油基泥饼固化剂,制定了配套防气窜、井眼清洁等固井技术措施。现场应用结果表明,该井固井一、二界面胶结质量优质,有效封固了页岩气水平段,达到了预期目的,为后续大型分段体积压裂奠定了良好的井筒基础,同时也可为油基钻井液条件下的水平井固井提供借鉴和参考。

英南2井气藏致密砂岩盖层的形成

钻井取心和录井资料显示,塔里木盆地英南2井侏罗系气藏中的主力气层之上均为砂岩,缺少泥岩盖层.通过对铸体薄片的观察,结合电性、物性、压汞、扫描电镜和黏土矿物X衍射分析资料,发现英南2井主力气层之上有两段致密砂岩层能够作为气藏的有效盖层.致密砂岩层内富含高度分散的泥杂基(含量达6.6%～13.8%),呈网状和包膜状分布于砂粒表面和粒间,其强烈的水锁效应能使气体渗透率降低80%以上,在含水条件下,气体渗透率可由0.47～0.69mD降至小于0.1mD或趋于不渗透状态,这是这类致密砂岩成为有效盖层的主要原因.

Experimental and numerical study on flexural behaviors of steel reinforced engineered cementitious composite beams

To investigate the flexural behaviors of steel reinforced engineered cementitious composite （ECC） beams, the behaviors of the steel reinforced ECC beam and the conventional steel reinforced concrete beam subjected to flexural load are experimentally compared. The experimental results show that the flexural strength and ductility of the steel reinforced ECC beam are 24.8% and 187.67% times larger than those of the steel reinforced concrete beam, and the substitution of concrete with ECC can significantly delay the propagation of cracks. Additionally, a simplified constitutive model of the ECC material is used to simulate the flexural behaviors of beams by the finite element analysis （FEA）. The results show a good agreement between the simulation and test results. The crack width of the steel reinforced ECC beam can be limited to 0.4 mm under the service load conditions. The application of ductile ECC can significantly increase the flexural performance in terms of flexural strength, deformation capacity and ductility of the beams.

Enhanced photocatalytic performance of cementitious material with TiO_2@Ag modified fly ash micro-aggregates

A TiO2 photocatalyst is coated on the surface of a zeolite fly ash bead（ZFAB） to improve its dispersability and exposure degree in a cement system.The application of Ag particles in TiO2/ZFAB modified cementitious materials is to further enhance the photocatalytic performance.Various Ag@TiO2/ZFAB modified cementitious specimens with different Ag dosages are prepared and the characteristics and photocatalytic performance of the prepared samples are investigated.It is observed that the multi-level pore structure of ZFAB can improve the exposure degree of TiO2 in a cement system and is also useful to enhance the photocatalytic efficiency.With an increment of the amounts of Ag particles in the TiO2/ZFAB modified cementitious samples,the photocatalytic activities increased first and then decreased.The optimal Ag@TiO2/ZFAB modified cementitious sample reveals the maximum reaction rate constant for degrading benzene（9.91×10^-3 min^-1）,which is approximately 3 and 10 times higher than those of TiO2/ZFAB and TiO2 modified samples,respectively.This suggests that suitable Ag particles coupled with a ZFAB carrier could effectively enhance the photocatalytic effects and use of TiO2 in a cement system.Thus,ZFAB as a carrier could provide a potential method for a high efficiency engineering application of TiO2 in the construction field.

Development of engineered cementitious composites with local ingredients

In order to reduce the cost of high performance polyvinyl alcohol（PVA） fiber reinforced cementitious material（called engineered cementitious composites,ECC）,a ductile ECC material is developed using domestic PVA fibers along with other local ingredients,such as fly ash,cement and sand.In addition to the economic analysis of ECC,the four-point bending test and the optical microscope are employed to investigate the deflection capacity of ECC,its crack width and the occurrence of the self-healing phenomenon.The experimental results suggest that ECC made with domestic ingredients exhibits larger deformability and the average crack width is controlled around 60 μm.Furthermore,the self-healing behavior is observed in cracks of the specimens after cycles of wet and dry curing.The economic analysis shows that the cost of ECC can be greatly reduced via employing domestic PVA fibers.It is,therefore,feasible to produce low cost ECC material employing domestic PVA fibers,while simultaneously retaining high material ductility.

Studies on the Extraction Methods of Metagenomic DNA from Mud Volcano in Xinjiang

[Objective]To seek one effective extraction method of metagenomic DNA from mud volcano.[Method]The metagenomic DNA from mud volcano was extracted by CTAB extraction method,SDS-enzyme method,improved method,reagent kit method.The extraction of four kinds of methods were compared.[Result]The extracted rate in reagent sets method was the highest,next was improved method,the extracted quantity in SDS-enzyme method was maximum.DNA extracted by the improved method was diluted ten times for PCR.[Conclusion]Considering economy and purity,the improved method can be used as one effective extraction method of metagenomic DNA from mud volcano.

Influence of copper ions and calcium ions on adsorption of CMC on chlorite

The effects of copper ions and calcium ions on the depression of chlorite using CMC（carboxymethyl cellulose） as a depressant were studied through flotation tests,adsorption measurements,ζ potential tests and co-precipitation experiments.The results show that the electrostatic repulsion between the CMC molecules and the chlorite surfaces hinders the approach of the CMC to the chlorite while the presence of copper ions and calcium ions enhances the adsorption density of CMC.The action mechanisms of these two types of ions are different.Calcium ions can not adsorb onto the mineral surfaces,but they can interact with the CMC molecules,thus reducing the charge of the CMC and enhancing adsorption density.Copper ions can adsorb onto the mineral surfaces,which facilitates the CMC adsorption through acid/base interaction.The enhanced adsorption density is also attributed to the decreased electrostatic repulsion between the CMC and mineral surfaces as copper ions reduce the surface charge of both the mineral surfaces and the CMC molecules.

复杂井况条件下YY2侧钻水平井固井技术

YY1侧钻水平井完钻井深5609.00m,垂深3825.50m,水平位移1514.00m。该井3640.00-4160.00m井段狗腿度大,起钻全程倒划眼,卡钻频繁,下套管更是耗时227h,井下情况极其复杂。该井还存在油基钻井液固相含量高、井壁和套管壁清洗困难、封固段长(5069.00m)、顶底部温差大(85℃)、顶替效率难以保证等诸多固井难点。通过优化固井方案,采用了油基泥饼固化剂,制定了配套的固井技术措施。现场应用结果表明,该井固井质量优质率86.63%,为后续大型分段体积压裂奠定了较好的井筒基础。

Fracture suppression at steel/concrete connection zones by ECC

In order to avoid brittle fracture failure, a ductile engineered cementitious composite （ECC） was attempted in steel/concrete connection zones to replace normal concrete. The influence of the ECC material ductility on connection failure modes and structural performance was investigated via the pushout test of stud/ECC connection, the pullout test of two-dimensional anchor bolt/ECC connection and the finite element modeling （FEM）. The experimental results suggest that the micromechanically designed ECC with a tensile ductility 300 times that of normal concrete switches the brittle fracture failure mode to a ductile one in steel connection zones. This modification in material behavior leads to higher load carrying capacity and structural ductility, which is also confirmed in FEM investigation. The enhancement in structural response through material ductility engineering is expected to be applicable to a wide range of engineering structures where steel and concrete come into contact.

Fracture Properties of Cement Composites Reinforced with Steel Polypropylene Hybrid Fibres

Polypropylene fibres and three sizes of steel fibres reinforced concrete are discussed. The total fibres content ranges from 0 4%-0 95% by volume of concrete. A four point bending test is adopted on the notched prisms with the size of 100?mm×100?mm×500?mm to investigate the effect of hybrid fibres on crack arresting. The research results show that there is a positive synergy effect between large steel fibres and polypropylene fibres on the load bearing capacity in the small displacement range. But this synergy effect disappears in the large displacement range. The large and strong steel fibre is better than soft polypropylene fibre and small steel fibre in the aspect of energy absorption capacity in the large displacement range. The static usage limitation for the hybrid fibres concrete with “wide peak' or “multi peaks' load CMOD pattern should be carefully selected. The ultimate load bearing capacity and the crack width or CMOD at this load level should be jointly considered.

Detection of Sox Genes in Two Kinds of Loaches

The Sox genes of Misgurnus auguillicaudatus and Paramisgurnus dabryanuswere detected by PCR with two primer sets. The first primer set was specific to theconservative motif of human SRY gene. Four bands of 200, 550, 940 and 1 000 hp andthree bands of 200, 550 and 900 bp were presented in the PCR products of M.Auguillicaudatus and P. Dabryanas, respectively. Results from Southern blottingindicated that the 200 and 550bp bands are positive. This study also used thedegenerate primer within the HMG-box. With the genomic DNA as template, fourbands were observed with the lengths of 220, 550, 700 and 1500 bp in P. Dabryanus; butfour bands of 220, 530, 570 and 1500hp in M. Auguillicaudatus. It is suggested that thelength divergence in PCR products were due to different sizes of nitrons in the HMG boxes. In addition no sex-specific band was found in these two species.

Flexural behaviors of steel reinforced ECC/concrete composite beams

An engineered cementitious composite （ECC） is introduced to partially substitute concrete in the tension zone of a reinforced concrete beam to form an ECC/reinforced concrete （RC） composite beam, which can increase the ductility and crack resisting ability of the beam. Based on the assumption of the plane remaining plane and the simplified constitutive models of materials, the stress and strain distributions along the depth of the composite beam in different loading stages are comprehensively investigated to obtain calculation methods of the load-carrying capacities for different stages. Also, a simplified formula for the ultimate load carrying capacity is proposed according to the Chinese code for the design of concrete structures. The relationship between the moment and curvature for the composite beam is also proposed together with a simplified calculation method for ductility of the ECC/RC composite beam. Finally, the calculation method is demonstrated with the test results of a composite beam. Comparison results show that the calculation results have good consistency with the test results, proving that the proposed calculation methods are reliable with a certain theoretical significance and reference value.

Flexural behaviors of double-reinforced ECC beams

In order to investigate the flexural behaviors of engineered cementitious composites （ECC）, theoretical and experimental researches are done on flexural doublereinforced ECC beams. Based on the assumption of the plane section remaining plane in bending and simplified constitutive models of materials, the calculation methods of load carrying capacities for different critical stages are obtained. Then, these calculation methods are demonstrated by comparing the test results with the calculation results. Finally, based on the proposed theoretical formulae, the effects of the compression strength, compression strain and tension strength of ECC, and the reinforcement ratio on the flexural behaviors of double-reinforced ECC beams are analyzed. The calculated and measured results are in good agreement, which indicates that the theoretical model can be used to predict the momentcurvature response of steel reinforced ECC beams. And the results of parametric studies show that the increase in the compression strength of ECC can greatly improve the flexural performance of beams; the increase in the ultimate compression strain can significantly improve the ultimate curvature and ductility, but has little effect on the load bearing capacity of beams. little effect on the flexural The tensile strength of ECC has behaviors of ECC beams. The increase in the steel reinforcement ratio can lead to significant improvement of the load bearing capacity and the stiffness of beams, but a degradation of the ductility of beams. The theoretical model and parameter analysis results in this paper are instructive for the design of steel reinforced ECC beams.

Optimization of a digested sludge-derived mesoporous material as an efficient and stable heterogeneous catalyst for the photo-Fenton reaction

The anaerobic digestion of sludge has recently received increased interest because of the potential to transform organic matter into methane‐rich biogas. However, digested sludge, the residue produced in that process, still contains high levels of heavy metals and other harmful substances that might make traditional disposal difficult. We have devised a facile method of converting digested sludge into a mesoporous material that acts as an effective and stable heterogeneous catalyst for the photo‐Fenton reaction. A comparison of the removal of rhodamine B under different conditions showed that FAS‐1‐350, which was synthesized by mixing the digested sludge with a 1 mol/L（NH4）2Fe（SO4）2 solution followed by calcination at 350 °C, exhibited the best catalytic activity owing to its faster reaction rate and lower degree of Fe leaching. The results indicate that Fe^（2＋）‐loaded catalysts have significant potential to act as stable and efficient heterogeneous promoters for the photo‐Fenton reaction, with better performance than Fe^3＋‐loaded catalysts because the Fe（II）/Fe（III）compounds formed in the calcination process are necessary to sustain the Fenton reaction. This protocol provides an alternative, environmentally friendly method of reusing digested sludge and demonstrates an easily synthesized mesoporous material that effectively degrades azo dyes.

Mechanical behaviors of steel reinforced ECC / concrete composite columns under combined vertical and horizontal loading

In order to improve the load capacity, seismic performance and performance-cost ratio of the columns, the concrete at the base of reinforced concrete （RC） columns is substituted with engineered cementitious composites （ECC） to form ECC/RC composite columns. Based on the existing material properties, the mechanical behaviors of the ECC columns, ECC/RC composite columns and RC columns were numerically studied under combined vertical and horizontal loading with the software of ATENA. Then, the failure mechanism of ECC columns and ECC/RC composite columns were comprehensively studied and compared with that of the RC columns. Then, the effects of the height of the ECC, the axial compression ratio, and the transverse reinforcement ratio on the mechanical behaviors of the composite or the ECC column are studied. The calculation results show that the ultimate load capacity, ductility and crack resistance of the ECC or ECC/RC composite columns are superior to those of the RC columns. The ECC/RC composite column with a height of the ECC layer of 1.2h （ h is the height of the cross section） can achieve similar mechanical properties of a full ECC column. With high shear strength, ECC can undertake the shear force and significantly reduce the amount of stirrups, avoiding construction issues and promoting its engineering application.