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71.
液态CO2相变致裂强化瓦斯预抽试验研究 总被引:1,自引:0,他引:1
针对单一低透气性煤层瓦斯含量高、预抽效果不理想的情况,采用液态CO2相变致裂技术,在穿层钻孔中利用瞬间产生的高压CO2气体冲击煤体,产生大量裂隙并促使裂隙发育、扩展,以达到提高煤层透气性的目的.在河南焦煤能源有限公司九里山16051底抽巷进行的试验表明:液态CO2相变致裂技术可有效提高瓦斯抽采效果,试验后平均抽采流量0.057 m3/min,是试验前平均流量的4.3倍,是相同抽采时间内水力冲孔措施平均抽采流量的2.3倍;抽采体积分数也有所提升;在试验考察期内流量衰减系数降低到0.046 d-1,增透效果显著. 相似文献
72.
水平井是高尚堡浅层断块油藏的主要开采方式,在水平井开发过程中易形成边底水突进、水窜、水淹,油井含水上升速度快,导致油井产能下降,严重影响油田的开发效果。针对水平井开发后期产能下降的问题,采用了CO2吞吐增油技术。其主要技术原理为:在地层温度条件下CO2能快速溶于原油中,使原油膨胀,改变原油的物性,大幅度降低原油黏度,降低油水界面张力,增加溶解气驱的能量,进而达到油井增产的目的。34井次的现场应用结果证实,水平井单井日产油量由1.72t增加到4.88t,含水率由95.00%下降到51.45%,控水增油效果显著。 相似文献
73.
为了研究5Cr套管钢在不同CO2分压下的腐蚀特性,进行了5Cr套管钢高温高压腐蚀失重和高温高压电化学试验,并采用XRD、SEM和EDS等手段对其腐蚀产物进行微观分析。结果表明,在高温高压腐蚀环境下随着CO2分压从低到高,其表面点蚀坑的深度和直径均无明显变化,而点蚀速率则出现逐渐减小的趋势;其腐蚀产物膜由Cr(OH)3、FeCO3和CaCO3共同组成,且随着CO2分压的升高Cr的富集量逐渐增加;在电化学测试中,随着CO2分压的不断升高,5Cr套管钢表现出半钝化特征,产物膜逐渐增厚且致密,且极化电阻逐渐增大,阳极反应受到抑制,电化学反应阻力增大,其抗局部腐蚀能力不断提高。 相似文献
74.
利用薄片鉴定、扫描电镜、阴极发光及碳氧同位素分析等手段,对莺歌海盆地LD10区新近系梅山组-黄流组高温-超压-高CO2背景下的储层成岩作用特征及其对孔隙的影响进行了系统研究。研究结果表明: ①莺歌海盆地LD10区新近系梅山组-黄流组储层发育重力流沉积,岩性以中-细粒长石岩屑石英砂岩为主,储层物性以特低-低孔、特低渗特征为主。②压实、胶结和溶蚀作用是研究区主要的成岩作用类型。超压对黏土矿物的转化及石英次生加大具有明显抑制作用,并在一定程度上保护了原生孔隙。富含CO2的高温流体不仅造成了黏土矿物的异常转化,同时促进了溶蚀作用发生,增加了次生孔隙。③研究区黄二段储层的成岩演化序列为: 菱铁矿胶结→石英次生加大→绿泥石胶结→长石淋滤溶蚀→高岭石形成→早期方解石胶结→早期白云石胶结→长石溶蚀→方解石溶蚀→伊利石大量生成→晚期铁方解石、铁白云石形成。④总体上,压实作用使孔隙度减少了45.30%~62.93%,胶结作用使孔隙度减少了1.65%~35.01%,溶蚀作用使孔隙度增加了0.72%~8.00%。其中,黄流组中下部砂岩储层受到了超压保护和CO2溶蚀作用的双重影响,物性较好,钻井过程中应考虑高CO2风险。 相似文献
75.
Guopeng Han Na Yu Dahuan Liu Guangren Yu Xiaochun Chen Chongli Zhong 《American Institute of Chemical Engineers》2021,67(2):e17112
Development of materials with excellent separation performance remains an ongoing challenge in separation science and technology. Herein, a novel strategy was proposed to gradually enhance gas separation performance in micro/nano-materials, by constructing a shell-interlayer-core structure using ionic liquid (triethylenetetramine lactate, [TETA]L) and zeolitic imidazolate framework (ZIF-8). Such structure includes outer [TETA]L shell, interlayer of ZIF-8, and inner [TETA]L core, endowing the composite with more evident molecular sieving separation for CO2 mixtures than the reported materials. A high CO2 adsorption amount (1.53 mmol/g at 298 K and 1.0 bar) is maintained, while the uptakes for CH4 and N2 are very low. Corresponding ideal adsorbed solution theory selectivities are 260–1,990 and 1,688–5,572 for CO2/CH4 and CO2/N2 mixtures at the range of tested pressures. In addition, the separation performance can be controlled by varying the shell-interlayer-core structure with IL inside, outside or on both sides of ZIF-8 and the thickness of outer shell. 相似文献
76.
Yi Lu Rui Li Rogerio Manica Qingxia Liu Zhenghe Xu 《American Institute of Chemical Engineers》2021,67(1):e17033
Interfacial properties are of critical importance to various separation applications. In heavy oil recovery, for example, a low oil–water interfacial tension (IFT) benefits the separation of heavy oil from their host rocks, which becomes problematic in the later stage of oil–water separation. CO2-responsive surfactants were investigated to enhance the overall heavy oil recovery by switching their interfacial activity to the desired state in each stage. The surfactants at interfacially active state greatly enhanced the separation of heavy oil from hosting solids, as demonstrated by measuring contact angle and oil liberation using a custom-designed on-line visualization system. Meanwhile, the resulting heavy oil-in-water emulsions could also be easily demulsified by the bubbling of CO2 gas, which switched off the interfacial activity of the surfactants. Furthermore, CO2-responsive surfactants could be partially recycled in process water to improve sustainability, making CO2-responsive surfactants to be promising chemical aids in heavy oil production and many other vital industries. 相似文献
77.
Xiao Fan Baitang Jin Shoujie Ren Shiguang Li Miao Yu Xinhua Liang 《American Institute of Chemical Engineers》2021,67(11):e17353
The roles of interaction between two catalyst components in CuO–ZnO–ZrO2–Al2O3 (CZZA)/HZSM-5 bifunctional catalyst for dimethyl ether (DME) synthesis via carbon dioxide hydrogenation were investigated. It was found that CZZA catalyst showed excellent stability during methanol (MeOH) synthesis for 100 h, while there was a severe loss of catalytic activity in the bifunctional catalyst for DME synthesis. Hence, the effects of different degrees of intimacy of two catalyst components were studied for DME synthesis, including mixed and separated modes. For the mixed mode, the particle size of catalysts and the amount of reaction intermediates were proven to influence the catalyst deactivation. For the separated mode, the catalysts showed rapid deactivation within a short time. Various characterizations indicated that the remarkable deactivation of separated mode was mainly caused by the decrease of copper active centers (e.g., sintering and oxidation) and blockage of acid sites via increased coke deposition on HZSM-5. 相似文献
78.
Weixin Guan Xiaochen Yang Chenyuan Dong Xiaoming Yan Wenji Zheng Yuan Xi Xuehua Ruan Yan Dai Gaohong He 《应用聚合物科学杂志》2021,138(8):49895
The packing pattern of two-dimensional (2D) sheet-like fillers in membranes is relatively random, leading to the unfavorable permeability from tortuous diffusion pathway. A new strategy that using prestructured materials with uniform channels as fillers was proposed. In this work, Ti3AlC2 is etched to prepare multilayered MXene (m-MXene), the channels aggregate as a whole unit, ensure the impossibility of ineffective packing compared with traditional individual sheets, largely facilitating the selective permeation. Then, the m-MXene/Poly (amide-6-b-ethylene oxide) (Pebax) MMMs are synthesized. SEM images demonstrate the accordion shaped structure of filler, which is the multi-channels laminates. Furthermore, the results of gas permeation test exhibit enhanced performance of m-MXene/Pebax MMMs. MMM with 0.5 wt.% m-MXene behaved best, CO2 permeability of 86.22 Barrer as well as CO2/N2 selectivity of 104.85, transcending the Robeson upper bound (2008). Having distinct enhancement for CO2 separation, the m-MXene/Pebax MMMs in this work offer prospective practical applications. 相似文献
79.
In this study, biomimetic sodium alginate (SA)/silk fibroin (SF) scaffolds were successfully fabricated by supercritical CO2 technology. The SA/SF scaffolds exhibited an interconnected porous and extracellular matrix (ECM)-like nanofibrous structures. Moreover, the SA microparticles were embedded in the SF scaffolds. Increasing the content of SA microparticles could improve tensile strength and compressive strength of the SF scaffolds and reduce the porosity of the SF scaffolds. The addition of the SA microparticles could also regulate the degradation rate of the SA/SF scaffolds. Furthermore, the results of in vitro biocompatibility evaluation, indicated that the SA/SF scaffolds exhibited no obvious cytotoxicity and higher cell adhesion ability and were more favorable for L929 fibroblasts proliferation than pure SF scaffolds. Therefore, the SA/SF scaffolds with ECM-like nanofibrous and interconnected porous structure have potential application in skin tissue engineering. 相似文献
80.
提出了一种化学链制氢(chemical looping hydr-ogen,CLH)与固体氧化物燃料电池(solid oxide fuel,SOFC)相结合的新型发电系统,并利用?分析法研究了该新型发电循环。在该系统中,氢气由化学链制氢子系统产生,循环材料是FeO和Fe3O4。固体氧化物燃料电池的余热在化学链制氢子系统中被利用,并通过化学链中的还原反应转化为化学能。在?平衡的基础上进行了系统关键参数的分析,并对化学链关键过程进行了研究。同时,由于化学链可以实现CO2无能耗的分离,新系统可以在分离二氧化碳的条件下实现净效率61.2%。?分析法表明,新系统获得高性能的主要原因是废热的梯级利用和高效制氢。结果表明,这种新型的热循环是实现甲烷化学能高效利用同时实现低能耗分离CO2的有效途径。 相似文献