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1.
对曲靖烟煤和南露天褐煤进行超临界CO2/NMP(N-甲基吡咯烷酮)混合溶剂萃取,其中曲靖烟煤萃取率可达到14%(干基),而南露天褐煤萃取率仅有4%(干基)左右。对萃余煤进行表征,结果表明:超临界CO2/NMP混合溶剂对煤中富含羟基及脂肪类物质有良好的萃取性能,经过萃取,两种煤中微晶结构的堆垛高度都有所减小,溶胀度都降低。南露天褐煤的比表面积减小,而曲靖烟煤的比表面积轻微增大。溶剂对煤颗粒表面有腐蚀作用,萃取后两种煤的气化性能得到改善,其中曲靖烟煤改善的程度更大。  相似文献   

2.
利用水对神府东胜煤样进行了超声萃取,通过GC/MS分析研究了其水萃取物的有机物的族组成,用FTIR分析其原煤及水萃余煤,比较它们在二硫化碳(CS2)和N-甲基吡咯烷酮(NMP)(体积比1∶1)混合溶剂中萃取率的不同。结果表明:水萃取物有机成分中含有多种含杂原子成分及烷烃;超声水萃取的萃余煤在CS2/NMP的混合溶剂中的萃取率大于原煤;红外光谱分析显示超声水萃取使原煤部分盐类的去除及煤中分子间氢键等的破坏可能是混合溶剂萃取率增高的原因。  相似文献   

3.
依次用石油醚、CS2、丙酮和甲醇4种溶剂通过索式萃取对霍林郭勒褐煤(HL)的次氯酸钠(NaOCl)水溶液氧化残渣进行分级萃取.发现总的萃取率大于原煤萃取率.所得各级萃取物用GC/MS分析检测,E1和E2馏分中分别检测到85种和23种化合物,E3和E4萃取馏分中无GC/MS可检物质.结果表明煤的次氯酸钠氧化有助于提高煤的萃取率,索式萃取可实现氧化残渣的族组分分离.  相似文献   

4.
在半连续实验装置上,以水为溶剂对大雁褐煤进行了超临界萃取实验。考察了压力、终温对萃取过程产率及产品组成的影响。结果表明,用水萃取褐煤在合适条件下,可得到高的转化率及萃取物产率;萃取压力增加,转化率和萃取物产率增加;萃取终温增加,转化率增加,但增加量主要为气体和轻油组分。在超临界条件下,萃取物主要馏分为予沥青烯。萃取过程中气体产率约为20%,其主要组分为CO2;经萃取后的褐煤(约占原煤50%),具有比原煤高的碳含量,低挥发分及氧含量,几乎不含水,可作为气化或燃烧的原料。  相似文献   

5.
作者通过对部分二元复合溶剂混合热、溶剂与煤的作用热、抽提率的测定,找出了抽提率与作用热之间的关系。结果表明,在所试验的范围内,以溶解度参数作为选择抽提煤的溶剂的依据,仅适用于烟煤,不适用于褐煤;以煤与溶剂的作用热为依据选择溶剂,同时适用于烟煤和褐煤。  相似文献   

6.
先用溶剂对柴里煤进行彻底萃取,再用双氧水将萃余煤进行氧化,对原煤、萃余煤和氧化残煤用热重和红外进行分析.结果表明:萃余煤和氧化残煤的内部结构发生变化,原煤的结构最复杂,萃余煤中的小分子相对减少了很多,但氧化残煤内部又有小分子出现,说明氧化能断开煤分子内部的某些键.由红外光谱分析得出煤是一种含有多官能团的复杂的混合物,萃取和氧化使煤中的有机物发生了改变,两者产生的变化是有一定的差别的,但是由各谱图吸收峰可以看出,萃取或氧化前后煤中的官能团种类变化并不大,其中某些物质的含量却发生了较大的变化.  相似文献   

7.
在微波辅助下,考察了萃取温度、溶剂种类、辐射时间对萃取率的影响。对神府煤而言,采用乙醇、丙酮和四氢呋喃为溶剂的较佳萃取温度分别为393K、373K、373K且四氢呋喃的萃取率高于丙酮和乙醇。采用相同的溶剂对五种不同变质程度煤的微波辅助萃取结果显示,变质程度相似的煤在相同萃取条件下萃取率不同。对神府煤和其四氢呋喃萃余煤进行了红外分析。  相似文献   

8.
本文在课题组已有的离子液体对煤进行溶胀预处理的研究基础上,进一步研究了多种含离子液体的二元混合溶剂.结果表明,[Bmim]Cl+NMP对神华褐煤的溶胀效果最佳.通过研究二元溶剂中[Bmim]Cl的体积分数、溶胀温度及时间对煤的溶胀度及其电化学还原反应的影响,发现[Bmim]Cl的体积分数为0.5时,煤的溶胀度较高.神华煤在[Bmim]Cl+NMP中溶胀12h即可达到平衡.提高温度不仅可以缩短达到溶胀平衡所需的时间,还可以进一步破坏煤的结构,提高溶胀度.神华褐煤在150℃下溶胀12h,溶胀度可达到3.93.通过二元溶剂[Bmim]Cl+NMP对煤的溶胀处理能提高煤电解加氢还原的反应活性,有利于提高煤的液化率,使电解液化率从31.66%提高到62.27%.  相似文献   

9.
本文系统地研究了无烟煤的溶胀行为,及其对无烟煤电催化加氢液化的促进效果.研究结果表明,作为高阶煤的无烟煤,其溶胀行为和低阶煤(褐煤)不同,非极性溶剂的溶胀效果优于极性溶剂.在所研究的多种有机溶胀剂中,苯对无烟煤的溶胀效果最佳,60℃下溶胀度可达4.01.研究发现,在溶胀过程中溶胀剂分子在煤大分子网络结构中的渗入可使无烟煤体积膨胀,促进煤结构疏松化以及使煤颗粒变小;同时溶胀剂分子与煤大分子的相互作用力可以破坏原煤中的部分化学键结构并产生小分子物种,进一步削弱了煤大分子的网络结构,促进煤的溶胀度提高.研究还表明,引入溶胀促进剂Fe(NO3)3可与有机溶胀剂产生协同溶胀作用从而进一步促进煤的溶胀,提高煤的溶胀度.对于无烟煤的溶胀处理,有利于其电催化加氢液化反应的活性,大大提高了无烟煤的电解液化率,使其电解液化率由原煤的32.04%提高到63.19%.  相似文献   

10.
年轻煤溶剂溶胀后加氢液化性能的研究   总被引:2,自引:0,他引:2  
以山东龙口局洼里煤、新汶局孙村煤为研究用煤。首先进行溶剂溶胀,实验表明吡啶溶剂的溶胀作用最强。溶胀率指标表明溶胀煤结构变得疏松;热重分析表明溶胀煤热分解活性增强。然后对原煤和溶胀煤进行加氢液化实验,通过煤的转化率、液化油产率和煤气产率等指标,表明洼里原煤、洼里溶胀煤和孙村溶胀煤具有良好的加氢液化性能,各溶胀煤比其原煤的油产率均有显著提高。对于所实验煤的基本液化条件进行了实验探索。  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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