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1.
焦油裂解时氧化钙失活的活性再生特性研究   总被引:1,自引:0,他引:1  
在固定床反应器上,以焦油的两种主要组份苯和甲苯为对象,对氧化钙失活后通过燃烧实验研究其催化活性的再生特性,测定了再生氧化钙条件下的裂解反应动力学参数.实验结果表明,通过空气条件下燃烧,氧化钙的活性得到部分再生,相同温度下,再生条件下气态裂解产物减少.  相似文献   

2.
一种循环床循环灰条件下焦油组分的催化裂解   总被引:5,自引:0,他引:5  
以循环流化床锅炉循环灰为热载体、部分气化产生的半焦为锅炉燃料的煤的部分气化技术中,降低焦油产率、提高煤气产率是一个关键。在固定床反应器实验台上实验研究了一种循环流化床锅炉循环灰条件下焦油的两种主要组分苯和甲苯的催化裂解反应特性,测定了裂解反应动力学参数,探讨了循环灰的催化机理,实验结果表明,与石英砂条件下相比,循环灰极大地促进了焦油的裂解程度,气态裂解产物总量提高。  相似文献   

3.
生物质焦油是生物质热解和气化过程中不可避免的副产物,并且在生物质应用过程中存在有害的影响,因此对于生物质焦油转化的研究受到广泛的关注。本文在试制开发低流阻高强度的蒸汽重整整体式催化剂的基础上,以苯和甲苯作为焦油的模型化合物,在管式反应器上研究了该催化剂作用下,温度、蒸汽量对焦油催化转化以及裂解气体成分的影响;并实验研究了催化剂作用下温度和水碳摩尔比S/C对甲烷转化率的影响。实验发现,苯和甲苯的转化率都随温度的提高而升高。甲苯和苯在裂化温度900℃,S/C=2时整体式催化剂催化作用下转化率分别达到94.1%和77.1%;在600℃时实现了甲烷气体的高效转化;蒸汽量的增加有助于裂解气体成分的调整,同时也促进了消碳反应的进行。  相似文献   

4.
焦油裂解反应对循环灰催化作用的影响   总被引:2,自引:0,他引:2  
以循环床锅炉循环灰为热载体、部分气化产生的半焦为锅炉燃料的煤的部分气化技术中,循环灰对降低焦油产率、提高煤气产率是有利的。以焦油的两种主要组份苯和甲苯为对象,用固定床反应器实验研究了焦油裂解过程中反应对一种烟煤形成的循环灰的催化活性的影响,测定了该种循环灰的失活系数,探讨了失活机理。实验结果表明,随着积碳量的增加,循环灰的比表面积和空隙率减小,裂解反应速率下降,裂解产物中碳产率增加。  相似文献   

5.
以秸秆热解产生的焦油为原料,在固定床反应器实验台上进行了催化裂解实验,研究了反应温度和催化剂种类对生物质焦油的裂解反应产物———二次焦油成分的影响规律。在高铝砖作为催化剂作用下,随着温度的升高,二次焦油构成有芳香化的趋势,多环芳烃的种类和含量都在增加。反应温度的提高有利于焦油的深度转化,二次焦油产率降低;但是高温下生成的二次焦油芳化程度更高,更容易引起催化剂积炭失活。当反应温度为900℃时,碱性催化剂白云石和石灰岩作用下二次焦油成分相似,以复杂的大分子环烃为主,而且焦油成分种类减少到10种左右;酸性催化剂高铝砖作用下焦油成分仍然很复杂,有将近30种,除了含有大分子环烃外,还含有部分石蜡烃,芳香族种类很多,多以双环、三环以及四环的形式存在。  相似文献   

6.
导向喷动流化床生物质快速裂解制液体燃料   总被引:12,自引:0,他引:12  
在冷模试验得到的优化的结构参数基础上,建立了一套生物质最大处理量为5kg/h的导向管喷动流化床生物质裂解反应器。反应在常压和440~520℃进行,以木屑为生物质原料,二氧化碳和氮气为喷动气或流化气,沙子为流化介质。结果表明该喷动流化床反应器可用于生物质的快速裂解。在400~480℃,液体产率随温度增加而上升,高于480℃时,二次反应的加剧又导致液体产品产率下降。固体和气体的产率则随温度的升高而减少。喷动气和流化气流量的增加均强化了反应器内的传热,并使生物质初始裂解产物的停留时间减少,二次反应进行程度减弱。在适当的裂解条件下液体产率可达73.2%,此时气体和焦的产率分别为12.8%和14.0%。所得液体产品为单一相液体,含水约30%,可用于燃烧。与流化床相比,喷动流化床作为生物质快速裂解反应器可明显提高液体产率。  相似文献   

7.
为解决焦油裂解中流化床气化技术的问题,以焦油的两种主要组份苯和甲苯为对象,利用固定床反应器对一种烟煤形成的循环灰失活后通过燃烧其催化活性的再生特性进行了实验研究,测定了再生循环灰条件下的裂解反应动力学参数。实验结果表明,通过空气条件下燃烧,循环灰的活性得到完全再生,再生前后气态裂解产物变化很小。该结果对循环床气化具有重要的指导意义。  相似文献   

8.
为了提高煤在分级转化中的高效洁净利用,建立了煤加压热解实验系统.以陕西黑龙沟煤为对象,研究了不同温度(500~700℃)、压力(0.1~0.5 MPa)、气氛(N2与煤气)、粒径(0~3mm与0~6 mm)对低温热解焦油、煤气产率和品质的影响规律.结果表明,随着温度升高,焦油产率先增加后减小,在温度为600℃时达到最高,煤气产率逐渐增加.随着压力的增加,焦油产率在N2气氛下降低,煤气气氛下升高;而热解煤气产率在N2气氛下升高,煤气气氛下降低;大颗粒煤热解焦油产率高于小颗粒煤的热解产率,但当压力达到0.5 MPa时,热解焦油与煤气产率几乎不受粒径影响.升高压力虽降低了热解煤气中CO与H2的含量,但促进更多轻质碳氢化合物(如CO2,CH4,C2H4,C2H6)的析出,因此提高了热解煤气热值,同时煤焦油品质也因焦油中苯、甲苯、苯酚及萘的实际收率增加而提高.  相似文献   

9.
合成了一种草酰胺单核Cu(Ⅱ)配合物,并通过红外光谱、核磁共振氢谱、元素分析等手段对其进行表征。以分子氧为氧源,研究了其与NHPI协同催化氧化甲苯的性能,考察了温度、时间、氧压力等因素对反应的影响。结果表明,当反应温度为80℃,反应时间为10h,氧压力为0.5MPa时,甲苯的转化率和苯甲酸的产率分别达到84.1%和76.8%。与传统的甲苯催化氧化体系相比,甲苯的转化率和苯甲酸的产率均有了较大的提高。该催化体系具有反应条件温和、选择性高等优点。  相似文献   

10.
为掌握橄榄石在焦油转化过程中的作用规律,采用实验的方法研究橄榄石及其主要化学组成催化重整煤焦油的模型物甲苯.实验结果表明:橄榄石能大大促进甲苯生成气体产物.主要化学组成中MgO促进甲苯转化为气体产物的能力最强,Fe_2O_3次之,CaO不能促进气体产物的生成.甲苯在石英砂上反应生成的气体不饱和烃可能是通过甲苯侧链甲基的脱氢、聚合产生,由苯开环裂解产生的可能性小.煅烧后的橄榄石中除Fe_2O_3外,其他微量化学组成Al_2O_3、NiO可能起了较大的催化作用.氧化钙、氧化铁、氧化镁等化学组成都能降低甲苯水蒸气重整过程中的积碳速率.积碳速率由大到小的顺序是橄榄石石英砂氧化铁氧化钙氧化镁.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
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   

16.
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   

17.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

18.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

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