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1.
应用压团、焙烧方法,结合矿相分析,研究燃料配比、焙烧时间、焙烧温度、铁矿化学成分和铁矿粒度等因素对铁酸钙形成的影响。研究结果表明:随着燃料配比增加、焙烧时间延长及焙烧温度升高,各铁矿与氧化钙生成铁酸钙的量先增大后减小;适宜的燃料配比为0.5%,焙烧时间为13min,焙烧温度为1250~1280℃;当铁矿粒度较大时,SiO2含量越高,生成铁酸钙的量越多;当铁矿粒度较小时,SiO2含量越高,生成铁酸钙的量就越少;粒度范围越宽的铁矿,生成铁酸钙的量越多。  相似文献   

2.
报导了添加剂CaCl3在天青石还原焙烧中的反应行为;并从试验中寻找出了使用该添加剂的最佳反应条件。实验结果表明:CaCl2用量为0.5%-1%,反应温度为1150-1200℃,反应时间为30min,矿:煤为1:0.6,矿、煤粒度为20-40目时,可使SrCO3生产的转化率最高。  相似文献   

3.
对生物质磁化鲕状赤铁矿石进行研究,包括磁化温度、磁化时间、生物质用量以及赤铁矿石粒度对磁化效果的影响.在磁化温度为600℃,赤铁矿石与生物质的质量比为10:2的情况下,利用生物质热解产生的气体和焦油在30 min内可以完全磁化粒度为0.074 mm (>72.5%)的赤铁矿石,验证了生物质替代煤基还原剂进行磁化焙烧具有一定的可行性.此外,矿石粒度对磁化焙烧还原度的影响比较大,矿石粒度越大,完全磁化所需时间越长.根据生物质还原剂的特点,适当地减小矿石粒度可以有效改善赤铁矿石的磁化性能.  相似文献   

4.
以湖北鄂西某高磷鲕状赤铁矿为研究对象,采用还原焙烧-弱磁选方法进行试验,并用黑曲霉对磁选后精矿进行微生物浸出脱磷研究.试验结果表明,正交实验得出各因素对精矿品位的影响顺序从大到小依次为焙烧温度、焙烧时间、还原剂比例、磨矿粒度.最佳焙烧-弱磁选条件为焙烧温度900℃、焙烧时间25 min、还原剂配比6%、磨矿粒度-0.074 mm95.08%,在此条件下获得精矿品位57.25%、回收率90.20%的较好的选别指标.黑曲霉对精矿中的磷元素具有较强的脱除能力,微生物浸出作用8d后,在较低的矿浆浓度下矿石的脱磷率为79.68%,矿石中的含磷量由0.85%降低到0.17%.该研究为微生物用于铁矿石的脱磷提供了理论依据.  相似文献   

5.
黄自新  陈长林 《科技信息》2012,(29):418-420
选择钙法氧化焙烧一酸浸工艺流程从石煤型钒矿石中酸浸提钒,克服了钠化焙烧过程中H2S、Cl2等有毒有害气体的产生。试验表明,焙烧温度、酸的浓度、浸出温度、浸出时间、液固比是影响钒浸出率的重要因素。通过矿石物料粒度、氧化钙添加量、焙烧温度、焙烧时间、浸出温度、浸出时间、酸的浓度、浸出液固比等条件实验,获得了钒79%的浸出率。在此基础上提出了安康市石煤型钒矿综合开发利用的框架思路。  相似文献   

6.
毒重石钡矿高温分解特性   总被引:3,自引:1,他引:3       下载免费PDF全文
提出了经济合理地开发利用毒重石钡矿资源生产钡产品的方法,研究了毒重石钡矿高温分解的机理,探寻采用高温焙烧使毒重石钡矿分解的最佳条件,为毒重石钡矿的利用开辟新途径。理论分析认为,毒重石钡矿在900℃左右开始分解,1200℃开始大量分解,1300℃约有90%的BaCO3已经分解。并通过一系列实验对焙烧条件作了比较细致的,认为毒重石钡矿高温焙烧的适宜条件为:粒度6-9mm、焙烧时间3h、焙烧温度控制在1300℃以内。  相似文献   

7.
氧化焙烧法处理高硫铝土矿,具有操作简便、能够同时去除矿石中有机物的优点,但仍存在着能耗高以及一水硬铝石脱水造成氧化铝溶出困难等问题.本研究基于黄铁矿和一水硬铝石的热分析和恒温焙烧实验结果,发现黄铁矿脱硫与一水硬铝石脱水反应起始温度接近,但脱硫反应速率慢而脱水反应速率快,从而提出通过降低焙烧反应温度、延长反应时间来提高脱硫率、抑制脱水率的处理工艺.通过模拟样品和实际样品的焙烧条件优化实验,确定硫含量为3.8%的铝土矿最佳脱硫处理条件为:空气气氛下,焙烧温度460~470℃,焙烧时间15~20min,处理后铝土矿含硫量低于0.5%,符合拜耳法氧化铝生产工艺的要求.  相似文献   

8.
对三水铝石矿进行低温焙烧预处理,利用XRF,XRD和SEM等检测手段系统研究了焙烧温度、焙烧时间对三水铝石矿脱水脱碳与焙烧矿氧化铝溶出性能的影响及其作用机理.结果表明:焙烧后矿石质量大幅减少,矿石表面有明显的裂纹,呈片层状结构;三水铝石相减少,并逐渐向一水软铝石转变,同时针铁矿转变为赤铁矿;当焙烧温度为400℃,焙烧时间为30 min时,矿石中结晶水的质量分数为7.54%,脱水率为62.52%,碳的质量分数低至0.11%,脱碳率为85.73%;焙烧矿在溶出温度145℃、溶出时间30 min、循环母液苛性碱的质量浓度为170 g/L时,氧化铝实际溶出率为81.51%,高于原矿的氧化铝溶出率.焙烧矿溶出动力学结果表明氧化铝溶出过程中主要受内扩散控制,表观活化能为42.71 kJ/mol.  相似文献   

9.
以钒含量较高的RMS-8流化催化裂化催化剂为原料,考察了氧化法和酸洗法的脱钒效果。结果表明,脱钒率不仅与洗涤条件有关,而且与氧化焙烧的条件有关。氧化焙烧时间相同时,不同洗涤溶液的脱钒效果也不同,其中草酸和H2O2混合溶液脱钒效果较好;脱钒率随洗涤次数的增加而增加,氧化焙烧时间和温度对脱钒效果也有显著影响。在其他条件相同的情况下,氧化时间越长,氧化温度越高,脱钒率也越高。从活性恢复的角度看,在脱钒率较低时,催化剂的活性即可得到大部分恢复。但再进一步提高脱钒率,对催化剂活性的恢复影响不大。  相似文献   

10.
焙烧过程中阴极类型对阴极热场分布的影响   总被引:3,自引:0,他引:3  
以有限元分析软件ANSYS为平台,建立了160kA铝电解槽焦粒焙烧时的三维1/4整槽模型;对3种典型阴极炭块(半石墨质、半石墨化和石墨化)在给定焙烧条件下的热场分布进行了仿真研究。结果表明:由于这3种炭块的电导率和导热系数依次增大,因此,在相同的焙烧条件下达到焙烧终点(阴极最高温度为1030℃)时,阴极的温度分布依次变均匀;半石墨化和石墨化阴极与半石墨质阴极相比,其最大温差分别降低了133℃和232℃;阴极表面平均温度分别提高了34℃和57℃;周边糊的平均温度分别提高了77℃和126℃;900℃以上温度所占面积则从52.4%分别提高到63.0%和70.5%;达到相同终点的焙烧时间从96h分别增加到132h和205h。当焦粒层厚度从20mm增加到30mm时,石墨化炭块的焙烧时间从205h缩短到90h,虽然焙烧效果有所下降,但仍然显著优于其他2种炭块在焦粒层厚度为20mm时的焙烧效果。  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.
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   

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.
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   

15.
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   

16.
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   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
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   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
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   

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