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1.
急倾斜煤层地下气化数学模型的研究   总被引:5,自引:1,他引:5  
煤炭地下气化产气过程与气化炉体的温度分布和渗流条件密切相关。根据急倾斜煤层赋存条件和气化过程的特点,建立了急倾斜煤层地下气化数学模型。介绍了模型参数的确定方法,采用控制容积方法对模型进行了求解,并在模型实验的基础上,对计算结果进行了分析。从温度场分布来看,计算值略高于实测值,各测点相对误差基本均在10%以内。根据模拟计算结果,随着气化通道长度增加,煤气热值提高,但在还原区以后,提高的幅度减小,温度场对煤气热值产生显著影响。由于受温度的影响,在高温区,煤气组分浓度场实测值的变化梯度大于计算值。结果表明,模拟值与实验值能够较好地相吻合,说明对急倾斜煤层地下气化温度场和浓度场的数值模拟是合理的。  相似文献   

2.
神经元网络用于PCDD定量构效关系的研究   总被引:2,自引:0,他引:2  
 研究了不同PCDD(全名Polychlorinateddioxin)同系物分子结构的表达及特征参数的选择,应用神经元网络方法对其分子结构与色谱保留值进行了关联。对49种PCDD同系物在DWS往上不同温度下保留时间进行了预测,结果95%以上的数据点相对误差小于10%,而80%以上的数据点相对误差小于5%。  相似文献   

3.
利用自制小型加压固定床气化炉研究气化剂为混合气的煤焦气化。混合气为含CO2、CO、H2和水蒸气的气体,它是模拟水煤浆气化炉出炉煤气成分在实验室制得的。实验考察气化温度、气化剂流速、混合气气体成分对煤焦气化的影响。实验发现,煤焦气化温度越高,气化剂流速越大,煤焦气化反应速度越快;H2、CO对煤焦气化有阻滞作用。  相似文献   

4.
用α-Al2O3研究比热测试与MDSC条件的相关性   总被引:1,自引:1,他引:0  
通过α-Al2O3的比热测试,研究了调制式差示扫描量热法(MDSC)测量比热(Cp)与温度(T)、线性升温速率(β)、温度调制振幅(AT)和调制周期(ρ)的相关性,并对测试误差进行校正.实验结果表明:Cp随T提高和ρ延长而增大;但β和AT对Cp影响不大;ρ=30 s时实测值(Cpms)与文献值(Csptd)的相对误差(Erms)最小,在温度为100~200℃范围小于3%;导出了对Cpms进行修正的多项式校正参数,在ρ为20~50 s、温度为100~200℃范围,修正后的比热(Cpmd)与文献值的相对误差(Ermd)小于1.5%.  相似文献   

5.
12兆瓦热电气多联产装置的开发   总被引:8,自引:1,他引:8  
介绍了为解决某钢铁企业的中热值煤气,蒸汽和电的短缺而开发的一台12MW的热电气多联产装置,在该系统中,把一台流化床气化炉和一台75t/h循环流化床锅炉结合在一起,从而实现煤气和蒸汽联产,在详细介绍了该装置的设计思想和结构特点的同时,用所建的热电气多联产模型对该装置包括煤气产量,煤气成分,煤气热值和系统运行温度等在内的性能参数进行了预测。  相似文献   

6.
研制了一套新型压力-温度-体积(PVT)性质测试系统.该系统由自行开发的测控软件实时测控,温度测量精度可达±10mK,压力测量系统最大不确定度为±1.2KPa.利用新的测试系统对294~351K温度区间的Hydrofluorocarbons(HFC)-245fa饱和蒸气压进行了研究.实验结果表明,HFC-245fa的测量值与公认文献值的平均偏差小于0.03%,最大偏差小于0.484%,结果与文献值吻合较好.  相似文献   

7.
水煤浆气化炉的数学模拟   总被引:4,自引:0,他引:4  
本文以水煤 浆气化炉气化过程的三区模型为基础,提出了计算气化炉出口煤气组成的混合模型,计算值与工厂测定值吻合良好。以A、M、N三种不同组成的煤为例,预测了煤种、气化压力、氧碳比、水煤浆浓度、热损失等因素对气化结果的影响。模拟结果表明,气化炉热损失显著影响煤气出口温度与级,适宜的氧碳比约为0.88左右,适宜的水煤浆浓度约为65%。  相似文献   

8.
聚光太阳能加热昭通褐煤的气化试验研究   总被引:1,自引:0,他引:1  
以云南昭通褐煤为原料,在聚光太阳能气化炉内,分别对昭通褐煤热解、气化过程中热解温度、气化温度及蒸汽流量等工艺参数对产品煤气成分的影响规律进行了试验研究。结果表明:随热解温度升高,煤气中CO2含量逐渐减少,H2含量增加;在800℃以前CO和CH4含量随着温度的升高而增加,当温度高于800℃后其含量随温度的升高而降低。在蒸汽流量一定的条件下,随气化温度升高,煤气中CO2、H2的含量下降,CO含量上升;在一定的气化温度下,随蒸汽流量的增加,煤气中CO2、H2含量增加,CO含量下降。同时根据热解产物量,分别对热解煤气产率、热解效率、热解强度等进行了计算,并通过能量收支平衡计算,得出太阳能的转化率为38.24%。  相似文献   

9.
间接原子吸收光谱法测定胱氨酸   总被引:1,自引:0,他引:1  
根据胱氨酸和碘酸银中的银生成的配合物,在谷氨酸和甘氨酸存在时用间接原子吸收光谱法测定了胱氨酸。研究了pH值、反应时间、试剂用量及加入试剂顺序的影响。对合成样品的分析表明,相对误差小于3%。  相似文献   

10.
木屑在鼓泡流化床和循环流化床中气化特性的对比研究   总被引:3,自引:0,他引:3  
对木屑在内径分别为0.3m×0.3m的鼓泡流化床气化炉(BFBG)和内径0.4m的循环流化床气化炉(CFBG)中的气化特征进行了对比,重点考察了当量比对生物质气化特性的影响。实验结果表明,在相同当量比下,由于CFBG操作气速明显高于BFBG,床内强烈的气固传热传质,使得CFBG可以获得较高的热解速率,同时可以使 CFBG在较高温度下运行。较高的运行温度不仅有利于二次裂解气化反应,使可燃气体质量明显好于BFBG,同时也减少了燃气中焦油的量。在较低气化当量比下(ER≤0.28),CFBG比BFBG可以获得更高的气体产率、碳转化率和气体效率;在较高当量比下,(ER>0.28),CFBG和BFBG的气体产率、碳转化率和气体效率则相差不大。  相似文献   

11.
An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.  相似文献   

12.
An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6ag and imidazo[1,5-a]quinoxalines 7ah by the reaction of 2-imidazolyl anilines 4ac with aryl aldehydes 5ak under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4ab was found to be instrumental for the success of the reaction.  相似文献   

13.
The Diels-Alder reactivity of 1,2-heteroborines (H4C4B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.  相似文献   

14.
A variety of N-aryl and N-alkyl carbazolones were conveniently achieved in good to high yields via Pd2(dba)3-mediated intramolecular coupling of N-substituted α-iodo enaminones under microwave irradiation. The Pd(0)-catalyzed cyclization was found to proceed favorably with the more electron-deficient phenyl ring during the reactions involving unsymmetrical N,N-diaryl α-iodo enaminones. This unique property enables the construction of carbazolone skeleton containing nitro substituted benzenoid ring.  相似文献   

15.
Both substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles have been synthesized by the 3+2 intramolecular dipolar cycloaddition of nitrilimines to alkynes. This cyclization has been extended to more versatile 3-bromo derivatives by the use of alkynylbromides as dipolarophiles.  相似文献   

16.
An efficient and benign method for the preparation of aminomethyl-substituted fullerenes has been developed. The process, involving catalyst free, visible-light irradiation of 10% EtOH-toluene solutions containing fullerene C60 and N-trimethylsilylmethyl-substituted amines by using a 20 W compact fluorescent lamp, leads to formation of aminomethyl-substituted fullerene adducts in a highly efficient manner. The photoaddition reaction takes place via a pathway initiated by visible light absorption by C60, followed by SET from the amine to the triplet excited state of C60. Ethanol-promoted desilylation of the resulting a minimum radical then generates the corresponding α-amino radical which couples with the C60 radical anion to form the anion precursor of the fullerene adducts. The new approach using visible-light takes place under mild conditions and it does not require the use of photocatalysts. Thus, the method developed in this effort could broadens the range of functionalized fullerene derivatives that can be readily prepared.  相似文献   

17.
The reactions of various nitrones with indolyl- and pyrrolylacrylates proceeds regioselectively with high diastereoselectivity in the case of aldonitrones, and represents an effective method for obtaining new indolyl- and pyrrolyl-substituted isoxazolidine carboxylates stabilized by weak (CH?O) and moderate (NH?N) strength intramolecular hydrogen bonding. The resulting cycloadducts exhibit promising in vitro anti-influenza activities.  相似文献   

18.
A transition metal-free method for the direct amination of benzoxazoles using formamides as nitrogen sources is reported, which was mediated by an inexpensive and environmentally friendly tetrabutylammonium iodide/tert-butyl hydroperoxide system and gave the 2-aminobenzoxazole derivatives with moderate to good yields.  相似文献   

19.
Multifunctionalized 1,2,3,4-tetrahydropyridines are concisely synthesized in good yields via l-proline-catalyzed or l-proline/FeCl3-cocatalyzed one-pot multicomponent reactions (MCRs). The MCRs involve a domino hydroamination/prins reaction/Mannich-type reaction/intramolecular dehydration-cyclization process. The molecular structure of 5baa, one of multifunctionalized 1,2,3,4-tetrahydropyridines, was confirmed by single-crystal X-ray diffraction.  相似文献   

20.
An efficient four-component reaction was developed to take advantage of the reactivity of the 2-aminothiophene-3-carbonitrile functionality, which is obtained during the classical three-component Gewald reaction. Various α-methylene bearing ketones were reacted with malononitrile, elemental sulfur, and aryl/heteroarylnitrile derivatives in t-BuOH/NaOH to afford 2-arylthieno[2,3-d]pyrimidin-4-amines in high yields. Preliminary studies revealed the photophysical properties of the products and their potential for use as metal sensors.  相似文献   

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