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41.
两段式固定床富氧-水蒸气气化实验研究 总被引:2,自引:0,他引:2
两段式固定床富氧-水蒸气气化实验研究 《燃料化学学报》2011,39(8):595-599
以玉米芯颗粒为原料在两段式固定床气化装置上进行了气化实验,考察了当量比ER、富氧浓度OC和水蒸气配比S/B对气化温度、气化气组分、低位热值、气体产率、气化效率和碳转化率等参数的影响,并比较了两段式固定床与传统下吸式固定床的气化特性。实验结果表明,当量比为0.27时H2的体积分数、CO的体积分数和气化效率达到最大值;增加富氧浓度能优化气化效果,但富氧浓度大于90%后,燃气质量和气化效率均提高不大;增加S/B能提高H2的体积分数,但同时会降低CO的体积分数、气体热值、气化效率;当S/B为0.6时,氢气的体积分数达最高值33.3%,H2/CO比为1.32;相比于传统固定床,两段式固定床气化可明显提高气化温度、氢气的体积分数、碳转化率和气化效率,降低焦油含量。 相似文献
42.
针对“仓店一体化”模式下提供限时送达服务的新零售仓店,研究多拣货员、多客户、配送方式为带限时送达约束的路径优化分批配送情形下的订单拣选与配送集成调度问题。以最小化订单最大履行时间和配送成本为目标,构建了混合整数非线性规划模型,并设计两阶段启发式算法(H-2)进行求解,最后通过数值实验对算法进行验证与分析。数值实验结果表明,H-2具有较高的求解质量;相较于传统调度算法(TS)在效率提升、资源节约以及客户满意度提高方面具有更优的表现,进而为新零售仓店管理者提供决策支持。 相似文献
43.
流化床煤气化炉内脱硫的研究Ⅰ.台式流化床煤气化的炉内脱硫试验 总被引:1,自引:0,他引:1
采用台式流化床煤气化装置,研究了影响炉内脱硫效率的因素。炉内脱硫对高硫煤特别有效,脱硫效率可达90%以上。所采用的二种石灰石和一种白云石脱硫效率相近,按Ca/S比比较则白云石稍好些。虽然脱硫效率随Ca/S比增加而增加,但当Ca/S比达到3后几乎不再增加。存在一个最佳脱硫操作温度。在非焙烧区,脱硫率随压力增加而下降,而在焙烧区脱硫率和压力几乎无关。测定了脱硫剂脱硫前后的孔容积分布,发现脱硫之后1~30nm的孔容显著减少。 相似文献
44.
45.
A. Shapiro 《Journal of Optimization Theory and Applications》2006,128(1):221-243
In this paper, we discuss here-and-now type stochastic programs with equilibrium constraints. We give a general formulation
of such problems and study their basic properties such as measurability and continuity of the corresponding integrand functions.
We discuss also the consistency and rate of convergence of sample average approximations of such stochastic problems 相似文献
46.
利用递变冲击阻抗材料叠合而成的组合飞片,在二级轻气炮上对无氧铜进行了准等熵压缩性测量,加载时间约达1 μs。用激光速度干涉仪连续记录了不同厚度处无氧铜样品自由面速度随时间的变化过程,并通过拉格朗日波分析技术计算得到40 GPa下的准等熵的应力-应变曲线。结果表明:在低应力区,无氧铜的准等熵压缩线位于冲击绝热线之上;到32 GPa以上,准等熵压缩线才回落到冲击绝热线之下。这个现象与Barker、Chhabildas等对铝与钨的实测现象是一致的,它表明:在低应力区,材料的冲击强化效应与加载速率密切相关。 相似文献
47.
Parallel Newton two-stage iterative methods to solve nonlinear systems are studied. These algorithms are based on both the multisplitting technique and the two-stage iterative methods. Convergence properties of these methods are studied when the Jacobian matrix is either monotone or an H-matrix. Furthermore, in order to illustrate the performance of the algorithms studied, computational results about these methods on a distributed memory multiprocessor are discussed.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
48.
An experiment on gain enhancement in the long wavelength band erbium-doped fiber amplifier (L-band EDFA) is demonstrated using
dual forward pumping scheme in double-pass system. Compared to a single-stage single-pass scheme, the small signal gain for
1580 nm signal can be improved by 13.5 dB. However, a noise figure penalty of 2.9 dB was obtained due to the backward C-band
ASE from second stage and the already amplified signal from the first pass that extracting energy from the forward C-band
ASE. The maximum gain improvement of 13.7 dB was obtained at a signal wavelength of 1588 nm while signal and total pump powers
were fixed at -30 dBm and 92 mW, respectively. 相似文献
49.
Review of proton conductors for hydrogen separation 总被引:1,自引:0,他引:1
There is a global push to develop a range of hydrogen technologies for timely adoption of the hydrogen economy. This is critical in view of the depleting oil reserves and looming transport fuel shortage, global warming, and increasing pollution. Molecular hydrogen (H2) can be generated by a number of renewable and fossil-fuel-based resources. However, given the high cost of H2 generation by renewable energy at this stage, fossil or carbon fuels are likely to meet the short- to medium-term demand for hydrogen. In view of this, effective technologies are required for the separation of H2 from a gas feed (by-products of coal or bio-mass gasification plants, or gases from fossil fuel partial oxidation or reforming) consisting mainly of H2 and CO2 with small quantities of other gases such as CH4, CO, H2O, and traces of sulphur compounds. Several technologies are under development for hydrogen separation. One such technology is based on ion transport membranes, which conduct protons or both protons and electrons. Although these materials have been considered for other applications, such as gas sensors, fuel cells and water electrolysis, the interest in their use as gas separation membranes has developed only recently. In this paper, various classes of proton-conducting materials have been reviewed with specific emphasis on their potential use as H2 separation membranes in the industrial processes of coal gasification, natural gas reforming, methanol reforming and the water–gas shift (WGS) reaction. Key material requirements for their use in these applications have been discussed. 相似文献
50.
David N. Thompson Peter G. Shaw Jeffrey A. Lacey 《Applied biochemistry and biotechnology》2003,105(1-3):205-218
Silica and alkali metals in wheat straw limit its use for bioenergy and gasification. Slag deposits occur via the eutectic
melting of SiO2 with K2O, trapping chlorides at surfaces and causing corrosion. A minimum melting point of 950°C is desirable, corresponding to an
SiO2:K2O weight ratio of about 3:1. Mild chemical treatments were used to reduce Si, K, and Cl, while varying temperature, concentration,
% solids, and time. Dilute acid was more effective at removing K and Cl, while dilute alkali was more effective for Si. Reduction
of minerals in this manner may prove economical for increasing utilization of the straw for combustion or gasification. 相似文献