隔河岩工程水垫式消能护坦板设计

本文根据隔河岩工程的泄水方式及该工程水垫式消能消力池的流态,对该工程消力池的护照板的抗浮稳定进行计算,详细介绍了在护坦板抗浮稳定计算中各项作用力的拟定及护坦板的结构设计。     

甲烷/空气射流燃烧中氮氧化物生成模型的研究

With the development of reaction kinetics and transfer science, the modeling of NOx formation plays more and more important roles in the protection of environment and the design of combustion reactors; in this case,turbulence-chemistry model and NOx formation model are the two most important aspects. For thermal NOx mechanism, this article studied the CH4/air system and applied a set of latest NO formation rate constants published at the Leed University which replaced the original model code in FLUENT to increase its precision on prediction of NO concentration. The realizable k-ε model, Reynold Stress model and standard k-ε model were also investigated to predict the turbulent combustion reaction, which indicated that the simulation results of velocities, temperatures and concentrations of combustion productions by the standard k-ε model were in good accordance with the experimental data. With the application of the simulation results to the experimental data to fit some important kinetic parameters in the equation of O atom model and revision of the equation later, this article obtained a new NO formation rate model. It has been proved that the prediction of the developed model coincides well with the measurements.     

关于加快三峡工程建设的建议

三峡工程初步设计用第三期围堰挡水发电，使砼的年施工强度到达４００万ｍ＾３，考虑不均匀系数，施工强度达４５０－５００万ｍ＾３／年，远远超过伊太普工程的最高记录。为减少发电前大坝砼施工强度，采用大坝分期加高，优化大坝体型，减化施工措施和管理措施使三峡工程前提发挥效益。     

苯乙烯精馏技术中的问题及解决途径

苯乙烯精馏系统的关键是乙苯/苯乙烯精馏塔.本文结合实际生产装置,详细介绍了某生产装置苯乙烯精馏塔的设计情况和运行结果、遇到的问题及其解决方案,并将整改结果和原设计进行了对比.整改后,塔顶苯乙烯含量低于1%,最终产品中乙苯含量低于8×10-4,塔釜苯乙烯含量99.7%～99.9%,完全满足设计分离要求.     

Study on NO_x Formation in CH_4/Air Jet Combustion

1 INTRODUCTION The nitrogen oxides formed in combustion sys- tems is a significant source of environmental pollution. Nitrogen oxides consist of nitric oxide (NO), nitrogen dioxide (NO2), and nitrous oxide (N2O). NO and NO2 are collectively referred to NOx[1]. In laminar flames, and at the molecular level within turbulent flames, the formation of NOx can be attributed to three distinct chemical kinetic processes. The NOx formed by these three processes is described as thermal NOx, …     

竖井SVE修复有机污染土壤的数值模拟分析

采用Galerkin三角形有限单元法对复合地表边界的竖井土壤气相抽提（SVE）稳态流动问题进行了数值模拟分析，模拟结果显示：气相压力沿径向梯度迅速下降，抽提流量与土壤通透系数及真空度呈现高度相关的正比例关系，且地表隔绝覆盖层对流场影响很大.通过与野外实测真空度数据的对比验证，表明该二维轴径向流动模型能较好应用于现场条件，明显优于一维模型.再采用一个稳定的交替方向有限差分（ADI）解出传质微分方程，从而实现多维情况下竖井SVE修复的完整模拟过程.4组不同条件下为期60d的SVE修复过程的计算机模拟显示，土壤通透系数是决定修复效果的关键因素.在流场及传质方面建立的数值模拟分析对SVE的工程设计及预测可提供初步指导.     

磨煤机锤头的改革

在煤粉锅炉中,磨煤机是锅炉制粉系统中的主要设备。我厂现使用的锅炉中,有一台是在六十年代进口的罗马尼亚煤粉锅炉,磨煤机是采用二台竖井锤击式磨煤机。每台磨煤机的铭牌出力为5t/h,电机功率为55kW,磨煤机转速为980转/分。转子部分由轴、锤柄、锤头组成。每台安装锤头36个,每个锤头重7.9kg(图1)。由于磨煤机锤头存在着耐磨性能差,使用周期短,锤头加工困难,锤头的连接结构不便于拆装,更换锤头的施工时间     

土壤气相抽提过程非水相液体与气相的传质动力学研究

The mass transfer between non-aqueous phase liquid(NAPL) phase and soil gas phase in soil vapor extraction(SVE) process has been investigated by one-dimensional venting experiments. During quasi-steady volatilization of three single-component NAPLs in a sandy soil, constant initial lumped mass transfer coefficient (λgN,0) canbe obtained if the relative saturation (ξ) between NAPL phase and gas phase is higher than a critical value (ξc), andthe lumped mass transfer coefficient decreases with ξ when ξ＜ξc. It is also shown that the lumped mass transfercoefficient can be increased by blending porous micro- particles into the sandy soil because of the increasing of theinterfacial area.     

氯硅烷中甲基二氯硅烷的转化反应工艺 急

为了除去多晶硅原料中主要含碳杂质甲基二氯硅烷，通过催化反应将其转化为高沸点物质甲基三氯硅烷。采用浸渍法制备了Pd/Al2O3催化剂，采用X射线荧光光谱（XRF）、X射线粉末衍射（XRD）、N2吸附脱附（BET）、光电子能谱仪（XPS）、H2-脉冲化学吸附等分析手段对催化剂物化性质进行表征。在氯源物质为四氯化碳条件下，利用固定床反应器，对比了制备的Pd/Al2O3催化剂与树脂A催化剂和AlCl3/ Al2O3催化剂的催化效果,考察了Pd/Al2O3催化条件下，反应温度、反应物配比、反应空速及催化剂稳定性对甲基二氯硅烷转化率的影响，得到了最佳工艺条件。Pd/Al2O3催化剂相比于树脂A催化剂和AlCl3/ Al2O3催化剂，Pd/Al2O3催化剂具有更好的催化效果；在反应温度为140℃、n(甲基二氯硅烷):n(四氯化碳)=3:1、反应液时空速为5.0h-1时，甲基二氯硅烷转化率最高可以达到69.76%。     

三甲苯精馏分离的节能研究

以三甲苯精密精馏过程为实施案例,对多塔分离过程提出了热集成节能工艺。结合PRO/II软件对三甲苯分离三塔流程进行了模拟计算和节能优化,所得模拟结果与工业试验数据吻合良好。针对原有常压工艺难以实现热集成和能耗较高的运行现状,采用差压技术有效地实现了精馏流程的热集成。通过模拟计算得到了热集成的压强操作条件,并与原有常压工艺相比较,在不降低产品质量和收率的前提下,节能超过35%以上。