采用BETHSY自然循环实验数据对CATHARE2 V1.5qR6程序的评价

采用BETHSY自然循环实验数据对CATHARE2 V1.5qR6进行了评价.结果表明CATHRE2V1.5程序能较好地预测试验装置单相自然循环条件下的热工水力现象,对单相自然循环向两相自然循环的转变以及两相自然循环向回流冷凝运行方式的转变发生时的一回路水装量预测也比较准确,但对于两相自然循环及回流冷凝运行方式下系统的一些主要热工水力参数预测欠佳.评价结果表明,与许多国际性大型热工水力分析程序一样,CATHARE2V1.5qR6程序对剧烈两相流动的预测能力仍有待改进和完善.     

Alginate–antacid combinations: raft formation and gastric retention studies

Background: Alginate-based gastroesophageal reflux disease treatments have been used extensively and fall into two main categories. Those containing alginate as the principle active agent and those containing alginate in combination with a significant amount of antacid. Method: The effectiveness of the raft formed by a new alginate/antacid suspension (Gaviscon Double Action Liquid, GDAL), in which calcium carbonate was the main antacid ingredient, was compared with those of existing alginate/antacid suspensions. Result: GDAL had similar raft strength and improved raft resilience than Gaviscon Liquid (GL), and both were significantly greater than five other products tested. Gastric retention of GDAL was similar to that of GL. Conclusion: the in vitro and in vivo performance is maintained in the new GDAL formulation even with higher antacid levels and the product is as good as, or better than, previous formulations.     

Effect of External Recycle and Double-Pass Barrier Location on Membrane Extraction in Cross-Flow Modules

Abstract

The dispersion free membrane extraction through a cross-flow rectangular membrane module with arbitrary location of an impermeable plate placed for double-pass and external-recycle operations in raffinate phase, has been investigated. Theoretical treatment was analogous to the heat transfer in heat exchangers for the mass transfer in mass exchangers. An experiment was carried out in a cross-flow conduit of stainless steel inserted with a membrane sheet made of microporous polypropylene to extract acetic acid from aqueous solution by methyl iso-butyl ketone. Theoretical predictions are in agreement with the experimental results. Considerable improvement in mass-transfer performance is obtainable if the width of the first-pass subchannel, ΔB decreases, as well as the width of the second-pass subchannel, (1?Δ)B increases. The mass-transfer rate increases also when the reflux ratio increases. Based on the economic point of view, the suitable value of Δ (B is the width of a membrane sheet) may be 0.2.     

简捷水热法制备氟化石墨烯及其表征

氟化石墨烯是一种石墨烯衍生物,在润滑材料、电子器件等领域具有广阔的应用前景。采用回流搅拌并水热还原的方法制备氟化石墨烯,并在不加HF的情况下以同样的方式制备了水热还原的还原氧化石墨烯(rGO)。采用傅里叶变换红外光谱(FTIR)、X射线衍射(XRD)、拉曼光谱(Raman)、X射线光电子能谱(XPS)、透射电镜(TEM)等对样品进行形貌观测和表征。FTIR的结果表明氟化产物中含有C-F键和部分未完全还原的含氧基团;由XRD谱可以看出,产物晶型较差,其层间距和原料的性质有关;Raman谱证实了石墨烯的基本结构依然存在,但也存在大量缺陷,并且rGO比FGS的规整度略高;XPS谱表明样品表面有氟元素的存在,意味着FGS制备成功;TEM结果显示该样品为单层和少层。该方法操作简单、原料廉价易得、工艺要求不高,适用于批量生产氟化石墨烯。     

沉降罐加气浮技术处理含聚污水的现场试验研究

为了提高油田含聚污水的处理效果,对污水站已建的沉降罐进行了改造。通过在自然沉降罐前增加管式反应器和在内部设置穿孔布气管,进行管式反应器单独气浮、穿孔布气管单独气浮及管式反应器和穿孔布气管同时气浮3种方式处理含油污水的现场试验。试验结果表明,与不加气浮自然沉降罐相比,3种气浮方式油的去除率都提高23%以上,SS去除率都提高了19%以上,并确定了合理的回流量。     

异丁醇生产中精馏新型塔控制方案

提出了异丁醇生产中精馏塔的新型控制方案,该方案将精馏塔控制系统分为3个子系统,即入料控制子系统、精馏段控制子系统和提馏段控制子系统。精馏段和提馏段的控制通过调节回流量的大小(即控制回流比的数值)来完成相应的工艺控制任务,采用KMM可编程控制器进行控制,通过MATLAB仿真,对所选择的控制方案进行了模拟仿真运行,结果表明,方案正确、可行,完全可以用于工业生产中。     

甲醇精馏装置运行总结

介绍和分析了黑龙江北大荒股份有限公司浩良河化肥分公司100 kt/a甲醇装置投运以来工艺和设计上存的缺陷,生产过程中出现的问题,以及针对问题所采取的措施及改进.     

MTO级甲醇单塔精馏工艺能耗分析

本文主要研究了国内2008年投产的某大型煤制烯烃项目整个工艺流程中其中一小部分工艺的节能降耗,即粗甲醇精制MTO级甲醇单塔精馏工段的能耗问题,在达到煤制烯烃工段所要求的MTO级甲醇指标的条件下,通过优化回流比、回流温度、馏出液温度等指标达到节能降耗的目的。     

三次样条函数拟合平衡曲线求最小回流比

本文采用三次样条函数拟合汽－液平衡曲线，求算板式精馏塔的最小回流比．该法快速准确，适用于各种物系．文中给出了电算程序框图和计算实例．     

Research on Dynamics Design for Active Sludge System

In order to describe the relationship between dynamic process and sludge-removing load in active sludge system, a new method for designing the volume of aeration tanks was put forward based on the Michaelis and Menten cquation. the influence of sludge returning was considered in the design. The result shows that the parameter of sludge reflux ratio plays a very important role in tbe design of active sludge systan. In some given conditions, there exists an optimum reflux ratio which can make the volume of aeration tank be the minimum.