Shortcut Method of Design and Energy-Saving Analysis of Sargent Dividing Wall Column

The Sargent dividing wall column can implement four products separation sequences in one column based on Fully Thermally Coupled Distillation Column. The initial design parameters are required for the design optimization or dynamic control of the Sargent dividing wall column, and in order to make the rigorous simulation of the Sargent dividing wall column more conducive to convergence, a ten column model for complex Sargent column is established in this paper,and the shortcut design method of this model is proposed. The internal minimum vapor and liquid flow are obtained by the Underwood equations and the mass balance method and the V-min method. The separation for a 4-component shortcut mixture of pentane, hexane, heptane and octane was considered, while the initial values of design parameters and the ratio of vapor-liquid distribution of each column were calculated by using the shortcut design method of a ten column model. And by comparing the shortcut calculations with rigorous simulation results, the practicality and reliability of shortcut calculations were verified. The reason for energy saving was analyzed based on back-mixing. A virtual heat exchanger is proposed to make the Sargent dividing wall column more energy efficient.

Energy-saving Technology of Vent in Passive Solar Wall of Rural House of Severe Cold Region

This paper aims at solving the problems of low thermal collection rate,inconvenient maintenance,hindering indoor using during the application of passive solar technologies in rural houses in severe cold region.All these defects prevent the passive solar houses' further development. This paper chooses trombe wall,which has higher thermal efficiency of the passive solar house,as research object. The traditional vent is improved into a new type of ventilation device. This improvement overcomes the shortcoming,which traditional vent loses huge heat,and simplifies the construction of vent. Comparing with traditional trombe wall,the energy saving rate is 15. 69%.

Experimental and simulation of the reactive dividing wall column based on ethyl acetate synthesis

Reactive dividing wall column(RDWC) is a highly integrated unit which combines reaction distillation(RD) with dividing wall column separation technology into one shell, and it realized the chemical reaction and the separation of multiple product fractions simultaneously. In this paper, the reaction of esterification with acetic acid and ethanol to produce ethyl acetate was used as the research system, experiments and simulations of the RDWC were carried out. This system in the traditional process mostly used the homogeneous catalyst(e.g. sulfuric acid). However, in view of the corrosion of the equipment caused by the acidity of the catalyst, we used the heterogeneous catalysts – iron exchange resins – Amberlyst15 and proposed a novel catalyst loading method. Firstly,the reliability of the model of the simulation was verified by the experimental study on the change of liquid split ratio and reflux ratio. After that, the four-column model was established in Aspen Plus to analyze the effects of the amount of azeotropic agent, reflux ratio and acetic acid concentration. Finally, for a fair comparison, the economic analysis was conducted between traditional RD column and RDWC. The results showed that RDWC can save34.7% of total operating costs and 18.5% of TAC.

Reactive dividing-wall column for the co-production of ethyl acetate and n-butyl acetate

Reactive dividing-wall column(RDWC) technology plays a critical role in the energy saving and high efficiency of chemical process.In this article, the process of co-producing ethyl acetate(EA) and n-butyl acetate(BA) with RDWC was studied.BA was not only the product, but also acted as entrainer to remove the water generated by the two esterification reactions.Experiments and simulations of the co-production process were carried out.It was found that the experimental results were in good agreement with the simulation results.Two kinds of RDWC structures(RDWC-FC and RDWC-RS) were proposed, and the co-production process operating parameters of the two types of RDWC were optimized by Aspen Plus respectively.The optimal operating parameters of the RDWC-FC were determined as follows: 0.6 of the reflux ratio of aqueous phase(RR), 0.66 of the vapor split(R_V) and 0.51 of the liquid split(R_L).And the optimal operating parameters of the RDWC-RS were shown as follows: RR was 0.295 and R_V was 0.61.Furthermore, the energy saving analysis of the co-production process was based on the annual output of 10000 tons of EA, compared with the traditional reaction distillation(RD) to prepare EA and BA, the reboiler duty of the RDWC-FC column could save 20.4%, TAC saving 23.6%; RDWC-RS reboiler energy consumption could save 17.0%, TAC 22.2%.

ANALYSIS FOR THERMAL BEHAVIOR AND ENERGY SAVINGS OF A SEMI-DETACHED HOUSE WITH DIFFERENT INSULATION STRATEGIES IN A HOT SEMI-ARID CLIMATE

The purpose of this research is to assess thermal performance and energy saving of a residential building in the hot semi-arid climate of Marrakech(Morocco).The studied house is built as usual in Marrakech without any thermal insula-tion except for its external walls,facing East and West,which are double walls with a 5 cm air gap in between(“cavity wall”technique).The cavity wall effec-tive thermal conductivity was carefully calculated taking into account both radia-tion and convection heat transfers.Experimental results,obtained from winter and summer monitoring of the house,show well dampening of air temperature,thanks to its thermal inertia.However,this temperature remained outside the standard thermal comfort zone leading to large cooling/heating load.Simula-tion results indicate that the cavity wall contributes to an overall reduction of 13%and 5%of the house heating and cooling loads respectively.Moreover,the addition of XPS roof thermal insulation significantly enhances the heating and cooling energy savings to 26%and 40%respectively.

Analysis of Energy Saving Reconstruction of Existing Campus Dormitories in Chongqing——Taking Dormitory Six on Campus B of Chongqing University as An Example

At present,a large number of historic buildings on campus are lack of energy-saving measures from the design time,especially the dormitories. And the reconstruction mostly focuses on functional reorganization or furniture replacement. However,energy efficiency design has not been paid enough attention,which leads to the high building energy consumption and the harsh physical environment. Based on the analysis of climatic characteristics of Chongqing area,taking Dormitory Six on campus B of Chongqing University as an example,the reconstruction of rooms on the top floor and West end are focused to guarantee the equal benefits of the dormitory environment. Through the simulation analysis of the software, on the basis of energy saving reconstruction of common maintenance structure,this thesis discusses the energy saving reconstruction methods and strategies of the existing campus dormitories,which are more suitable for the existing campus dormitories in Chongqing area.

农作物秸秆低碳墙体材料研究现状

综述了近年来国内外关于农作物秸秆在建筑墙体材料中的应用及研究进展,从生产技术、制备工艺、配合比设计等方面出发,重点介绍了农作物秸秆低碳墙体材料的力学性能、保温隔热性能、阻燃性能等优良特性,并对农作物秸秆低碳墙体材料现阶段所存在的缺陷和不足给出了合理建议,对其未来发展方向及应用前景做出了展望。

夏热冬冷地区办公建筑节能改造设计研究

本文主要探究了夏热冬冷地区某办公建筑的节能改造设计方案。调查发现,该办公建筑一天之中8-18时能耗较高;一年之中夏季能耗最高,冬季次之;空调能耗在总能耗中的占比最大。基于实用性和经济性原则,选择建筑围护结构进行了节能设计,外墙方面使用EPS保温板,屋顶设计成种植屋面,外窗改造成真空玻璃窗和双层玻璃幕墙。结果表明,相比于原建筑,使用节能设计方案后外墙、屋顶和外窗的传热系数均有大幅度的降低,使得建筑保温隔热性能明显提升,达到了节能降耗的效果。

优化设计萃取隔板精馏塔分离苯-环己烯体系

苯和环己烯共沸物的高效节能分离是常见的工业难题,而EDWC(萃取隔板精馏塔)在共沸物的分离中具有重要的应用前景,目前公开的文献中鲜有关于EDWC工艺对苯和环己烯分离的报道。以氯化胆碱/乙酰丙酸摩尔比为1∶2作为萃取剂,探索EDWC技术在苯和环己烯分离中的应用,采用粒子群算法对该工艺进行优化设计。考虑到粒子群算法是一种随机优化算法,引入变异系数对算法的稳定性能进行评价。最后,引入年度总成本、二氧化碳排放量、[火用]损失3个定量指标从经济性、环境性和热力学性3个方面对EDWC工艺和传统的两塔萃取精馏工艺进行全面对比。结果表明:与传统的两塔萃取精馏工艺相比,EDWC工艺可减少19.15%的年度总成本、36.08%的二氧化碳排放量、19.99%的[火用]损失以及8.03%的萃取剂消耗量。EDWC工艺分离苯和环己烯混合物具有优异的分离效率和显著的节能优势。

基于DIALux的运营公路隧道墙面反射系数对照明节能的影响研究

为了量化分析墙面反射系数对运营公路隧道照明节能的实际效果、节能率与经济性的影响,本文基于DIALux照明计算软件对公路隧道全段照明环境进行仿真,模拟了9种不同反射系数(0.1~0.9)下的隧道内照明情况,结合20条实例隧道共180种工况进行模拟,研究墙面反射系数对隧道内路面照明效果的影响,通过降低照明配置得出节能率,并运用静态投资回收期进行经济性分析。

节能墙体隔热材料在住宅建筑设计中的研究

现今新型建筑节能墙体材料常运用于住宅建筑中,故本研究针对新型建筑节能材料特点,分析其在住宅建筑的应用,并对不同规模的墙体总厚度在不同室外环境温度下的能耗对比。试验结果表明,墙体总厚度在105mm条件下,当室外环境温度为40℃时,空调的降温能耗相差3.2℃,此时差值最大,空调降温能耗的降低趋势均减缓,建筑的节能效果明显降低。在室外环境为–30℃时,空调的取暖能耗相差为4.8℃,取暖能耗均呈现降低的趋势。由此可见,在外界环境高、低气温环境下均能获得较为显著的建筑节能效果,但墙体总厚度超过105mm时其实用价值不大。

城市更新项目中外墙保温技术应用

本文主要探讨了城市更新项目中老旧小区外墙保温技术的应用。通过分析老旧小区建筑外墙节能保温的现状,阐述了外墙保温技术的意义和重要性。本文从建筑外墙保温构造做法、工艺流程、施工中容易忽略的问题及保温施工通病及措施等四个方面,介绍了各种节能保温技术的具体应用方法和效果。最后,总结了城市更新项目中老旧小区外墙保温技术的发展趋势和未来发展方向。

既有建筑外墙外保温节能改造及经济效益分析

随着社会的发展,许多二十世纪八九十年代建造的房屋外墙结构保温隔热性能已经不足以满足当今需求,从而导致能耗过高、室内热环境恶化。为此,我国正在积极推进绿色发展,努力实现低碳、可持续的生产和生活方式。为节约资源能源,改善居住环境,有必要对旧有建筑墙体进行改造。结合济南市某节能改造项目,介绍了一种新型外墙外保温工艺,并对其经济效益进行了综合研究,结果表明,该工艺节能效果好,经济效益显著。

民用建筑节能检测中常用外墙保温隔热材料检测方法研究

为解决民用建筑能耗大的问题,本文结合某工程的实际情况,详细分析了民用建筑外墙保温隔热材料节能检测原理后,针对在检测过程中存在的问题,提出了相应的解决措施,其中涵盖了优化改善检测环境、创新升级检测设备以及做好取样工作等,旨在提升常用外墙保温隔热材料在民用建筑中的应用质量和效率,促进建筑行业的节能化发展,以期为相关人员提供参考和借鉴。

真空玻璃改造香港地区既有玻璃幕墙的热性能研究

为降低既有建筑的运行能耗,提出一种应用真空玻璃对香港地区高层建筑既有玻璃幕墙的节能改造方法,并通过户外实验测试对比研究了节能改造前后幕墙的热工性能和热舒适水平。结果表明,该节能改造方法可显著降低幕墙的内表面温度、内表面热流密度、太阳辐射透过率和太阳得热系数,并提高室内的热舒适水平。其中内表面热流密度平均降幅高达81.6%,太阳得热系数最大降幅可达83%,有利于降低建筑冷负荷。此方法适用于空调负荷需求大的城市,其分析结果将为在炎热气候地区开展高层建筑既有玻璃幕墙节能改造工作提供指导,并为实现“碳中和”目标助力。

树木墙冠距对独立式农宅节能率的影响研究

树木对建筑具有节能效应,但树木与农宅的空间关系对农宅能耗的影响规律尚需进一步挖掘。为充分发挥树木降温节能的生态效益,以浙江嘉兴独立式农宅为对象,应用数值模拟法获取90种不同空间位置关系所对应的农宅节能率,最后分析不同农宅朝向、不同树木方位与不同墙冠距对农宅节能率的综合影响规律。结果表明,以不同墙冠距对应的节能率变化范围为依据,当农宅为正南朝向时,可得出树木方位对应的节能率大小依次为:西侧≈东侧>东南侧≈西南侧>东北侧≈西北侧。对位于农宅东、西两侧的树木而言,可得出农宅朝向对应的节能率大小依次为:正南≈南偏西10°>南偏东20°>南偏东10°>南偏西20°。上述研究可为节能视角下的独立式农宅邻近绿化提供科学依据。

建筑外墙外保温系统节能施工技术探析

伴随当下社会的不断进步,科学技术的日益提高同样促使建筑行业迈入了一个崭新的台阶,这也就促使人们开始将目光转移到居住环境上来,尤其是房屋建筑方面的需求也越来越高。当前,与建筑物外保温有关的技术已引起社会各方的高度重视,它直接影响着人类是否能够获得一个更为舒适的居住环境。作者从建筑外墙外保温系统节能技术的概况入手,对外墙外保温系统的施工工艺进行了较为系统的讨论,希望可以为提高我国建筑外墙外保温工程的品质,同时也为相关研究提供一些借鉴。

光伏新能源技术在电气节能中的应用效果调研分析

为提升清洁能源的利用效率,并研究光伏新能源在电气节能中的应用效果。该文通过对多个光伏发电项目的应用进行调研和分析,并结合实际案例对不同光伏发电项目的应用效果进行评价。结果表明,在电气节能中应用光伏新能源技术具有安全性无污染、供电稳定、减少能源消耗等明显优势。说明在电气节能中应用光伏发电技术,能够有效提升清洁能源的利用效率。并且光伏发电系统的长期投资回报率明显优于传统发电系统。

高层建筑外墙保温施工技术及节能材料的应用研究

在土建建筑绿色节能设计与施工要求的前提下,高层建筑外墙面的保温施工,也要采取重量轻、强度高、采光好的墙体保温材料,从不同保温层材料的物理特性、施工工艺等角度出发,进行建筑外墙保温施工重要工序的规划设计。通过围绕高层建筑外墙保温、节能、环保等的建设需求,探讨不同类别建筑材料的结构构造、通风状况与保温效果,并设置建筑工程保温施工的执行流程,以满足现代建筑工程的保温、节能与降耗要求。

绿色建筑技术在建筑设计中的优化与结合研究

文章研究对比了传统建筑与应用外墙节能技术的建筑在能源利用和外墙材料性能方面的差异。实验数据显示,节能技术建筑在能源利用方面明显改善,在供暖和制冷方面能耗降低约15%~20%,夏季空调能耗减少约25%。在外墙材料性能方面,节能技术建筑的隔热和保温性能优于传统建筑,夏季温度降低2~3℃,冬季温度提高1~2℃。结果表明,外墙节能技术的应用能显著提升建筑的能效和室内舒适度。