Multi-effect distillation system for seawater desalination driven by tidal energy and low grade energy

A multi-effect distillation technology for seawater desalination driven by tidal energy and low grade energy is presented.In the system,tidal energy is utilized to supply power instead of coventional electric pumps during the operation,resulting in the decrease of dependence on steady electric power supply and a reduction in the running costs.According to the technological principle,a testing unit is designed and built.The effects of the feed seawater temperature and the heat source temperature on the unit performance are tested and analyzed.The experimental results show that the fresh water output is 27 kg/h when the heating water temperature is 65 ℃ and the absolute pressure is 25 kPa.The experimental and theoretical analysis results indicate that the appropriate heating water temperature is a key factor in ensuring the steady operation of the system.

Chemical dehydration coupling multi-effect evaporation to treat waste sulfuric acid in titanium dioxide production process

In order to concentrate the diluted sulfuric acid from the titanium dioxide(TiO2)production of sulphate process,a new concentration process was proposed by coupling chemical dehydration and multi-effect evaporation.The ferrous sulfate monohydrate(FeSO4·H2O),as the dehydrant,was added to the diluted sulfuric acid to form ferrous sulfate heptahydrate(FeSO4·7H2O)according to the H2SO4-FeSO4-H2O phase diagrams,which partially removes the water.This process was named as Chemical Dehydration Process.The residual water was further removed by two-effect evaporation and finally 70 wt%sulfuric acid was obtained.The FeSO4·H2O can be regenerated through drying and dehydration of FeSO4·7H2O.The results show that FeSO4·H2O is the most suitable dehydrant,the optimal reaction time of chemical dehydration process is 30 min,and low temperature is favorable for the dehydration reaction.45.17%of the entire removed water can be removed by chemical dehydration from the diluted sulfuric acid.This chemical dehydration process is also energy efficient with 24.76%saving compared with the direct evaporation process.Furthermore,51.21%of the FeSO4 dissolved originally in the diluted sulfuric acid are precipitated out during the chemical dehydration,which greatly reduces the solid precipitation and effectively alleviates the scaling in the subsequent multi-effect evaporation process.

Selecting Suitable Heat Source in Refinery for Multi-effect Distillation Based on Grey System Theory

For dealing with high-salinity wastewater in the refinery, the high cost of driving heat source is the disadvantage of multi-effect distillation (MED) so it is of great importance to evaluate the performance of low-temperature heat source for conducting MED and select the optimal temperature for it. Both the MED and the low-temperature heat sources studied in this paper were from a typical refinery located in northwestern China. Besides, a new methodology to evaluate heat sources as the optimal candidate was proposed for MED based on the grey system theory. Five process units, which included 18 fluids of the refinery, were named as the evaluation projects. Three factors, which included safety effects, total costs and characteristics of low-temperature heat sources were determined as the evaluation indexes, the values of which were established through the analyses. The results obtained through the grey correlation analyses have revealed that the grey correlation degrees of these units were 0.661(AVDU), 0.732 (#1 FCCU), 0.618 (#2 FCCU), 0.535 (#1 DCU), and 0.572 (#2 DCU), respectively. Thus, the optimal heat source was provided from #1 FCCU. Through further analyses of the fluids from #1 FCCU, the grey correlation degrees of the fluids were 0.597 (oil and gas at top of tower), 0.714 (recycle oil and gas), and 0.512 (diesel), respectively. Thus, the optimal heat source was the oil and gas recycle stream.

Study on Multi-effect Time Parameters of Ergonomic Validity Index in Low-carbon Residential Kitchen

In the study on functional low-carbon ergonomic validity in buildings,ergonomic validity is different from resource validity which is easy for quantitative analysis. To eliminate the complexity and uncertainty impacts of human factors on quantitative study,it proposes a method of building a parameter of ergonomic validity—multi-effect time by using cardiotachometer to record heart rate change,being used to evaluate the functional low-carbon ergonomic validity targeting at the ontological characteristics of kitchen. This method is used to determine the physical consumption intensity( multi-effect) through heart rate incremental relation based on the principles of physiology and ergonomics,and to confirm the ergonomic validity of environmental factors by the time to complete standard work as well as multi-effect quantitative analysis. The test results show that,under the kitchen operating conditions,the multi-effect( ME) can properly reflect the real-time status of the operator and is easily operated; the parameters obtained are not significantly related to the physiological status of the operator,and multi-effect time( MT) is sensitive to the physical consumption brought about to the operator due to kitchen environmental factors; thus,it can be taken as an objective index,which is simple and easy to operate in residential kitchen functional low-carbon evaluation.

Simulation of Countercurrent Multi-Effect Drying System

The paper bulids a countercurrent multi-effect drying process model which can be expressed as a linear programming(LP) problem with the minimum total energy consumption as target function. Based on the model it can be conventient to solve the heat load , degree of drying and other drying parameters of each effect. And it realizes the mathematical simulation an analysis of multi-effect drying process. Such process not only reuses the secondary steam but also utilizes the high energy grade. Drying silica sand using 1-effect drying to 5-effect drying is presented as an example. The energy consumption and energy saving rate are compared by using co-current multi-effect drying and countercurrent multi-effect drying. As a summary, the countercurrent multi-effect drying is better than co-current drying. Considered the equipment investment and energy conservation, the study also concluded that the countercurrent 4-effect drying is the optimum selection, and it can save 57.6% energy compared to countercurrent 1-effect drying.

Multi-effects and Mechanism of Broad Beau M_1 Root-tip Cells Implanted by Low Energy N^+ Beam

Broad beans were divided into six groups and implanted with N+ beam of 30 KeV, 8 × 1016/cm2 per time for various radiating times respectively. Besides the statistics of its vigor of germination, the M1 root-tip cells of these broad beans were systematically analyzed on their changes in mitotic percentage, morphology and behavior of chromosomes, along with the structure o f cytoskeletons, including microtubule and intermediate filament. Based on all results of these studies, our opinions have been expressed in the report on the mechanism of low-energy N+ beams effecting on higher dicotyledons such as broad beau.

分子蒸馏及其在石油化工领域中的应用

分子蒸馏作为一种低碳、环保的新兴分离技术,在高沸点、热敏性物质的分离过程中展现出独特优势,国内外正处于开发利用的活跃期。文中系统介绍了分子蒸馏技术的分离原理、分离过程、影响因素等,并对分子蒸馏自身的优缺点、不同蒸馏设备之间的优缺点进行了总结对比,重点探讨了其在油品分离、油品分析、废油品回收等石油化工领域的应用。指出现阶段对分子蒸馏技术的基础理论研究不足,尤其是在反应过程的流体力学、传质传热数学仿真模型建立方面,并对扩大工业实际应用规模提出了建议。

TVC在MED海水淡化装置中的作用和性能分析

建立了蒸汽热力压缩器(thermal vapor compressor,TVC)和多效蒸发(multi-effect distillation,MED)海水淡化装置热力过程数学模型,计算分析了TVC对MED海水淡化装置性能的影响,讨论了对于一定设计条件下的海水淡化装置,蒸发器效数,TVC引射蒸汽、工作蒸汽及抽汽位置和装置的造水比、蒸发器传热面积、喷射系数的关系。结果表明:蒸发器效数、TVC吸入蒸汽温度的增加都会升高造水比;根据造水比和蒸发器传热面积,适当设置TVC在多效蒸发海水淡化装置中的抽汽位置,海水淡化装置的能效可以有很大的提高。

C10重芳烃二乙苯的分离研究

本文以C10重芳烃为原料,先采用精馏的方法获得间二乙苯、对二乙苯的富液,然后采用萃取精馏的方法,选择一种有效的萃取剂,将间二乙苯和对二乙苯的分离系数增大,以提高分离效率,减少能耗,获得较高的纯度和收率。

平流双效精馏过程的研究

本文对平流双效精馏过程进行了详细地研究，建立了最优化设计的数学模型并编制了通用计算机最优化设计程序，用实例对所建立的数学模型及优化设计方法进行了考核计算，发现平流双效精馏节能效果显著，具有很高的应用价值。

Case Studies of Heat Integration of Evaporation Systems

In this paper, through two case studies, evaporation systems are considered in the context of overall process, and then are optimized to obtain energy-saving effect. The possible evaporation schemes are given when integrated with the background process and how to optimize the evaporator is shown. From the case studies, it can be seen that sometimes incomplete integration and heat pump evaporation are better than complete integration so should be considered as candidate retrofit schemes.

Multi-effect anthraquinone-based polyimide enclosed SnO_(2)/reduced graphene oxide composite as high-performance anode for lithium-ion battery

The cycling stability of SnO_(2)anode as lithium-ion battery is poor due to volume expansion.Polyimide coatings can effectively confine the expansion of SnO_(2).However,linear polyimides are easily dissolved in ester electrolytes and their carbonyls is not fully utilized during charging/discharging process.Herein,the SnO_(2)enclosed with anthraquinone-based polyimide/reduced graphene oxide composite was prepared by self-assembly.Carbonyls from the anthraquinone unit provide fully available active sites to react with Li^(+),improving the utilization of carbonyl in the polyimide.More exposed carbonyl active sites promote the conversion of Sn to SnO_(2)with electrode gradual activation,leading to an increase in reversible capacity during the charge/discharge cycle.In addition,the introduction of reduced graphene oxide cannot only improve the stability of polyimide in the electrolyte,but also build fast ion and electron transport channels for composite electrodes.Due to the multiple effects of anthraquinone-based polyimide and the synergistic effect of reducing graphene oxide,the composite anode exhibits a maximum reversible capacity of 1266 mAh·g^(−1) at 0.25 A·g^(−1),and maintains an excellent specific capacity of 983 mAh·g^(−1) after 200 cycles.This work provides a new strategy for the synergistic modification of SnO_(2).

Screening the emission sources of volatile organic compounds （VOCs） in China by multi-effects evaluation

Volatile organic compounds （VOCs） play important roles in the atmosphere via three main pathways： photochemical ozone formation, secondary organic aerosol production, and direct toxicity to humans. Fewstudies have integrated these effect, s to prioritize control measures for VOC.s sources. In this study,we developed a multi-effects evaluation methodology based on updated emission inventories and source profiles, by combining the ozone formation potential （OFP）, secondary organic aerosol potential （SOAP）, and VOC toxicity data. We derived species-specific emission inventories for 152 sources. The OFPs, SOAPs, and toxicity of each source were estimated, the contribution and sharing of source to each of these adverse effects were calculated. Weightings were given to the three adverse effects by expert scoring, and then the integrated effect was determined. Taking 2012 as the base year,solvent use and industrial process were found to be the most important anthropogenic sources, accounting for 24.2% and 23.1% of the integrated effect, respectively, followed by biomass burning, transportation, and fossil fuel combustion, each had a similar contribution ranging from 16.7% to 18.6%. The top five industrial sources, including plastic products, rubber products, chemical fiberproducts, the chemical industry, and oil refining, accounted for nearly 70.0% of industrial emissions. Beijing, Chongqing, Shanghai, Jiangsu, and Guangdong were the five provinces contributing the largest integrated effects. For the VOC species from emissions showed the largest contributions were styrene, toluene, ethylene, benzene, and m/p-xylene.

Crevice Corrosion of Several Supper Stainless Steels in the Simulated LT-MED Environment

Susceptibility and morphological characteristics of crevice corrosion for SS316, SS904L, SS254sMo and SS2507 in thesimulated low-temperature multi-effect distillation environment were investigated by cyclic polarization test, scanningelectron microscope and laser microscope. The results show that the crevice corrosion resistance of four kinds of stainlesssteel is ranked as SS254sMo ≈ SS2507 〉 SS316 〉 SS904L. There are ＂cover＂ structures over the edge of active crevicecorrosion regions of SS904L, SS254sMo and SS2507, but SS316 is an exception. Galvanic corrosion characteristicsappeared in the crevice of duplex supper stainless steel SS2507.