Magnetic core-shell microparticles for oil removing with thermal driving regeneration property

Here, we report the construction of magnetic core-shell microparticles for oil removal with thermal driving regeneration property. Water-in-oil-in water (W/O/W) emulsions from microfluidics are used as templates to prepare core-shell microparticles with magnetic holed poly (ethoxylated trimethylolpropane triacrylate) (PETPTA) shells each containing a thermal-sensitive poly (N-Isopropylacrylamide) (PNIPAM) core. The microparticles could adsorb oil from water due to the special structure and be collected with a magnetic field. Then, the oil-filled microparticles would be regenerated by thermal stimulus, in which the inner PNIPAM microgels work as thermal-sensitive pistons to force out the adsorbed oil. At the same time, the adsorbed oil would be recycled by distillation. Furthermore, the adsorption capacity of the microparticles for oil keeps very stable after 1st cycle. The adsorption and regeneration performances of the microparticles are greatly affected by the size of the holes on the outer PETPTA shells, which could be precisely controlled by regulating the interfacial forces in W/O/W emulsion templates. The optimized core-shell microparticles show excellent oil adsorption and thermal driving regeneration performances nearly without secondary pollution, and would be a reliable green adsorption material for kinds of oil.

Effect of Thermal Regeneration on the Breakthrough Performance of Ceramsite Saturated with Methylene Blue

The regeneration of a spent packing is crucial with respect to the development of circular economy and abstemious society.Thus,the effects of regeneration temperature,resistant time,heating rate,and regeneration cycle on the breakthrough performance of methylene blue(MB)dye⁃exhausted ceramsite in a two⁃stage fixed⁃bed column were studied in this work.Results illustrate that the ceramsite exhibited excellent potential regeneration properties under the following optimal regeneration conditions:treatment temperature was 600°C,resistant time was 15 min,heating rate was 20℃/min,regeneration cycle was over 9 cycles,and the breakthrough time,saturation time,regeneration efficiency(RE),and regeneration loss rate(RLR)were 540 min,1020 min,64.61%,and 17.73%,respectively.The RE declined by 35.14%in over 1 cycle,while the RLR increased by 3.15 times in over 9 cycles.Besides,Thomas model was suitable to describe the two⁃stage fixed⁃bed column adsorption and thermal regeneration process with R2=0.978.In conclusion,a thorough understanding of the regeneration behavior of the two⁃stage fixed⁃bed column packed with ceramsite provides reference to obtain an effective and feasible regeneration approach,and it is beneficial for further application in water treatment.

Perturbation Solutions for Thermal Process of Honeycomb Regenerator

A parameter perturbation for the unsteady-state heat-transfer characteristics of honeycomb regenerator is presented. It is limited to the cases where the storage matrix has a small wall thickness so that no temperature variation in the matrix perpendicular to the flow direction is considered. Starting from a two-phase transient thermal model for the gas and storage matrix, an approximate solution for regenerator heat transfer process is derived using the multiple-scale method for the limiting case where the longitudinal heat conduction of solid matrix is far less than the convective heat transfer between the gas and the solid. The regenerator temperature profiles are expressed as Taylor series of the coefficient of solid heat conduction item in the model. The analytical validity is shown by comparing the perturbation solution with the experiment and the numerical solution. The results show that it is possible for the perturbation to improve the effectiveness and economics of thermal research on regenerators.

Jonzac Thermal Spring Water Reinforces Skin Barrier Function of Human Skin and Presents a Soothing and Regenerating Effect

The skin is a formidable physical and biological barrier which communicates continuously with the outside of the body. And the stratum corneum, the outermost layer of human epidermis, plays a central role in the interaction between the cutaneous tissue and the external environment. The horny layer, and more generally the whole skin layers, avoid the penetration of harmful exogenous agents, produce molecules named anti-microbial peptides which impact the composition of the cutaneous microbiota, regulate the internal corporal temperature, avoid the water loss from the inside of the body and constitute an incredible efficient anti-oxidant network. Nevertheless, nowadays, the skin is more and more solicited by the different elements of the cutaneous exposome, including atmospheric pollution and solar radiations, which can cause a dramatic acceleration of the skin ageing process. As a consequence, due to the multifunctional protective role of the skin, during the recent decade the cosmetic industry invested massively in the development of new raw materials and end-products (dermo-cosmetics) able to preserve an optimal state of the skin regarding the external environment. Based on their physical-chemical properties thermal spring waters, which are extremely rich in inorganics ions, are interesting and powerful candidates to be part, as integral component, of new efficient dermo-cosmetic formulations dedicated to protect the skin from the external stimuli. The aim of the present work was to investigate and characterize the activity of Jonzac thermal spring water on the skin. Using different models, we proved for the first time that Jonzac thermal spring water reinforces the barrier function of the skin by modulating the expression of key markers including filaggrin and human beta defensin 2 on ex vivo human skin. The ex vivo and in vivo hydration activity, by Raman spectroscopy and corneometry respectively, has been also demonstrated. We have also shown that Jonzac thermal spring water ameliorates significantly the cutaneous microrelief in vivo. To conclude, we characterize the soothing effect of Jonzac thermal spring water by the analysis of histamine release in Substance P treated skin explants and by measuring the redness of the skin following UV exposure of the skin in vivo. We observed that both parameters decreased following a preventive treatment of the skin with Jonzac thermal spring water. Taken together our results indicate that Jonzac thermal spring water is a promising and powerful dermo-cosmetic which can be used to preserve an optimal state of the cutaneous tissue.

Construction of Renewable Superhydrophobic Surfaces via Thermally Induced Phase Separation and Mechanical Peeling

We report a simple preparation method of a renewable superhydrophobic surface by thermally induced phase separation （TIPS） and mechanical peeling. Porous polyvinylidene fluoride （PVDF） membranes with hierarchical structures were prepared by a TIPS process under different cooling conditions, which were confirmed by scanning electron microscopy and mercury intrusion porosimetry. After peeling off the top layer, rough structures with hundreds of nanometers to several microns were obtained. A digital microscopy determines that the surface roughness of peeled PVDF membranes is much higher than that of the original PVDF membrane, which is important to obtain the superhydrophobicity. Water contact angle and sliding angle measurements demonstrate that the peeled membrane surfaces display super- hydrophobicity with a high contact angle （152°） and a low sliding angle （7.2°）. Moreover, the superhydrophobicity can be easily recovered for many times by a simple mechanical peeling, identical to the original superhydrophobicity. This simple preparation method is low cost, and suitable for large-scale industrialization, which may offer more opportunities for practical applications.

Advances in thermal energy storage development at the German Aerospace Center(DLR)

Thermal energy storage(TES)is a key technology for renewable energy utilization and the improvement of the energy efficiency of heat processes.Sectors include industrial process heat and conventional and renewable power generation.TES systems correct the mismatch between supply and demand of thermal energy.In the medium to high temperature range(100~1000℃),only limited storage technology is commercially available and a strong effort is needed to develop a range of storage technologies which are efficient and economical for the very specific requirements of the different application sectors.At the DLR's Institute of Technical Thermodynamics,the complete spectrum of high temperature storage technologies,from various types of sensible over latent heat to thermochemical heat storages are being developed.Different concepts are proposed depending on the heat transfer fluid(synthetic oil,water/steam,molten salt,air)and the required temperature range.The aim is the development of cost effective,efficient and reliable thermal storage systems.Research focuses on characterization of storage materials,enhancement of internal heat transfer,design of innovative storage concepts and modelling of storage components and systems.Demonstration of the storage technology takes place from laboratory scale to field testing(5 kW^1 MW).The paper gives an overview on DLR's current developments.

CHARACTERIZATION OF REGENERATED CELLULOSE MEMBRANES HYDROLYZED FROM CELLULOSE ACETATE

A series of cellulose acetate membranes were prepared by using formamide as additive, and then were hydrolyzed in 4 wt% aqueous NaOH solution for 8 h to obtain regenerated cellulose membranes. The dependence of degree of substitution, structure, porous properties, solubility and thermal stability on hydrolysis time was studied by chemical titration, Fourier transform infrared spectroscopy, scanning electron microscopy, wide-angle X-ray diffraction, and differential scanning calorimetry, respectively. The results indicated that the pore size of the regenerated cellulose membranes was slightly smaller than that of cellulose acetate membrane, while solvent-resistance, crystallinity and thermostability were significantly improved. This work provides a simple way to prepare the porous cellulose membranes, which not only kept the good pore characteristics of cellulose acetate membranes, but also possessed solvent-resistance, high crystallinity and thermostability. Therefore, the application range of cellulose acetate membranes can be expanded.

Performance of Regenerative Gas Turbine Power Plant

This study aims to investigate the effect of regeneration on the output power and the thermal efficiency of the gas turbine power plant. The effect of ambient air temperature, regeneration effectiveness, and compression ratio on the cycle thermal efficiency was also investigated. An existed gas turbine power plant of AL ZAWIA is used as a base in this study, and the calculations were carried out utilizing MATLAB code. This intensive parametric study was conducted based on the fundamental of thermodynamics and gas turbine relations considering the effect of the operation conditions (ambient air temperature, regeneration effectiveness and compression ratio). It was found that adding regeneration to the simple gas turbine cycle results in an increase in the thermal efficiency of cycle. It was also found that including regeneration in gas turbine cycle results in an increase in the output power of the cycle, and it results in a decrease in the exhaust gas temperature. The effect of the regeneration effectiveness was also predicted. It was found that increasing of regeneration effectiveness results in an increase in the output power of the cycle. It was also found that the cycle thermal efficiency increases with increasing of the regenerative effectiveness. The effect of ambient air temperature was also predicted. Increasing of the ambient air temperature results in a decrease in the thermal efficiency of the cycle.

复合改性沥青高模量热再生混合料性能研究

通过添加大比例布敦岩沥青(BRA)和苯乙烯丁二烯共聚物(SBR)改性沥青,实现热再生沥青混合料综合路用性能、动态回弹模量和抗疲劳性能的提高,基于室内试验和试验段铺筑经验,验证BRA热再生高模量沥青混合料的技术可行性。结果表明:使用3%SBR改性沥青和添加2%~8%BRA可使热再生沥青混合料的车辙试验动稳定度不小于5 000次/mm,且加载60分钟后的车辙变形量不大于2.0 mm,低温弯曲破坏应变不小于2 800με;推荐复配方案的热再生沥青混合料满足高模量沥青混合料技术指标要求。

磷酸三丁酯脱色活性炭热解再生研究

以磷酸三丁酯(TBP)脱色后的粉末废活性炭(WAC)为材料,利用高温热解的方法,以亚甲基蓝吸附量和碘值为评价指标,研究了再生温度、再生时间、再生次数对废活性炭再生效果的影响。实验结果表明,WAC的再生最优条件为500℃下再生90 min,再生4次仍能恢复其82%的亚甲基蓝吸附性能及67%的碘吸附性能。通过同步热分析仪(TG-DSC)测定活性炭的失重、吸热和放热情况;借助比表面积及孔径分析仪、傅里叶红外光谱仪(FT-IR)、扫描电子显微镜(SEM)等测试手段对再生前后的活性炭进行表征,从而验证其再生效果。对废活性炭的热解机理进行了综合分析,为湿法磷酸净化工艺流程中磷酸三丁酯脱色活性炭的热解再生提供了理论指导。

火电厂再生水中的微生物对管道的腐蚀行为研究

为探究火电厂以再生水为水源时供水管道的微生物腐蚀行为,采用环状生物膜挂片反应器,动态模拟了再生水管道运行状况,通过测定溶液pH值、电导率,试片失重,电化学参数(如氧化还原电位、极化曲线、交流阻抗)、细菌数量并结合SEM、EDS、XRD等手段研究了铁细菌(IOB)、硫酸盐还原菌(SRB)及这2种混合菌对Q235钢腐蚀的影响过程和机理。结果表明,2种细菌数量随时间的延长而增长,再生水的pH值先降后升、电导率则稳步增长,环境中的细菌数与此时管材的腐蚀速率呈正相关性,SRB是影响微生物腐蚀的主要菌种;通过EDS和XRD分析发现不同环境下的腐蚀产物主要成分:IOB时腐蚀产物以FeOOH为主,存在少量Fe_(2)O_(3)、Fe_(3)O_(4);SRB时腐蚀产物主要为氧化铁和硫化铁;而SRB+IOB共存时主要腐蚀产物为Fe_(2)O_(3)、Fe_(3)O_(4)和FeS;同时管道前期表面产生的微生物膜和腐蚀产物会抑制Q235的腐蚀,后期微生物膜失活、覆盖的腐蚀产物脱落,又会使腐蚀加速。

regeneration of thermally deactivated commercial V-W-Ti catalysts

An effective method for the regeneration of thermally deactivated commercial monolith SCR catalysts was investigated. Two types of regenerated solutions, namely NH4C1 （l mol/L） and dilute H2SO4 （0.5 tool/L）, were employed to treat the used catalyst. The effects of temperature and the regeneration process on the structural and textural properties of the catalysts were determined by X-ray diffraction, scanning electron microscopy, N2 adsorption/desorption, elemental analysis and Fourier transform infrared spectroscopy. The results suggest that the anatase phase of the used catalyst is maintained after exposure to high temperatures. Some of the catalytic activity was restored after regeneration. The catalyst regenerated by aqueous NH4C1 had a higher activity than that of the catalyst treated by dilute H2SO4. The main reason is that the NH3 generated from the decomposition of NH4C1 at high temperatures can be adsorbed onto the catalyst which promotes the reaction. The aggregated V205 were partially re-dispersed during the regeneration process, and the intrinsic oxidation of ammonia with high concentrations of O2 is a factorthat suppresses the catalytic activity.

废生物活性炭制备粉末炭的热再生效能

为实现水厂废生物活性炭资源化利用,本文将废生物活性炭研磨成粉末炭,探讨热再生温度对粉末炭理化性质的影响,观测再生粉末炭对水中典型有机污染物的去除效能。结果表明:粉末炭的热解经历了水分子脱附(35~105℃)、易挥发有机物脱附(105~400℃)和沸点较高有机物热解(400~735℃)3个过程;热再生能够显著恢复粉末炭的孔隙结构,碘值、亚甲基蓝值的恢复率分别达到83.1%、75.9%,并且恢复率随着再生温度升高逐渐升高;热再生会导致粉末炭的酸性官能团含量减少,碱性官能团含量增加,而表面氧元素含量随着再生温度升高先增加后降低;热再生降低了粉末炭水溶性有机物浸出;通过热再生能够显著提升粉末炭对原水中典型有机污染物的控制效果,有机污染物去除率提高了7.7%~35.9%。

纳米CaCO_(3)与碳粉低热固固耦合原位制备纳米CaO和CO

高温条件下固相CaO可直接与CO_(2)反应生成CaCO_(3),CO_(2)捕集率达78.57%(质量分数),是解决碳排放的高效手段。钙循环技术中如何降低CaCO_(3)分解温度、CaO再生和CO_(2)利用是关键问题。研究通过纳米CaCO_(3)和碳粉的低热固固耦合反应同时实现纳米CaO再生和CO_(2)原位转化为CO,使纳米CaCO_(3)分解温度下降46℃,分解速率提高约50%,再生的多孔纳米CaO粒径小而均匀,可再次捕集CO_(2)实现钙循环利用,由CO_(2)转化的CO可应用于工业合成气。纳米CaCO_(3)和碳粉具有原料来源广泛、价格低廉、安全性高、运输便捷等优点,该低热固固耦合反应在低成本前提下具有提高CO_(2)捕集和利用效率的潜力。

Regeneration of deactivated CeCoxO2 catalyst by simple thermal treatment

Active species loss owing to reactant stream washing is a general problem which industrial catalysts suffer from.In case of catalysts synthesized by co-precipitation method,which have active species unused in bulk phase,can be regenerated by a simple thermal treatment that leads to active species in bulk phase migration to surface of the deactivated catalysts.In this work,the influence of regeneration temperature was investigated by employing ammonium hydroxide washing to simulate reactant stream washing of CeCoxO2 catalysts for NO+CO reaction.It is found that the deactivated catalyst can be regenerated by simple thermal treatment and increasing calcination temperature could accelerate the Co species migration from the bulk phase to surface of catalysts.

Thermal defluorination behaviors of PFOS,PFOA and PFBS during regeneration of activated carbon by molten salt

Current study proposes a green regeneration method of activated carbon(AC)laden with Perfluorochemicals(PFCs)from the perspective of environmental safety and resource regeneration.The defluorination efficiencies of AC adsorbed perfluorooctanesulfonate(PFOS),perfluorooctanoic acid(PFOA)and perfluorobutanesulfonate(PFBS)using three molten sodium salts and one molten alkali were compared.Results showed that defluorination efficiencies of molten NaOH for the three PFCs were higher than the other three molten sodium salts at lower temperature.At 700°C,the defluorination efficiencies of PFOS and PFBS using molten NaOH reached to 84.2%and 79.2%,respectively,while the defluorination efficiency of PFOA was 35.3%.In addition,the temperature of molten salt,the holding time and the ratio of salt to carbon were directly proportional to the defluorination efficiency.The low defluorination efficiency of PFOA was due to the low thermal stability of PFOA,which made it difficult to be captured by molten salt.The weight loss range of PFOA was 75°C–125°C,which was much lower than PFOS and PFBS(400°C–500°C).From the perspective of gas production,fluorine-containing gases produced from molten NaOH-treated AC were significantly reduced,which means that environmental risks were significantly reduced.After molten NaOH treatment,the regenerated AC had higher adsorption capacity than that of pre-treated AC.

石墨烯碳基光热功能再生纤维素纤维制备研究

制备石墨烯分散体系作为光热功能助剂,并通过纺前注射装置将其加入再生纤维素纤维纺丝溶液中,采用湿法纺丝工艺制备石墨烯碳基光热功能再生纤维素纤维。介绍石墨烯分散体系的制备方法,并对制备的石墨烯碳基光热功能再生纤维素纤维的光热性能进行分析。结果表明:制备石墨烯分散体系具有较小的粒径和粒径分布,且分散效果良好;石墨烯碳基光热功能再生纤维素纤维具有较好的光热功能,该纤维表面温度随红外辐照时间增加和石墨烯添加量增加而逐渐升高;去除红外辐照后,温度下降速率随石墨烯添加量增加而逐步减小;该纤维对测试波长范围内的光均具有较高吸收性,远红外性能优良,远红外性能和导热系数随石墨烯增加而逐渐增大。

蓄热式废气氧化炉的焚烧方案和关键设备研究

详细介绍了蓄热式废气氧化炉的焚烧方案,主要包括蓄热式废气氧化炉的工艺流程、设备组成和蓄热体的工作模式。并采用CFD计算方法,对富氢燃料燃烧器的设计和蓄热体的传热阻力计算进行了深入研究,优选出燃烧器合适的配风结构和蓄热式废气氧化炉的最佳换向时间,并制定该蓄热式废气氧化炉装置的自控时序表,为工程设计提供指导。

再生催化裂化催化剂结构及性能

采用固定床装置制备了2种碳质量分数分别为0.25%,0.04%的再生催化裂化催化剂,利用X射线衍射仪、物理吸附仪、扫描电子显微镜等对催化剂进行表征,考察了再生过程对催化剂结构的影响,并对再生催化剂的性能进行评价。结果表明:再生过程不会影响催化剂中分子筛结构;催化剂失活的主要原因是焦炭堵塞孔道,覆盖了弱酸性活性位点,再生过程除去焦炭后,催化剂活性得到恢复;催化剂碳质量分数越低,原料油转化率越高,热裂化指数越低;再生催化剂上原料油转化率最高可达83.68%,热裂化指数仅为0.19。

长期运行下的火电厂水处理系统中阴阳树脂再生优化研究

针对火电厂树脂再生问题,采用再生优化的方法对其水处理系统中阴阳树脂进行了优化,通过对比分析优化前后阴阳树脂再生效率、离子交换速度和阳树脂交换容量等参数,验证了优化后的再生方式可以有效提高其再生效率,延长阴树脂使用寿命。实验结果表明,当温度为30℃时,采用化学再生方式进行树脂再生效率可提高20%以上。因此,在不改变离子交换容量的前提下提高阴阳树脂再生效率的方法,能够为之后的水处理系统提供助力。