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Experimental Study of the Particulate Dirt Characteristics on Pipe Heat Transfer Surface
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作者 YANG Qirong ZHANG Zhenglin +2 位作者 YAO Erren ZHANG Ning LI Nan 《热科学学报:英文版》 SCIE EI CAS CSCD 2019年第5期1054-1064,共11页
The systematic study of the particulate dirt characteristics on heat exchanging surface can provide theoretical guidance for defouling. In this paper, four main compositions of particulate dirt in the treated city sew... The systematic study of the particulate dirt characteristics on heat exchanging surface can provide theoretical guidance for defouling. In this paper, four main compositions of particulate dirt in the treated city sewage(i.e., CaCO3, MgO, CaSO4 and SiO2) are selected as the research objects. The effects of different working conditions, characteristics of particles on the growth rules of particulate dirt and the synergistic fouling by different particles are researched by thermal resistance method experimentally, while the microstructures of the dirt are observed by Scanning Electron Microscope(SEM). The asymptotic values of both dirt thermal resistance and the scaling rate decrease with the increasing of working fluid velocity, while the two asymptotic values increase with the increasing particle size and particle concentration. Although the working fluid import temperature shows a weaker influence on the thermal resistance, but the increase of working fluid import temperature can retard the fouling rate. Among the stable values of the thermal resistances of four types of fouling, SiO2 is the largest and Mg O is the smallest. The synergistic fouling by different types of particles results in the denser structure of mixed fouling. 展开更多
关键词 PARTICULATE FOULING growth rule FOULING thermal resistance FOULING rate SYNERGISTIC FOULING
Comparative studies on fouling of homogeneous anion exchange membranes by different structured organics in electrodialysis
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作者 Zhijuan Zhao Shaoyuan Shi +2 位作者 Hongbin Cao Yujiao Li Bart Van der Bruggen 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第3期218-228,共11页
Five negatively charged organic compounds with different structures, sodium methane sulfonate(MS), sodium benzene sulfonate(BS), sodium 6-hydroxynaphthalene-2-sulfonate(NSS), sodium dodecyl sulfate(SDS), and sodium do... Five negatively charged organic compounds with different structures, sodium methane sulfonate(MS), sodium benzene sulfonate(BS), sodium 6-hydroxynaphthalene-2-sulfonate(NSS), sodium dodecyl sulfate(SDS), and sodium dodecyl benzene sulfonate(SDBS), were used to examine the fouling of an anion exchange membrane(AEM) in electrodialysis(ED),to explore the effect of molecular characteristics on the fouling behavior on the AEM and changes in the surface and electrochemical properties of the AEM. Results indicated that the fouling degree of the AEM by the different organics followed the order:SDBS > SDS > NSS > BS > MS. SDBS and SDS formed a dense fouling layer on the surface of the AEM, which was the main factor in the much more severe membrane fouling, and completely restricted the transmembrane ion migration. The other three organics caused fouling of the AEM by adsorption on the surface and/or accumulation in the interlayer of the AEM, and exhibited almost no influence on the transmembrane ion migration. It was also concluded that the organics with benzene rings caused more severe fouling of the AEM due to the stronger affinity interaction and steric effect between the organics and the AEM compared with organics with aliphatic chains. 展开更多
关键词 ANION exchange MEMBRANE Different structural ORGANICS MEMBRANE FOULING Property characterization FOULING mechanism analyses
Characterization of dissolved organic matter and membrane fouling in coagulation-ultrafiltration process treating micro-polluted surface water
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作者 Fan Bu Baoyu Gao +2 位作者 Qinyan Yue Xue Shen Wenyu Wang 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第1期318-324,共7页
Coagulation-ultrafiltration (C-UF)is widely used for surface water treatment.With the removal of pollutants,the characteristics of organic matter change and affect the final treatment efficiency and the development of... Coagulation-ultrafiltration (C-UF)is widely used for surface water treatment.With the removal of pollutants,the characteristics of organic matter change and affect the final treatment efficiency and the development of membrane fouling.In this study,we built a dynamic C-UF set-up to carry out the treatment of micro-polluted surface water,to investigate the characteristics of dissolved organic matter from different units.The influences of poly aluminum chloride and poly dimethyldiallylammonium chloride (PDMDAAC)on removal efficiency and membrane fouling were also investigated.Results showed that the dosage of PDMDAAC evidently increased the UV254 and dissolved organic carbon removal efficiencies, and thereby alleviated membrane fouling in the C-UF process.Most hydrophobic bases (HOB) and hydrophobic neutral fractions could be removed by coagulation.Similarly,UF was good at removing HoB compared to hydrophilic substances (HIS)and hydrophobic acid (HoA) fractions.HiS and HoA fractions with low molecule weight accumulated on the surface of the membrane,causing the increase of transmembrane pressure (TMP).Membrane fouling was mainly caused by a removable cake layer,and mechanical cleaning was an efficient way to decrease the TMP. 展开更多
关键词 COAGULATION ULTRAFILTRATION Dissolved organic MATTER Membrane FOULING
Floc structure and membrane fouling affected by sodium alginate interaction with Al species as model organic pollutants
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作者 Xuejun Xiong Hui Xu +4 位作者 Beiping Zhang Xiaohui Wu Hongyan Sun Dongsheng Wang Zhengyang Wang 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第8期1-13,共13页
Membrane filtration combined with pre-coagulation has advantages in advanced wastewater treatment. As a model of a microbial polysaccharide, research on the effect of sodium alginate(SA) on alum hydrolysis has been ra... Membrane filtration combined with pre-coagulation has advantages in advanced wastewater treatment. As a model of a microbial polysaccharide, research on the effect of sodium alginate(SA) on alum hydrolysis has been rare;therefore, it is necessary to gain insight into the interface interaction between SA molecules and Al species, and the role SA plays during floc formation. In this study, the interaction mechanism between SA and Al species has been investigated, by evaluating the effect of SA on floc characteristics and membrane fouling during coagulation–ultrafiltration with different Al species coagulants(AlCl3 and preformed Al13). Al 2 p X-ray photoelectron spectroscopy(XPS) confirmed that the complexation of ligands and Al species strongly affects the reaction pathways for Al hydrolysis and the final nature of the flocs, as Al13 can be decomposed into octahedral precipitates when SA is added. The presence of SA can affect floc properties, which have important impacts on the characteristics of the cake layer and membrane fouling. Due to the bridging ability of SA, the floc strength increased by about 50% using Ala, which was much better than preformed Al13, with a percentage increase of only about 6%. Moreover,the recovery factor of HA-flocs was decreased from 96% to 43% with SA addition of 0.5 mg/L.It was concluded that SA can affect the characteristics of the cake layer and membrane fouling through participating in the formation of primary flocs and altering the Al hydrolysis pathway. 展开更多
关键词 Coagulation–ultrafiltration process AL SPECIES Interface INTERACTION X-ray photoelectron spectroscopy FLOC properties Membrane fouling
60000Nm^3/h制氧机氮水预冷系统在线清洗的应用 预览
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作者 赵洪涛 许宇 +2 位作者 李富森 王超 张婷 《莱钢科技》 2019年第1期55-56,共2页
60000Nm^3/h制氧机是天元气体的主力机组,氮水预冷系统冷却效果降低影响机组的稳定运行,停车处理将会直接影响热线生产。通过氮水预冷系统实现在线清洗,避免了因换热效果差造成系统停车,提升空分系统整体能源利用效率,保障了热线生产的... 60000Nm^3/h制氧机是天元气体的主力机组,氮水预冷系统冷却效果降低影响机组的稳定运行,停车处理将会直接影响热线生产。通过氮水预冷系统实现在线清洗,避免了因换热效果差造成系统停车,提升空分系统整体能源利用效率,保障了热线生产的安全稳定。 展开更多
关键词 氮水预冷系统 在线清洗 污垢
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江水源热泵换热管内污垢分析及在线清洗研究 预览
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作者 杨艳 桂树强 +1 位作者 颜俊 李东阳 《建筑热能通风空调》 2019年第4期70-72,共3页
江水源热泵利用地表水作为冷热源是一种清洁高效的空调系统。本文阐述了江水源热泵换热管内污垢形成原理,分析了江水源热泵换热管内污垢形成影响因素,最后对比了两种江水源热泵换热管内污垢在线处理方法的优缺点。
关键词 江水源热泵 换热管 污垢 在线处理
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Aggravation of membrane fouling and methane leakage by a three-phase separator in an external anaerobic ceramic membrane bioreactor
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作者 Chao Pang Chunhua He +2 位作者 Zhenhu Hu Shoujun Yuan Wei Wang 《环境科学与工程前沿(英文)》 SCIE EI CAS CSCD 2019年第4期35-43,共9页
The three-phase separator is a critical component of high-rate anaerobic bioreactors due to its significant contribution in separation of biomass, wastewater, and biogas. However, its role in an anaerobic membrane bio... The three-phase separator is a critical component of high-rate anaerobic bioreactors due to its significant contribution in separation of biomass, wastewater, and biogas. However, its role in an anaerobic membrane bioreactor is still not clear. In this study, the distinction between an external anaerobic ceramic membrane bioreactor (EAnCMBR) unequipped (R1) and equipped (R2) with a three-phase separator was investigated in terms of treatment performance, membrane fouling, extracellular polymers of sludge, and microbial community structure. The results indicate that the COD removal efficiencies of Rl and R2 were 98.2%±0.4% and 98.1%±0.4%, respectively, but the start-up period of R2 was slightly delayed. Moreover, the membrane fouling rate of R2 (0.4 kPa/d) was higher than that of Rl (0.2 kPa/d). Interestingly, the methane leakage from R2 (0.1 L/d) was 20 times higher than that from Rl (0.005 L/d). The results demonstrate that the three-phase separator aggravated the membrane fouling rate and methane leakage in the EAnCMBR. Therefore, this study provides a novel perspective on the effects of a three-phase separator in an EAnCMBR. 展开更多
关键词 ANAEROBIC MEMBRANE BIOREACTOR Three-phase separator MEMBRANE fouling METHANE LEAKAGE Sludge property
Ozonation as an efficient pretreatment method to alleviate reverse osmosis membrane fouling caused by complexes of humic acid and calcium ion
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作者 Xuehao Zhao Yinhu Wu +6 位作者 Xue Zhang Xin Tong Tong Yu Yunhong Wang Nozomu Ikuno Kazuki Ishii Hongying Hu 《环境科学与工程前沿(英文)》 SCIE EI CAS CSCD 2019年第4期89-100,共12页
Humic acid has been considered as one of the most significant sources in feed water causing organic fouling of reverse osmosis (RO) membranes, but the relationship between the fouling behavior of humic acid and the ch... Humic acid has been considered as one of the most significant sources in feed water causing organic fouling of reverse osmosis (RO) membranes, but the relationship between the fouling behavior of humic acid and the change of its molecular structure has not been well developed yet. In this study, the RO membrane fouling behavior of humic acid was studied systematically with ozonation as a pretreatment method to control RO membrane fouling. Furthermore, the effect of ozone on the structure ofhumic acid was also explored to reveal the mechanisms. Humic acid alone (10-90 mg/L, in deionized water) was found not to cause obvious RO membrane fouling in 45-h operation. However, the presence of Ca^2+ aggravated significantly the RO membrane fouling caused by humic acid, with significant flux reduction and denser fouling layer on RO membrane, as it was observed by scanning electron microscope (SEM) and atomic force microscope (AFM). However, after the pretreatment by ozone, the influence of Ca^2+ was almost eliminated. Further analysis revealed that the addition of Ca^2+ increased the particle size of humic acid solution significantly, while ozonation reduced the SUVA254, particle size and molecular weight of the complexes of humic acid and Ca^2+(HA-Ca^2+ complexes). According to these results and literature, the bridge effect of Ca^2+ aggregating humic acid molecules and the cleavage effect of ozone breaking HA-Ca^2+ complexes were summarized. The change of the structure of humic acid under the effect of Ca^2+ and ozone is closely related to the change of its membrane fouling behavior. 展开更多
关键词 Reverse osmosis Membrane FOULING HUMIC acid Ca^2+ Ozone
Application of a hybrid gravity-driven membrane filtration and dissolved ozone flotation(MDOF)process for wastewater reclamation and membrane fouling mitigation
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作者 Xin Jin Wei Wang +5 位作者 Shuai Wang Pengkang Jin Xiaochang C.Wang Wushou Zhang Weijun An Yong Wang 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第7期17-27,共11页
This study proposed a novel membrane filtration and dissolved ozone flotation integrated(MDOF) process and tested it at pilot scale. Membrane filtration in the MDOF process was operated in gravity-driven mode, and req... This study proposed a novel membrane filtration and dissolved ozone flotation integrated(MDOF) process and tested it at pilot scale. Membrane filtration in the MDOF process was operated in gravity-driven mode, and required no backwashing, flushing, or chemical cleaning. Because ozone was added in the MDOF process, ozonation, coagulation, and membrane filtration could occur in a single reactor. Moreover, in situ ozonation occurred in the MDOF process, which differs from the conventional pre-ozonation membrane filtration process. Significant enhancement of turbidity removal was further achieved through the addition of membrane filtration. Membrane fouling was mitigated in the MDOF process compared to the MDAF process. In situ ozonation in the MDOF process decreased the fluorescence intensity and transformed the high MW dissolved organics into small MW compounds. For the fouling layer, the extracellular polymeric substance(EPS) contents and cake layer morphology were analyzed. The results indicated that the contents of EPS decreased. Furthermore, a thinner and more loosely structured cake layer formed in the MDOF process. Because coagulation and ozonation occurred simultaneously in a single reactor, the generation of hydroxyl radicals was enhanced through the catalytic effect of Al-based coagulants on ozone decomposition, which further alleviated membrane fouling in the MDOF process. 展开更多
关键词 Dissolved OZONE FLOTATION Gravity-driven MEMBRANE filtration MEMBRANE fouling In situ ozonation
Influence of pore size and membrane surface properties on arsenic removal by nanofiltration membranes
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作者 Nathalie Tanne Rui Xu +3 位作者 Mingyue Zhou Pan Zhang Xiaomao Wang Xianghua Wen 《中国环境科学与工程前沿:英文版》 SCIE EI CAS CSCD 2019年第2期55-62,共8页
Nanofiltration(NF)has a great potential in removing arsenate from contaminated water.The performance including arsenate rejection,water permeability and resistance to fouling could however differ substantially among N... Nanofiltration(NF)has a great potential in removing arsenate from contaminated water.The performance including arsenate rejection,water permeability and resistance to fouling could however differ substantially among NF membranes.This study was conducted to investigate the influence of membrane pore size and surface properties on these aspects of membrane performance.Four fullyaromatic NF membranes with different physicochemical properties were adopted for this study.The results showed that surface charge,hydrophobicity,roughness and pore size could affect water permeability and/or arsenate rejection considerably.A more negative surface charge was desirable to enhance arsenate rejection rates.NF90 and a non-commercialized membrane(M#1)demonstrated the best performance in terms of arsenate rejection and water permeability.The M#1 membrane showed less membrane fouling than NF90 when used for filtration of real arsenic-containing groundwater.This was mainly due to its distinct chemical composition and surface properties.A severe membrane fouling could lead to a substantial reduction of arsenic rejection.The M#1 membrane showed the best performance,which indicated that membrane modification could indeed enhance the overall membrane performance for water treatment. 展开更多
关键词 ARSENATE NANOFILTRATION DRINKING water MEMBRANE PROPERTY MEMBRANE FOULING
电站锅炉省煤器受热面的积灰监测 预览
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作者 肖海平 陈裕辉 +3 位作者 葛金林 王晓宁 席建林 刘利宁 《化工进展》 EI CAS CSCD 北大核心 2019年第3期1573-1578,共6页
为了实现电站锅炉省煤器受热面的污染情况在线监测,采用支持向量机算法对省煤器的清洁吸热量进行预测,使用灰狼算法(GWO)和遗传算法对模型进行参数寻优并进行预测精确度的对比。再由清洁吸热量计算清洁因子,根据清洁因子的变化来判断省... 为了实现电站锅炉省煤器受热面的污染情况在线监测,采用支持向量机算法对省煤器的清洁吸热量进行预测,使用灰狼算法(GWO)和遗传算法对模型进行参数寻优并进行预测精确度的对比。再由清洁吸热量计算清洁因子,根据清洁因子的变化来判断省煤器的积灰状态。以某660MW机组为例,将短吹后的数据作为清洁数据样本进行训练和验证,结果表明灰狼算法比遗传算法预测精度更高,所需训练时间更短。最后利用上述模型来预测长吹前省煤器的清洁吸热量,绘制出清洁曲线图。该模型能较好表现省煤器的积灰情况,为受热面积灰在线监测提供依据。 展开更多
关键词 电站燃煤锅炉 省煤器 积灰 支持向量机 灰狼算法 清洁因子
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电絮凝-高效澄清池联合技术在循环水排污水处理中的应用 预览
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作者 康少鑫 张彬彬 +1 位作者 孙军峰 叶治安 《热力发电》 CAS 北大核心 2019年第4期104-109,共6页
为减轻高分子絮凝剂、助凝剂对膜处理系统的污堵,强化循环水排污水混凝澄清效果,北方某热电厂采用了电絮凝-高效澄清池联用技术对其循环水排污水进行预处理。通过系统调试,考察了不同电流密度、凝聚池pH值及碳酸钠加药量下,澄清池出水... 为减轻高分子絮凝剂、助凝剂对膜处理系统的污堵,强化循环水排污水混凝澄清效果,北方某热电厂采用了电絮凝-高效澄清池联用技术对其循环水排污水进行预处理。通过系统调试,考察了不同电流密度、凝聚池pH值及碳酸钠加药量下,澄清池出水浊度、总硬度及总碱度的变化情况。结果表明,在电流密度为5.96 A/m^2,凝聚池pH值约为11.0,碳酸钠加药量为170 mg/L时,电絮凝-高效澄清池对浊度、总硬度和总碱度去除率分别约为90%、60%和66%,平均出水浊度为0.9 NTU,总硬度为9.7 mmol/L,总碱度为1.2 mmol/L,出水水质稳定,满足后续膜处理工艺进水水质要求,并降低了后续膜系统污堵的风险。 展开更多
关键词 循环水排污水 电絮凝 高效澄清池 浊度 总硬度 总碱度 污堵
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Optimized coagulation pretreatment alleviates ultrafiltration membrane fouling: The role of floc properties and slow-mixing speed on mechanisms of chitosan-assisted coagulation
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作者 Peng Du Xing Li +6 位作者 Yanling Yang Zhaoyang Su Hang Li Nan Wang Tingting Guo Tingting Zhang Zhiwei Zhou 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第8期82-92,共11页
To alleviate ultrafiltration(UF) membrane fouling, the pre-coagulation of poly-aluminum chloride(PACl) with the aid of chitosan(CTS) was conducted for synthetic humic acid–kaolin water treatment. Pre-coagulation of t... To alleviate ultrafiltration(UF) membrane fouling, the pre-coagulation of poly-aluminum chloride(PACl) with the aid of chitosan(CTS) was conducted for synthetic humic acid–kaolin water treatment. Pre-coagulation of three molecular weights(MW) CTSs(50–190 kDa(CTSL), 190–310 kDa(CTSM) and 310–375 kDa(CTSH)) was optimized with slow-mixing speeds of 30, 60 and 90 r/min, respectively. The removal efficiency and floc properties as well as membrane fouling were analyzed, and were compared to results obtained by conventional coagulation with PACl. Results showed that variations in floc properties could be ascribed to the coagulation mechanisms of CTS_L/CTS_M/CTS_H at different slow-mixing speeds, resulting in reduced UF membrane fouling. Specifically, at the low speed of 30 r/min, all three CTS types produced flocs with similar properties, while CTSLresulted in the lowest removal efficiency and aggravated irreversible fouling. At the appropriate speed of 60 r/min, CTSMgenerated the most compact flocs with the combined effects of bridging and path mechanisms. The compact cake layer formed could alleviate irreversible fouling,which was beneficial for prolonging the operation of the UF membrane. At the high speed of90 r/min, CTSHformed fragile flocs and aggravated irreversible membrane fouling. We considered membrane fouling to be affected by floc properties and the resultant removal efficiency, which was governed by the MW of the CTS used and the slow-mixing speed applied as well. 展开更多
关键词 Coagulation–ultrafiltration Membrane fouling FLOC PROPERTIES Chitosan Slow-mixing SPEED
Effect of chemical dose on phosphorus removal and membrane fouling control in a UCT-MBR
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作者 Guangrong Sun Chuanyi Zhang +3 位作者 Wei Li Limei Yuan Shilong He Liping Wang 《中国环境科学与工程前沿:英文版》 SCIE EI CAS CSCD 2019年第1期27-37,共11页
To enhance phosphorus removal and make the effluent meet the strict discharge level of total phosphorus (TP, 0.5 mg/L), flocculant dosing is frequently applied. In this study, the performance of aluminum sulfate dosin... To enhance phosphorus removal and make the effluent meet the strict discharge level of total phosphorus (TP, 0.5 mg/L), flocculant dosing is frequently applied. In this study, the performance of aluminum sulfate dosing in a University of Cape Town Membrane Bioreactor (UCT-MBR) was investigated, in terms of the nutrients removal performance, sludge characteristics and membrane fouling. The results indicated that the addition of aluminum sulfate into the aerobic reactor continuously had significantly enhanced phosphorus removal. Moreover, COD, NH4+^-N and TN removal were not affected and effluent all met the first level A criteria of GB18918-2002. In addition, the addition of aluminum sulfhte had improved the sludge activity slightly and reduced transmembrane pressure (TMP) increase rate from 1.13 KPa/d to 0.57 KPa/d effectively. The alleviation of membrane fouling was attributed to the increased average particle sizes and the decreased accumulation of the small sludge particles on membrane surface. Furthcnnorc, the decline of extracellular polymeric substance (EPS) concentration in mixed sludge liquid decreased its accumulation on membrane surface, resulting in the mitigation of membrane fouling directly. 展开更多
关键词 University of CAPE Town MEMBRANE BIOREACTOR (UCT-MBR) Enhanced nutrients removal Aluminum sulfate Sludge activity MEMBRANE FOULING
CPR1000机组蒸汽发生器裕度问题分析 预览
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作者 柴伟东 赵清森 《热力发电》 CAS 北大核心 2019年第3期126-131,共6页
国内新投产的CPR1000机组普遍存在蒸汽发生器(SG)裕度试验不满足验收准则要求的问题,表现为蒸汽发生器出口压力低,已影响到汽轮机出力。对此,本文通过设计分析、试验验证和现场视频检查等手段进行了系统分析。以Framtone公司和Westingho... 国内新投产的CPR1000机组普遍存在蒸汽发生器(SG)裕度试验不满足验收准则要求的问题,表现为蒸汽发生器出口压力低,已影响到汽轮机出力。对此,本文通过设计分析、试验验证和现场视频检查等手段进行了系统分析。以Framtone公司和Westinghouse公司设计的55/19型、60F型和Δ125型蒸汽发生器为研究对象,利用设计数据搭建数学模型,对传热面积进行了校核计算;考察了堵管率、一回路流量和一回路平均温度对蒸汽发生器出口压力的影响;验证计算了早期及新投产核电厂蒸汽发生器裕度试验数据;最后根据现场对蒸汽发生器的视频检查情况,确定新投产的CPR1000机组裕度考核不合格的根本原因为二次侧的结垢。 展开更多
关键词 CPR1000 蒸汽发生器 传热面积 裕度 结垢 堵管率 流量 出口压力
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Review on structural control and modification of graphene oxide-based membranes in water treatment: From separation performance to robust operation
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作者 Ning Zhang Wenxu Qi +5 位作者 Lili Huang En Jiang Junjiang Bao Xiaopeng Zhang Baigang An Gaohong He 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第6期1348-1360,共13页
Membrane separation has become an important technology to deal with the global water crisis. The polymerbased membrane technology is currently in the forefront of water purification and desalination but is plagued wit... Membrane separation has become an important technology to deal with the global water crisis. The polymerbased membrane technology is currently in the forefront of water purification and desalination but is plagued with some bottlenecks. Laminated graphene oxide(GO) membranes exhibit excellent advantages in water purification and desalination due to the single atomic layer structure, hydrophilic property, rich oxygen-containing groups for modification, mechanical and chemical robust, anti-fouling properties, facile and large-scale production, etc. Thus the GO-based membrane technology is believed to offer huge opportunities for efficient and practical water treatment. This review systematically summarizes the current progress on the water flux and selectivity intensification, stability improvement, anti-fouling and anti-biofouling ability enhancement by structural control and modification. To improve the performance of the laminated GO membrane, interlayer spacing tunability and surface modification are mainly used to enhance its water flux and selectivity. It is found that the stability and biofouling also block the service life of the GO membrane. The crosslinking method is found to effectively solve the stability of GO membrane in aqueous environment. Introducing nanoparticles is a widely used method to improve the membrane biofouling ability. Overall, we believe that this review could provide benefit to researchers in the area of GO-based membrane technology for water treatment. 展开更多
关键词 Membranes Graphene OXIDE Water FLUX SELECTIVITY Stability FOULING
加氢裂化原料油换热器结垢分析 预览
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作者 张帅 《化工管理》 2019年第19期100-101,共2页
文章主要针对武汉石化180万吨/年加氢裂化装置高压原料油换热器的结垢问题进行了分析。运用Aspen软件计算了其传热系数和污垢热阻,分析了产生污垢的原因并提出了相应的对策。计算结果表明,目前换热器总污垢热阻值增加到0.002m2·K&#... 文章主要针对武汉石化180万吨/年加氢裂化装置高压原料油换热器的结垢问题进行了分析。运用Aspen软件计算了其传热系数和污垢热阻,分析了产生污垢的原因并提出了相应的对策。计算结果表明,目前换热器总污垢热阻值增加到0.002m2·K·W-1,总传热系数为254 W·m-2·K-1。为此,提出了延长换热器使用寿命的主要措施,其中包括:控制原料油与尾油的换热温度,增大换热器管程出口的传热温差,加强对原料油性质的监控,减少污垢前驱体的生成,持续加注阻垢剂和增大流体流动速率。 展开更多
关键词 加氢换热器 污垢 热阻传热系数 ASPEN
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苯乙烯装置三联换热器结垢原因分析 预览
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作者 史刚 《炼油技术与工程》 CAS 2019年第9期31-34,共4页
苯乙烯装置三联换热器是关键的余热回收设备,三联换热器内部结垢直接影响设备性能以及使用寿命。借助FTIR,XRF及GC-MS等多种分析方法对三联换热器处垢样的结构进行解析,结果表明垢样主要组分为聚苯乙烯,其质量分数达到89%~90%,其次为稠... 苯乙烯装置三联换热器是关键的余热回收设备,三联换热器内部结垢直接影响设备性能以及使用寿命。借助FTIR,XRF及GC-MS等多种分析方法对三联换热器处垢样的结构进行解析,结果表明垢样主要组分为聚苯乙烯,其质量分数达到89%~90%,其次为稠环芳烃类重组分,其质量分数为9%~10%。垢样中不含AMS以及DVB类有害杂质,但含有0.8%~0.9%(质量分数)的亚铁离子。根据样品的结构解析结果推断三联换热器结垢问题主要产生在脱氢反应单元正压生产期间,其次脱氢催化剂流失铁元素中的亚铁离子可能对结垢问题的产生起到催化作用。 展开更多
关键词 苯乙烯 三联换热器 结垢 聚合反应 亚铁离子
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两大矿区准东煤结渣和沾污特性对比研究 预览
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作者 杨海亮 《发电设备》 2019年第4期233-236,共4页
通过燃烧试验研究了五彩湾矿区与将军庙矿区准东煤的结渣和沾污特性,结果表明五彩湾煤灰中Ca含量较高且较易结渣,将军庙煤灰中Fe含量较高且较易沾污,在燃烧利用中应区别对待。
关键词 准东煤 结渣 沾污
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准东煤混烧过程中结渣沾污特性研究 预览
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作者 郭万贵 《锅炉技术》 北大核心 2019年第2期11-15,共5页
针对准东煤在实际电厂燃烧过程中的强结渣、强沾污问题,选取了典型的高Ca、高Na南矿煤为研究对象。在0.4 MW燃烧试验台上进行了准东煤结渣特性试验研究,并通过添加不同比例的将军庙煤来研究混烧对煤灰结渣、沾污特性的影响。研究结果表... 针对准东煤在实际电厂燃烧过程中的强结渣、强沾污问题,选取了典型的高Ca、高Na南矿煤为研究对象。在0.4 MW燃烧试验台上进行了准东煤结渣特性试验研究,并通过添加不同比例的将军庙煤来研究混烧对煤灰结渣、沾污特性的影响。研究结果表明:纯烧南矿煤时结渣较为严重,灰渣呈现灰褐色,且质地较为疏松,其不同区域的灰渣主要以Ca的低温化合物为主;沾污样呈现亮白色,主要以硫酸钠为主。添加将军庙煤后,煤灰中的Al、Si与Ca、Na发生强烈的交互反应,生成高熔点的硅铝酸盐类物质,结渣和沾污倾向大为减缓。最终结果表明:实际电厂再燃用南矿煤时,可部分掺烧(10%~20%)将军庙煤,能够明显减缓煤灰的结渣沾污强度。 展开更多
关键词 准东煤 混烧 结渣特性 沾污特性
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