Processes
·
2022
·Vol. 11
·期 1
·102
·
IF 3.352
Libo Liu,Qiming Zhuo,Hongxiang Xu,Donghui Wang
The accurate determination of the coal slime filter cake pore structure has always been a problem in the field of solid–liquid separation. An innovative measurement method for the pore structure of filter cake after filtration dehydration of coal slime water, including the preparation of coal slime filter cake, the solidification of the filter cake, and the preparation and measurement of test filter cake, was established in this paper. Epoxy resin and curing agent can ensure the strength of the filter cake, and red colorant can realize the accurate separation of coal particles and pores. The most suitable perfusate consists of epoxy resin, red colorant, and curing reagent, and the optimal ratio is 12:3:5. The application of the method to the study of the effect of filtration time on the coal slime filter cake pores shows that the modified method is effective. At the initial stage of filtration, intergranular pores formed by coarse particles are the main pores. With increasing filtration time, the macropores formed by the coarse particles are mainly filled with fine particles, and the pore size of the filter cake rapidly decreases. These measuring results and rules are accurate. This method can be conveniently used to study the microstructure of filter cake, pore channel regulation, filtration dehydration mechanisms, etc.Keywords:pore structure;coal slime filter cake;solidification;filtration time
研究领域:
矿业工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2022
·Vol. 12
·期 18
·11402-11412
·
IF 4.036
Zhaofeng Xue,Miaomiao Hu,Xia Miao,Long Zang,Jintang Guo
The high temperature of formation and multiple stages of leakage zone seriously affect the efficiency and safety of drilling and cementing operations. To improve leakage plugging quality before the cementing process, the hydrophobic associating polymer PHAAO was synthesized from acrylamide (AM), 2-acrylamide-2-methyl propane sulfonic acid (AMPS), and the long side-chain hydrophobic monomer octadecyl dimethyl allyl ammonium chloride (ODAAC) in this study. The structure and molecular weight of the polymer were characterized, and it was proved that the polymer has strong association properties and excellent heat resistance. Utilizing the bridge plugging principle, the polymer PHAAO was used with 36-mesh walnut shells and lignin fiber to form a compound plugging agent. This agent was added to spacer fluid to become a plugging spacer. API water loss tests and loading capacity tests under high temperatures show that the filter cake formed by the spacer fluid is dense. The sealing pressure of the spacer fluid on a 1 mm crack can reach 6.5 MPa at 160 °C, and it has good compatibility with cement slurry. A scanning electron microscopy (SEM) test was conducted to explore the membrane formation mechanism of the polymer. An ultra-low permeability membrane is formed on the surface of the filter cake from the spacer fluid due to the hydrophobic association and hydrogen bonding between the polymer and lignin fiber, thereby greatly reducing the loss of spacer fluid.
研究领域:
石油工程
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2018
·
IF 6.578
Wenyu Wang,Qinyan Yue,Kangying Guo,Fan Bu,Xue Shen,Baoyu Gao
The membrane fouling is a challenge for the application of ultrafiltration , one of which the cake layer is the main influencing factor. However, the pros and cons of cake layer generated in the coagulation-ultrafiltration (C-UF) process needs to be explored. This study was carried out to investigate that the effect of a cake layer on the membrane fouling behavior with three Al species coagulants for different effluents. The results indicated that the fouling mechanisms of cake layer under different effluents conditions were diverse due to the particle characteristics. The Al hydrolysis that accompanied by the interaction between Al species coagulants and the –OH/-COOH functional groups of humic acid were conducted, and the effluents of Al a presented lighter membrane fouling. Meanwhile, the components mainly trapped by the membrane were soluble microbial products, protein, polypeptides and amino acid-like materials during C-UF process, because of the decrease in the proportion of fluorescence response. For the less/compact cake layer (system 2), the average of the external and internal membrane resistances were about 25 × 10 10 m −1 and 21 × 10 10 m −1 , respectively, which caused severe membrane fouling. It was concluded that the poriferous/loose cake layer could effectively alleviate membrane fouling by re-adsorbing some organic matters.
研究领域:
环境科学
·
水处理工程
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
·
2012
·Vol. 88
·期 3
·437-443
·
IF 2.168
Min Jia,Hongmin Cui,Weiqun Jin,Lili Zhu,Yu Liu,Ji Chen
BACKGROUND: Rhenium is a rare and valuable metal coexisting with molybdenum in molybdenite and sulfide copper ores and is hard to separate. Methods such as solvent extraction, ion exchange, adsorption, precipitation, etc. have been used to separate and purify Re(VII), and resin ion exchange has been widely investigated and used owing to its convenient operation and relatively low-cost. The main challenge comes from the preparation of resins having high performance and stability. In an earlier study, an N-methylimidazolium functionalized strong basic anion exchange resin was successfully synthesized and used for Cr(IV) extraction. This paper, reports on further synthesis and application of this resin for adsorption and separation of Re(VII) and Mo(VI), especially from copper arsenic filter cake. RESULTS: At pH 6.25, Re(VII) and Mo(VI) can be effectively separated with the N-methylimidazolium functionalized strong basic anion exchange resin, giving a Re(VII) recovery of up to 93.3%, but only 5.1% for Mo(VI). When using the copper arsenic filter cake sample 89.1% Re(VII) recovery was achieved. CONCLUSION: The N-methylimidazolium functionalized strong basic anion exchange resin exhibited high selectivity and recovery for Re(VII) in a mixed system. © 2012 Society of Chemical Industry
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2025
·
IF 9
Yang Zhang,Ziyi Meng,Dongqing Yan,Peng Sun,Qianyu Shang,Ying Liu,Jingang Yao,Jun Wang
Piezoelectric membranes have attracted increasing attention due to their potential to offer pressure-responsive and electromechanical coupling functionalities in pressure-driven filtrations. Despite demonstrated antifouling effectiveness against model foulants, their practical performance within realistic and integrated treatment processes remains inadequately explored. Herein, a piezoelectric PVDF/GO ultrafiltration membrane (PEM) was fabricated and integrated into an online coagulation–ultrafiltration (C–UF) system to mitigate cake layer fouling. During pressure-driven filtration processes, the PEM not only exhibited a self-powered capability with oscillatory output signals (e.g., ∼0.4 V at 30 kPa), but also demonstrated a tunable and markedly enhanced response under dynamic pressure gradients (e.g., ∼1.1 V with a pressure gradient of 2 kPa/s). Based on these observations, a dynamic-pressure-control (DPC) strategy was developed for real-time regulation of piezoelectric output, adaptively responding to the stage-wise progression of cake fouling. Compared with the control membrane, the PEM under DPC operation exhibited ∼60 % lower irreversible filtration resistance and nearly threefold greater cake porosity. Moreover, implementing the DPC procedure for just 3 min per cycle enabled the PEM to sustain robust self-cleaning performance and enhanced permeate quality throughout a multi-cycle filtration test, achieving ∼50 % lower filtration resistance compared to physical cleaning method. Mechanistic analysis suggested that, under piezoelectric activation, the altered floc deposition dynamics and polarization-induced reorganization may act synergistically to shape both the structure and composition of the cake matrix, thereby inhibiting cake growth and subsequent compaction. This work provides a practical operational guidance for retrofitting PEM technology into existing C–UF systems, representing a viable strategy for advancing the application of piezoelectric membranes.
研究领域:
膜技术
·
水处理
·
压电材料
·
环境工程
·
分离过程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Shuang Yi,Yinfeng Xu,Yuqing Cao,Hui Mao,Gang He,Huaqiang Shi,Xiaoling Li,Hua Dong
To elucidate the effects of filtration reducers’ surface charge on drilling fluid filtration performance, three kinds of SiO 2 @polymer nanoparticles with different surface charges are prepared. When these nanoparticles are added into bentonite-based drilling fluids as filtration reducers, the negatively charged nanoparticles show the best filtration reduction performance while the positively charged nanoparticles show the most inferior filtration reduction performance. Moreover, more negative charges induce better filtration reduction performance. Conversely, more positive charges induce more inferior filtration reduction performance. The filtration performance of drilling fluids is decided by the compactness of the filter cake. And the interactions among the particles in the drilling fluids play an important role in affecting the compactness of filter cake. The electrostatic attraction forces between the positively charged nanoparticles and negatively charged bentonite particles promoted the aggregation before the formation of incompact filter cake, and the electrostatic repulsion forces between the negatively charged nanoparticles and negatively charged bentonite particles slowed down the aggregation of particles to form more compact filter cakes. These findings demonstrate the decisive role of surface charge of filtration reducers, which could provide guidance for searching suitable filtration controlling additives for drilling fluids in the future.
研究领域:
材料科学
·
石油工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
·
IF 3.8
Jinxin Gan,Lekai Zhao,Jiesong Tan,Yiqing Zeng,Jiangxiao Qiao,Jiahao Chen,Zhaoxiang Zhong,Weihong Xing
High-temperature filtration is an energy-saving and efficient technology for treating high-temperature dusty exhaust, while most of the current studies focus on the design and preparation of high-temperature filtration materials and their application in room-temperature filtration. In this work, SiC ceramic membranes were prepared as typical high-temperature filtration materials to systematically investigate the high-temperature filtration process at 25–400 °C. The experimental results show that the filtration temperature has a significant effect on both initial filtration and cake filtration processes. The increase of temperature results in an increase of gas viscosity, which contributes to the increase of the initial filtration pressure drop (ΔP0). Meanwhile, temperature can affect the forces on dust in the pore of the SiC membrane, and a higher temperature leads to the easy penetration of dust (especially for the ultrafine particles) through the membrane layer into the support body layer at the initial filtration process. Moreover, the higher temperature can reduce the porosity of the dust cake, leading to an increase in the cake pressure drop (ΔPc). All above results were further proved during the experiments on studying the effect of the filtration velocity, dust concentration, and regeneration on the filtration performance of SiC membranes at 25 and 300 °C. Through this work, we expect to shed some light on the design and preparation of high-temperature filtration materials and on the understanding of the high-temperature filtration process.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2022
·
IF 8.943
Xuesong Ye,Zhencheng Ge,Qiliang Xiao,Bohan Liu,Meng Chen,Fangmin Wu,Jun Nan
In remote areas, low-pressure ultrafiltration membrane (LPM) systems can be applied in decentralized water supplies for the treatment of groundwater containing Fe 2+ , Mn 2+ , and NH 4 + . However, improving the performance of the LPM systems, such as the stable flux and removal capacity, presents a challenge. In this study, a novel opposite-flow low-pressure ultrafiltration membrane (O-LPM) system was applied, and its performance was evaluated. Experimental results showed that after 46 days of operation, the steady flux of the O-LPM systems were 1.87-fold and 1.74-fold higher than that of the conventional D-LPM systems under Mn 2+ concentration of 0.3 mg L −1 and 1.5 mg L −1 , respectively. With a mixed pollutant system containing Fe 2+ (0.5 mg L −1 ), Mn 2+ (0.3 mg L −1 ), and NH 4 + (1.0 mg L −1 ), the O-LPM-ripening period for Mn 2+ removal was shortened from 16 days to 8 days, and the NH 4 + removal efficiency was increased from 61.46% to 80.97%. The bio-cake layer in the O-LPM systems was thinner and had a higher uniformity than in the D-LPM systems, resulting in a larger stable flux range. The relative abundance of functional bacteria (MnOB, IOB, and NOB) was generally higher in O-LPM systems than in the D-LPM systems. Overall, these results are of high relevance for groundwater treatment in remote areas, providing guidance for the widespread application of the O-LPM system in decentralized water supplies.
研究领域:
环境工程
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Processes
·
2024
·Vol. 12
·期 12
·2738
·
IF 2.8
Ruxia Chen,Xianshu Dong,Zeyu Feng,Yuping Fan,Xiaomin Ma
Effective coal slurry water solid–liquid separation is indispensable for the recycling and sustainable development of coal resources. The interaction between bubble and coal particles plays a critical role in the process of dewatering for clean coal. In this study, we firstly conducted a comprehensive investigation of the impact of froth on the interactions between coal particles by rheological measurement and particle aggregation behavior. Furthermore, the macroscopic dewatering performance of coal slurry in the presence of froth and its microscopic cake structure were investigated using the filtration test and X-ray microtomography (CT). It was found that the interaction between coal particles in the presence of froth was enhanced as a result of the dynamic shear value, combined with the large floc size and compact structure, which led to a higher cake moisture and higher filtration velocity. The CT results indicated that the enhanced interaction of particles in the presence of froth also led to a dense microstructure of the filter cake. The porosity of the filter cake decreased to 2.05% when the aeration time increased from 0 s to 90 s, the throat radius in the filter cake was reduced to 1.32 μm, and the number of throat passages was reduced to one third. Multiple blind pores and low coordination numbers led to a poor connectivity of the pore network and high moisture content.
研究领域:
矿业工程
·
材料科学与工程
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Aosheng Yang,Yinfei Liao,Maoyan An,Yijun Cao,Zhe Yang,Hourui Ren,Hailong Su,Qiqi Zou,Luojian Chen
Filter aids are widely used in low-rank coal (LRC) slime filtration. However, their impact on filter cake characteristics is still unclear. In this paper, the effect of anionic polyacrylamide (APAM) and cetyltrimethylammonium bromide (CTAB) on the filter cake characteristics was investigated using Darcy’s filtration theory and low-field nuclear magnetic resonance (L-F NMR). The slime and filtrate property change was determined by contact angle, XPS, FBRM, Zeta potential and surface tension measurements. The results showed that the filter aid improved slime filtration rate and reduced filter cake moisture. The filter aid effect of APAM was better than that of CTAB . CTAB significantly improved the slime surface hydrophobicity with the contact angle increasing to 90.5°, and reduced the filtrate surface tension to 35.26 mN/m. However, APAM decreased the absolute value of slime Zeta potential by 7.48 mV, and increased the slime floc size by about 7–9 µm. Both CTAB and APAM can reduce the filtration resistance, but the effect of APAM was better than that of CTAB, because APAM greatly improved the filter cake permeability. L-F NMR results showed that CTAB increased the filter cake porosity only by 2.65%, while APAM significantly improved the filter cake porosity by 11.65%, especially the mesopore porosity of cake, which increased by 10.48%. It was indicated that CTAB reduced the filtration resistance by “lubricating” the pore wall of the filter cake, while APAM improved the filter cake porosity and permeability by weakening the electrostatic repulsion between slime particles and promoting floc formation through aggregation effect. This research provided a new perspective to reveal the mechanism of LRC slime filtration.
研究领域:
矿物加工工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2019
·Vol. 136
·期 38
·47965
·
IF 2.188
Wuge Cui,Guancheng Jiang,Yinbo He
Water-based drilling fluids always suffer from high-salt and high-temperature conditions, which cause safety andeconomic problems. Amphoteric copolymers are expected to solve this, although the underlying factors are still controversial. In this study, the AST (an amphoteric copolymer which was synthesized from 2-acrylamide-2-methyl propane sulfonicacid, (3-acrylamidopropyl)trimethyl ammonium chloride and acrylamide) was used as fluid loss additive, kaolinite (KT) was used as an evaluation condition, and a sandwich structure was found on the cross section of the filter cake. Four potential mainstream explanations were analyzed: the polymer properties, rheological behavior, dispersion of platelets, and structure of the filter cake. The sandwich structures in the cross section of filter cake were finally found and were confirmed by energy-dispersive spectroscopy. The sandwich structure, which consisted of an amphoteric polymer and a clay platelet, affected the fluid loss dramatically. This method for studying the cross section of the filter cake on the basis of KT evaluation could be used to investigate the filtration process of other fluid loss additives. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 47965.
研究领域:
材料科学
·
石油工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Xiaomin Ma,Pengcheng Wen,Yuping Fan,Xianshu Dong,Maoqing Yang,Yuanpeng Fu
The objective of this study was to elucidate the synergistic dewatering mechanism of mixed sodium dodecylbenzene sulfonate (SDBS) and polyethyleneimine (PEI) on kaolinite filter cakes and to test the dewatering effectiveness of a custom-built pressure dewatering device. The dewatering experiments showed that while the reagent dose was reduced by 50%, the dewatering rate decreased to 19.78%, surpassing the optimal dose of a single reagent. During the natural compression stage of the filter cake, the deformation reached its maximum under the same pressure difference. During the transitional period, the closure of the filter cake pores occurred at a slower rate, facilitating better moisture drainage. Under strong compression, the ultimate deformation reached its maximum. PEI acted as a bridging agent for kaolin flocculation and served as a medium for SDBS on the kaolin surface. A small amount of PEI reduced the electrostatic repulsion of SDBS, increasing its adsorption capacity. PEI adsorbed on the kaolin surface through electrostatic and hydrogen bonding, while SDBS could adsorb onto the PEI reagent layer through electrostatic and polar interactions, exposing its alkyl chains on the surface and thereby facilitating flocculation and generating a hydrophobic reagent layer. This study could provide a new method and insights for the efficient pressurized dewatering of kaolin.
研究领域:
环境科学
·
矿物加工工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）