Novel technology for improving the treatability of turbidizing substances by coagulation and sedimentation

Treatability in the coagulation and sedimentation of turbidizing substances varies greatly depending on the rapid stirring strength GR. It is demonstrated that when PACl coagulant is used, the optimum treatability is achieved at GR values of 450 for turbidity and 1,000 sec−1 for STR, a newly introduced evaluation parameter. These values are much higher than the values typical of many water purification plants where the GR values are set at 100~200 sec−1. The remarkable improvement of coagulation and sedimentation treatment is found to be related to the formation of denser, smaller-diameter microfloc with increasing GR, and an increase in the incorporation of coagulant-derived aluminium in the microfloc and zeta-potential of the microfloc, among other flock properties.

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Research on the Microfluidics Control Method Based on the EOF Technology

Materials Science Forum ◽

10.4028/www.scientific.net/msf.532-533.65 ◽

2006 ◽

Vol 532-533 ◽

pp. 65-68

Author(s):

Hong Yuan Jiang ◽

Hu Kun Yang ◽

Yang Wang ◽

Tao Jiang

Keyword(s):

Mathematical Model ◽

Drug Delivery ◽

Zeta Potential ◽

Electric Field ◽

Drug Delivery Systems ◽

Control Method ◽

Novel Technology ◽

Micro Total Analysis Systems ◽

Total Analysis ◽

The Relationship

Electroosmoticflow (EOF) applied in micropump is a novel technology, which will be widely applied in micro total analysis systems (μTAS) and drug delivery systems. EOF velocity in microchannel depends on the zeta potential (ζ), the electric field (E) parallel to the microchannel and so on. Electric field can be decreased if ζ can be increased, which can reduce the disadvantage caused by the high electric field voltage. This paper discusses the relationship between EOF velocity and ζ, E, to realize this concept. Through building mathematical model, this paper analyzes the effects of changing ζ and E on EOF velocity, which provides the microfluidics control theory basis to design EOF micropump and presents a new subject of manufacturing micropump process.

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Laser Smoothing of the Load/Unload Tabs of Magnetic Recording Head Gimbal Assemblies

Journal of Tribology ◽

10.1115/1.1467640 ◽

2002 ◽

Vol 124 (4) ◽

pp. 863-865 ◽

Cited By ~ 5

Author(s):

Gurinder P. Singh ◽

Mike Suk ◽

Thomas R. Albrecht and ◽

William T. Kozlovsky

Keyword(s):

Surface Layer ◽

Pulse Length ◽

Sharp Decrease ◽

Disk Drives ◽

Recording Head ◽

Remarkable Improvement ◽

Novel Technology ◽

Laser Pulse Length ◽

Wear Tests ◽

Pulsed Laser Beam

A novel technology to smooth the metal tab surfaces using a pulsed laser beam is applied to reduce the wear of the load/unload ramps used in disk drives that employ load/unload technology. The laser pulse length, pulse energy and the pulse repetition rate are so chosen that they cause the surface layer of the load/unload tab, approximately 2–3 um deep, to melt and refreeze quickly. As the surface layer melts, the surface tension of the melt removes most of the micro roughness and a smooth surface is obtained. The reduction in the micro surface roughness is confirmed by the AFM traces and a sharp decrease in the light scattered from the tab surface. In wear tests, such tabs show a remarkable improvement in the wear of the plastic load/unload ramps, allowing 5–10 × more load/unload cycles for a given amount of ramp wear.

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Nanobiohybrid: A Favorite Candidate for Future Water Purification Technology

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1131.193 ◽

2015 ◽

Vol 1131 ◽

pp. 193-197 ◽

Cited By ~ 3

Author(s):

Rasel Das ◽

Sharifah Bee Abd Hamid ◽

Md Eaqub Ali

Keyword(s):

Water Purification ◽

One Pot ◽

Water Contaminants ◽

Diverse Range ◽

Safe Water ◽

Multi Scale ◽

Novel Technology ◽

Current Water ◽

Judicious Choice ◽

The Many

Clean and safe water crises have become one of the major global problems for decades. To address this issue, various water purification technologies have been adopted. Conventional water purification technologies are time consuming, expensive, and have low affinity and efficiency to newly emerging micropollutants in water. The paradigm might compel scientific community to spot light on the issue and develop novel technology for ensuring clean and safe water availability to all. Among the many promises of current water purification technologies, here we proposed a combination of nanomaterial (Carbon nanotube) and biomolecule (Enzyme) or simply “nanobiohybrid” catalyst, which can be a judicious choice for developing a novel water purification technology. In addition, the potentiality of this nanobiohybrid catalyst in both sensing and mitigating organic water pollutants has been highlighted. The technology is a perfect example of multi-scale development and covers most of the challenges of existing water purification technology. We hope this “one pot” combination route can tackle a diverse range of water contaminants in the near future.

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The combination of KMnO4 with HMO for cycles adsorption of heavy metal ions and regeneration of adsorbents

Water Science & Technology ◽

10.2166/wst.2021.108 ◽

2021 ◽

Author(s):

Ruyue Ding ◽

Chao Liu ◽

Fencun Xie

Keyword(s):

Heavy Metal ◽

Zeta Potential ◽

Metal Ions ◽

Manganese Dioxide ◽

Water Purification ◽

Heavy Metal Ions ◽

Competitive Adsorption ◽

Removal Rate ◽

Highly Active

Abstract In this experiment: three kinds of hydrous manganese dioxide (HMO) with different Zeta potential were synthesized, and combined with KMnO4 for deep removal of Pb2+, Cd2+ and Ni2+. The competitive adsorption of three heavy metal ions was also investigated. The results indicated that the stronger the acidity, the higher the Zeta potential (-54.3) of the synthesized HMO. After regenerating HMO with acidic KMnO4 as eluent, the removal rates of Pb2+, Cd2+ and Ni2+ could still reach 79.25%, 80.13% and 60.43% after five cycles of adsorption. The promoting mechanism of KMnO4's effect on HMO was analyzed by SEM, TEM, EDS, FTIR, XRD, XPS, BET, UV-vis. After absorbing of heavy metal ions, HMO will release part of Mn (II), and the released Mn (II) reacts with KMnO4 to form a small amount of highly active in-situ HMO. ‘HMO + KMnO4’ system can not only improve the removal rate of heavy metal ions by HMO, reduce the amount of adsorbent, but also remove the released Mn (II). Because of its reproducibility, efficiency and simplicity, the research on water purification materials and technologies is of significance.

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The impact of zeta potential changes on Ceratium hirundinella cell removal and the ability of cells to restore its natural surface charge during drinking water purification

RSC Advances ◽

10.1039/c7ra01185g ◽

2017 ◽

Vol 7 (36) ◽

pp. 22433-22440 ◽

Cited By ~ 1

Author(s):

H. Ewerts ◽

S. Barnard ◽

A. Swanepoel

Keyword(s):

Drinking Water ◽

Zeta Potential ◽

Surface Charge ◽

Water Purification ◽

Settling Time ◽

Organic Polymer ◽

Source Water ◽

Ceratium Hirundinella ◽

Drinking Water Purification ◽

The Impact

The removal efficacy ofCeratiumcells from source water was evaluated. The best ZP for coagulation were achieved with organic polymer and Ca(OH)2. Cells were able to restore their ZP after 120 and 240 minutes settling time.

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Sound cleans up water purification

Nature ◽

10.1038/news020413-4 ◽

2002 ◽

Author(s):

Ingrid Holmes

Keyword(s):

Water Purification

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How to use alum with cationic dispersed rosin size

TAPPI Journal ◽

10.32964/tj15.5.331 ◽

2016 ◽

Vol 15 (5) ◽

pp. 331-335 ◽

Cited By ~ 3

Author(s):

LEBO XU ◽

JEREMY MYERS ◽

PETER HART

Keyword(s):

Zeta Potential ◽

Colloidal Particles ◽

Streaming Potential ◽

Excessive Amount ◽

Paper Machine ◽

Optimum Amount ◽

Potential Measurement ◽

Streaming Current ◽

Wide Range ◽

Laboratory Results

Retention of cationic dispersed rosin size was studied via turbidity measurements on stock filtrate with different alum and dispersed rosin size dosages. Stock charge characteristics were analyzed using both an analysis of charge demand determined via a streaming current detector and an evaluation of zeta potential of the fibers by streaming potential measurement. The results indicated that an optimum amount of alum existed such that good sizing retention was maintained throughout a wide range of dispersed rosin size dosages. However, when an excessive amount of alum was used and fines and colloidal particles were transitioned from anionic to cationic, the cationic size retention was reduced. Laboratory results were confirmed with a paper machine trial. All data suggested that a stock charge study was necessary to identify optimal alum dosage for a cationic dispersed rosin sizing program.

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An Experimental Investigation on Thermal Conductivity and Viscosity of Graphene doped CNTs /TiO2 Nanofluid

International Journal of Automotive and Mechanical Engineering ◽

10.15282/ijame.17.3.2020.16.0620 ◽

2020 ◽

Vol 17 (3) ◽

Author(s):

A.M. Zetty Akhtar ◽

M.M. Rahman ◽

K. Kadirgama ◽

M.A. Maleque

Keyword(s):

Thermal Conductivity ◽

Zeta Potential ◽

Base Fluid ◽

Minimum Quantity Lubrication ◽

Cutting Fluid ◽

Cutting Zone ◽

Observation Method ◽

The Stability ◽

The Relationship ◽

Zeta Potential Analysis

This paper presents the findings of the stability, thermal conductivity and viscosity of CNTs (doped with 10 wt% graphene)- TiO2 hybrid nanofluids under various concentrations. While the usage of cutting fluid in machining operation is necessary for removing the heat generated at the cutting zone, the excessive use of it could lead to environmental and health issue to the operators. Therefore, the minimum quantity lubrication (MQL) to replace the conventional flooding was introduced. The MQL method minimises the usage of cutting fluid as a step to achieve a cleaner environment and sustainable machining. However, the low thermal conductivity of the base fluid in the MQL system caused the insufficient removal of heat generated in the cutting zone. Addition of nanoparticles to the base fluid was then introduced to enhance the performance of cutting fluids. The ethylene glycol used as the base fluid, titanium dioxide (TiO2) and carbon nanotubes (CNTs) nanoparticle mixed to produce nanofluids with concentrations of 0.02 to 0.1 wt.% with an interval of 0.02 wt%. The mixing ratio of TiO2: CNTs was 90:10 and ratio of SDBS (surfactant): CNTs was 10:1. The stability of nanofluid checked using observation method and zeta potential analysis. The thermal conductivity and viscosity of suspension were measured at a temperature range between 30˚C to 70˚C (with increment of 10˚C) to determine the relationship between concentration and temperature on nanofluid’s thermal physical properties. Based on the results obtained, zeta potential value for nanofluid range from -50 to -70 mV indicates a good stability of the suspension. Thermal conductivity of nanofluid increases as an increase of temperature and enhancement ratio is within the range of 1.51 to 4.53 compared to the base fluid. Meanwhile, the viscosity of nanofluid shows decrements with an increase of the temperature remarks significant advantage in pumping power. The developed nanofluid in this study found to be stable with enhanced thermal conductivity and decrease in viscosity, which at once make it possible to be use as nanolubricant in machining operation.

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