Berlin: Der große Klima-Aktionstag - 21. September 2014

Avaaz.org
Am 21. September 2014 weltweiter Klima-Aktionstag.
unser Beitrag, dies zur größten Bürgermobilisierung zu machen, die es je fürs Klima gegeben hat.

Quick Cook Method Turns Algae into Oil :: NASA Tech Briefs

Quick Cook Method Turns Algae into Oil :: NASA Tech Briefs

' Michigan Engineering researchers can "pressure-cook" algae for as little as a minute and transform an unprecedented 65 percent of the green slime into biocrude. "We're trying to mimic the process in nature that forms crude oil with marine organisms,"

Characterization of magnetic nanodispersions by multisample analytical centrifugation, DLS and electrokinetic potential - Partec 2013

Characterization of magnetic nanodispersions by multisample analytical centrifugation, DLS and electrokinetic potential  

magnetic nanodispersions - Partec 2013 

Multisample analytical centrifugation with high resolution photometric detection was applied to characterize the quality of differently stabilized magnetic nanodispersions. Results were compared with hydrodynamic size and zeta potential obtained by dynamic light scattering technique. Comparison of the ‘fingerprints’ gives a fast overview over differences in quality of magnetic nanodispersions (quality of particle stabilization against aggregation and separation stability). Sedimentation kinetics and distribution of sedimentation velocities allow for a more detailed quantitative comparison and ranking between different products and batches. The velocity distribution, which does not require any material properties to be known, can be used as an integral measure of separation stability. The magnetic nanodispersions are highly stable; separation at higher centrifugal acceleration is reversible when acceleration is lowered. This effect is enhanced in case of electrostatic repulsion between particles.

PARTEC 
Topic 3: Characterisation of the properties of particles, including size, shape, surface area, pore structure and strength of particles and agglomerates


24 April 2013  Room Tokio 11.00

Breaking the silence - Israeli veteran soldiers experience

Very impressive introduction given by a veteran Israeli solder about experience in occupied territories. Introduction to the exhibition given in English.

Watch introduction

LUM at World Filtration Congress WFC 11

11th World Filtration Congress in GRAZ, AUSTRIA, APRIL 16-20, 2012

LUM will present at the exhibition

Booth G5

and give 4 presentations on different topics

Accelerated screening by multisample analytical centrifugation for selection of flocculants and demulsifiers

T. Sobisch*, D. Lerche

LUM GmbH, Berlin / Germany info@lum-gmbh.de, www.lum-gmbh.com

Selection of flocculants and demulsifiers is a frequent challenge. It relates to remedy of settling issues and to the optimization of separation processes in fields like wastewater treatment and crude oil processing.

Multisample analytical centrifugation based on STEP-Technology offers a unique option for screening for the optimal product, additive concentration and separation conditions. Not only the degree of separation but also separation kinetics and the residual turbidity can be determined with high throughput by comparison of 12 samples under identical conditions in 1 run.

The potential of this approach is demonstrated by case studies for the selection of flocculants for centrifugal dewatering of wastewater sludges and for selection of optimum demulsifier selection for crude oil dewatering.

Keywords: additive screening, flocculant selection, demulsifier selection, dewatering efficiency, separation velocity, analytical centrifugation

Measurement of x ray profiles – a new method for the evaluation of separation behaviour of concentrated nontransparent dispersions

A. Zierau*, A. Fedur, T. Sobisch, D. Lerche

LUM GmbH, Berlin / Germany i

Detailed evaluation of the separation behaviour of dispersion is problematic for concentrated nontransparent dispersions. It is difficult to define a separation level or to trace differences in solids concentration along the liquid column.

Measurement of space and time resolved x ray transmission profiles offers a unique solution to this problem. This approach can even be used to determine concentration gradients in sediments, which is of great importance for separation unit processes like filtration, settling and centrifugation. Even more information about the structure of sediments can be used to deduce the nature of particle interactions and to determine the degree of flocculation.

The method can be applied to determine the kinetics of separation processes or to determine the concentration distribution obtained after separation, i.e. after settling, centrifugation, filtration.

The measurement technique and its application for different systems like mineral suspensions and emulsions is introduced.

Keywords: x-ray, dispersion structure, suspensions, emulsions, separation analysis, sediment profiles

Separation and consolidation behaviour of flocculated versus non-flocculated dispersions: A reliable laboratory classification test

T.Sobisch, A. Zierau, D.Lerche*

LUM GmbH, Berlin/Germany

Flocculation behaviour is important in many technical applications and especially in solid-liquid separation. While for some applications sedimentation and consolidation have to be avoided or minimized, for solid-liquid separation these are essential. Often the value of Zeta-potential is employed to judge the state in the sense of flocculated versus non-flocculated dispersions. But this approach is often not applicable especially in case of sterically or rheologically stabilized dispersion. There is a need for fast reliable methods for comprehensive characterization of flocculation processes.

Analytical centrifugation based on Space and Time resolved detection of Extinction Profiles of electromagnetic waves (STEP-Technology) over the entire sample height was used to characterize the nature of particle interactions and the degree of flocculation in dispersions at original concentration. Photometric and x-ray measurements were carried out.

Investigations on sedimentation and consolidation behaviour of flocculated polydisperse suspensions of different suspensions made from quartz, lime stone, titanium oxide, magnetic therapeutic carrier particles and enzyme coated nanoparticles are presented to demonstrate the procedure. Colloidal stable dispersions (stable against flocculation, agglutination) show typical polydisperse sedimentation behaviour, whereas flocculated dispersions exhibit zone sedimentation and gradual consolidation. While the packing density for colloidal stable dispersions does depend only slightly on the excess pressure acting on the sediment it strongly depends on pressure for flocculated dispersions and it takes much longer to reach corresponding equilibrium packing density. Instead of carrying out measurements at different accelerations it is also possible to evaluate the compressibility of sediments (or cream layers) by increasing the acceleration step-wise and recording the kinetics of the sediment (cream layer) height or packing sediment concentration. It was shown that in all investigated suspensions the state of flocculation was correctly classified even at very high concentration but e.g. in case of polymer stabilized magnetic micro- and nano-particles high Zeta-potential (40 - 60 mV) would lead to false “non-flocculated” classification.

Keywords: flocculation state, analytical centrifugation, Zeta-potential, coated nanoparticles, compressibility, sediment density, emulsions, suspensions, sedimentation, creaming

Is it possible to reduce costs for pilot centrifuge testing by lab scale tests?

T. Detloff*, S. Küchler, T. Sobisch, D. Lerche

LUM GmbH, Berlin / Germany

Unit processes using centrifugal fields are often applied for separation and classification of diverse materials. Modelling of these processes requires information about the separation behaviour of the suspensions to be processed. To this end direct measurements in centrifuges are obligatory for the dimensioning of the separation units to obtain the desired cut-off size and residual effluent turbidity. Moreover, these measurements have to gather kinetic information as function of the processing conditions, viscosity behaviour, particle interaction and particle concentration of the product. Results of measurements at earth gravity cannot be scaled up to reflect the situation in a centrifugal field.

A multisample analytical centrifugation technique with photometric detection is presented which allows a comprehensive characterization of separation processes in the centrifugal field at lab scale with high sample throughput. In particular the type of sedimentation behaviour (free sedimentation of individual particles, hindered settling, zone settling) can be deduced from the progression of the transmission profiles. Even more it can determine the critical residence time as function of feed concentration for a desired effluent clarity and allows measuring the velocity distribution of particles inside the centrate in-situ.

Approaches for dimensioning the centrifugation at larger scale based on these in-situ at labscale available data are discussed.

Keywords: process optimization, solid-liquid separation, liquid-liquid separation, process design, decanter centrifuges, analytical centrifugation

Was gesagt werden muss - Günther Grass - an den Reaktionen sollt Ihr sie erkennen.

Was gesagt werden muss - Kultur - sueddeutsche.de

Kernsätze

'Es ist das behauptete Recht auf den Erstschlag,
der das von einem Maulhelden unterjochte
und zum organisierten Jubel gelenkte
iranische Volk auslöschen könnte, ...'

'Warum aber schwieg ich bislang?
Weil ich meinte, meine Herkunft,
die von nie zu tilgendem Makel behaftet ist,
verbiete, diese Tatsache als ausgesprochene Wahrheit
dem Land Israel, dem ich verbunden bin
und bleiben will, zuzumuten....'

'....zudem ist zu hoffen,
es mögen sich viele vom Schweigen befreien,
den Verursacher der erkennbaren Gefahr
zum Verzicht auf Gewalt auffordern und
gleichfalls darauf bestehen,
daß eine unbehinderte und permanente Kontrolle
des israelischen atomaren Potentials
und der iranischen Atomanlagen
durch eine internationale Instanz
von den Regierungen beider Länder zugelassen wird.
Nur so ist allen, den Israelis und Palästinensern,
mehr noch, allen Menschen, die in dieser
vom Wahn okkupierten Region
dicht bei dicht verfeindet leben
und letztlich auch uns zu helfen.'

Allgemeine Reaktion der politischen Klasse
'Antisemitismus', 'Hasspamphlet', 'Verirrung'

Erinnert mich an frühere Anforderungen an die sozialistische Persönlichkeit
Parteilichkeit, 'wem nützt es', klar Stellung beziehen, zu den Siegern der Geschichte gehören ...

Dogmen kann man auch nicht mit den besten Argumenten beikommen.

Insektenvernichtungsmittel künftig ein zunehmendes Problem für Gewässer in Europa - Helmholtz-Zentrum für Umweltforschung UFZ - Forschen für die Umwelt

Insektenvernichtungsmittel künftig ein zunehmendes Problem für Gewässer in Europa - Helmholtz-Zentrum für Umweltforschung UFZ - Forschen für die Umwelt

Zitate:
Europas Gewässer werden in Zukunft stärker mit Insektenvernichtungsmitteln belastet sein als bisher. Das ist das Ergebnis einer Studie des Helmholtz-Zentrums für Umweltforschung (UFZ)...

Die Wissenschaftler empfehlen deshalb, den Eintrag von Pflanzenschutzmitteln drastisch zu minimieren. Neben einer Verminderung des Pestizideinsatzes kann dies durch die Einrichtung von Pufferzonen am Gewässer erfolgen.


Lediglich für 12 Küstenstaaten der USA gibt es Schätzungen, die einen generellen Anstieg des Insektizideinsatzes im Zeitraum 2000 bis 2100 von bis zu 28 Prozent erwarten. Die europäische Studie dagegen rechnet mit einem wesentlichen höheren Anstieg von bis zum 23fachen des momentanen Insektizideinsatzes in einzelnen Ländern je nach Stärke des Temperaturanstiegs und der zugrunde gelegten Landnutzungsänderung.
 

Außer Begrenzung der Auswirkungen durch Pufferzonen werden keine Alternativen gefordert/diskutiert.

Eine Alternative wäre Stärkung der natürlichen Feinde der Schadinsekten.

Diethylhexyl phthalate (DEHP), bisphenol A, and pesticides Pollute European Water Bodies More Than Previously Thought

Diethylhexyl phthalate (DEHP), bisphenol A, and pesticides Pollute European Water Bodies More Than Previously Thought

Studie: Pestizide belasten Gewässer stärker als gedacht

SOURCE: Helmholtz Association of German Research Centres 

.....
One of the most frequently registered compounds was diethylhexyl phthalate (DEHP), a chemically-produced softener which may impair fertility and is therefore banned in the EU from 2015. This is followed by another softener bisphenol A (BPA), which may also impair fertility, and diclofenac and ibuprofen, two pharmaceutical substances used commonly in painkillers.
The scientists classified a total of 73 compounds as potential priority pollutants. Around two thirds of these are pesticides, i.e. products used in agriculture to protect crops against disease, pests and weeds.
....
"Terbuthylazine is a compound that is structurally closely related to the priority pollutants simazine and atrazine, which may not be applied any more. This is a nice example how small structural modifications of chemical products may apparently improve the chemical status without mitigating any hazards to the aquatic ecosystems."
....We were also surprised that substances previously classified as harmless, such as HHCB, which is used as a synthetic musk fragrance in personal care products, are present in the environment in alarming concentrations,"

less than five cents per person per day to provide clean drinking water

'Research confirmed cost of just pennies a day per person to provide safe drinking water; Independent, scientific research validates potable water solution and its impact in a developing country; Project Safewater-Colón findings can help address the United Nation's Millennium Development Goals'
Article on water.online 

see http://www.projectsafewater.com/

Wir.Dienen.Deutschland?

für Frieden und Demokratie in der Welt.

wie unsere Regierung mit Waffenlieferungen an Saudiarabien.

Saudiarabien ist unser Verbündeter

wie vormals Gaddafi.

Militär dient der Fortsetzung der Politik mit anderen Mitteln.

Dem dienen?

Wir.Dienen.Deutschland.

Wir.Dienen.Deutschland.

für den Frieden der Welt.

Da können dann auch mal paar kleine Afghanen drauf gehen.

'Deutschland muß auch seine wirtschaftlichen Interessen militärisch verteidigen'

Heil Dir im Siegerkranz fürs deutsche Vaterland sterben wir.



Alternative

Triclosan replacement

sensidin^® DO – a triclosan alternative for deodorants

Product offered by

Schülke&Mayr GmbH

Product description
sensidin® DO combines the well-known deodorant and skin care
properties of ethylhexylglycerin with the antimicrobial properties
of octenidine HCl.


see also industry urged to take precautions with triclosan

Industry urged to take precautions with triclosan

source cosmetics design-europe.com

By Andrew McDougall, 03-Dec-2010

Following various studies on the use of the antibacterial agent triclosan in consumer products, including oral care, experts are urging companies to remove it from their formulations as a precaution.

Elizabeth Salter Green, director of ChemTrust, a health and environmental body, explained that on a precautionary basis the chemical may not be safe to use at any level.

“It is important to stress that triclosan is not a dioxin, however concerns are that under certain circumstances it can develop the ability to disrupt hormones,” she told CosmeticsDesign-Europe.com.

Found in many consumer products

Triclosan is an ingredient added to many consumer products as an antibacterial ingredient.

It may be found in products such as antibacterial soaps and body washes, toothpastes, and some cosmetics. It is regulated by the U.S. Food and Drug Administration (FDA), and the European Union.

At this time, the FDA does not have evidence that triclosan added to antibacterial soaps and body washes provides extra health benefits over soap and water. However it stated that in 1997, reviewed extensive effectiveness data on triclosan in Colgate Total toothpaste showing that triclosan in this product was effective in preventing gingivitis.

Salter Green suggested that whilst one toxin may be harmless in a product individually, they may be dangerous if reacting together, suggesting that if there was no benefit for the toxin, it should be left out of the formulation.

Removed from GSK’s oral products

Oral care giant, GlaxoSmithKline, has removed triclosan from its Aquafresh and Sensodyne toothpastes, as well as its Corsodyl mouthwash, according to the University of Florida which has performed a study on the ingredient in sheep.

“If one eats the right foods and maintains correct dental hygiene, then triclosan, or other antibacterial agents are not needed,” explained Salter Green.

In the study by the University of Florida, researchers found that levels of triclosan were potentially damaging to the unborn foetus, if ingested by the carrying mother.

“We know it's a problem. But we just don't know how much of a problem. Triclosan can affect blood flow to the uterus, meaning the baby’s brain does not get the oxygen it needs,” said Professor Margaret James, who is the lead-author of the present study.

Discussing this particular study, Salter Green mentioned that a developing foetus in the uterus is extremely sensitive, and may be affected by disrupted hormone affecting brain development, metabolism, or the reproductive system.

Although this test was carried out on sheep, she explained that if the triclosan disrupts the hormone activity in an animal, whilst not being 100 per cent comparable, preserved hormonal evolution would suggest possible dangers to humans, and that the agent should be avoided if possible purely from a precautionary level.

comment

after wide spread use in sanitizers an increase in dioxine levels was experienced, leading to the conclusion that under some circumstances dioxines may be formed from triclosan.

FDA-fact sheet triclosan

What is triclosan?

Triclosan is an ingredient added to many consumer products to reduce or prevent bacterial contamination. It may be found in products such as clothing, kitchenware, furniture, and toys. It also may be added to antibacterial soaps and body washes, toothpastes, and some cosmetics—products regulated by the U.S. Food and Drug Administration (FDA).

What is known about the safety of triclosan?

Triclosan is not currently known to be hazardous to humans. But several scientific studies have come out since the last time FDA reviewed this ingredient that merit further review.

Animal studies have shown that triclosan alters hormone regulation. However, data showing effects in animals don’t always predict effects in humans. Other studies in bacteria have raised the possibility that triclosan contributes to making bacteria resistant to antibiotics.

In light of these studies, FDA is engaged in an ongoing scientific and regulatory review of this ingredient. FDA does not have sufficient safety evidence to recommend changing consumer use of products that contain triclosan at this time.

Does triclosan provide a benefit in consumer products?

For some consumer products, there is clear evidence that triclosan provides a benefit. In 1997, FDA reviewed extensive effectiveness data on triclosan in Colgate Total toothpaste. The evidence showed that triclosan in this product was effective in preventing gingivitis.

For other consumer products, FDA has not received evidence that the triclosan provides an extra benefit to health. At this time, the agency does not have evidence that triclosan in antibacterial soaps and body washes provides any benefit over washing with regular soap and water.

What consumers should know:

• Triclosan is not known to be hazardous to humans.
• FDA does not have sufficient safety evidence to recommend changing consumer use of products that contain triclosan at this time.
• In light of questions raised by recent animal studies of triclosan, FDA is reviewing all of the available evidence on this ingredient’s safety in consumer products. FDA will communicate the findings of its review to the public in spring 2011.
• At this time, FDA does not have evidence that triclosan added to antibacterial soaps and body washes provides extra health benefits over soap and water. Consumers concerned about using hand and body soaps with triclosan should wash with regular soap and water.
• Consumers can check product labels to find out whether products contain triclosan.

How can I tell if there is triclosan in a product that I am using?

Antibacterial soaps and body washes, and toothpastes are considered over-the-counter drugs. If an over-the-counter drug contains triclosan, it will be listed as an ingredient on the label, in the Drug Facts box. If a cosmetic contains triclosan, it will be included in the ingredient list on the product label.

What is FDA doing to evaluate the safety of triclosan?

We are engaged in an ongoing scientific and regulatory review of the safety of triclosan in FDA-regulated products. We also have partnered with other Federal Agencies to study the effects of this substance on animal and environmental health (see http://www.epa.gov/oppsrrd1/REDs/factsheets/triclosan_fs.htm; http://www.epa.gov/endo/).

FDA is working to incorporate the most up-to-date data and information into the regulations that govern the use of triclosan in consumer products. FDA will communicate the findings of its review to the public in spring 2011.

This article appears on FDA's Consumer Updates page, which features the latest on all FDA-regulated products.

Date Posted: April 8, 2010

new interest in surfactant enhanced soil clean-up

In the last years I only sporadically observed new abstracts on this topic.
In the latest issue of clu-in.org I found several of them. It seems interest in this topic is revitalizing.

the first is not associated with surfactants I think

ADVANCED METHODOLOGIES FOR THE TREATMENT OF HYDROCARBON CONTAMINATED SLUDGES FROM SOIL WASHING PROCESSES

Garcia Frutos, F.J., O. Escolano, R. Perez, A. Rubio, A. Gimeno, M.D. Fernandez, M. Babin, G. Carbonell, C. Perucha, and J. Laguna. First Spanish National Conference on Advances in Materials Recycling and Eco-Energy, Madrid, 12-13 November 2009. Paper S02-6, p 49-52, 2009

Fine products (silt-clay fractions) in sludge from soil washing plants following bulk soil treatment usually are highly contaminated. These fractions commonly are committed to landfill disposal or thermal destruction (in the case of organic contaminants). This paper presents the results of preliminary physical-chemical and bioremediation treatability tests carried out on a hydrocarbon-heavy sludge sample after bulk soil processing in a soil washing plant. To date, best results were obtained in two bioremediation processes tested at lab scale—landfarming and bioreactors—which decreased hydrocarbon levels by better than 50% in two months and one month, respectively. http://digital.csic.es/bitstream/10261/18607/1/S02_6.pdf

comment: reducing the very high contamination with spending time and money by only 50 % is really not worse the effort.

ULTRASOUND ASSISTED SOIL WASHING FOR REMOVAL OF DIESEL WITH SURFACTANT

Cho, S.-H., Y. Son, J. Cha, S.-G. Nam, M. Lim, and J. Khim, Korea Univ.
Proceedings of Symposium on Ultrasonic Electronics, Vol 30, p 147-148, 2009 [18-20 November 2009, Paper 1P4-31]

Mechanical mixing generally is a key process in conventional soil washing, sometimes accompanied by injection of anionic or non-ionic surfactants to enhance mass transfer of pollutants from soil to aqueous phase. Tests of the application of ultrasound to the washing process indicate a significant increase in removal efficiency. When the washing water or slurry was irradiated with ultrasound, cavitation events occurred, and sonochemical and sonophysical effects were induced. Sonophysical effects, such as micro jet and micro streaming, could enhance mass transfer of organic/inorganic pollutants from soil phase to aqueous phase. This paper describes the conduct and results of a study undertaken to compare an ultrasonic soil washing process with a conventional mechanical soil washing treatment to gain a better understanding of the mechanisms of each process. http://www.use-jp.org/USE2010/proceedings/USE09/pdf/1P4-31.pdf

TREATMENT OF FUEL-OIL CONTAMINATED SOILS BY BIODEGRADABLE SURFACTANT WASHING FOLLOWED BY FENTON-LIKE OXIDATION

Tsai, T.T. and C.M. Kao (National Sun Yat-Sen Univ., Taiwan); R.Y. Surampalli (U.S. EPA, Kansas City, KS); S. H. Liang (National Sun Yat-Sen Univ.).
Journal of Environmental Engineering, Vol 135 No 10, p 1015-1024, 2009

A bench-scale study was conducted to develop a two-stage remedial system consisting of surfactant washing followed by a Fenton-like oxidation process to remediate fuel-oil contaminated soils. The researchers also evaluated the effects of residual surfactant and soil organic matter (SOM) on the efficiency of Fenton-like oxidation; the effect of potassium dihydrogen phosphate (KH₂PO₄) addition on the stability of H₂O₂ and oxidation efficiency; and the possible oxidation products after the oxidation process. In the surfactant washing stage, a biodegradable surfactant, Simple Green (SG) at 50 g/L, was applied to flush fuel-oil contaminated soil having initial total petroleum hydrocarbons (TPHs) concentration of 50,000 mg/kg. Washing with 45 pore volumes (PVs) of SG followed by 25 PVs of deionized water achieved 90% TPH removal, dropping the soil TPH concentration from 50,000 to 4,950 mg/kg. In the Fenton-like oxidation stage at initial soil TPH concentration of ~4,950 mg/kg, TPH removal efficiency increased significantly with increased H₂O₂ concentrations. There was evidence that residual SG and SOM can compete with TPH for oxidants and thereby decrease oxidation efficiency; hence, an oxidation-sorption-desorption-oxidation scheme for soil TPH was observed in this experiment due to the initial sorption of TPH on SOM. Addition of 2.2 mM of KH₂PO₄ increased the stability and half-life of H₂O₂ but decreased TPH removal efficiency. The oxidation potential of the Fenton-like process was insufficient to oxidize fuel oil completely to nontoxic end products. The by-products observed after the oxidation process contained carboxyl groups with molecular weights similar to their parent compounds. Results indicate that the two-stage remedial system shows promise for future treatment of fuel-oil contaminated soil.

REMEDIATION OF DDT-CONTAMINATED SOIL USING OPTIMIZED MIXTURES OF SURFACTANTS AND A MIXING SYSTEM
Ghazali, M., E. McBean, H. Shen, W. Anderson, and P.-A. Dastous.
Remediation Journal, Vol 20 No 4, p 119-132, 2010

A surfactant-aided soil washing technique was studied as an alternative method for remediation of DDT-contaminated clayey soil. The ex situ process used both nonionic and anionic surfactants. A mixture of 1% nonionic surfactant (Brij 35) and 1% anionic surfactant (SDBS) removed more than 50% of DDT from soil in a flow-through system, whereas individual surfactants or other combinations of the surfactants exhibited lower removal efficiency. The use of a mixing system improved the soil washing process. A combination of 2% Brij 35 and 0.1% SDBS was found to be optimum, removing 70 to 80% of DDT. Prewashing the soil with tap water decreased the adsorption of surfactants to soil particles by 30 to 40%, and postwashing recovered 90% of the surfactants.

BENCH SCALE TREATABILITY STUDIES OF CONTAMINATED SOIL USING SOIL WASHING TECHNIQUE

Gupta, M.K., R.K. Srivastava, and A.K. Singh.
E-Journal of Chemistry, Vol 7 No 1, p 73-80, 2010

Surfactant washing is an ex situ process. The excavated contaminated soil can be heaped on plastic liners or other impermeable barriers and irrigated with washing solutions such as surfactant; alternatively, batch washing of the contaminated soil can be conducted in tanks or lined pits using continuous flows washing in countercurrent or normal modes. The authors applied soil washing using plain water enhanced with surfactants to a study of the remediation of soil contaminated with engine lubricant oil or a heavy metal. The engine oil was used at different percentages (by dry weight of the soil) to contaminate the soil artificially. The geotechnical properties of the soil underwent large modifications after mixing with the oil. Sorption experiments were conducted with cadmium metal in an aqueous medium at different initial concentrations of the metal and at varying pH values of the sorbing medium. For the remediation of contaminated soil matrices, a nonionic surfactant was used for the restoration of geotechnical properties of the soil samples contaminated with lubricant oil, while an anionic surfactant was employed to desorb cadmium from the contaminated soil matrix. The surfactant for soil contaminated with lubricant oil was able to restore properties up to 98% of those of virgin soil, while up to 54% cadmium was desorbed from the contaminated soil matrix in surfactant-aided desorption experiments. http://www.e-journals.in/PDF/V7N1/73-80.pdf

comment: As nonionic surfactant Triton X-100, as anionic Sodium Dodecyl Sulfate, selection seems to be based on scholarly aspects.
In my experience for mineral oil contaminated soil a mixture of anionic/nonionic works best, e.g. 3 parts Na Alkyl benzene sulfonate / 7 parts Synperonic 91/4


ELECTROKINETIC REMOVAL OF PETROLEUM HYDROCARBON FROM RESIDUAL CLAYEY SOIL FOLLOWING A WASHING PROCESS
Jeon, C.-S., J.-S. Yang, K.-J. Kim, and K. Baek.
CLEAN — Soil, Air, Water, Vol 38 No 2, Feb 2010

A study was conducted of total petroleum hydrocarbon (TPH) removal from residual clayey soil using an electrokinetic process following a washing procedure. Eight electrokinetic experiments were carried out to investigate the characteristics of TPH removal. When 0.1 M MgSO₄ or 0.1 M NaOH was used as an electrolyte, the electric current increased rapidly within the first 100 or 200 h, respectively. A negatively charged soil surface resulted in a more negative zeta potential and greater electroosmotic flow toward the cathode. The accumulated electroosmotic flow was higher when using 0.1 M NaOH as the anolyte-purging solution than when using 0.1 M MgSO₄. Although the energy consumption for the two purging solutions was similar, the efficiencies of TPH removal when 0.1 M MgSO₄ and 0.1 M NaOH with surfactant were used were 0 and 39, respectively, because the electroosmotic flow rate increased with TPH removal efficiency. When 5 isopropyl alcohol was used as a circulation solution, the electric current increased, but the TPH removal was similar to that using water. In terms of energy consumption, the use of a surfactant-enhanced electrokinetic process with NaOH as electrolyte was effective in removing TPHs from low-permeability soil. http://onlinelibrary.wiley.com/doi/10.1002/clen.200900190/pdf

REMOVAL OF HIGH CONCENTRATIONS OF POLYCYCLIC AROMATIC HYDROCARBONS FROM CONTAMINATED SOIL BY BIODIESEL
Jinbao Wu, Zongqiang Gong, Liyan Zheng, Yanli Yi, Jinghua Jin, Xiaojun Li and Peijun Li
Frontiers of Environmental Science & Engineering in China, [online prior to print publication] 2010
Solubilizing experiments were carried out to evaluate the ability of biodiesel to remove PAHs from highly contaminated manufactured gas plant (MGP) and PAH-spiked soils alongside applications of hydroxypropyl-beta-cyclodextrin (HPCD) and tween 80 as comparisons. Biodiesel displayed the highest solubilities for phenanthrene (420.7 mg/L), pyrene (541.0 mg/L), and benzo(a)pyrene (436.3 mg/L). These corresponded to several-fold increases relative to 10% HPCD and tween 80. Biodiesel showed a good efficiency for PAH removal from the spiked and MGP soils for both low- and high-molecular-weight PAHs at high concentrations. Biodiesel was a more effective agent for PAH removal from the spiked soils compared with HPCD and tween 80; it achieved over 77.9% removal of individual PAHs. Tween 80 also showed comparable capability with biodiesel for PAH solubilization at a concentration of 10% for the spiked soils. Biodiesel solubilized a wider range of PAHs than HPCD and tween 80 for the MPG soils. At PAH concentrations of 229.6 and 996.9 mg/kg, biodiesel removed >80% of total PAHs. The investigators observed a significant difference between PAH removals from the spiked and field MGP soils: PAH removals from the MGP soil by HPCD and tween 80 were much lower than those from the spiked soil. These results demonstrate the potential for utilizing biodiesel for remediation of highly PAH-contaminated soil.

comment: Though biodiesel worked best (I experienced the same), it works when used as 100 %. Clean-up of biodiesel for recycling proved difficult, with activated carbon it will be costly. For PAH extraction I would suggest a combination of about 1 part carboxymethyl cellulose / 9 Part Synperonic 91/4.

WASHING OF FIELD WEATHERED CRUDE OIL CONTAMINATED SOIL WITH AN ENVIRONMENTALLY COMPATIBLE SURFACTANT, ALKYL POLYGLUCOSIDE
Han, M., G. Ji, and J. Ni, Peking Univ., Beijing, China.
Chemosphere, Vol 76 No 5, p 579-86, 2009
Weathered crude oil-contaminated soils are much more difficult to remediate than those freshly contaminated. Although surfactant-enhanced ex situ soil washing can be used to remediate the weathered soils, surfactant toxicity is a major concern. A class of green surfactants, alkyl polyglucosides (APGs), was tested for washing field-weathered soils with relatively high oil concentration (123 mg/g dry soil) from an oilfield in China. APG1214, characterized with a longer alkyl chain, was more effective than APG0810 for removing crude oil. Addition of inorganic sodium salts to the APG1214 solution further improved crude oil removal efficiency. Washing parameters (temperature, washing time, agitation speed, and solution/soil ratio) were investigated, further optimized, and integrated with an orthogonal design. Under optimum conditions, removal efficiency reached 97%. GC/MS analysis showed that the proportion of small n-alkanes (C(16) to C(23)) in residual crude oil gradually increased, which helped to interpret the oil removal mechanism. Removal of large n-alkanes was achieved from the synergy between APG1214 and inorganic salts, which was the opposite of the effect when they were added separately. This study presents a promising technique for remediation of weathered crude oil-contaminated soils with ecologically compatible surfactant and provides guidelines for its practical application.

Asphaltene stability - nonscanning NIR technique: World Congress on Emulsion 2010

Contribution to the 5th world congress on emulsion CME
12 - 14 October, Lyon, France

A comparative study of asphaltene precipitation/flocculation by a new non-scanning NIR-technique in accordance with ASTM D 7061

St. Küchler, T. Sobisch, A. Uhl, D. Lerche

LUM

Rudower Chaussee 29 (OWZ) 12489 Berlin / Germany

info@lum-gmbh.de, www.lum-gmbh.com

Abstract

Asphaltenes and its derivatives, which are present in crude oil emulsions , may create severe technical and economical problems when they precipitate. Especially the flocculation of asphaltenes in heavy fuel oils may cause severe problems, including reservoir plugging, fouling of production facilities, altering wettability and poisoning refinary catalysts. Therefore the prediction and prevention of asphaltene flocculation is a crucial task for technical and laboratory staff in R&D, QC and production.

From the various methods that have been suggested over the years to serve this task the ASTM D 7061-05a has become an industrial standard to quantify and predict asphaltene flocculation in crude oils and heavy fuels.

In this contribution a non-scanning NIR-technique will be applied to measure asphaltene stability according to ASTM D 7061-05a by space and time resolved extinction (transmission) profiles (STEP-Technology). This apparatus (LUMiReader®, LUM GmbH) has the capability to measure simultaneously in 3 channels at tontrolled temperature up to 60°C.

Nine different crude oils with and without inhibitor were studied.

For direct comparison the same samples have been analyzed by the scanning apparatus described in the ASTM D 7061-05a.

The Separability Numbers, calculated from the measurements with the non-scanning NIR-apparatus, range from 0.2 to 15 showing a very good reproducibility and a very good agreement with the scanning technique. The applied non-scanning NIR-apparatus therefore is able to serve the broad spectra of crude oils in the market.

Keywords: Crude oil, heavy fuel oil, Induced Phase Separation of Asphaltene, Separability Number, STEP-Technology