December 21, 2015

Roads that De-Ice themselves

As winter approaches, shops, cities and householders are stocking up on salt, gravel and sand in anticipation of slippery roads. However this annual ritual in colder climates might quickly grow to be pointless. Researchers report in ACS’ journal Industrial & Engineering Chemistry Analysis a brand new street materials that would de-ice itself.

Each winter, when climate forecasters predict snow or icy circumstances, native governments deploy vans that mud roads with salt, or different chemical mixtures to assist forestall ice build-up. Residents escape their very own provide to maintain their walkways and driveways from freezing over and turning into dangerously slick.

However the de-icer does not keep on the streets for lengthy. Melting snow and automobiles driving by wash or pressure it off, making re-application crucial. To interrupt this cycle, Seda Kizilel and colleagues needed to see if they might devise a method to ice-proof the street itself.

The researchers began with the salt potassium formate and mixed it with the polymer styrene-butadiene-styrene. They added this combination to bitumen, a serious element of asphalt.

The ensuing materials was simply as sturdy as unmodified bitumen, and it considerably delayed ice formation in lab research. The brand new composite launched de-icing salt for 2 months within the lab, however the results might final even longer when used on actual roads, the researchers observe.

In that occasion, the salt-polymer composite can be evenly embedded all through the asphalt. Thus, as automobiles and vans drive over and put on away the pavement, the salt might regularly be launched—probably for years.

Extra info: Derya Aydın et al. Gelation-Stabilized Useful Composite-Modified Bitumen for Anti-icing Functions, Industrial & Engineering Chemistry Analysis (2015).

Summary
Ionic salts as anti-icing brokers have been extensively used to get rid of accumulation of ice on asphalt surfaces. Nevertheless, salt may be simply eliminated by rain or cars and requires frequent software on roads.

Apart from this financial consideration, anti-icing brokers compromise the mechanical properties of asphalt and have a adverse influence on dwelling organisms and the setting when utilized in giant quantities.

Incorporation of hydrophilic salts into bitumen, a hydrophobic asphalt binder, and managed launch of particular molecules from this hydrophobic medium can present an efficient answer for decreasing ice formation on pavements.

Bitumen has beforehand been modified by numerous polymers, together with styrene-butadiene-styrene (SBS) for improved power and thermomechanical properties. Nevertheless, an anti-icing perform was not thought-about in these earlier designs. In a earlier research, we developed a useful polymer composite consisting of potassium formate (HCOOK) salt pockets dissolved in a hydrophilic gel medium and dispersed in a hydrophobic SBS polymer matrix.

Right here, we developed an revolutionary technique to acquire polymer composite-modified bitumen and investigated additional the anti-icing properties of the practical bitumen. We improved incorporation of this polymer composite into bitumen and demonstrated correct distribution of the composite inside bitumen by means of morphological and rheological evaluation.

We characterised the anti-icing properties of modified bitumen surfaces and demonstrated vital will increase in freezing delay of composite-modified bitumen in comparison with base bitumen in a temperature- and humidity-controlled chamber. As well as, we characterised the discharge of HCOOK salt from polymer composite-modified bitumen and noticed salt launch inside the vary of 1.07–10.eight% (w/w) in 67 days, relying on the composite content material. The outcomes show the potential of this polymer composite-modified bitumen for anti-icing performance and for industrially related purposes.

Source- Sunnews Journal

December 15, 2015

Heavy Crude Spill Study

Refugio Rupture Informs Heavy Crude Spill Study
Environmental Consequence of Diluted Bitumen Spills Analyzed

A new study states that diluted bitumen, a raw material used as a feedstock in oil refineries, turns into a “heavy, viscous, particle-laden residue” after days of exposure, say, in ocean water after an incident like the Refugio Oil Spill.

That’s not unlike the type of oil found on the beach and in the water by the people who attempted to restore the shore this past May.

The heavy crude that befouled Refugio may not literally be diluted bitumen, explained UCSB geochemist David Valentine, but it has characteristics that are more like diluted bitumen than the lighter oils to which current spill response is tailored.

For instance, heavy crude tends to sink instead of float on the surface, and it is very sticky. Valentine is among the authors of the paper and also a scientist researching the aftermath of Refugio, which gave a first-hand case study of spill response.

The environmental risks of crude oil transport have been recognized since Santa Barbara’s blowout in 1969, the study says, and the 2010 bitumen spill into Michigan’s Kalamazoo River, among others, caused the Department of Transportation (DOT) to ask scientists if the potential environmental consequences of a bitumen spill were significantly different from a spill of “light” or “medium” crude.

Often extracted from tar sands, bitumen is too viscous to flow readily through pipelines, and oil producers commonly dilute it with lighter oils or condensed natural gas for pipeline transport. The study, titled “Spills of Diluted Bitumen from Pipelines:

A Comparative Study of Environmental Fate, Effects, and Response,” explains that “weathering” causes rapid physical and chemical changes to diluted bitumen after a spill, making it stickier and more dense than water.

The heavy crude from Canadian tar sands is commonly diluted, and the study lays out the Keystone pipeline proposal to move crude from Canada and other existing and proposed pipelines around the nation. (Though the study states the majority of California’s crude is moved through heated pipes, in Santa Barbara County, the main transport pipelines are insulated, not heated, and carry oil that has been heated and blended with natural gas liquids, according to the county’s Energy Division.)

The report, prepared for the DOT and published by the National Academies of Sciences, Engineering, and Medicine, also states its findings translate to transport such as truck and rail.

“Although many differences between diluted bitumen and other crude oils are well established, some remaining areas of uncertainty hamper effective responses to spills,” said Valentine, a professor of microbial geochemistry in the Department of Earth Science, in a UCSB press release.

“Further research is needed in a range of areas, including the ecological and human health risks posed by weathered diluted bitumen, techniques to capture submerged oil in moving water, and the application of advanced chemical approaches to understand the compositional changes to diluted bitumen in the environment.”

Given the new information about diluted bitumen, the report makes recommendations that the Coast Guard reclassify the substance as a nonfloating oil and that the National Oceanic and Atmospheric Administration (NOAA) create a database to predict possible locations of future bitumen spills.

It further advises the Pipeline and Hazardous Materials Safety Administration (PHMSA), which is a branch of the DOT, to modify transport rules to recognize the special hazards presented by diluted bitumen.

Source- The Independent