are searching for an affordable process to turn salty wastewater into water
suitable for irrigation and drinking. One solution could be a new type of gas
hydrate desalination that removes more than 90% of salt from wastewater,
according to an American Chemical Society (ACS; Washington, D.C.) news release.
hydrate consists of water and a gas such as methane. When hydrates form, salts
and other impurities are left behind; and when hydrates break down, gas and
pure water are released. This method removes about 70% of salt from wastewater,
but forming gas hydrates for desalination requires the costly process of
cooling water down to 28°F.
Yongkoo Seol and Jong-Ho, both from the U.S. Department of Energy’s National
Energy Technology Laboratory, developed a less expensive version of this method
involving a variation on methane hydrates, chunks of ice retrieved from the
deep sea that burst into flame when brought to the surface, the news release
says. They formed hydrates from water and carbon dioxide with gases
cyclopentane and cyclohexane, improving efficiency of the method and removing
more salt than the previous gas hydrate technique.
this process can be performed near room temperature, the need for chilling is
reduced. The process could help purify highly salty water produced by hydraulic
fracturing, the news release says. The
research report, “Increasing Gas Hydrate Formation Temperature for Desalination
Salinity Produced Water With Secondary Guests,” appears in the journal ACS
Sustainable Chemistry & Engineering.
matting waterways across the country
weather and an increase in nonpoint source pollution are resulting in
widespread toxic algae outbreaks. A new online map released by Resource Media
(San Francisco) shows 21 states across the U.S. have issued health advisories
and warnings related to harmful algal blooms at 147 different locations on
lakes, rivers, and ponds during the summer. A new report provides a look at the
causes as well as the effects and costs of algae spreading across waterways,
according to a National Wildlife Federation (NWF; Reston, Va.) news release.
to the report, “Toxic Algae: Coming Soon to a Lake Near You?,” released by
Resource Media in partnership with the NWF Great Lakes Regional Center, several
condition are contributing to the spread of toxic algae and lake closures. They
include heavy rains increasing the volume of fertilizers and livestock manure
entering waterways, failing septic systems, and high summer temperatures.
Algae, such as cyanobacteria, can produce toxins that harm humans and pets and
can damage tourism tied to lakes and other waterways, the news release says.
report urges federal public officials to set limits on phosphorus entering
waterways, to maintain efforts to restore waterways, and to pass a strong Farm
Bill that pays farmers to take actions to protect soil and water quality, the
news release says.
the map at www.toxicalgaenews.com and the report at
collect data on ocean temperature and marine species
gliders have traveled between the East Coast of North America and the
Continental Shelf Break to collect oceanographic and animal-tracking data,
according to a Dalhousie University (Halifax, Nova Scotia) news release. The 14
autonomous gliders were equipped with sampling instruments to collect, store,
and transmit data on the shelf’s thermal structure for forecasting major storms
and informing migration patterns of various marine animals.
from U.S. and Canadian institutions teamed up to coordinate this large-scale
survey to monitor the oceanographic conditions that directly influence storms
and animal migration. Rutgers University (New Brunswick, N.J.) leads the
mission. Dalhousie-based Ocean Tracking Network (OTN) and the U.S. Integrated
Ocean Observing System also are participating.
contributed two Slocum gliders; these gliders move by altering their density to
ascend or descend in the water column. Wings on the gliders convert vertical
motion into forward motion.
of the gliders are equipped with Vemco (Bedford, Nova Scotia) mobile
transceivers to record the presence of acoustically tagged animals. Gliders
also will collect thermal data from the shelf because differences between air
and sea temperatures power hurricanes, the news release says.
data collected during the mission at http://gliders.oceantrack.org
greens remove heavy metals from water
and other similar leafy greens may offer more than just flavor for food. Ivy
Tec Community College (Carmel, Ind.) researchers working with Universidad
Politécnica de Francisco I (Hildago, Mexico) scientists found that these plants
show promise as biosorbents to remove lead and other potentially toxic heavy
metals from water, according to an American Chemical Society (ACS; Washington,
D.C.) news release.
research, presented at an ACS meeting, showed that the microscopic cells that
comprise the plant’s outer walls may be suited for sorption of heavy metals,
the news release says. Related plants, including parsley and cilantro, also
have similar features that could make them biosorbents, explained university
researcher Douglas Schauer at the meeting. Small-scale experiments showed that
cilantro may be more effective than activated carbon in removing heavy metals such
as lead, the news release says.
cilantro grows in abundance in developing countries that need an inexpensive
option to filter for heavy metals, use of the plant to filter water may provide
a lower-cost alternative to traditional treatment such as using activated
carbon or ion-exchange resins. Cilantro could be used in packets or reusable
water filter cartridges, the news release says.