Plumbing: US groups join in water efficiency research

The US Environmental Protection Agency (EPA) hosted a January 6, 2009, memorandum of understanding (MOU) signing ceremony for five national organizations that have joined forces to do further research into water efficiency in plumbing, according to the Web site of the Chicago-based Alliance for Water Efficiency, the organization leading the partnership, that further consisted of:

• International Code Council
• International Association of Plumbing and Mechanical Officials (IAPMO)
• Plumbing, Heating, and Cooling Contractors Association
• Plumbing Manufacturers Institute.

The organizations pledged to develop research programs to assist in the development and use of water-efficient plumbing. The research will cover efficient and sustainable products, systems and practices, including:

• high-efficiency toilet drainage
• water reuse systems
• non-water consuming urinals, and 
• sizing of water-efficient plumbing systems

Source: Water Technology Online, 06 Jan 2009

Poop-Powered Hydrogen Cars Show Promise

New research from Kajima, a Japanese company, and Tokyo University, suggests that microbes from human waste could be a good source for hydrogen fuel cell cars. According to a report yesterday on Japan’s Nikkei, the company has produced a fuel cell that has generated 130W from each cubic meter of waste. Kajima believes it will take another decade to commercialize the product.

Researchers from the University of California, and administrators at California’s Orange County Sanitation District, appear to be further along. Last fall, they installed an $8 million fuel-cell device to convert human waste into hydrogen fuel. In an interview with the Orange County Register, Scott Samuelsen, director of UC Irvine’s National Fuel Cell Research Center who helped develop the device, said, “The waste stream from society is being turned around, and providing energy and transportation fuel for the society. “

Read More: HybridCars.com, 05 Jan 2088

Arsenic mitigation: Bangladesh and Vietnam – different groundwater compositions require different approaches

Hug, S.J., Leupin, O.X. and Berg, M. (2008). Bangladesh and Vietnam : different groundwater compositions require different approaches to arsenic mitigation. Environmental science and technology ; vol. 42, no. 17 ; p. 6318-6323. DOI: 10.1021/es7028284

To be successful, the mitigation strategy must take into account the geological differences in groundwater, the economic resources of the population, and the availability of infrastructure for water treatment.

Conclusions:

Vietnam and Bangladesh are both confronted with high arsenic concentrations, but distinct water compositions require different solutions. Arsenic mitigation depends for the most part on natural factors, such as the availability of alternative water sources and the feasibility of water treatment.  If several options are available, socioeconomic factors determine which mitigation option is implemented most successfully.

The socially accepted and already widespread sand filters in the Red River delta have advantages for their simplicity and low cost of operation. The removal of iron from the pumped water is immediately apparent even to people who are not aware of the arsenic problem. Thus, sand filters are a good option in Vietnam and in other affected regions with high concentrations of dissolved iron.

Arsenic removal in the worst-affected districts of Bangladesh is considerably more difficult. Since there are currently no selective sorbents, both arsenic and phosphate have to be removed and fixed-bed columns will require frequent regeneration or replacement. Activated alumina columns that can be regenerated have shown very good results. Filter columns with zerovalent iron are very promising, as metallic iron is inexpensive, widely available, and capable of forming precipitates with very high sorption site densities. An
improved understanding of the reactions over long periods of operation can lead to further optimization and wider applicability. An issue that is often discussed is the sludge produced in water treatment units. Sludge with elevated arsenic concentrations needs to be collected and handled properly. Containment under oxic conditions or in closed disposal sites are good solutions. However, the quantities of arsenic in water used for drinking are small compared to the amounts of arsenic pumped into rice fields by irrigation and probably partly remobilized during monsoon flooding. In the long term, controlled transport and release of treatment
sludge into large rivers during high water levels, ensuring rapid dilution and transport into the ocean, could be studied as an alternative to containment. Several mitigation options are now available and should be implemented to avoid further exposure to arsenic-tainted drinking water.

IX Latin-American Workshop and Symposium on Anaerobic Digestion, 18-19 Oct 2008, Easter Island, Chile

Anaerobic digestion represents nowadays one of the most cost-effective alternatives for waste (water) treatment, which has experienced a fast development during the last three decades. This Latin-American Workshop and Symposium will offer a selected program including the latest research findings and technological applications on anaerobic wastewater treatment, solids stabilization and biogas production as a renewal energy source.

This event is addressed to researchers, waste managers, consultants, representatives of both public and private sectors, environmental engineers and other related professionals.

Organised by the International Water Association (IWA).

For more information go to the conference web site

Beetle-Based Water Harvesting

A pioneering water harvesting system inspired by the Namib Desert Beetle is one the biomimicry innovations that will feature in the first annual edition of Nature’s 100 Best© book. The book is an initiative of ZERI, Biomimicry Guild and the Biomimmicry Institute, in cooperation with IUCN, and UNEP.

The Namib Desert beetle lives in a location that receives a mere half an inch of rain a year yet can harvest water from fogs that blow in gales across the land several mornings each month. A team from the University of Oxford and the UK defense research firm QinetiQ, have designed a surface that mimics the water-attracting bumps and water-shedding valleys on the beetle’s wing scales that allows the insect to collect and funnel droplets thinner than a human hair.

The patchwork surface hinges on small, poppy-seed sized glass spheres in a layer of warm wax that tests show work like the beetle’s wing scales.

Trials have now been carried out to use the beetle film to capture water vapour from cooling towers. Initial tests have shown that the invention can return 10 per cent of lost water and lead to cuts in energy bills for nearby buildings by reducing a city’s heat sink effect.

An estimated 50,000 new water-cooling towers are erected annually and each large system evaporates and loses over 500 million litres.

Other researchers, some with funding from the US Defense Advanced Research Agency, are mimicking the beetle water collection system to develop tents that collect their own water up to surfaces that will ‘mix’ reagents for ‘lab-on-a-chip’ applications.

Source: UNEP, 28 May 2008