Adsorptive membrane treatment technologies may not have a low energy footprint

Adsorption is a low energy water and wastewater treatment technology. Thus, would the combination of adsorption and membrane treatment technologies lead to a low energy treatment system? The answer depends on the pore size of the membrane used in adsorptive membrane technologies, where the membrane surface serves as adsorbent for the sorption of heavy metals … More Adsorptive membrane treatment technologies may not have a low energy footprint

Energy requirement of forward osmosis membrane processes may not be lower than that of reverse osmosis

Forward osmosis is a relatively new membrane process for wastewater treatment. Specifically, it entails the addition of a volatile solute (such as ammonium carbonate) to the permeate side of the membrane for inducing the diffusion of water molecules across the membrane down a water concentration gradient. The volatile solute would be subsequently removed from the … More Energy requirement of forward osmosis membrane processes may not be lower than that of reverse osmosis

What is the value of an electric car to the environment at present: zero emissions or reduction in use of fossil energy?

Electric cars are often portrayed in the media as clean, zero emissions vehicles that tap on the latest innovations in renewable energy technologies. However, are they truly zero emissions vehicles and what is their most important contributions to environmental protection?   With an electric motor that runs on energy derived from the power grid, electric … More What is the value of an electric car to the environment at present: zero emissions or reduction in use of fossil energy?

Conventional drinking water treatment

All over the world, drinking water treatment comprises a specific set of steps designed to progressively remove various types of contaminants. Specifically, drinking water treatment comprises sedimentation, coagulation, filtration, sedimentation and disinfection.   When raw water first arrives at a drinking water treatment plant, it typically carries a heavy load of particles and is muddy … More Conventional drinking water treatment

Conventional drinking water treatment

All over the world, drinking water treatment comprises a specific set of steps designed to progressively remove various types of contaminants. Specifically, drinking water treatment comprises sedimentation, coagulation, filtration, sedimentation and disinfection. When raw water first arrives at a drinking water treatment plant, it typically carries a heavy load of particles and is muddy in … More Conventional drinking water treatment

Determining the effect of tropical cyclone on sediment transport by river

Article in Nature, Vol. 539, 10 November 2016, pp. 276, “Fluvial sediment supply to a mega-delta reduced by shifting tropical cyclone activity”   Summary of article: Effect of tropical cyclone on sediment transport along the Mekong river was estimated using a combination of hydrological models and sediment flow data. The authors may not be solving … More Determining the effect of tropical cyclone on sediment transport by river

Reverse osmosis is the only means for removing trace contaminants in water

Current drinking water treatment techniques, while effective, is increasingly unable to cope with the larger set of trace contaminants in treated water found to impact on human health. For example, in some areas of the world, treated water contains trace concentration of lead (~ 3 parts per billion, ppb level), arsenic (~ 2 ppb), boron, … More Reverse osmosis is the only means for removing trace contaminants in water

Taste of pure water produced through reverse osmosis

Reverse osmosis is increasingly used for desalination and purifying water unable to be treated by other means for removing trace contaminants known to impact on human health. However, what is the taste of pure water produced by reverse osmosis?   The answer is it is different from tap water. Specifically, Singapore uses reverse osmosis for … More Taste of pure water produced through reverse osmosis

Using microbes to convert coal to fuel gas

Perspective article in Science, Vol. 354, Issue. 6309, pp. 184, “A microbial route from coal to gas”   Summary of article: An interesting article outlining the conceptual basis of microbes mediated conversion of coal into methane, a fuel gas, which is an analog of the more commonly encountered process where microorganisms digest waste carbonaceous materials … More Using microbes to convert coal to fuel gas

Health concerns of using grey water to flush toilets

Water conservation is the main theme of discussion amongst future city planners and public utilities experts, and grey water is increasingly being put forward as a possible source of water for flushing toilets, as cities bid to reduce their overall water consumption. But, what is grey water and is it safe as a water source … More Health concerns of using grey water to flush toilets