Water is one of the most important natural resources on Earth. It is not only fundamental to life but also essential to the wealth of countries contributing to all aspects of personal welfare and economic life.
However, global drivers such as climate change, population growth and improving living standards increase pressure on water resources. This is particularly the case in developing and fast-growing countries where rapid industrialisation increases demand water with clear effects on the supply of safe drinking water and access to adequate sanitation services for the population. Consequently, there is an emerging gap between safe freshwater availability and water demand. To ensure the sustainability of water resources, major efforts must be made by governments and industries. Implementation of government policies must be undertaken. Various water initiatives are actually considered by governments, including water footprinting, business risk assessment frameworks, reporting and disclosure protocols, as well as standards and certification frameworks. From the industry side, such policies will force them to review their actual management practices and develop new approaches and strategies.
The pulp and paper industry is a major user of water. It ranks third in the world, after the metals and the chemical industries in terms of freshwater consumption. Economic issues combined with strict environmental regulations are the driving forces for water reduction use at paper mills. Although they have for a long time now implemented measures to reuse process waters, there is still room to improve water and energy savings through further reduction of freshwater consumption. However, advanced wastewater treatment methodologies will be mandatory.
We are actually conducting studies to develop a multifunctional adsorbent filter media using electrospun nanofibers for the removal of contaminants from aqueous solutions. The main features of the device is that it is a non-woven three-dimensional porous mat made of randomly laid nanofibers in the size range of 3 nm to 5 μm produced by electrospinning which provide a physical, sized-based separation mechanism for the filtration of contaminants. Polymeric nanofibers with very small diameter have unique properties, such as high specific surface area and surface functionalities. It is possible to make nanofibrous media with low basis weight, high permeability and small pore size that should overcome common technical problems encountered with most usual processes used for water treatment, namely packed bed adsorption column and membrane filtration. Such a device should be able to generate low-pressure drop, high adsorption capacity and low fouling behaviour. Actually, we are investigating Chitosan for nanofibre production. Chitosan is attractive since it has a strong chelation potential for heavy metals due to the presence of amine and hydroxyl groups on the surface that is involved in the adsorption process. Chitosan is a biodegradable, natural, and non-toxic polymer derived from chitin which is readily available at a very cheap cost since it is essentially a waste product from the fishing and marine industries. The device will also be used to test wastewaters from the mining industry and municipal wastewaters targeting emerging contaminants released by chemical and pharmaceutical industries.
Dr. Bruno Chabot
Université du Québec à Trois-Rivières
Chemical Engineering Department,
Tel: (819) 376 5011 ext. 4510