PAPER making! FROM THE PUBLISHERS OF PAPER TECHNOLOGY INTERNATIONAL Volume 6, Number 1, 2020
WASTE TREATMENT Nanocellulose Ǧ Enabled Membranes for Water Purification: Perspectives, Priyanka R. Sharma et al, Advanced Sustainable Systems (2020), online . Membrane technology remains the most energy Ǧ efficient process for removing contaminants (micrometer Ǧ size particles to angstrom Ǧ size hydrated ions) from water. However, the current membrane technology, involving relatively expensive synthetic materials, is often nonsustainable for the poorest communities in the society. In this article, perspectives are provided on the emerging nanocellulose Ǧ enabled membrane technology based on nanoscale cellulose fibers that can be extracted from almost any biomass. It is conceivable that nanocellulose membranes developed from inexpensive, abundant, and sustainable resources (such as agriculture residues and underutilized biomass waste) can lower the cost of membrane separation, as these membranes offer the ability to remove a range of pollutants in one step, via size exclusion and/or adsorption. The nanocellulose Ǧ enabled membrane technology not only may be suitable for tackling global drinking water challenges, but it can also provide a new low Ǧ cost platform for various pressure Ǧ driven filtration techniques, such as microfiltration, ultrafiltration, nanofiltration, and reverse osmosis. Some relevant parameters that can control the filtration performance of nanocellulose Ǧ enabled membranes are comprehensively discussed. A short review of the current state of development for nanocellulose membranes is also provided. Pulp and Paper Mill Wastewater: Ecotoxicological Effects and Bioremediation Approaches for Environmental Safety, Izharul Haq & Abhay Raj, Bioremediation of Industrial Waste for Environmental Safety, pp.333-356 (Springer) . Pulp and paper industry is one of the important industrial sectors in India, which consume huge amount of water in the papermaking process. The final wastewater is often characterized by high color, BOD (biochemical oxygen demand), COD (chemical oxygen demand), AOX (adsorbable organic halides), SS (suspended solids), TDS (total dissolved solids), phenolics, heavy metals, and plant components like lignin, tannin, resin acids, and extractives. Finally, these compounds are reached to aquatic and terrestrial ecosystem and causing serious environmental pollution. The generated wastewaters are treated by conventional biological treatment like activated sludge process (ASP) after primary treatment. Biological treatment of paper mill effluent significantly removes BOD, COD, SS, and also COD, but it is insufficient in removal of lignin and chlorophenols due to its low biodegradability and toxicity. During last few decades, several physical and chemical methods have been developed with the aim to use as pre- and posttreatment method. However, application of this technology at large scale is costly. Therefore, bioremediation which involve the use of pollutant-specific microorganism for wastewater treatment has been considered as cost-effective and eco-friendly treatment method. Thus, this chapter provides the updated information on paper processing and wastewater generation and their characteristics and toxicity. Processes based on physicochemical and biological methods for the treatment of pulp and paper mill wastewater have been also discussed. Cationic Polyacrylamide Emulsion with Ultra-high Concentration as a Flocculant for Paper Mill Wastewater Treatment, Kaiji Yang et al, BioResources, Vol.15(2) . Cationic polyacrylamide emulsions prepared with ultra-high concentration (CPAME-uhc) have the advantages of fast dissolution, convenient operation, and low transportation cost. In order to further improve the molecular weight, solubility, and temperature/salt resistance of CPAME-uhc, in this study the preparation process of CPAME-uhc was optimized, and the effects of solubilizing agents and functional monomers on solubility and temperature/ salt resistance of CPAME-uhc were evaluated. Finally, the flocculation performance of CPAME-uhc on papermaking wastewater was examined. The results showed that the
Technical Abstracts
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