Chemical Engineering & Technology
Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Every month, the Editors select two papers referring to current discussions in the scientific, public and economic communities and in view of the potential for further developments. The papers are freely accessible for one month.
Membrane Bioreactor for Simultaneous Wastewater Treatment and Energy Production
December 03, 2013
In the past two decades, remarkable progress has been made in the application of membrane bioreactor (MBR) processes for wastewater treatment and reclamation. Additionally, microbial fuel cells (MFCs) have emerged as a promising technology for wastewater treatment and energy recovery. In a combined MBR-MFC system, MFC can generate power from wastewater to partially offset the energy requirements for aeration in MBR, and MBR may solve the drawbacks of MFC due to its high biomass concentration and high efficient pollutant degradation ability. Zhiwei Wang et al. developed a bioeletrochemically assisted MBR for efficient wastewater treatment and energy production by successfully incorporating MFC and MBR processes. The analysis of electrochemical activity confirmed that the stainless steel mesh with biofilm functioned well as biocathode in the system. Denitrification also occurred in the cathode chamber, indicating that nitrate can compete with oxygen to capture electrons transferred from the anode. A longer hydraulic retention time and a lower volumetric loading rate could facilitate the power production and a maximum power density of 8.62 Wm–3 was achieved.
Z. Wang*, J. Huang, C. Zhu, J. Ma, Z. Wu
A Bioelectrochemically Assisted Membrane Bioreactor for Simultaneous Wastewater Treatment and Energy Production
Chem. Eng. Technol. 2013, 36 (12), 2044–2050.
December 03, 2013
Biomass energy as a kind of clean energy has attracted great attention since it can be easily gasified to produce syngas or fuel gas. Additionally, it can be converted to fuel ethanol through hydrolysis and fermentation technologies or to bio-oil via pyrolysis technologies. The latter technologies include flash pyrolysis, microwave pyrolysis, vacuum pyrolysis, vortex pyrolysis, and rotating-cone pyrolysis. However, bio-oil, which contains a high content of oxygen, is of low calorific value and poor thermal stability. These disadvantages restrict its extensive application and replacement of fossil fuels and necessitate further research. Qingli Xu et al. developed a novel kind of bio-oil upgrading technique under CO atmosphere. The oxygen content decreased from an initial value of 40.34 % to 4.75 %, the water content from 17.8 % to 2.7 %, and the pH value of the upgraded bio-oil was higher than that of crude bio-oil. In conclusion, it can be stated that the upgraded bio-oil exhibits a higher stability than crude bio-oil.
Q. Xu*, Z. Zhang, Y. Yan
Effect of a Ni-Based Catalyst on Bio-Oil Upgrading under CO Atmosphere
Chem. Eng. Technol. 2013, 36 (12), 2163–2168.