Khan, MA, Ngo, HH, Guo, W, Liu, Y, Nghiem, LD, Chang, SW, Nguyen, DD, Zhang, S, Luo, G & Jia, H 2019, 'Optimization of hydraulic retention time and organic loading rate for volatile fatty acid production from low strength wastewater in an anaerobic membrane bioreactor.', Bioresource technology, vol. 271, pp. 100-108.View/Download from: Publisher's site
This study aims to investigate the production of volatile fatty acids (VFAs) from low strength wastewater at various hydraulic retention time (HRT) and organic loading rate (OLR) in a continuous anaerobic membrane bioreactor (AnMBR) using glucose as carbon source. This experiment was performed without any selective inhibition of methanogens and the reactor pH was maintained at 7.0±0.1. 48, 24, 18, 12, 8 and 6h-HRTs were applied and the highest VFA concentration was recorded at 8h with an overall VFA yield of 48.20±1.21mg VFA/100mg CODfeed. Three different ORLs were applied (350, 550 and 715mg CODfeed) at the optimum 8h-HRT. The acetic and propanoic acid concentration maximums were (1.1845±0.0165 and 0.5160±0.0141mili-mole/l respectively) at 550mg CODfeed. The isobutyric acid concentration was highest (0.3580±0.0407mili-mole/l) at 715mg CODfeed indicating butyric-type fermentation at higher organic loading rate.
Khan, MA, Ngo, HH, Guo, W, Liu, Y, Zhang, X, Guo, J, Chang, SW, Nguyen, DD & Wang, J 2018, 'Biohydrogen production from anaerobic digestion and its potential as renewable energy', Renewable Energy, vol. 129, pp. 754-768.View/Download from: UTS OPUS or Publisher's site
© 2017. The current demand-supply scenario for fossil fuels requires an alternative energy source with cleaner combustion products whilst production of hydrogen from anaerobic digestion involves the utilization of waste materials and zero emission of greenhouse gasses. However, large scale industrial application has yet not been implemented due to numerous challenges in its production, storage, and transportation. This review study demonstrates that production of hydrogen from anaerobic digestion is potentially a worthy alternative regarding energy density, environmental impact, and cost. Moreover, dependence on fossil fuel systems in the future could be minimized when biohydrogen production is feasible from renewable energy sources.
Khan, MA, Ngo, HH, Guo, WS, Liu, YW, Zhou, JL, Zhang, J, Liang, S, Ni, BJ, Zhang, XB & Wang, J 2016, 'Comparing the value of bioproducts from different stages of anaerobic membrane bioreactors', Bioresource Technology, vol. 214, pp. 816-825.View/Download from: UTS OPUS or Publisher's site
Abstract The anaerobic digestion process in anaerobic membrane bioreactors is an effective way for waste management, energy sustainability and pollution control in the environment. This digestion process basically involves the production of volatile fatty acids and biohydrogen as intermediate products and methane as a final product. This paper compares the value of bioproducts from different stages of anaerobic membrane bioreactors through a thorough assessment. The value was assessed in terms of technical feasibility, economic assessment, environmental impact and impact on society. Even though the current research objective is more inclined to optimize the production of methane, the intermediate products could also be considered as economically attractive and environment friendly options. Hence, this is the first review study to correlate the idea into an anaerobic membrane bioreactor which is expected to guide future research pathways regarding anaerobic process and its bioproducts.
Khan, MA, Ngo, HH, Guo, WS, Liu, Y, Nghiem, LD, Hai, FI, Deng, LJ, Wang, J & Wu, Y 2016, 'Optimization of process parameters for production of volatile fatty acid, biohydrogen and methane from anaerobic digestion.', Bioresource technology, vol. 219, pp. 738-748.View/Download from: UTS OPUS or Publisher's site
The anaerobic digestion process has been primarily utilized for methane containing biogas production over the past few years. However, the digestion process could also be optimized for producing volatile fatty acids (VFAs) and biohydrogen. This is the first review article that combines the optimization approaches for all three possible products from the anaerobic digestion. In this review study, the types and configurations of the bioreactor are discussed for each type of product. This is followed by a review on optimization of common process parameters (e.g. temperature, pH, retention time and organic loading rate) separately for the production of VFA, biohydrogen and methane. This review also includes additional parameters, treatment methods or special additives that wield a significant and positive effect on production rate and these products' yield.
Atiqueuzzaman, KM, 'Optimizing Effective Absorption during Wet Natural Gas Dehydration by Tri Ethylene Glycol', IOSR Journal of Applied Chemistry, vol. 2, no. 2, pp. 01-06.View/Download from: Publisher's site