CFD Based Parametric Analysis of Gas Flow in A Counter-Flow Wet Scrubber System
Bashir Ahmed Danzomo,
Momoh-Jimoh Enyiomika Salami,
Raisuddin Mohd Khan,
Mohd Iskhandar Bin Mohd Nor
Issue:
Volume 1, Issue 2, July 2013
Pages:
16-23
Received:
17 June 2013
Published:
10 July 2013
Abstract: Environmental protection measures regarding industrial emissions and tightened regulations for air pollution led to the selection of a counter-flow wet scrubber system based on applicability and economic considerations. The flow dynamics of gas transporting particulate matter and gaseous contaminants is a key factor which should be considered in the scrubber design. In this study, gas flow field were simulated using ANSYS Fluent computational fluids dynamic (CFD) software based on the continuity, momentum and k-ε turbulence model so as to obtain optimum design of the system, improve efficiency, shorten experimental, period and avoid dead zone. The result shows that the residuals have done a very good job of converging at minimum number of iterations and error of 1E-6. The velocity flow contours and vectors at the inlet, across the scrubbing chamber and the outlet shows a distributed flow and the velocity profiles have fully conformed to the recommended profile for turbulent flows in pipes. The total pressure within the scrubber cross-section is constant while the minimum and maximum pressure drops was obtained to be 0.30pa and 3.03pa which has conformed to the recommended pressure drop for wet scrubbers. From the results obtained, it can be deduced that the numerical simulation using CFD is an effective method to study the flow characteristics of a counter-flow wet scrubber system.
Abstract: Environmental protection measures regarding industrial emissions and tightened regulations for air pollution led to the selection of a counter-flow wet scrubber system based on applicability and economic considerations. The flow dynamics of gas transporting particulate matter and gaseous contaminants is a key factor which should be considered in th...
Show More
Zero Tolerance: Evolving Wildlife Management in Kenya
Shadrack Mumo Ngene,
Andrew Skidmore,
Hein van Gils,
Francis Kamau Muthoni,
Wycliffe Mutero,
Patrick Omondi
Issue:
Volume 1, Issue 2, July 2013
Pages:
24-31
Received:
28 May 2013
Published:
20 July 2013
Abstract: This study investigates the impact of contrasting wildlife management regimes on the probability of elephant presence in the Tsavo ecosystem base on the New York “zero tolerance policing”. Point data for the location of elephant, elephant carcasses, cattle, buffalo, giraffe, occupied bomas, charcoal kilns, settlements and farms, and water points were collected through aerial survey from 7-12 February 2011. Secondary data layers included main rivers, 30m resolution digital elevation model, and moderate resolution imaging spectro-radiometer (MODIS) 250m spatial resolution normalized difference vegetation index (NDVI) data for January 2011. Information on the three management regimes (none, passive, and active) adopted by protected areas and ranches in Tsavo ecosystem was identified through interviews. The Maxent algorithm was used for modeling the probability of elephant presence in the ecosystem. Multicollinearity of the fourteen explanatory variables was tested using Eigen values and Condition Index (CI). We used Maxent with elephant location points as the presence only data and the twelve explanatory variables as environmental variables. Bootstrapping of ten replications was included in the model. The accuracy of the model was determined using the area under the curve (AUC) of the Receiver Operating Characteristic (ROC) function. The results indicated that elephants were significantly more likely to be found in the protected areas than the non-protected areas. The northern sector of Tsavo West and the Voi sector of Tsavo East were the most likely areas to record elephants. Sectors with protected areas and ranches that practiced active management were more likely to show elephant than those with passive or no management. The areas with high probability of elephant occurrence coincided with actual high elephant density. Elephant carcasses, buffalo, giraffe, and settlements were the main variables that predicted the probability of elephant presence. Elephants are more likely to be in protected areas and ranches that were managed actively than those passively or not managed. In order to capitalize on the notion of protection and active management, we propose a wildlife management model based on the New York ‘zero tolerance’ policing. Any misdemeanor is not tolerated, especially illegal charcoal burning and livestock grazing in the ranches.
Abstract: This study investigates the impact of contrasting wildlife management regimes on the probability of elephant presence in the Tsavo ecosystem base on the New York “zero tolerance policing”. Point data for the location of elephant, elephant carcasses, cattle, buffalo, giraffe, occupied bomas, charcoal kilns, settlements and farms, and water points we...
Show More
Ecological Evaluation of Landscape Using Feng-Shui Theory at Shandiz Urban Region, NE Iran
Mohammad Reza Mansouri Daneshvar,
Sarah Khosravi,
Somayeh Rezayi
Issue:
Volume 1, Issue 2, July 2013
Pages:
32-37
Received:
20 July 2013
Published:
20 August 2013
Abstract: Landscape evaluation has an important role in developing and maintaining sustainability on local, regional and global scales. For this purpose different mathematical, empirical and traditional approaches were applied including Feng-shui theory. The basis of this theory refers to the Chinese traditional knowledge, examination and evaluation of the intrinsic energies of people and places. At the present study the site analysis and the landscape evaluation with Feng-shui theory were applied using the shapes and imaginaries of the landforms in the Shandiz urban region, northeast of Iran. The unsustainable development plans along the land use changes in this region has resulted in land degradations and natural hazards. Therefore, it is necessary to explain the traditional or ecological landscape evaluation at the study area. Based on the Feng-shui method we investigated the assigning nine-lattice zones map of the study area to achieve the ecological landscape evaluation. We think this method is a useful fresh traditional method for application in Middle East area. Our results exhibited that the central cave spot and four directions at the study area had spatially adaptation on the Lo-shu tablet in the nine landscape zones. These zones revealed that the new optimal strategies based on Feng-shui variant characteristics which are the brief research outcomes of landscape evaluation.
Abstract: Landscape evaluation has an important role in developing and maintaining sustainability on local, regional and global scales. For this purpose different mathematical, empirical and traditional approaches were applied including Feng-shui theory. The basis of this theory refers to the Chinese traditional knowledge, examination and evaluation of the i...
Show More
