Comparison of Wastewater Treatment Technologies in the ED-WAVE Tool to Technologies of Similar Cases in Malawi: Case of Blantyre and Soche WWTW

This paper compares the wastewater treatment technologies at Blantyre and Soche wastewater treatment works (WWTW) in Malawi with technologies of a similar case according to the ED-WAVE tool to determine if existing cases in the tool can be invoked and appropriately modified to arrive at a particular design alternative. The ED-WAVE tool is a shareware PC based package for imparting training on wastewater treatment technologies. The system consists of four modules viz. Reference Library, Process Builder, Case Study Manager, and Treatment Adviser. The paper also compares the reduction in the levels of BOD5, COD, and TSS at the three respective treatment works. The study established that there is a similarity in the sequencing of treatment units of Municipal Case 6 in the ED-WAVE tool and the sequencing of treatment units at Blantyre and Soche WWTW, respectively. All the three plants incorporate screening, grit removal, aerobic biological treatment, and sedimentation. Soche and Blantyre WWTW use hand-raked inclined bar screens and constant velocity grit channels, where longitudinal flow velocity is hydraulically controlled. Rotary mechanically-raked bar screens and mechanically stirred grit chambers are used in the ED-WAVE tool. In addition, Municipal Case 6 uses oxidation ditches for aerobic biological treatment while Blantyre and Soche WWTW use trickling filters. BOD5 removal efficiency at Soche WWTW at 95% and 96% for dry season and wet season, respectively, is comparable to the removal efficiency at Municipal Case 6 (95%). The dry season BOD5 removal efficiency at Blantyre WWTW at 87% is slightly lower than the removal efficiency at Municipal Case 6. TSS removal efficiency at Soche WWTW is at 80% in the wet season and 35% in the dry season. TSS removal efficiency at Blantyre WWTW is only 3% in the wet season, while there is an increase of 11% in the wet season. TSS removal efficiency at Municipal Case 6 is 96%. Inspite of the difference in the BOD5 and TSS removal efficiencies at Municipal Case 6 as compared to Blantyre and Soche WWTW, there is a close match in technologies at Blantyre and Soche WWTW, and Municipal Case 6 in Greece as invoked by the Case Study Manager in the ED- WAVE tool. What is evident from this study is the need to appropriately modify the case arrived at through the Case Study Manager in order to come up with a design appropriate to the local situation in terms of operation and maintenance.

Erratum

Regarding “Outcome of Abdominal Aortic Endografting in High-Risk Patients: A 4-Year Single-Center Study,” which appeared in the December issue (2002;9:736–742), Dr. Simona Zannetti is employed by Medtronic as a Clinical Study Manager for Medtronic Europe, Peripheral Vascular Division. This information did not appear with the original article.

An Analysis of the Competencies of Sports and Athletic Club Managers

The focus of this study was to identify the competencies needed to manage athletic clubs and to determine if differences exist in required competencies regarding organizational size. A random sample of 264 managers participated in the study; there were 83 in Group I, 95 in Group II, and 86 in Group III. A one-way analysis of variance was employed for hypothesis testing, Tukey’s ω method was utilized for comparing rejected hypotheses, and factor analysis was used for clustering competency areas. Based on the findings of this study, manager competencies have been identified and a difference does exist in managing varying sizes of athletic clubs.