Filtration Term Paper Example | Topics and Well Written Essays - 4250 words

Filtration - Term Paper Example There are several methods through which the filtrate induced may flow through the filter medium. This may be by gravity (hydrostatic head), pressure being applied upstream of the filter medium, reduced pressure or vacuum being applied downstream the filter medium or through centrifugal sedimentation. (b) Filtration mechanism This may be through cake or clarifying filtration. Cake filtration is when the solid gets stopped at the surface of the filter medium where it piles upon one another to form a cake. Also known as depth or filter medium filtration, clarifying filtration is when the solids get trapped within the pores of the filter medium. (c) By objective The objective of the filtration process may be either dry solids or clarified liquid or both. The filtration process may be either intermittent or continuous. When classifying filters, they are first divided into either cake or clarifying filters. They are then classified depending on the driving force and then finally into eithe r batch or continuous classes. Continuous filtration testing and scale up In continuous filtration, it is first assumed that the resistance of both the filter cloth and the filter drainage is insignificant as compared to the resistance of the filter cake. It is also assumed that both specific cake resistance and pressure drop remain constant throughout the filtration process. ... Cake discharge A practical filter application is one which produces a cake that is thick enough to discharge. There are minimum acceptable cake thicknesses that are required for discharge for various types of filtration systems and discharge mechanisms. Therefore, when running small scale tests, the experimenter should decide early during the test program the applicable type of discharge then later tailor the data collected in a way that it will fit the physical requirements of that unit type. Feed slurry temperature An increase in the feed slurry temperature decreases the viscosity of the liquid phase. The overall result of this is an increase in the filtration rate and a decrease in the cake moisture content. Cake thickness control At times, the rate of cake formation with bottom feed type filters may be rapid enough in such a way that it creates a cake that is too thick for subsequent operations. The cake thickness can be adjusted by simply adjusting the bridge blocks found in the filter valve so as to decrease the effective submergence, through reduction of the slurry level in the vat, and also by reducing the vacuum level in the portion where the cake forms. Representative samples It is essential for the sample to be used as the representative of the slurry in full scale plants to be tested under the conditions prevailing in the process. If the slurry has a temperature that is different from the ambient temperature, subsequent heating or cooling may change the distribution of the particle size. The age of the sample may also influence the particle size significantly. If an effect is likely, the bench scale testing should be at the laboratory site or at the plant on

Effective Team and Performance Management Essay - 6

Effective Team and Performance Management - Essay Example The benchmark for turnaround times range between 12 p.m. and 2 p.m. The team leader ensured that each team member was equipped with bottled oxygen and steroids for emergency in case of serious exhaustion. Our team reached the Southeast Ridge Balcony approximately five and half hours after departure. This is one of the most difficult points to climb. Our team gradually ascended along the Balcony from around 8 a.m. to 10 a.m (Kayes, 2004). Did the team project work as expected or not expected? The team project did not work out as planned because not all members reached the summit. Most gave up ascending at Hillary Step due to wastage of time and snarl-ups. One of the expedition leaders breached the agreement regarding the order at which each team would begin for final summit. The team was not armed with radios for communication. One our team member was severely exhausted when we reached the Southeast Balcony. I together with another team pulled the climber with assisted with guide Sher pa. Moreover, our team was caught up in bottleneck. We could not proceed beyond that point because safety ropes had not been fixed. Our team together with other teams joined hands to secure the fixed safety ropes to secure our next mountain climbing session. This marked the onset of series of bottlenecks that were to occur in the course of our climbing. Our sojourn at Hillary Step took roughly an hour. Again, we were caught up in traffic snarl up, since long queue of climbers behind us was waiting for their turn to climb. Ropes had not been fixed as anticipated. We could not communicate to those below us, because we lacked radios. Unnecessary anxiety and confusion among climbers was looming. This point was approximately 28,800 feet beneath peak of Mount Everest. The previous climbers had not secured the ropes to facilitate ascent of those below at reasonable time (Kayes 2004). As a result, some team members arrived at the summit beyond the stipulated deadline at 2 p.m. The bottlenec ks had ripple effects, because it affected the whole operation. Things went astray between 4 p.m. to 5 p.m., because whiteout occurred, which grounded descent to near halt. The turnaround time was set at 12 hours after departure. The bottlenecks caused delays so that 6 hours past the deadline, snowstorm occurred and halted descent. Some team members ran out of oxygen supply. Fatigued ensued. Some team members were conspicuosly absent. The team members who abandoned the summit attempt at snarl up, and few climbers who successfully reached the summit, started arriving at Camp IV between 4.30 p.m. to 6 p.m. What factors contributed to your experience (e.g. personal, social) Mountain climbing at Mount Everest offered opportunity for unique research experience. Authorities restricted public investigations. As a result, empirical data regarding the Mount Everest Disaster of 1996 remains scanty. Also, the chronology of the tragedy was never archived. In order to create sense, the team crea ted chronology of possible events after painstaking review of observations by witnesses and survivors. A recent study (Kayes 2004) highlighted importance of integrated multiple analytic approach to tragedy sense-making. In order to ensure rational chronology of events, each team member conducted individual research, independence of chief investigations outlined in scholarly articles. The chronology was mounted on narratives, which contained