Effective depth, initial head loss and backwashing criteria as the key factors of burned oil palm shell (BOPS) granular filtration

Abstract

ab s t r ac tThese studies are mainly focused on effective depth, initial head loss and backwashing criteria that have been identified as the key factors in relation to the fundamental parameters and also, indicated possible operation performance. Granular filter media used in this study are limited to burned oil palm shell (BOPS) and sand. The study on the bed depth in relation to effluent over influent turbidities ratio (C e /C o ) has been found to exhibit an exponential relation which showed a strong correlation coefficient (R 2 = 0.9) for different effective sizes of BOPS (ES, 1.0-2.5 mm) and sand (ES, 0.4-0.9 mm). By approximating relatively constant C e /C o for both BOPS and sand at different effective sizes, an exponential equation (R 2 = 0.98) is proposed to link all effective bed depths. This enabled a determination of the effective depth of BOPS and sand media which were not executed in the experiment. Initial head loss of single media of BOPS and sand which involved comparison of different models, such as Ergun and modified Kozeny-Carmen equations with experimental results, at different flow rates, showed a good agreement with modified Kozeny-Carmen equation for non-sphere. In backwashing criteria, studies that showed the relation between the difference in granular settlement velocity with backwashing water velocity, confirmed that the best combination of dual-media are sand of ES = 0.5 mm with UC of 1.5 and BOPS of ES = 1.0 mm with UC of 1.3.

Modeling of Head Loss through Deep Bed Sand Filters. (Dept. C ( Public Works ) )

“…His results about the initial head loss (BOPS) media showed a good agreement with modified Kozeny-Carmen equation (Ergun equation). In this research the initial head loss for (BOPS) media was low compared to sand media with the same depth and velocity [10].…”

“…The above equations as stated in references [9], [10], [11] are used to determine the initial head loss where the filter media is clean. There is another equation that used to predict head loss as a function of time.…”

“…Head loss in clean filter Several empirical equations have been developed, which are used to predict clean filter head loss. Some of the more commonly used equations are provided as the following: [9], [10], [11] Carmen-Kozeny…”

Effect of Operational Conditions on Performance of Deep Sand Filter in Turbidity Removal

“…Through deep bed filters, not all used media depth is effective in turbidity removal but there is an effective depth which give the required or permissible limit. The effective depth for media from burned oil palm shell granular has been obtained [26]. Moreover, knowing the effective depth of turbidity removal will assist in identifying depth of the sand during filter design.…”

Burnt oil palm shell filter media for bacterial removing by single- and dual-media filtration

“…Therefore, the use of oil palm shell as in filter media production is highly essential and beneficial 978-1-4673-5968-9/13/$31.00 ©2013 IEEE 2013 IEEE Business Engineering and Industrial Applications Colloquium (BEIAC) since it will help to reduce the cost of treatment and could reduce dependency on other raw materials [10]. The burnt oil palm shells (BOPS) are prepared from solid waste of oil palm fruit shells which are the by-product from oil palm factories and are abundantly available in Malaysia [11]. In determining the performance of the filter media, water quality of the effluent was used as the main parameter for the indicator of filter performance.…”