Author: Prof. Hoi Yeung Mehrdad Silatani
Dept: Centre for Oil & Gas Engineering, School of Energy, Environment & Agrifood, Cranfield University
Report No: 15/HY/633
Date: September 2015
The aim of the project has been defined to evaluate and investigate the performance of
a new filter media known as OC-1 Media against conventional sand filters used in
Identical experimental rigs for sand and OC-1 Media filters were assembled for comparing the effectiveness and efficiency of the filters against one another.
OC-1 Media achieved the target NTU value by consuming considerably less energy while operating at lower pressure and constant flow-rate than sand filtration.
In conclusion, the OC-1 Media has been found to be as effective as sand filtration in
filtering swimming pool water whilst being more cost effective in terms of its power
consumption and more reliable in terms of its flow rate.
Photographs showing set-up layout
3D representation of the experimental setup
Piping layout and flow direction of each filtration system
Power Consumption monitoring devices
Two identical power consumption meters were plugged into the mains upstream of the
adjustable speed pumps for monitoring the pump’s power usage.
For monitoring pressure of the filtration system, a pressure gauge was installed on top of each filtration vessel. At the point of sampling water from each tank, pressure values of each tank were logged by using the installed pressure gauges.
In-line floating flow meters were installed on the downstream line of the filters, which carry filtered water back to the water tank. Similar to pressure readings, flow-rate values were logged every time a water sample was taken to measure NTU values.
Figures 10 and 11 represent the power consumption and system’s pressure respectively.
The increase in power consumption by sand filter can be attributed to the gradual increase in pump’s speed in order to maintain a constant flow-rate.
The main conclusions from conducted tests can be summarised as follows:
• OC-1 Media proved to be as effective as traditional sand in reaching a target NTU value of 0.5.
• OC-1 Media has shown far greater capacity for filtering debris compared to traditional sand. In scenarios that cause the sand filter to block in seconds due to the heavy debris load, OC-1 Media continues to filter without a noticeable change in the system’s pressure or flow-rate. This signifies an advantage of OC-1 Media over sand as it requires backwashing less frequently.
• In terms of power consumption, OC-1 Media consumes considerably less power for delivering the same filtration performance in comparison to traditional sand.
• The OC-1 Media exhibited constant pressure and flow-rate throughout the testing period whereas traditional sand did not.
To sum up, by using OC-1 Media, one can expect a significant reduction in the power consumption of the system as well as greater capacity in filtering, while operating at a steady pressure and flow-rate.
OCM Products Ltd.
Kellet Close, Wigan, Lancashire, WN5 0LP
Patent protected technology
Community Design Registration No. 002701607-0001
Australian Design Registration No. 366671
US Design Patent No. D785,132 S (29/545,535)
Chinese Design Patent No. 201530453088.8
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