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k <br /> filter and ultimate effluent quality. In Figure 3, complex fiber structure and void space of textile <br /> fibers is compared to that of typical 0.30-mm and 1.5-mm sand particles. <br /> I <br /> Figure 3:Textile liber porous structure, <br /> relative to sand and gravel particles <br /> 1 ra <br /> F <br /> Performance of Textile-Based Packed Bed Filters <br /> f In the past three years,performance evaluations have been conducted and reported on by facilities such <br /> as the University of California, Davis Campus;NSF International; and NovaTec Consultants, Inc. of <br /> Vancouver, British Columbia. The University of California Davis study(Leverenz, et al., 2000)was <br /> conducted following standard method composite sampling and testing procedures. The evaluations <br /> performed by NSF International and NovaTec Consultants (Vassos and Turk, 2002)were conducted per <br /> ANSI/NSF Standard 40 protocol. The ANSI/NSF Standard 40 evaluation resulted in the first ever <br /> certification of a packed-bed textile filter under ANSI/NSF Standard 40 for Residential Wastewater <br /> j Treatment Systems. Over the course of the NSF40 evaluation, the average effluent cBOD5 was 5 mglL <br /> and the average effluent TSS was 4 mg/L at a hydraulic loading rate of 29.1 gpd/fe. The units evaluated <br /> contained vertically aligned textile sheets (AX) as shown in Figure 4. The evaluations successfully <br /> established the ability of this configuration to meet advanced wastewater treatment levels and surpassed, <br /> by a considerable margin, the effluent quality performance requirements established by ANSI/NSF <br /> Standard 40 for Class I effluent. <br /> Figure 4: AX20 AdvanTexo filter with <br /> aligned textile sheets <br /> ��• 3 S:vl"J 3 J (o� <br /> P , <br /> t <br /> Additional performance evaluation demonstrated the ability of the unit to function under peak design <br /> hydraulic and solids-loading conditions for extended periods of time,without service. Over a span of <br /> nearly 14 months,NovaTec Consultants (Vassos and Turk, 2002) continuously evaluated performance <br /> under peak hydraulic loading conditions (HLR). For 10 of those months, the HLR exceeded 60 gpd/ft2, <br /> and for a period of about 3.5 months the loading rate was 48.3 gpd/ft2. <br /> NTP-FLT-TRB-1 <br /> Rev.1.1,11102 <br /> Page 5 of 12 <br />