Journal of Applied Sciences1812-56541812-5662Asian Network for Scientific Information10.3923/jas.2004.493.497AdewumiI. OjoO.E. AribisalaO. 3200443Most Waterworks in Nigeria and other African developing countries still import
filter sand from developed countries for the operation of rapid filter beds
in water treatment facilities. The variation of the physical characteristics
such as permeability (k), equivalent diameter (deq) and sphericity
(ψ) of three types of filter sand (FS) grains were studied as they were degraded
by simulated abrasion. The flow rate and permeability coefficient of raw imported
FS at Ado-Ekiti waterworks and a locally-sourced FS at OAU waterworks were the
same at 1.5 cm3 s1 and 2.79x103 cm s1,
respectively compared with erosion sand?s values of 1.77 cm3 s1
and 3.3x103 cm s1 for the parameters. At the end of
more than 12% degradation, the flow rates for the imported, locally-sourced
and erosion sands reduced to 0.45, 0.35 and 0.23 cm3 s1,
respectively. The coefficient of permeability of the imported, local and erosion
FS also reduced to 8.38x104, 6.52x104 and 4.28x104cm s1, respectively. The work established that deq
might be used to predict when the filter media are due for replacement. The
method may be useful to engineers for FS material selection and projecting what
quantity may be required for stocking a water treatment plant.]]>Craig, K.,1986123647Bratby, J.R.,19887106121Ogedengbe, M.O.,198292023Tebbutt, T.H.Y. and R.C. Shakleton,198412174178Cleasby, J.L. and K. Fan,1981107445471Tebbutt, T.H.Y.,1977Hammer, M.J. and M.J. Jr. Hammer,19962nd Edn.,Fair, G.M., J.C. Geyer and D.A. Okun,1975McGhee, T.J.,19916th Edn.,Pages: 602Pages: 602Baver, L.D., W.H. Gardner and W.R. Gardner,1972Amirtharajah, A.,19701970Huisman, L. and W.E. Wood,1974Sheffler, G.H.,19691969pp: 139-161pp: 139-161Coker, O.,20032003pp: 9497Bagade, S.P.,20032003pp: 6366Baumann, E.R.,19781978Salvato, J.A.,1992pp: 214-472pp: 214-472