TITLE:
Influence of the Nature of the Incoming Sludge on the Performance of a Vertical Flow Reed Beds in Dakar-Senegal
AUTHORS:
Elhadji Mamadou Sonko, Diomaye Dieng, Maïmouna Lo, Cheikh Diop
KEYWORDS:
Biosolid Quality, Dewatering Performance, Planted Drying Beds, Purification Performance, Sludge Type
JOURNAL NAME:
Journal of Water Resource and Protection,
Vol.16 No.6,
June
14,
2024
ABSTRACT: This work investigates the influence of the type sludge on drainage, plant development, purification performances and biosolids quality. Drainage properties were measured through the frequency of clogging, the percentage of leachate recovered and the dryness of accumulated sludge. Plant development was measured through the density, the height and the stem diameter. Purification performance was evaluated from the reduction rate. Biosolids quality was measured after 3 months of maturation. The results show that the clogging frequencies were 9.5%; 0% and 3.7%; the volume of leachate recovered was 42.2%; 20.4% and 24.7% and, the dryness was 33.4%; 61.1% and 52.4% for FS-ST, FS-STT and SS respectively. Plants densities were about, with densities 197.1, 171.3 and 178.3 plants/m2 in beds fed respectively with FS-ST, FS-STT and SS. Despite the high removal rates, the concentrations of pollutants in the leachates are above the Senegalese standard NS 05-061 for discharge into the environment. The biosolids are all mature with C/N and
N
H
4
+
/
N
O
3
?
ratios lower than 12 and 1 respectively. The biosolids are also rich in organic and mineral elements. The concentrations of Ascaris eggs are higher than the WHO recommendations. These biosolids should be stored for additional time or composted.