TITLE:
Recycling of Alum from Water Treatment Residue and Reuse It as a Flocculating Agent for Raw Water Treatment
AUTHORS:
Pascaline Sanga, Yves Iradukunda, Jean Claude Munyemana
KEYWORDS:
Sludge, Alum, Flocculation, Turbidity, Kimisagara
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.6 No.12,
December
29,
2018
ABSTRACT: The chemical coagulation-flocculation technology is touted as one of the valuable
techniques and widely used for wastewater treatment because of its
simplicity and effectiveness. So far, a number of flocculants have been fabricated
to ameliorate the flocculation process in water treatment such as alum,
polyaluminium chloride. Despite its broad application in water treatment,
accumulation of alum in sludge has been reported as the main source of a
disposal problem. Furthermore, recent studies suggested that the presence of
alum in sludge may lead to human health problems. Here in, we have used
alkalization method to recover alum present in sludge collected from Kimisagara
water treatment plant located in Kigali capital city of Rwanda. The recovered
alum was used more than one time and showed excellent flocculation
efficiency. Some physical parameters such as pH, Total Suspended Solids
(TSS), Total Dissolved Solids (TDS), Conductivity and Turbidity were systematically
tested and compared with those of World Health Organization
(WHO) and Rwanda Standards Board (RSB) standards for drinking water.
The results showed that alum present in sludge can be recovered and reused
for multiple times.