Abstract:
Water quality is a vital factor for the human health and well-being. Even though in most of the
areas in Sri Lanka have less impurity of water, people in dry zone are suffering from poor quality
of water mainly due to hardness. The objectives of the study were (a)to produce filter media
from natural materials such as moringa bark, rice husk, and natural sea sand, (b) to evaluate its
filter media properties, and (c) to evaluate them as a filter media for the removal of hardness
and turbidity in water. The filtration media were produced from natural sea sand (NSS),
carbonized moringa bark (CMB) and carbonized rice husk (CRH) and they were used for the
preparation of filter cartridges. Three replicates of filters were used to evaluate the filter
materials. Thirty liter of water was filtered through the filter as 2L batches. The drinking water
quality parameters; hardness, pH, Electrical Conductivity (EC) and turbidity were measured in
raw water and filtered water. Raw water hardness (270 mg/L), EC (1130 µs/cm), Turbidity
(12.0 NTU) and pH (6.2) of water were recorded and the same parameters of filtered water were
also measured during the filter evaluation process. Reasonable reduction of hardness was not
observed when these materials are used as filter media after converting into char. The changes
of hardness in three different filter media were significantly different. However, hardness
changes among moringa bark and rice husk were not significantly different. It was found that
reduction of hardness in natural soil was low compared with other filter materials. However, pH
and turbidity in filtered water were within the recommended limit of drinking water. Based on
the results of this study, the filter materials used to reduce hardness cannot be recommended
for the preparation of drinking water filter. However, further studies using the mixtures of these
materials in different ratios for the removal of hardness is suggested.
