Abstract:
Water hardness has been associated with various human health problems. In many developing
countries, groundwater is the main source of drinking water. Water hardness has a significant
impact on groundwater quality, especially in arid and semi-arid regions, leading to
wasted financial investments in borehole drilling and worsening community
accessibility to potable water.In this study, relatively cheap and readily available raw
materials were used to remove total hardness from groundwater in a laboratory scale column
setting. In thisstudy, design parameters for a filter to remove total hardness from
groundwater were investigated. The optimal design parameters for the packed column were
as follows: area (A) of 265.0 cm2
and diameter (d) of 18.4 cm, at a flowrate (Q) of 75.0 cm3
/min.
For the field hard water flowrate of 2.0 mL/min, the optimal empty bed contact time was 70.7
min whereas the breakthrough time was about 430 min. Also, for the field hard water, the results
showed that competing ions from other contaminants in groundwater lowered the materials
adsorption capacity. Results from this study indicated that Cashew-nut Shell Activated Carbon
may be used to adequately remove total hardness from groundwater.Using these results, a pilot
filter was designed. The designed water hardness filter may provide the much-needed solution to
many potable water problems facing communities in most developing countries.
Keywords:Activated carbon; Cashew-nut shells; Column design; Groundwater; Hardness
removal;Water filter
