Treatment of landfill leachate using sawdust, rice husk, activated charcoal, and caustic soda

Abstract

Landfill leachate has organic and inorganic contaminants that produce
offensive odour and can migrate to pollute surface and underground
water. This paper therefore seeks to utilise sawdust, rice husk, chemical
activated charcoal, sand and caustic soda and physicochemical
processes to remove contaminants from the leachate to make the water
safe to be discharged to the environment. The leachate obtained from
Kpone Engineered Landfill was passed through absorbent columns
designed from the following: charcoal, sawdust, sand and rice husk. The
concentrations of copper, iron, lead, cadmium, manganese, chromium,
and zinc were assessed. The pH, total dissolved solids, true colour,
apparent colour, turbidity and electrical conductivity were determined.
The stratified bed with rice husk at the top followed by sawdust and sand
bed showed highest removal efficiency of 89.6 %. The effluent obtained
from the multistage adsorption was subjected to chemical precipitation of
which 100% of the parameters met WHO Drinking Water Standard.