PhD ThesisLandfill leachate with its variable and complex characteristics poses
a well established threat to the environment. Enhancement of the
environmental quality through the minimization of the leachate problem
should therefore be the major objective of good landfill management. The
need to control and manage landfill leachate has resulted in various
treatment alternatives which include both biological and physical-chemical
processes.
The research described in this thesis discusses the feasibility of
biological and physical-chemical treatment of leachate based on laboratoryscale
reactors. After a short introduction, a review of the relevant
literature on solid waste disposal including landfilling, leachate generation
and the treatment alternatives was presented. Comparative experimental
studies were then carried out using an aerobic rotating biological contactor
(RBC), an upflow anaerobic filter (UAF) and an activated carbon (AC)
adsorption column for treating landfill leachate. The effect of a range of
parameters on the performance and operation of the RBC, the UAF and the
AC column has been evaluated in the study
From the experimental results, an RBC was found to achieve a better
performance when treating a low strength (LS) leachate, whereas a high
strength (HS) leachate would be much better treated by a UAF. For the
LS leachate treatment, a COD removal of 80% at a loading rate of 6 kg
COD/m3.d was achieved by the RBC as compared to only 60% by the UAF.
Whereas for the HS leachate the RBC achieved a COD removal of only 50%
at the loading rate of 14 kg COD/m3.d as compared to 60% by the UAF. Direct physical-chemical treatment process in treating leachate using
an AC adsorption was also investigated. The results obtained showed that
the adsorption process was not capable of achieving the desired effluent
requirement, with 20% residual organic fractions still remaining in the
effluent. The need to remove this biodegradable organic matter by
biological processes was found to be necessary.
It is suggested that to achieve satisfactory treatment, anaerobic UAF
treatment of leachate followed by aerobic RBC and a final polishing with AC
column should be used.Universiti Teknologi, Malaysia