| Author | Youn, Jong-ho |
| Call Number | AIT Thesis no. EV-90-27 |
| Subject(s) | Hazardous wastes
|
| Note | A thesis submitted in partial fulfilment of the requirements for the degree of Master of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ;no. EV-90-27 |
| Abstract | A laboratory study was conducted to investigate the
immobilization of the laboratory waste s ludge, mainly from
chemical oxygen demand {COD) waste , using cementitious binders.
The binders were Ordinary Portland Cement {OPC), and lime -
Rice Husk Ash (RHA) cement. The sludges were mixed with cement -
sand mortar having a cement to sand ratio of 0.5, and water to
cemen t ratio of 0.5 for OPC mortar and 0.9 for lime - RHA ceme nt
mortar, respectively.
Physical properties lik e compressive strength and
leachability were studied to assess the effectiveness of the
binders in containing the waste sl udg es within their matrix .
Leachability was determined by the US EPA Extraction Procedure.
The leachability was found to be proportional to the
sludge/ cement ratios and inversely proportional to the curing
time. The compressive strength of OPC mortar was found to be
proportional to the curing time and inversely proportional to the
sludge/ cement ratios. On the contrary , the compressive strength
of lime - RHA cement mortar was found to be proportional to the
sludge/ cement ratios and a pyramidal trend was observed to curing
time.
The compressive strength of OPC mortar was found to be
greater than that of lime - RHA cement mortar. On the other
hand , leachabili ty of lime - RHA cement mortar was invariably
much less than that of OPC mort ar in all the tests. In this way ,
lime - RHA cement was found to be a better immobilizer than OPC.
Economic evaluation was done for three different kinds of
cementitious binders, namely, OPC, Portland Rice Husk Ash Cement
{PRHAC ) which contain ed rice hu sk ash 50 percent by dry weight,
and lime - RHA cement. The result showed that lime - RHA cement
was cheapest.
The applicability of Freundlich' s desorption isotherm was
studi ed to assess the l eachability of sludges. The leachability
of both cement mortars were found to follow the desorption
isotherms.
From this study , it is concluded that lime - RHA cement ,
which is cheaper than OPC, can be used as a cementitious binder
to solidify heavy metal sludge with much less leachability than
that of OPC, and its compressive strength s are high enough for
landfill disposal. Moreover , it is expected that lime - RHA
cement can be a solution to rice husk disposal problem . |
| Year | 1990 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. EV-90-27 |
| Type | Thesis |
| School | School of Environment, Resources, and Development |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Environmental Engineering (EV) |
| Chairperson(s) | Chongrak Polprasert; |
| Examination Committee(s) | Vigneswaran, Saravanamuthu ;Kim, Sun Il ; |
| Scholarship Donor(s) | Royal Thai Government ; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1990 |