Analysis of Heavy Metals in Sludge and Bottom Ash from a Pharmaceutical
Industry

Meraj Ahsan Qureshi [1], Sarah Shakeel[2]
Page No. 143-157

The present study was conducted to estimate the quantity of ETP sludge generated by the
pharmaceutical industry per week and per year and to analyze the ETP sludge of pharmaceutical
industry and bottom ash that comes after the incineration of that sludge. Secondary sludge samples
were collected from effluent treatment plant of the industry and bottom ash samples were collected
from industrial incinerator using composite sampling technique. The pH, electrical conductivity,
Cr, Cu, Ni, Zn, Fe, Mn of ETP sludge and incinerator’s bottom ash were determined. Results were
analyzed statistically for mean, standard deviation, correlation and t-test. Results of incinerator’s
bottom ash were compared with USEPA standards (1996) to evaluate its toxicity. In bottom ash Cd,
Cr, Cu, Ni, and Mn concentrations were above and Pb, Fe and Zn were found under the permissible
limits set by USEPA. Positive correlation existed between the pH, electrical conductivity and heavy
metals concentration in ETP sludge and incinerator’s bottom ash. Pharmaceutical industry is
producing hazardous sludge, due to the presence of heavy metals. Controlled burning of ETP
sludge under high pressure and temperature (incineration) reduced the metal content of the sludge
along with reduced cost of sludge handling and disposal.
Keywords: Bottom Ash, Effluent Treatment Plant, Heavy Metals, Incinerator, Pharmaceutical
Industry, Sludge Disposal.