PARENT SESSION
PT6 - Biomonitoring
Tuesday, 19 November 2002
8:00 AM to 6:30 PM
Exhibit Hall
(P646) Drainage and Spill Impacts over the Treatment System Microbiology and Quality of a Pulp Mill Effluent.
FURLEY, TATIANA*,1, CARVALHO OLIVEIRA, ALBERTO2, MONTENEGRO, EMILIO2, 1 APLYSIA ENVIRONMENTAL CONSULTING, VITORIA, ESP, SANTO, BRAZIL2 ARACRUZ CELULOSE S/A, ARACRUZ, ESP SANTO, BRAZIL
ABSTRACT- The Aracruz Celulose pulp mill secondary treatment system is composed of aerated lagoons. It is a biological process whose performance rate depends on microorganisms to biodegrade the contaminants. It is well established that the production of bleached kraft pulps yields a wide variety of compounds which appear in mill effluent and are toxic to organisms, mainly that compounds that come from drainages and spills. Changes in the composition of the waste effluent may cause significant reductions in the number of a particular bacterial population. As a result, the biodegradation of toxic substances and the efficiency of the biological process may be affected. The aim of this work is to evaluate the impacts of maintenance shutdown drainages, foul condenser overflow, black liquor spill and blackout drainage over the treatment system microbiology and quality of the treated effluent. The BOD, COD, color, AOX, pH and temperature values were determined weekly. The filamentous bacteria and protozoa microorganism examination and identification were also done using a Zeiss phase contrast microscope. The results showed that the impacts varied a lot depending on the drainage source and volume. The impacts can also be minimized depending on the drainage program management.
Key words: kraft pulp mill effluent, waste water treatment microbiology, drainage and spills impacts, filamentous bacteria