کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
18560 42726 2006 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effect of sludge age on performance of an activated sludge unit treating 2,4 dichlorophenol-containing synthetic wastewater
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی بیو مهندسی (مهندسی زیستی)
پیش نمایش صفحه اول مقاله
Effect of sludge age on performance of an activated sludge unit treating 2,4 dichlorophenol-containing synthetic wastewater
چکیده انگلیسی

Wastewaters containing chlorophenol compounds are difficult to treat by biological means because of toxic effects of chlorophenols on microorganisms. Synthetic wastewater containing 2,4 dichlorophenol (DCP) was biologically treated in an activated sludge unit at different sludge ages varying between 5 and 30 days while the feed COD, DCP contents and hydraulic residence time (HRT) were constant. Effects of sludge age on COD, DCP and toxicity removals were investigated. Increases in sludge age caused significant increases in biomass concentration in the aeration tank, which resulted in increases in percent COD, DCP and toxicity removals. COD removal increased from 58 to 90%, while DCP and toxicity removals increased from 15 to 100% and from 38 to 100%, respectively, when the sludge age was raised from 5 to 30 days. Resazurin method based on dehydrogenase activity was used for assessment of the feed and effluent wastewater toxicity. Sludge volume index (SVI) decreased with increasing sludge age indicating improved settling characteristics of the sludge at high sludge ages. Operation at a sludge age of 25 days resulted in more than 90% COD and nearly 100% DCP and toxicity removal with an SVI value of 108 ml g−1 under the experimental conditions tested.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Enzyme and Microbial Technology - Volume 38, Issues 1–2, 3 January 2006, Pages 60–64
نویسندگان
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