TY - JOUR
T1 - Start-up of UASB reactors treating municipal wastewater and effect of temperature/sludge age and hydraulic retention time (HRT) on its performance
AU - Rizvi, Hina
AU - Ahmad, Nasir
AU - Abbas, Farhat
AU - Bukhari, Iftikhar Hussain
AU - Yasar, Abdullah
AU - Ali, Shafaqat
AU - Yasmeen, Tahira
AU - Riaz, Muhammad
N1 - Publisher Copyright:
© 2014.
PY - 2015
Y1 - 2015
N2 - The upflow anaerobic sludge blanket reactors seeded with cow dung manure (UASBCD) and activated sludge of a dairy wastewater treatment plant (UASBASDIT) were used to treat raw domestic wastewater of medium strength. The UASBCD reactor required a period of 120days to start up. In case of UASBASDIT reactor, sludge bed was stabilized in a period of 80days. The performance of both reactors to treat wastewater was enhanced with an increase in the sludge age and temperature. Under psychrophilic temperature (17°C) and at early sludge age (60days), chemical oxygen demand (COD) and biochemical oxygen demand (BOD) removal by the reactors were in the range of 57-62% and 61-66%, respectively. However, chemical oxygen demand (COD) and biochemical oxygen demand (BOD) removal efficiency of the reactors elevated to the range of 79-81% and 77-83%, respectively at sludge age of 150days and temperature of 30°C. In short, overall performance of both reactors was optimum at sludge age ranging from 120 to 150days and temperature varying between 25 and 30°C. At hydraulic retention time (HRT) of 9h the chemical oxygen demand (COD), total suspended solids (TSS) and sulfate removal efficiency of UASBCD reactor reached 81%, 75% and 76%, respectively and 77%, 74% and 69%, respectively for UASBASDIT. The rate of removal of these parameters however, gradually declined with increasing hydraulic retention time. The UASB technology provides a low-cost system for the direct treatment of municipal wastewater and can be applied in small communities.
AB - The upflow anaerobic sludge blanket reactors seeded with cow dung manure (UASBCD) and activated sludge of a dairy wastewater treatment plant (UASBASDIT) were used to treat raw domestic wastewater of medium strength. The UASBCD reactor required a period of 120days to start up. In case of UASBASDIT reactor, sludge bed was stabilized in a period of 80days. The performance of both reactors to treat wastewater was enhanced with an increase in the sludge age and temperature. Under psychrophilic temperature (17°C) and at early sludge age (60days), chemical oxygen demand (COD) and biochemical oxygen demand (BOD) removal by the reactors were in the range of 57-62% and 61-66%, respectively. However, chemical oxygen demand (COD) and biochemical oxygen demand (BOD) removal efficiency of the reactors elevated to the range of 79-81% and 77-83%, respectively at sludge age of 150days and temperature of 30°C. In short, overall performance of both reactors was optimum at sludge age ranging from 120 to 150days and temperature varying between 25 and 30°C. At hydraulic retention time (HRT) of 9h the chemical oxygen demand (COD), total suspended solids (TSS) and sulfate removal efficiency of UASBCD reactor reached 81%, 75% and 76%, respectively and 77%, 74% and 69%, respectively for UASBASDIT. The rate of removal of these parameters however, gradually declined with increasing hydraulic retention time. The UASB technology provides a low-cost system for the direct treatment of municipal wastewater and can be applied in small communities.
KW - Chemical oxygen demand (COD) and biochemical oxygen demand (BOD)
KW - Hydraulic retention time (HRT)
KW - Municipal wastewater
KW - Sludge
KW - UASB reactors
UR - http://www.scopus.com/inward/record.url?scp=85028221877&partnerID=8YFLogxK
U2 - 10.1016/j.arabjc.2013.12.016
DO - 10.1016/j.arabjc.2013.12.016
M3 - Article
AN - SCOPUS:85028221877
SN - 1878-5352
VL - 8
SP - 780
EP - 786
JO - Arabian Journal of Chemistry
JF - Arabian Journal of Chemistry
IS - 6
ER -