tailieunhanh - Low strength effluent treatment with cyclic technologies in Vietnam

Wastewater with low pollution concentrations are common in cities of the developing countries also in Vietnam because sewer network for wastewater is not yet construction that rely on combined sewer network. The results of the decomposition of organic matter partly in combined sewer network significantly reduced levels of BOD, while reducing nitrogen only a small part. The imbalance of BOD, nitrogen ratio is a challenge for treatment of wastewater - especially to ensure the nitrogen meets requirements. | LOW STRENGTH EFFLUENT TREATMENT WITH CYCLIC TECHNOLOGIES IN VIETNAM Eng Nguyen Phuong Quy1 Le Thanh2 Vu Duc Toan3 Abstract Wastewater with low pollution concentrations are common in cities of the developing countries also in Vietnam because sewer network for wastewater is not yet construction that rely on combined sewer network. The results of the decomposition of organic matter partly in combined sewer network significantly reduced levels of BOD while reducing nitrogen only a small part. The imbalance of BOD nitrogen ratio is a challenge for treatment of wastewater - especially to ensure the nitrogen meets requirements. Results of the analysis of influent and effluent concentrations in Yen So Hanoi Vinh Nghe An wastewater treatment plants where applied cyclic activated sludge technologies base on sequencing batch reactors with good control of operation to show that the effluent quality is stability and meet Vietnamese standard. Keywords Nitrogen removal nitrification denitrification cyclic activated sludge technology modified SBR SBR. BACKGROUND In 1995 Vietnam had issued the Environmental Protection Law but until 2002 the criteria for municipal wastewater treatment TCVN 7222 2002 was issued with requirements for some parameters. The regulations for wastewater treatment plant that contained secondary treatment stage are BOD 30mg l TSS 30mg l Total N 30mg l Total P 12mg l. NH4-N had not been regulated. In 2008 Ministry of Natural Resources and Environment issued QCVN 14 2008 BTNMT 11 regulations for municipal wastewater which was applied in parallel with TCVN 7222 2002. QCVN 14 2008 BTNMT contains two limits-specified in column A in case the effluent discharge to the basin that used for domestic water supply and column B others as given in Table 1. Generally in Vietnam s the industrial factories often in the city but the industrial wastewater is 1 SFC Vietnam JV Investment Development for Environment Corp. Phu Dien bld. 2 Phu Dien Construction Investment and .