TREATMENT OF COSMETIC WASTEWATER USING BIOLOGICAL TREATMENT TECHNOLOGY

Transcription

1 ABSTRACT B6-319 Ly Thuong Kiet, Ward 15, District11, HCMC TREATMENT OF COSMETIC WASTEWATER USING BIOLOGICAL TREATMENT TECHNOLOGY The wastewater treatment plant (WWTP) 15 m 3 /day capacity of Vinacosmo Company was investigated and built by a combination between the anaerobic and aerobic activated sludge treatment method. The analyzed wastewater results showed the effective performance in the COD, BOD and TSS removal. With > 96% removal efficiency for all factors, our chosen technology was proved as a right choice in cosmetic wastewater treatment. The effluent meets Vietnamese standard TCVN 5945:2005, B level. Keywords: Cosmetic wastewater, Aerotank, USAB 1. INTRODUCTION The cosmetic wastewater is mainly contaminated by chemicals, such as: surfactants, fatty acids, coconut oil, additives, oxidizers, mineral salts, suspended solids, The main cosmetic wastewater sources are coming from equipments and pipeline washing at the end of the working day or from the products changing. Therefore, the cosmetic wastewater varies on characteristics, components, capacity, and concentrations of pollutants, depending to the factory condition. The cosmetic wastewater from Vinacosmo company has two main characteristics are the capacity and COD changing. To ensure the treatment efficiency and economic performance, the biological method is usually used in reality. Because the high COD content, the cosmetic wastewater needs to treated anaerobic method before aerobic activated sludge treatment method. This is also the final technology which was utilized in the WWTP of Vinacosmo company. All steps of investigation and operation of the Vinacosmo WWTP will be described and summarized in this paper. 2. MATERIAL AND METHODS 2.1. Material Activated sludge used in textile WWTP was taken from stable aerotanks in other WWTPs which have the similar characteristics Methods Treatment technology Wastewater of Vinacosmo is collected in Pump sum, and then pumped to Equalization tank for stabilizing capacity and pollutant concentrations to ensure the treatment performance of biological tanks. The equalization tank is our solution for the characteristic changing of the Vinacosmo cosmetic wastewater. After going to the equalization tank, wastewater flows to UASB-Upflow anaerobic sludge blanket for organic components digestion in anaerobic environment. The next treatment step is Aerotank, which is used to decompose the BOD remaining in wastewater to simpler matters in aerobic condition. This condition is maintained by 1

2 air blower operation. The mixed liquor in the aerotank is pumped to Settling tank for sludge separation from this solution. The settled sludge at the bottom of this tank is returned to the aerotank to maintain the biological microorganism concentration (80 90%). The exceed sludge is pumped to Sludge drying bed to reduce the sludge moisture before going to landfill. The treated wastewater flows to Water tank and goes to the receiving water. Cosmetic wastewater Pump sum Equalization tank UASB Air blower Aerotank Settling tank Drying bed Water tank Receving water Figure 1: Diagram of treatment technology of the cosmetic WWTP Investigated parameters and sample collection methods To find the treatment performance of each system, these factors were investigated: COD (method SMEWW 5220 C-1995), BOD 5 (SMEWW 5210 B-1995), TSS (SMEWW 2540D-1995), ph (TCVN ). Here is the way to collect samples: 500 ml glass bottles were used to collect effluent sample from each stage of treatment. Duplicate samples were collected and stored in a refrigerator. After collection, all the samples were processed in Environmental Engineering Laboratory Institute of Environment and Resources, Vietnam National University-Ho Chi Minh city. 3. RESULTS AND DISCUSSION The analyzed results of wastewater from the WWTP of Vinacosmo company were described in Table 1. 2

3 Table 1: The characteristics of the influent and the effluent of the WWTP of Vinacosmo Co. Source: Green Tech Co., Feb 04, 2009 ph COD, mg/l BOD 5, mg/l Total suspended solids, mg/l Inlet 5, Wastewater after UASB 8, Effluent 7, Standard TCVN 5945:2005, B level 5, COD removal performance Figure 2 shows the COD removal performance of the cosmetic WWTP. The results of COD treatment are 47.8% và 96.35% after UASB and Aerotank, respectively. 3.2 BOD removal performance Hình 2: COD removal performance of the cosmetic WWTP % COD treated =(COD inffluent COD effluent )/COD inffluent 3

4 Figure 3: BOD removal performance of the cosmetic WWTP Figure 3 shows that the BOD removal performance of the cosmetic WWTP in Vinacosmo company is high and meets the required standard. In the WWTP, the treated BOD efficiency which is 96.34% after biological aerobic tank proves the correctness of our chosen technology. 3.3 Suspended solids removal performance Figure 4: SS removal performance of the cosmetic WWTP Similar to other investigated parameters, suspended solids were treated effectively in the cosmetic WWTP of Vinacosmo company. The SS removal performance of UASB is up to 78.6% and that of Aerotank is as high as 96.3%. Effluent meets the standard TCVN 5945:2005, level B. 4. CONCLUSIONS - All factors in the effluent of the WWTP meet the TCVN 5945:2005, B level. 4

5 REFERENCES B6-319 Ly Thuong Kiet, Ward 15, District11, HCMC Carr, Charles W. et al. Method for treatment & decolorization of wastewater from cosmetic manufacturing processes. US Patent ,