Effect of Hydraulic Retention Time on Pollutant Removal Performance of Biological Contact Oxidation Process Treating Hospital Wastewater

2014 ◽  
Vol 507 ◽  
pp. 725-729
Author(s):  
Bo Yu ◽  
Ying Zhou ◽  
Zheng Wen Huang ◽  
Li Chen
Keyword(s):  
Retention Time ◽  
Hydraulic Retention Time ◽  
Oxidation Process ◽  
Removal Rate ◽  
Pollutant Removal ◽  
Hospital Wastewater ◽  
Additional Processing ◽  
Contact Oxidation ◽  
Biological Contact Oxidation ◽  
Processing Steps

A study on hospital wastewater treatment was carried out using biological contact oxidation process. The effect of hydraulic retention time (HRT) on BOD5, CODCr and SS removal was investigated. The results showed that the removal rate of BOD5, and CODCr was ascending with the increase of HRT using the contrast test of five different HRTs. When the HRT was more than 4h, the effluent BOD5, CODCr could meet the discharge standard (GB18466-2005). In considering of raising the biodegradability of effluent, 4h was recommended in this study. However, the whole trend of SS variation of system was not obvious with the increase of HRT, and the effluent SS could not meet the discharge standard (20mg/L). Thus, the additional processing steps to remove SS would be necessary.

Removal of Total Coliform and TSS for Hospital Wastewater by Optimizing the Role of Typha Angustifolia and Fine Sand-Gravel Media in Horizontal Sub Surface Flow Constructed Wetland

2021 ◽  
Vol 12 (1) ◽  
pp. 20-31
Author(s):  
Abdul Gani Akhmad
Keyword(s):  
Retention Time ◽  
Hydraulic Retention Time ◽  
Fine Sand ◽  
Pilot Scale ◽  
Total Coliform ◽  
Surface Flow ◽  
Pollutant Removal ◽  
Typha Angustifolia ◽  
Hospital Wastewater

This study aims to evaluate the performance of a pilot-scale HSSF-CW utilizing Typha angustifolia and fine sand-gravel media in removing total coliform and TSS from hospital wastewater. Three pilot-scale HSSF-CW cells measuring 1.00 x 0.45 x 0.35 m3 were filled with gravel sand media with a diameter of 5 - 8 mm as high as 35 cm with a submerged media depth of 0.30 m. There were three treatments, namely the first cell (CW1) without plants, the second cell (CW2) was planted with a density of 12 Typha angustifolia plants, and the third cell (CW3) was planted with a density of 24 Typha angustifolia plants. The three HSSF-CW cells received the same wastewater load with total coliform and TSS contents of 91000 MPN / 100 mg and 53 mg / L, respectively, with Hydraulic Loading Rates 3,375 m3 per day. Wastewater was recirculated continuously to achieve the equivalent HSSF-CW area requirement. The experimental results show that the performance of CW3 is more efficient than CW1 and CW2 in total coliform and TSS removal for hospital wastewater. The pollutant removal efficiency at CW3 reached 91.76% for total coliform with one day hydraulic retention time and 81.00% for TSS with two days of hydraulic retention time. This study concludes that the HSSF-CW system using sand-gravel media with a diameter of 5 - 8 mm with a submerged media depth of 0.30 m and planted with Typha angustifolia with a tighter spacing proved to be more efficient in removing total coliform and TSS from hospital wastewater.

Novel application of bamboo-based fibers in a biological contact oxidation process

2014 ◽  
Vol 69 (7) ◽  
pp. 1534-1540 ◽  
Author(s):  
Xiaoming Zou ◽  
Yi Feng ◽  
Changming Sheng ◽  
Jia Liu ◽  
Lijun Lu ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Oxidation Process ◽  
Oxygen Demand ◽  
Specific Area ◽  
Pollutant Removal ◽  
Bamboo Charcoal ◽  
High Accumulation ◽  
Contact Oxidation ◽  
Biofilm Development ◽  
Biological Contact Oxidation

Generally, biofilm-supporting carriers in biological contact oxidation processes are made from thermoplastic polymers, which cause potential ecological damage because of the low biodegradation and high accumulation in organisms. Thus, four bamboo-based fibers, bamboo primitive fiber, bamboo fiber, bamboo charcoal fiber (BBF) and bamboo charcoal–cotton blending fiber (BCBF), were used as carriers and compared with two commercial carriers (vinylon (VY) and polypropylene (PP)) in a biological contact oxidation process system with the goal to develop a biodegradable and sustainable biofilm medium. Under steady state conditions, pollutants (chemical oxygen demand and NH4+-N) in stage 1 (days 1–29, hydraulic retention time (HRT) = 12 h) were efficiently removed with a removal efficiency ranging from 85 to 95%. In stage 2 (days 30–53, HRT = 4–12 h), the pollutant-removal efficiency of four reactors (BBF, BCBF, VY and PP) were nearly indistinguishable and were higher than the two other reactors, especially when the HRT was set at 4 h (days 46–53). Consequently, two optimized bamboo-based fibers (BBF and BCBF) can be developed as biofilm carriers for wastewater treatment in the future. Furthermore, studies demonstrated that the biofilm development difference showed good correlation with their specific area and relative oxygen content but not with their tenacity and antimicrobial activity.

Influence of High-Salinity Impact Load on an Integrated Sync Contact Oxidation Process

2014 ◽  
Vol 926-930 ◽  
pp. 396-399
Author(s):  
Peng Fei Yu ◽  
Ya Ting He ◽  
Jin Xiang Fu
Keyword(s):  
Hydraulic Retention Time ◽  
High Salinity ◽  
Oxidation Process ◽  
Impact Load ◽  
Effluent Water ◽  
Sludge Treatment ◽  
Salinity Shock ◽  
Contact Oxidation ◽  
Total Nitrogen Removal ◽  
Biological Contact Oxidation

To solve the problem of high-salt ballast wastewater treatment, biological contact oxidation process by combined packing used to simulate the experimental study. When dissolved oxygen is 5 to 6, water temperature is 18 ~ 20 °C, pH is 7~8 and hydraulic retention time is 48h, the Influence of salinity dips and swells process on sludge treatment system and its effects were investigated. The results showed that salinity shock loads on the system less affected COD removal, after 3-5 days short adaptability run, the system became able to restore effluent water stability. The influence of Salinity swells process on AOB, NOB and denitrifying bacteria was greater than a dip .Salinity plunged produced smaller impact on the total nitrogen removal, while in the salinity swells TN removal reduced from 70.7% to 42%.

scholarly journals UV-LED Combined with Small Bioreactor Platform (SBP) for Degradation of 17α-Ethynylestradiol (EE2) at Very Short Hydraulic Retention Time

Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 5960
Author(s):  
Oran Fradkin ◽  
Hadas Mamane ◽  
Aviv Kaplan ◽  
Ofir Menashe ◽  
Eyal Kurzbaum ◽  
...  
Keyword(s):  
Retention Time ◽  
Hydraulic Retention Time ◽  
Advanced Oxidation Process ◽  
Oxidation Process ◽  
Light Emission ◽  
Degradation Products ◽  
Secondary Effluent ◽  
Direct Photolysis ◽  
Indirect Photolysis ◽  
Uv Led

Degradation of 17α-ethynylestradiol (EE2) and estrogenicity were examined in a novel oxidative bioreactor (OBR) that combines small bioreactor platform (SBP) capsules and UV-LED (ultraviolet light emission diode) simultaneously, using enriched water and secondary effluent. Preliminary experiments examined three UV-LED wavelengths—267, 279, and 286 nm, with (indirect photolysis) and without (direct photolysis) H2O2. The major degradation wavelength for both direct and indirect photolysis was 279 nm, while the major removal gap for direct vs. indirect degradation was at 267 nm. Reduction of EE2 was observed together with reduction of estrogenicity and mineralization, indicating that the EE2 degradation products are not estrogens. Furthermore, slight mineralization occurred with direct photolysis and more significant mineralization with the indirect process. The physical–biological OBR process showed major improvement over other processes studied here, at a very short hydraulic retention time. The OBR can feasibly replace the advanced oxidation process of UV-LED radiation with catalyst in secondary sedimentation tanks with respect to reduction ratio, and with no residual H2O2. Further research into this OBR system is warranted, not only for EE2 degradation, but also to determine its capabilities for degrading mixtures of pharmaceuticals and pesticides, both of which have a significant impact on the environment and public health.

Research for Treating Avermectin Wastewater with UASB Technique

2011 ◽  
Vol 356-360 ◽  
pp. 1281-1284
Author(s):  
Yan Hong Chang ◽  
Hui Tao Feng ◽  
Hui Luo ◽  
San Jian Ma
Keyword(s):  
Retention Time ◽  
Hydraulic Retention Time ◽  
Removal Rate ◽  
Nitrogen Concentration ◽  
Ammonia Nitrogen ◽  
Cod Removal ◽  
Stable Phase ◽  
Volume Load ◽  
Cod Removal Rate

The avermectin wastewater was treated with UASB technique. The paper was focused mainly on the removal rate of COD and the change of ammonia nitrogen of influent and effluent wastewater in the first running stage. At the stable phase of anaerobic operation, the removal rate of COD could be stabilized at 85% when the influent volume load was 9.21 kg/(m3•d), and the effluent COD was about 1400 mg/L. As for ammonia nitrogen concentration of influent and effluent wastewater, in the first 50 days, the former was larger than the latter, after then, it was opposite. In the condition of same volume load but different hydraulic retention time (COD concentration of influent being different), COD removal rate kept almost the same. In the second running stage, the influent COD volume load reached 9.21 kg/(m3•d) at the 16th day, with the COD removal rate being around 87%.

Sign in / Sign up

Export Citation Format

Share Document