Design a surface flow CWs to treat domestic wastewater for an residential area

Group 11 Đặng Minh Sơn Nguyễn Quang Văn Nguyễn Thanh Tùng Vũ Thị Thu Trang Content I Introduction II Designing 1.Domestic wastewater compositions 2.CWs calculation 3.Vegetation and Soil III Result IV Conclusion I Introduction Our topic: • Design a surface flow CWs to treat domestic wastewater of a residential area of 1000 people (Assume that person consume 150 lit water/day and wastewater amount is 80% of water supply)  We choose to use horizontal surface flow CW for this design Wastewater treatment by wetland • First made by ​ Seidel (1955) at the Max Planck Institute in Plon, Germany • Applied and developed countries in Europe, America, Australia in the years from 1970 to 2000 • Vietnam : that method was done at universities, research institutes in recent years and got some initial encouraging result  Most domestic wastewater in the residential urban, suburban and rural Vietnam are not handled properly  Wastewater from toilets only preliminary treatment, unsatisfactory discharge into the evironment has been mixed with waste water from the kitchen, bathroom, laundry cause pollution, the spread of diseases Free water surface (FWS) • These systems typically consist of basins or channels, with some sort of subsurface barrier toprevent seepage, soil or another suitable medium to support the emergent vegetation, and water at a relatively shallow depth flowing through the unit The shallow water depth, low flow velocity, and presence of the plant stalks and litter regulate water flow and, especially in long, narrow channels minimize short circuiting II Designing Domestic wastewater compositions CWs calculation Vegetation and Soil Domestic wastewater compositions Domestic wastewater contains BOD, SS, NH4+, Nitrogen, Phosphorus, Microorganisms… Table1: Typically polluted concentration and compositions Compositions Unit Amount pH - 6.5 - 8.5 BOD5 mg/l 250 – 400 COD mg/l 400 – 700 TSS mg/l 300 – 400 Total Nitrogen mg/l 60 Total Phosphorus mg/l 6.86 • Wastewater treating is in order to remove contaminants before discharging to the culverts or recycling • Water quality after treatment must satisfy the National technical regulation on domestic wastewater – QCVN 14:2008/BTNMT Compositions Unit Amount (influence) Co Amount (effluence) Ce pH - 6.5 - 8.5 5–9 - BOD5 mg/l 250 – 400 30 – 13 times higher COD mg/l 400 – 700 - - TSS mg/l 300 – 400 50 – times higher Total Nitrogen mg/l 60 30 - Total Phosphorus mg/l 6.86 - TSS can be easily removed  focus on BOD5 Table2: Value of maximum parameter allowed used for calculating in domestic wastewater Parameter Unit Concentration C A B pH - 5–9 5-9 BOD5 (20oC) mg/l 30 50 Total suspended solid (TSS) mg/l 50 100 Total dissolved solid (TDS) mg/l 500 1000 Sulfur (H2S) mg/l 1.0 4.0 Ammonium mg/l 10 Nitrate (NO3-) mg/l 30 50 Lipid mg/l 10 20 Surface active agents mg/l 10 10 Phosphate (PO43-) mg/l 10 11 Total Coliforms MPN/100 ml 3000 5000 A: for domestic supply purpose B: not for domestic supply purpose CWs calculation • Problem requirement: Design a surface flow CWs to treat domestic wastewater of a residential area of 1000 people (Assume that person consume 150 lit water/day and wastewater amount is 80% of water supply) BOD5 Removal in FWS Wetlands Ce = Ae Co −0.7 KT ( Av )1.75 As dn Q where, A = fraction of BOD5 not removed as settleable solids near headworks of the system (as decimal fraction) Av = specific surface area for microbial activity, m 2/m3 As = wetland treatment area, m2 d = design depth of system, m n = porosity of system (as a decimal fraction) Q = average hydraulic loading on the system, m3/day K T = temperature-dependent rate constant KT (in day-1) at water temperature T ( oC) Ce = Ae Co −0.7 KT ( Av )1.75 As dn Q  A sample calculation for the above coefficients equation yields the following results: • A = 0.52 • K20 = 0.0057 day-1 • Av = 15.7 m2/m3 • d = 0.6m (recommended) • n = Vv/V = 0.75 (Vv & V: volume of voids and total volume)  As= ? (m2)  Q = average hydraulic loading on the system, m3/day: Q = 1,000people x 150L/person/day x 80% =120,000L/day =120m3 /day  KT = K20 x (1.1)T-20 = 0.0057 day-1 x (1.1)25-20 = 9.2 x 10-3 Average ToC of water is 25oC K20 is rate constant at 20oC 50 = 0.52e Co −0.7×9.2×10 −3 ×15.71.75 × As ×0.6×0.75 120  As ranges from 320.67 m2 to 478.36m2 Assume, length : width = :  The length is about 32m ~ 38m  The width is about 10m ~ 13m Soil and Plant • Soil Permeability for Free Water Surface Systems • The most desirable soil permeability is 10-6 to 10-7m/s (0.14-0.014 in/hr) Sandy clays and silty clay loams can be suitable when compacted • Canna Hybrid: Strong growth at contaminated wetlands  good for NH4+, NO3-, PO43removal III Result For 1000 people: -Organic loading: < 112kg BOD5 -Hydraulic loading: 0.7-5.0 cm/day -Detention time: 5-15 days 20-30 cm Conclusion • In terms of social topics will contribute to improving the health of communities through clean water and create a good view from the technology underground leach plant • In terms of biodiversity conservation: Thread has created a good view and contribute to increase biodiversity in areas with abundant types of crops in the leach • In terms of economic and biodiversity: This type of model wastewater by biological treatment principle does not need to use energy saving will be very effective and economical when applied in practice than other methods In addition, the leach plant can be used as feed for livestock Treated water can circulate to bathe using pigs, barn wash or irrigate crops are good THANK YOU FOR LISTENING Nguyenloankhoamoitruong@gmail.com [...]... Nitrate (NO3-) mg/l 30 50 8 Lipid mg/l 10 20 9 Surface active agents mg/l 5 10 10 Phosphate (PO43-) mg/l 6 10 11 Total Coliforms MPN/100 ml 3000 5000 A: for domestic supply purpose B: not for domestic supply purpose 2 CWs calculation • Problem requirement: Design a surface flow CWs to treat domestic wastewater of a residential area of 1000 people (Assume that 1 person consume 150 lit water/day and wastewater. .. wastewater amount is 80% of water supply) BOD5 Removal in FWS Wetlands Ce = Ae Co −0.7 KT ( Av )1.75 As dn Q where, A = fraction of BOD5 not removed as settleable solids near headworks of the system (as decimal fraction) Av = specific surface area for microbial activity, m 2/m3 As = wetland treatment area, m2 d = design depth of system, m n = porosity of system (as a decimal fraction) Q = average hydraulic... This type of model wastewater by biological treatment principle does not need to use energy saving will be very effective and economical when applied in practice than other methods In addition, the leach plant can be used as feed for livestock Treated water can circulate to bathe using pigs, barn wash or irrigate crops are good THANK YOU FOR LISTENING Nguyenloankhoamoitruong@gmail.com ... 13m 3 Soil and Plant • Soil Permeability for Free Water Surface Systems • The most desirable soil permeability is 10-6 to 10-7m/s (0.14-0.014 in/hr) Sandy clays and silty clay loams can be suitable when compacted • Canna Hybrid: Strong growth at contaminated wetlands  good for NH4+, NO3-, PO43removal III Result For 1000 people: -Organic loading: < 112kg BOD5 -Hydraulic loading: 0.7-5.0 cm/day -Detention... time: 5-15 days 20-30 cm Conclusion • In terms of social topics will contribute to improving the health of communities through clean water and create a good view from the technology underground leach plant • In terms of biodiversity conservation: Thread has created a good view and contribute to increase biodiversity in areas with abundant types of crops in the leach • In terms of economic and biodiversity:... loading on the system, m3/day K T = temperature-dependent rate constant KT (in day-1) at water temperature T ( oC) Ce = Ae Co −0.7 KT ( Av )1.75 As dn Q  A sample calculation for the above coefficients equation yields the following results: • A = 0.52 • K20 = 0.0057 day-1 • Av = 15.7 m2/m3 • d = 0.6m (recommended) • n = Vv/V = 0.75 (Vv & V: volume of voids and total volume)  As= ? (m2)  Q = average... times higher 5 Total Nitrogen mg/l 60 30 - 6 Total Phosphorus mg/l 6.86 6 - TSS can be easily removed  focus on BOD5 Table2: Value of maximum parameter allowed used for calculating in domestic wastewater Parameter Unit Concentration C A B 1 pH - 5–9 5-9 2 BOD5 (20oC) mg/l 30 50 3 Total suspended solid (TSS) mg/l 50 100 4 Total dissolved solid (TDS) mg/l 500 1000 5 Sulfur (H2S) mg/l 1.0 4.0 6 Ammonium mg/l...• Wastewater treating is in order to remove contaminants before discharging to the culverts or recycling • Water quality after treatment must satisfy the National technical regulation on domestic wastewater – QCVN 14:2008/BTNMT Compositions Unit Amount (influence) Co Amount (effluence) Ce 1 pH - 6.5 - 8.5 5–9 - 2 BOD5 mg/l 250 – 400 30... hydraulic loading on the system, m3/day: Q = 1,000people x 150L/person/day x 80% =120,000L/day =120m3 /day  KT = K20 x (1.1)T-20 = 0.0057 day-1 x (1.1)25-20 = 9.2 x 10-3 Average ToC of water is 25oC K20 is rate constant at 20oC 50 = 0.52e Co −0.7×9.2×10 −3 ×15.71.75 × As ×0.6×0.75 120  As ranges from 320.67 m2 to 478.36m2 Assume, length : width = 3 : 1  The length is about 32m ~ 38m  The width is about