The paper indicates that Pistia stratiotes were used for wastewater treatment about twenty days with 0 individual/tank, five individuals/tank, seven individuals/tank, nine individuals/tank. Every experiment was conducted three times in the same way with 140 L for each tank. The experimental result shows that the amount of Pistia stratiotes increases and reach the highest quality in Treatment 3 on the 15th day.
AGU International Journal of Sciences – 2019, Vol (4), 33 – 38 THE USE OF PISTIA STRATIOTES IN DOMESTIC SEWAGE WATER TREATMENT FROM NATURAL LAKES AND PONDS AT KHANH AN COMMUNE, AN PHU DISTRICT, AN GIANG PROVINCE Nguyen Tran Thien Khanh1, Le Cong Quyen2, Nguyen Xuan Lan2 An Giang University, VNU – HCM Center for Natural Resources and Environment Monitoring and Technology, An Giang Information: Received: 25/04/2019 Accepted: 27/09/2019 Published: 11/2019 Keywords: Pistia stratiotes, domestic sewage, Khanh An lakes and ponds ABSTRACT The paper indicates that Pistia stratiotes were used for wastewater treatment about twenty days with individual/tank, five individuals/tank, seven individuals/tank, nine individuals/tank Every experiment was conducted three times in the same way with 140 L for each tank The experimental result shows that the amount of Pistia stratiotes increases and reach the highest quality in Treatment on the 15th day The treatment performance of BOD5, COD, TKN, and TP content of Treatment using Pistia stratiotes on the 20th day is high varying from 63.9 % to 96.4 % INTRODUCTION protein, 0,3% fat, 2,6% carbohydrate, 0,9% raw fiber and 1,9% mineral substances(mostly kali and phosphorus), the leaf is rich in vitamins A&C (Khare, C.P 2005) Mohapatra S.B and Patra A.K, (2014) concluded that P stratiotes Can be used as a main raw material in mixing feed for carp Today, Khanh An commune, An Phu district, An Giang province applies the method of digging pond to treat domestic wastewater with aquatic plants with an area of 600 m2 However, up to now, the domestic waste water from the pond after being discharged into the Hau River still exceeds QCVN 14: 2008 many times In order to provide more solutions to improve the water in Khanh An lake, it is necessary to study the density of Pistia stratiotes Sinha, S et al (2006) stated that Pistia stratiotes is a species capable of removing organic compounds in wastewater Nguyen Thanh Loc, Vo Thi Cam Thu et al (2015) showed that treatment performance of Pistia stratiotes for water quality parameters such as: TKN, TP, BOD5 and COD respectively at 65,5 % , 95,81%, 67,20% and 74,73% RESEARCH METHOD 2.1 Seedling preparation Pistia stratiotes collected from waterbody in An Giang province Pistia stratiotes seedling after collect is washed thoroughly with clean water Then choosing the strong, healthy plants, pest-free and relatively similar in height and growth period The roots will be cut, leaving Pistia stratiotes contains different types of alkaloids: glycosides, flavonoid and phytosterol Leaf and stem contain 1,4% 33 AGU International Journal of Sciences – 2019, Vol (4), 33 – 38 0.5 cm from the root and cut off the small seedlings The plants will be put into rectangular plastic containers containing clean water with a volume of 157.5 L (length 0.7 m x width 0.5 m x height 0.45 m) in days (Nguyen Thanh Loc et al., 2015) collected and analyzed according to standards APPA, AWWA and WEF (2005) The duration of collecting sampling period is days per time (the first time is from the beginning of experiment arrangement) Water samples are analyzed immediately after collection; In case of unsuccessful analysis, the sample will be stored in accordance to the standard of TCVN 6663-3 : 2008 2.2 Waste water preparation Wastewater is transported from Khanh An Lake to the testing location and immediately put into the testing units (transportation time is about hours) 2.4.2 Collecting and stratiotes samples analyzing Pistia Pistia stratiotes in all treatments were collected based on two indicators including density and number of leaves per individual The sampling period of Pistia stratiotes is the same as the water samples (Théophile Fonkou et al 2002) 2.3 Experimental arrangement The experiment was arranged in a completely randomized manner with treatments with different density of Pistia stratiotes densities: individual / tank, individuals / tank, individuals / tank, individuals / tank Each treatment was set up for times with the amount of waste water arranged in each tank of 140 L The experimental arrangement was 20 days (Théophile Fonkou et al 2002) No additional waste water was added during the experiment 2.5 Data processing methods The data was synthesized using MS Excel software First, the variance is analyzed then tested via Duncan using SPSS 18.0 software to evaluate the ability of water quality treatment indicators and the quantity of Pistia stratiotes in the experimental treatments 2.4 Method of collecting and analyzing indicators RESULTS AND DISCUSSION 2.4.1 Collecting and analyzing water samples 3.1 Characteristics of input waste water Water sample analysis criteria includes biological oxygen demand (BOD5), chemical oxygen demand (COD), Total Kjeldahl Nitrogen (TKN), Total phosphorus (TP) were The analysis of the input wastewater shows that the concentration of pollutants in the wastewater is quite high as shown in Table Table Characteristics of wastewater used in the experiment Indicator Unit Value QCVN 14:2008/BTNMT (Column A) BOD5 mg/L 105.67 ± 2.52 30 COD mg/L 206.33 ± 9.07 70* TKN mg/L 15.4 ± 0.3 35 TP mg/L 3.63 ± 0.13 (*) TCVN 6980: 2001, Q > 200 m3/s, F1 34 AGU International Journal of Sciences – 2019, Vol (4), 33 – 38 TKN and TP indicator respectively are 15.4 ± 0.3mg/L and 3.63 ± 0.13mg/L lower than QCVN 14:2008/BTNMT (Column A) However, BOD5, and COD indicators respectively are 105.67 mg/L, 206.33 ± 9.07mg/L much higher than allowed by law Therefore, the wastewater does not meet the standards and is required more treatment before being discharged and Treatment increases over time and reaches the highest value on the 15th day From the 15th to the 20th day, the number of Pistia stratiotes is decreasing This is due to the fact that the Pistia stratiotes starts to die at this stage because the nutrient content in water is very low while the quantity of Pistia stratiotes is high The difference in the number of Pistia stratiotes in the treatments is statistically significant at the significance level ( = 0.05) 3.2 Quantity growth of Pistia stratiotes The results in Figure show that the number of Pistia stratiotes in Treatment 1, Treatment Figure Growth in the quantity of Pistia stratiotes over time 3.3 Waste water treatment capacity of Pistia stratiotes 3.3.1 Meanwhile, control treatment does not arrange Pistia stratiotes, BOD5 content is at high level, exceeding QCVN 14: 2008 / BTNMT The content of BOD5 in different treatments was statistically significant ( = 0.05) The treatment performance of BOD5 content using Pistia stratiotes over time The results in Table show that BOD5 content decreases along with the experiment time All treatments using Pistia stratiotes to treat BOD5 content in water at day 20 was lower than QCVN 14: 2008 / BTNMT (column A) Treatment performance of BOD5 content in water in Treatment using Pistia stratiotes at day 20 was quite high: Treatment 1: 80.1%, Treatment 2: 84.2% and Treatment 3: 88% 35 AGU International Journal of Sciences – 2019, Vol (4), 33 – 38 Table BOD5 content of treatments over time (mg/L) Treatment Control Treatment1 Treatment2 Treatment3 Day Day Day 10 Day 15 Day 20 (*) (**) 105.7 ± 2.5 93.3 ± 1.5 82.3 ± 3.2 75.3 ± 1.5 68.0 ± 2.0 35.6 a a a a a 105.7 ± 2.5 86.3 ± 3.5 57.7 ± 1.2 37.3 ± 4.7 21.0 ± 2.7 a b b b b 105.7 ± 2.5 84.7 ± 3.8 55.3 ± 2.5 35.3 ± 2.3 16.6 ± 1.5 a b b b c 105.7 ± 2.5 74.7 ± 4.2 45.7 ± 2.9 31.0 ± 1.0 12.7 ± 2.1 a c c c d 80.1 84.2 30 88.0 Note: On the same column, values with different characters mean that the difference is statistically significant ( = 0.05); Average value ± Std (*): Treatment performance of day 20 (%) (**): QCVN 14:2008/BTNMT (Column A) 3.3.2 The treatment performance of COD content using Pistia stratiotes over time decomposed into an easily absorbed ion form for growth Table shows the COD content at the 15th day in Treatment 2, Treatment and the 20th day in treatments is lower than the permitted level of TCVN 6980: 2001, Q> 200 m3 / s, F1 and the wastewater is allowed to be discharged directly to the receiving source The results showed that Pistia stratiotes used organic matter to be The treatment performance of COD content in treatments using Pistia stratiotes on day 20 was quite high respectively Treatment1: 72%, Treatment2: 78.7% and Treatment3: 84.3% This result is quite similar to the study of Nguyen Thanh Loc et al (2015) and Théophile Fonkou et al (2002) Table COD values of treatments over time (mg/L) Treatment Control Treatment1 Treatment2 Treatment3 Day Day Day 10 Day 15 206.3 ± 9.1 190.3 ± 3.5 175.0 ± 4.6 159.0 ± 1.0 a a a a 206.3 ± 9.1 149.0 ± 6.1 a b 206.3 ± 9.1 140.7 ± 6.4 a b 206.3 ± 9.1 116.3 ± 4.0 a c 98.3 ± 5.7 b Day 20 (**) 145.0 ± 4.6 a 29.7 86.7 ± 2.1 57.7 ± 4.9 b 72.0 68.0 ± 1.0 44.0 ± 3.0 c 78.7 45.3 ± 1.5 32.3 ± 2.5 d 84.3 (*) b 82.3 ± 3.2 c c 55.7 ±2.5 d 70 d Note: On the same column, values with different characters mean that the difference is statistically significant ( = 0.05); Average value ± Std (*):Treatment performance of day 20 (%) (**): TCVN 6980: 2001, Q > 200 m3/s, F1 36 AGU International Journal of Sciences – 2019, Vol (4), 33 – 38 3.3.3 The treatment performance of TKN content using Pistia stratiotes over time at 71.1% On day 20, it is at 71.1% In Treatment 3, the number of Pistia stratiotes increases a lot TKN content treatment efficiency reaches the highest in Treatment at 83,6% This result is higher than stated in the study of Nguyen Thanh Loc et al., (2015) The difference in the ability of TKN content treatment of Pistia stratiotes in the treatments is statistically significant ( = 0.05) The data are shown in Table When comparing the results of the number of Pistia stratiotes in the Treatments, it shows that the amount of TKN content decreases, the weight of the Pistia stratiotes individuals increase along with the experiment time In particular, in Treatment 1, the number of Pistia stratiotes is the lowest, the treatment performance of TKN content of Treatment is Table TKN values of the treatments over time (mg/L) Treatment Control Day Day Day 10 Day 15 Day 20 (*) 15.4 ± 0.3 a 13.73 ± 0.2 a 12.47 ± 0.4 a 11.60 ± 0.2 a 10.57 ± 0.2 a 31.4 0.3 a 0.9 b 0.1 b 0.4 b 0.2 b 71.1 Treatment1 15.4 ± 10.66 ± 7.40 ± 5.70 ± 4.45 ± Treatment2 15.4 ± 0.3 a 10.47 ± 0.1 b 7.10 ± 0.2 b 5.31 ± 0.3 b 4.12 ± 0.3 b 73.2 Treatment3 15.4 ± 0.3 a 9.76 ± 0.3 c 6.52 ± 0.1 c 3.99 ± 0.1 c 2.52 ± 0.3 c 83.6 (**) 35 Note: On the same column, values with different characters mean that the difference is statistically significant ( = 0.05); Average value ± Std (*):Treatment performance of day (%) (*): QCVN 14:2008/BTNMT (column A) 3.3.4 The treatment performance of TP content using Pistia stratiotes over time the control treatment not using Pistia stratiotes, the treatment performance of TP content is only at 33.3% Thus, we conclude that aquatic plants take nutrients in wastewater to serve their growth and at the same time contributes to pollutants removal in the water The difference in the treatment performance of TKN content of Pistia stratiotes in the treatments is statistically significant ( = 0.05) Table shows the change in TP content in outlet wastewater compared to untreated input wastewater This proves that aquatic plants play an important role in phosphorus removal The treatment performance of TP content of Treatments with Pistia stratiotes at day 20 was very high Treatment 1: 63.9%, Treatment 2: 74.7% and Treatment 3: 96.4% Meanwhile, in 37 AGU International Journal of Sciences – 2019, Vol (4), 33 – 38 Table TP values of treatments over time (mg/L) Treatment Day Day Day 10 Day 15 Day 20 (*) Control 3.63 ± 0.13 a 3.24 ± 0.05a 2.86 ± 0.07a 2.56 ± 0.09a 2.42 ± 0.25a 33.3 Treatment1 3.63 ± 0.13 a 2.88 ± 0.12b 2.11 ± 0.08d 1.90 ± 0.15b 1.31 ± 0.18b 63.9 Treatment2 3.63 ± 0.13a 2.62 ± 0.13c 1.55 ± 0.17c 1.25 ± 0.03c 0.92 ± 0.12c 74.7 Treatment3 a d d d d 96.4 3.63 ± 0.13 2.16 ± 0.03 1.26 ± 0.09 0.80 ± 0.09 0.13 ± 0.04 (**) Note: On the same column, values with different characters mean that the difference is statistically significant ( = 0.05); Average value ± Std (*):Treatment performance of day 20 (%) (*): QCVN 14:2008/BTNMT (column A) CONCLUSION AND RECOMMENDATIONS Khare, C.P 2005 Encyclopedia of Indian medicinal plants Berlin Heidelberg, Germany: Springer-Verlag p 372 4.1 Conclusion Mohapatra S.B & Patra A.K (2014) Evaluation of nutritional value of water lettuce (pistia stratiotes) meal as partial substitution for fish meal on the growth performance of cyprinus carpio fry International Journal of Agricultural Science and Research (IJASR) ISSN(P): 2250-0057; ISSN(E): 2321-0087 Vol 4, Issue 3, Jun 2014, 147-154 The number of Pistia stratiotes increases over the experimental period and reached the highest number in Treatment on day 15 During the test, environmental factors decreases over time The treatment efficiency of BOD5 content in water in NT with Pistia stratiotes arrangement at day 20 is quite high respectively, Treatment 1: 80.1% to 88% The highest treatment performance of COD content in Treatment 3: 84.3% Treatment performance of TKN content ranges from 71.1% to 83.6% Finally, treatment performance of TP content is very high in Treatment 1: from 63.9% to 96.4% Treatment has the highest treatment performance Nguyen Thanh Loc, Vo Thị Cam Thu, Nguyen Truc Linh, Dang Cuong Thinh, Phung Thi Hang and Nguyen Vo Chau Ngan (2015) Evaluate the effectiveness of domestic wastewater treatment of some types of aquatic plants Can Tho University: Topic: Environment and climate change (2015): 119-128 4.2 Recommendations It is very important to continue to research domestic wastewater treatment in the lakes of Khanh An commune, An Phu district, An Giang province by Pistia stratiotes in continuous flow system Sinha, S., A.K Gupta, K Bhatt, K Pandey, U.N Rai and K.P.Singh (2006) Environ Monitor Assess., 80: 17-31 Théophile Fonkou, Philip Agendia, Ives Kengne, Amougou Akoa & Jean Nya, (2002) Potentials of water lettuce (Pistia stratiotes) in domestic sewage treatment with macrophytic lagoon systems in Cameroon Proceedings of International Symposium on Environmental Pollution Control and Waste Management 7-10 January 2002, Tunis (EPCOWM’2002), p.709-714 REFERENCES APHA, AWWA & WEF (2005) Standard Methods for the Examination of Water and Wastewater (20th ed), American Public Health Association, Washington, DC 38 ... wastewater treatment in the lakes of Khanh An commune, An Phu district, An Giang province by Pistia stratiotes in continuous flow system Sinha, S., A.K Gupta, K Bhatt, K Pandey, U.N Rai and K.P.Singh... evaluate the ability of water quality treatment indicators and the quantity of Pistia stratiotes in the experimental treatments 2.4 Method of collecting and analyzing indicators RESULTS AND DISCUSSION... (column A) Treatment performance of BOD5 content in water in Treatment using Pistia stratiotes at day 20 was quite high: Treatment 1: 80.1%, Treatment 2: 84.2% and Treatment 3: 88% 35 AGU International