1School of Environmental Science and Technology, Hanoi University of Science and Technology; firstname.lastname@example.org
2Faculty of Environmental Sciences, University of Science, Vietnam National University, Hanoi; email@example.com
3Institute of Science and Technology – Ministry of Public Security; firstname.lastname@example.org
4Faculty of Environmental Engineering, National University of Civil Engineering; email@example.com
* Corresponding author: firstname.lastname@example.org; Tel.: +84–886114668
Sludge from wastewater treatment plants (WWTPs) in industrial park is currently a serious problem in Vietnam as well as many countries around the world. Unlike other by–products, sewage sludge from WWTPs contains a lot of toxic components, heavy metals, persistent organic substances and many other hazardous ingredients in high concentrations. Up to now, there has not been a Vietnamese study focusing on systematically assessing the level of toxic pollutants in industrial sludge in Vietnam. Therefore, this study focuses on evaluating the characteristics of industrial wastewater sludge in a specific industrial park, and thereby determining the characteristics and current status of heavy metal pollution in the sludge compared with agricultural soil samples. This study determined the heavy metals enrichments and their possible sources in industrial sludges from different sampling time. The results show that industrial sludge exhibits very high pollution for some typical heavy metals, especially Cu and Cd. The analysis of the correlation relationship between heavy metals also helps to identify the source of emission of heavy metals in the sludge sample. The PI, Igeo indexes are also 2–10 times higher than the control soil samples. In addition, the study also used citric acid, GLDA and ascorbic acid solutions as a method of heavy metal extraction from sludge with relatively high efficiency (~80%). Among the chelators, GLDA can be selected as the most effective removal with high capacity to remove Zn and Pb.
Cite this paper
Chung, N.T.; Ly, L.T.M.; Binh, N.X.; Chinh, P.M. Characteristics of Heavy Metal Pollution in Industrial Sludge and an Environmental–Friendly Removal Method. VN. J Hydrometeorol. 2022, 10, 1-10.
1. Islam, M.S.; Ahmed, M.K.; Raknuzzaman, M.; Habibullah–Al–Mamun, M.; Kundu, G.K. Heavy metals in the industrial sludge and their ecological risk: A case study for a developing country. J. Geochem. Explor. 2017, 172, 41–49.
2. Dung, T.T.T.; Cappuyns, V.; Vassilieva, E.; Golreihan, A.; Phung, N.K.; Swennen, R. Release of potentially toxic elements from industrial sludge: Implications for land disposal. Clean – Soil Air Water 2015, 43, 1327–1337.
3. Udayyanga, W.D.C.; Veksha, A.; Giannis, A.; Liang, Y.N.; Lisak, G.; Hu, X.; Lim, T.T. Insights into the speciation of heavy metals during pyrolysis of industrial sludge. Sci.Tot. Env. 2019, 691, 232–242.
4. Agoro, M.A.; Adeniji, A.O.; Adefisoye, M.A.; Okoh, O.O. Heavy Metals in Wastewater and Sewage Sludge from Selected Municipal Treatment Plants in Eastern Cape Province, South Africa, P2–3. Water 2020, 12(10), 2746.
5. Van Thinh, N.; Osanai, Y.; Adachi, T.; Vuong, B.T.S.; Kitano, I.; Chung, N.T.; Thai, P.K. Removal of lead and other toxic metals in heavily contaminated soil using biodegradable chelators: GLDA, citric acid and ascorbic acid. Chemosphere 2021 263, 127912.
6. McLaughlin, M.J.; Hamon, R.E.; McLaren, R.G.; Speir, T.W.; Rogers, S.L. A bioavailability–based rationale for controlling metal and metalloid contamination of agricultural land in Australia and New Zealand. Soil Res. 2000, 38(6), 1037–1086.
7. Tytla, M. Assessment of heavy metal pollution and potential ecological risk in sewage sludge from municipal wastewater treatment plant located in the most industrialized region in Poland – Case study. Int. J. Environ. Res. Public Health. 2019, 16(13), 2430.
8. Zhang, X.; Wang, X.Q.; Wang, D.F. Immobilization of Heavy Metals in Sewage Sludge during Land Application Process in China: A Review. Sustainability 2020 9(11), 2020.
9. Thai, N.T.K. Hazardous industrial waste management in Vietnam: current status and future direction. J. Mater. Cycles Waste Manag. 2009, 11, 258–262.
10. Strady, E.; Dinh, Q.T.; Némery, J.; Nguyen, T.N.; Guédron, S.; Nguyen, N.S.; Denis, H.; Phuoc Dan Nguyen, P.D. Spatial variation and risk assessment of trace metals in water and sediment of the Mekong Delta. Chemosphere 2017, 179, 367–378.
11. Nguyen, T.C.; Loganathan, P.; Nguyen, T.V.; Pham, T.T.N.; Kandasamy, J.; Wu, M.; Naidu, R.; Vigneswaran, S. Trace elements in road–deposited and waterbed sediments in Kogarah Bay, Sydney: enrichment, sources and fractionation. Soil Res. 2015, 53(4), 401–411.
12. Hung, C.V.; Cam, B.D.; Mai, P.T.N.; Dzung, B.Q. Heavy metals and polycyclic aromatic hydrocarbons in municipal sewage sludge from a river in highly urbanized metropolitan area in Hanoi, Vietnam: levels, accumulation pattern and assessment of land application. Env. Geochem. Health. 2015, 37, 133–146.
13. Viet, N.T.; Dieu, T.T.M.; Loan, N.T.P. Current status of sludge collection, transportation and treatment in Ho Chi Minh city. J. Env. Protect. 2013, 4(12), 1329-1335.
14. QCVN 50:2013/BTNMT – National technical regulation on hazardous thresholds for sludge from water treatment process.
15. QCVN 40:2011/BTNMT – National technical regulation on industrial wastewater.
16. APHA, AWWA, WEF – Standard Methods for the Examination of Water and Wastewater. 21st edition, Washington DC., USA. 2005, 1070–1072.
17. EPA Method 3050B (SW–846) Acid Digestion of Sediments, Sludges, and Soils. 2019.
18. Barbieri, M.; Nigro, A.; Sappa, G. Soil Contamination evaluation by enrichment factor (EF) and geoaccumulation index (Igeo). Senses. Sci. 2015, 2(3), 94–97.
19. Dung, T.T.T.; Golreihan, A.; Vassilieva, E. Insights into solid phase characteristics and release of heavy metals and arsenic from industrial sludge via combined chemical, mineralogical, and microanalysis. Env. Sci. Pollut. Res. 2015, 22, 2205–2218.
20. Vo, T.H.; Le, T.K.C.; Bui, X.T.; Nguyen, P.D. Assessment of decomposition and leaching ability of heavy metals in composting and aerobic sludge digestion. AUN/SEED – Net 2nd Regional Conference on Global Environment. Proceeding: “Global Environmental Issues for Sustainable Development in the ASEAN Region”, Kyoto, Japan, 2010.