Analysis of wastewater toxicity and detoxification during their biological treatment
Abstract
The analysis of active sludge capacity changes and the level of wastewater toxicity in the process of biological treatment at urban wastewater treatment plants was carried out. The ability of active sludge to bind the synthetic surface active substance (SSAS) sodium laurethsulfate and heavy metals: Fe(total), Cu2+, Сr6+ and also to decrease the level of waste water toxicity were considered. The ability of active sludge to bind laurethsulfate was 8 times higher than that of activated carbon. SSAS was more dangerous in the micellar than in the molecular form. The combined presence of Fe(total) with SSAS as ferrum laurethsulfate reduced its lethal dose in 1,5 times. Fe(total), Cu2+, ions, than Сr6+. When studying the properties of used activated sludge, it was found that it has a sufficiently high sorption capacity for Fe(total), Cu2+, Сr6+ ions. The important role of the biosorption properties of activated sludge in the detoxification of wastewater is shown and possible reasons for changes in the toxicity index and the binding capacity of heavy metals in the activated sludge regenerator and along the corridors of the aeration tank are discussed. The obtained data indicate that the combination of activated sludge regeneration and detoxification processes in the aeration tank is a disadvantage of the traditional wastewater bio-treatment scheme. It is indicated that the regeneration or detoxification of returnable activated sludge outside the aeration tank will reduce the level of toxic substances in it and improve the safety of wastewater treatment.
References
Zhmur, N.S. (2003). Technological and biochemical processes of wastewater treatment at facilities with aeration tanks. M.: AKVAROS (in Russ.).
Kuznetsov, A.E. (2010). Applied ecobiotechnology: in 2 volumes. M.: BINOM: Laboratory of Knowledge (in Russ.).
Pakhnenko, E.P. (2013). Sewage sludge and other non-traditional organic fertilizers: M.: BINOM: Laboratory of Knowledge (in Russ.).
Wastewater pollution by heavy metals and their salts. OOO «Olbest», 2000 – 2018. https://otherreferats.allbest.ru/ ecology/00813134_0.html. (accessed 10.01.2020) (in Russ.).
Ignatenko, A.V. (2015). Biosorption-biocoagulation detoxification of wastewater by active sludge. Trudy BGTU, 4(177), 262‒266 (in Russ.).
Sazanoves, M.A., & Ignatenko, A. V. (2014). Detoxication analysis of aquatic environment with biological testing method. Proceedings of BSTU. Chemistry, Technology of organic matter and Biotechnology. (4), 162–165 (in Russ.).
ER F 12.15.1-08. Methodical instructions on sampling for wastewater analysis. M.: FBU FTsAO, 2015 (in Russ.).
ER F 14.1:2:4.254-2009. Procedure of measuring mass concentrations of suspended substances and calcined suspended substances in samples of drinking, natural and waste water by gravimetric method. M.: FBU FTsAO, 2012 (in Russ.).
GOST (State Standard) 26713-85. Organic fertilizers. Method for determining moisture and dry residue. Moscow: Publishing House of Standards Organic fertilizers. Method for determining moisture and dry residue. M.: Izd-vo standartov. 2019 (in Russ.).
Ignatenko, A.V. (2018). Sample preparation and biotesting toxicity of sewage sludge wastes. Khimicheskaya bezopasnost' = Chemical Safety Science, 2(2). 251–271. https//:10.25514/CHS.2018.2.14120 (in Russ.).
ER F 14.1:2:4.50-96. Method of measuring the mass concentration of total iron in drinking, surface and wastewater by the photometric method with sulfosalicylic acid. M.: FBU FTsAO, 2011 (in Russ.).
ER F 14.1:2:4.48-96. Method of measuring the mass concentration of copper ions in drinking, surface and wastewater by photometric method with lead diethyldithiocarbamate. M.: FBU FTsAO, 2011 (in Russ.).
BNS 17.13.05-33-2014. Environmental protection and environmental management. Analytical control and monitoring. Water quality. Determination of the concentration of chromium (VI) and total chromium in water by photometric method with diphenylcarbazide. Izdanie ofitsi-al'noe:– Vved. 28.04.14. – Minsk: Goskomitet po standartizatsii RB, 2014 (in Russ.).
Ignatenko А.V., & Masekhnovich А.А. (2021). Biosorption, biocoagulation properties of activated sludge and changes in the toxicity of wastewater during their biological treatment. Trudy BGTU. Seriya 2. (1), 63–68 (in Russ.).
Ignatenko, A.V. (2020). Express method for sample preparation and sewage sludge waste toxicity biotesting. Khimicheskaya bezopasnost' = Chemical Safety Science, 4(1), 80–96. (in Russ.). https://doi.org/10.25514/CHS.2020.1.17005
Resolution of the Ministry of Natural Resources and Environmental Protection of the Republic of Belarus on May 26, 2017 No. 16 "On some issues of rationing of discharges of chemical and other substances in the composition of wastewater». Natsional'nyy pravovoy Internet-portal Respubliki Belarus', 21.06.2017, 8/32141 (in Russ.).
Shashkina, P.S., Dedkov, Yu.M. (2010). Assessment of sorption capabilities of river suspended solids of different genesis. Vestnik Moskovskogo gosudarstvennogo oblastnogo universiteta. Р. 65–70 (in Russ.).
Hygienic Standard 2.1.5.1315-03. MPC of chemical substances in water of water bodies of economic-drinking and cultural-household water use. M.: Standartinform, 2003. (in Russ.).
Dregulo, A. M. (2014). Problems of ecological and chemical detoxification of activated sludge and its use in biological wastewater treatment (Ph.D. dissertation). Saint-Petersburg: Falcon Print (in Russ.).
Klimov, E.S., & Buzaeva, M.V. (2011). Natural sorbents and complexones in wastewater treatment. Ulyanovsk: UlSTU (in Russ.).
Hofman, A. F., & Small, D. M. (1967). Detergent properties of bile salts: correlation with physio-logical functions. Annu. Rev. Med., 18, 333–376.
Zapol'skiy, A.K., & Baran, A.A. (1987). Coagulants and flocculants in water purification processes. L.: Khimiya (in Russ.).
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