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Water Pollutants and Water Pollution
Published in Stanley E. Manahan, Environmental Chemistry, 2022
Excessive levels of ammoniacal nitrogen cause water-quality problems. Ammonia is the initial product of the decay of nitrogenous organic wastes, and its presence frequently indicates the presence of such wastes. It is a normal constituent of low-pE groundwaters and is sometimes added to drinking water as an aid to disinfection, where it reacts with chlorine to provide residual chlorine (see Section 7.11). Since the pKa of ammonium, NH4+, is 9.26, most ammonia in water is present as NH4+ rather than as NH3 .
Water Pollutants and Water Pollution
Published in Stanley Manahan, Environmental Chemistry, 2017
Excessive levels of ammoniacal nitrogen cause water-quality problems. Ammonia is the initial product of the decay of nitrogenous organic wastes, and its presence frequently indicates the presence of such wastes. It is a normal constituent of low-pE groundwaters and is sometimes added to drinking water as an aid to disinfection, where it reacts with chlorine to provide residual chlorine (see Section 7.11). Since the pKa of ammonium ion, NH4+, is 9.26, most ammonia in water is present as NH4+ rather than as NH3.
Biological nitrification in a batch gas–liquid–solid bioreactor
Published in Shirish H. Sonawane, Y. Pydi Setty, T. Bala Narsaiah, S. Srinu Naik, Innovative Technologies for the Treatment of Industrial Wastewater, 2017
P. B. N. Lakshmi Devi, Y. Pydi Setty
Ammonia is the most commonly occurring nitrogenous pollutant in wastewater. Municipal sewage, agricultural and industrial wastewater are the main sources of ammoniacal nitrogen. The main polluting industrial sources of ammoniacal nitrogen include oil refineries, coal gasification units, dairy industry, distilleries, fertilizer and pharmaceutical industries, glass production units, cellulose, pulp and paper industries. European Association has given approximately 0.5 mg/L as maximum limit of ammonia for drinking water and guide level is given as 2.5 and 1.0 mg/L for discharge to surface waters and wells, respectively according to Iran Environmental Protection Agency (IEPA) [16,36]. It causes irritation to eyes, skin and respiratory problems to human beings as well as animals.
Assessment of surface water quality of the bois river (Goiás, Brazil) using an integrated physicochemical, microbiological and ecotoxicological approach
Published in Journal of Environmental Science and Health, Part A, 2022
Samara Silva Soares, Gessyca Gonçalves Costa, Lara Barroso Brito, Gisele Augusto Rodrigues de Oliveira, Paulo Sérgio Scalize
In P3, ammoniacal nitrogen concentration (2.26 mg/L) is above the reference value, but this level did not cause toxicity to zebrafish embryos and larvae. The total ammoniacal nitrogen consists of two distinct forms of ammonia: NH3 (unionized ammonia) and NH4+ (ionized ammonia). The NH3 is considered the most toxic form for aquatic organisms, especially fish since it crosses freely through their gills.[40] However, the toxic effects of ammonia on the initial stages of fish are not fully understood, and little is known about the effects on the sensory system.[41] The proportion between NH3 and NH4+ is dependent on pH, temperature, and salinity.[42] An increase in pH favors the formation of NH3, while a decrease favors the ionized form (NH4+). Temperature also affects the toxicity of ammonia to aquatic life.[43] Ammonia can enter the aquatic environment via anthropogenic sources such as domestic effluent discharges and agricultural runoff or natural sources such as nitrogen fixation and the excretion of nitrogenous wastes from animals.[44]
Industrial wastewater treatment using magnesium electrocoagulation in batch and continuous mode
Published in Journal of Environmental Science and Health, Part A, 2020
Perla Fabiola Carmona-Carmona, Ivonne Linares-Hernández, Elia Alejandra Teutli-Sequeira, Boris Miguel López-Rebollar, Carolina Álvarez-Bastida, Miroslava de los Angeles Mier-Quiroga, Guadalupe Vázquez-Mejía, Verónica Martínez-Miranda
Two different samples were characterized for batch and continuous tests (Table 2). In the batch system, the main parameters were color 3,999.42 Units Pt-Co, COD 1,288.59 mg/L, and BOD 408.17 mg/L. The samples had low biodegradability indexes (BI) of 0.31, which indicates that the effluent contained persistent organic matter with low biodegradability. The COT value was 559.58 mg/L, and the total solids content was 6,222.67 mg/L, of which 3,613 mg/L was volatile organic matter (TVS) and 2627 mg/L corresponded to total dissolved solids and salts. The sedimentable solids were 166 mL/L. The wastewater had high alkalinity (1,437.33 mg/L CaCO3), a pH of 7.6, chlorides 388.77 mg/L, and sodium 443 mg/L, thus favoring the electrical conductivity in the electrochemical cell and avoiding the need for electrolyte support. The presence of high concentrations of nitrogen and phosphate could cause eutrophication in water; in this sample, total phosphorus concentrations of 1,692.41 mg/L, ammoniacal nitrogen of 46 mg/L, nitrites of 5.40 mg/L, and nitrates of 20 mg/L were determined. The sample contained a hardness of 233.33 mg/L CaCO3, calcium, and magnesium about 30 mg/L of both cations, which is insufficient to precipitate the high content of phosphate, sulfate ions, and alkalinity present.
Coagulation/Fenton oxidation combined treatment of compost leachate using quince seed mucilage as an effective biocoagulant
Published in Environmental Technology, 2021
Fatemeh Kanaani, Babak Tavakoli, Ali Reza Pendashteh, Naz Chaibakhsh, Fariba Ostovar
The samples were collected during a 3-month period (Summer 2017) from the Rasht Compost Plant located at Guilan province, Iran. The collected samples were sent to the laboratory, stored at 4°C and analyzed within two days according to the standard methods [22]. COD was determined by the closed reflux method. Turbidity was measured by a turbidity meter (TU-2016, Taiwan). The ammoniacal nitrogen concentration was measured by the Nessler method (Jenway spectrophotometer, England). A Shimadzu AA-670 flame atomic absorption spectrophotometer (FAAS) was applied for the determination of heavy metals. The characteristics of the raw compost leachate is presented in Table 1.