Investigation into the implementation of chloramination at Sedibeng Water

2003 ◽  
Vol 3 (1-2) ◽  
pp. 233-238
Author(s):  
N. Basson ◽  
D. Traut ◽  
G. Titus ◽  
C. vd Walt ◽  
J. Haarhoff

The Balkfontein and Virginia plants of Sedibeng Water, situated in the Free State Province of South Africa, treat water for potable purposes. Chlorine is used as disinfectant at both plants. Low levels of free chlorine measured in the water supplied from some reservoirs, logistics and costs, related to the application of chlorination at various points in the distribution system, were the main thrusts for an investigation into the use of chloramination as an alternative means of disinfection. The so-called contact time (CT)-approach from the United States Environmental Protection Agency was applied for the evaluation of disinfection efficiency. The distribution system was modelled by using a hydraulic computer system. Decay rates for both chlorine and monochloramine - a vital parameter for eventual determination of the amount of chlorine and ammonia to be dosed - were determined. The levels of disinfectant in the water at a specific location could be predicted by using the decay values. The main findings of this investigation are that chloramination is an attractive and cost-effective alternative for conventional chlorination for providing quality assurance to all. It is estimated that the capital layout will be recovered within one year of operation of the ammoniation system.

Author(s):  
W E Short II

The chemical and petrochemical industries have decades of experience in specifying metallic piping lined with non-metals as a cost effective alternative to high-priced alloy materials of construction for piping in corrosive service. Early on, application of plastic piping was essentially limited to atmospheric chemical sewage service and to above-ground vents and drains. However, applications and usage of plastic piping continue to increase as engineers become more confident in specifying plastic materials and mechanical contractors gain experience with their installation. Non-metallic materials are being developed that are not only corrosion resistant but also have increasingly higher pressure and temperature capabilities. Plastic double-containment piping has experienced tremendous growth for handling hazards and toxic fluids. In the United States, recent dramatic growth of plastic double-containment piping applications has been, to a large extent, for compliance with the Environmental Protection Agency (EPA) regulations of the 1976 Resource Conservation and Recovery Act (RCRA). Related EPA regulatory efforts were accelerated in 1988 by more stringent amendments to this legislation. Industry in the United States must comply with these EPA regulations by December 1998. Plastic piping and metallic piping lined with non-metals have been covered to some extent by the ASME B31.3 Chemical Plant and Petroleum Refinery Piping Code for several years. The distinctive requirements of non-metallic piping and piping lined with non-metals were incorporated into the 1980 edition as a separate Chapter VII, which is dedicated to this growing area of interest in piping. This paper provides an overview of the present coverage of non-metallic piping lined with non-metals in the ASME B31.3 Chemical Plant and Petroleum Refinery Piping Code (1). Some topics that warrant further investigation are presented as well.


1990 ◽  
Vol 22 (12) ◽  
pp. 239-247
Author(s):  
Philip Wolstenholme

To prepare dried municipal sludge material for use by the fertilizer industry, Ocean County Utilities Authority, New Jersey needed a process to increase the size of their sludge particles to between 1 and 3 millimetres. Several processes were evaluated during the planning and design phases of the project. The most cost-effective and reliable process was pressure agglomeration by compaction with a roll press, followed by granulation and screening of the compacted material. This process was tested with a sample of the Authority's digested sludge, which had been dried in a laboratory-scale evaporator. Fullscale compaction and granulation test equipment was used at a laboratory in West Germany to confirm the feasibility of the process and to develop data for the design of the project. As a result of its “innovative” approach to sludge processing, the United States Environmental Protection Agency (EPA) qualified this $60 million project for special funding. The project is nearing construction completion and due to be commissioned in spring of 1990.


2020 ◽  
Vol 21 (9) ◽  
pp. 3317
Author(s):  
Efstratios Nikolaivits ◽  
Andreas Agrafiotis ◽  
Eirini Baira ◽  
Géraldine Le Goff ◽  
Nikolaos Tsafantakis ◽  
...  

2,4-Dichlorophenol (2,4-DCP) is a ubiquitous environmental pollutant categorized as a priority pollutant by the United States (US) Environmental Protection Agency, posing adverse health effects on humans and wildlife. Bioremediation is proposed as an eco-friendly, cost-effective alternative to traditional physicochemical remediation techniques. In the present study, fungal strains were isolated from marine invertebrates and tested for their ability to biotransform 2,4-DCP at a concentration of 1 mM. The most competent strains were studied further for the expression of catechol dioxygenase activities and the produced metabolites. One strain, identified as Tritirachium sp., expressed high levels of extracellular catechol 1,2-dioxygenase activity. The same strain also produced a dechlorinated cleavage product of the starting compound, indicating the assimilation of the xenobiotic by the fungus. This work also enriches the knowledge about the mechanisms employed by marine-derived fungi in order to defend themselves against chlorinated xenobiotics.


Separations ◽  
2020 ◽  
Vol 7 (1) ◽  
pp. 3 ◽  
Author(s):  
Benigno José Sieira ◽  
Inmaculada Carpinteiro ◽  
Rosario Rodil ◽  
José Benito Quintana ◽  
Rafael Cela

An analytical method based on high-resolution quadrupole–time-of-flight (QToF) mass spectrometry has been developed as an alternative to the classical method, using a low-resolution ion trap (IT) analyzer to reduce interferences in N-nitrosamines determination. Extraction of the targeted compounds was performed by solid-phase extraction (SPE) following the United States Environmental Protection Agency (USEPA) -521 method. First, both electron impact (EI) and positive chemical ionization (PCI) using methane as ionization gas were compared, along with IT and QToF detection. Then, parameters such as limits of detection (LOD) and quantification (LOQ), linearity, and repeatability were assessed. The results showed that the QToF mass analyzer combined with PCI was the best system for the determination of the N-nitrosamines, with instrumental LOD and LOQ in the ranges of 0.2–4 and 0.6–11 ng mL−1, respectively, which translated into method LOD and LOQ in the ranges of 0.2–1.3 and 0.6–3.9 ng L−1, respectively. The analysis of real samples showed the presence of 6 of the N-nitrosamines in influent, effluent, and tap water. N-nitrosodimethylamine (NDMA) was quantified in all the analyzed samples at concentrations between 1 and 27 ng L−1. Moreover, four additional nitrosamines were found in tap and wastewater samples.


2018 ◽  
Vol 8 (3) ◽  
pp. 415-428 ◽  
Author(s):  
Kuitakwashe Nhongo ◽  
Zvikomborero Hoko ◽  
Jameson Kugara

Abstract Formation of disinfectant by-products was investigated in the Harare water supply system from February to April 2015. Sampling sites were selected from the lake, Morton Jaffray Water Treatment Works and critical points in the distribution system. The spatial variations of trihalomethanes and selected water quality parameters were investigated for 15 sampling points in 5 sampling campaigns to assess suitability for drinking. All trihalomethane species were measured, namely chloroform, bromodichloromethane, dibromochloromethane and bromoform. Only chloroform and bromodichloromethane were detected. The study confirmed that there is trihalomethanes formation in the Harare water distribution system and that it is affected by the residence time and presence of organic matter in the system. However, the levels of trihalomethanes are generally within the levels suggested by the World Health Organization. Only bromodichloromethane presents a risk for long-term exposure as it had levels that exceeded the limit for long-term exposure suggested by the United States Environmental Protection Agency. Bromodichloromethane, turbidity and free residual chlorine levels were not suitable for drinking in some of the zones. Boosting of chlorine residuals is necessary especially in areas with free chlorine less than 0.2 mg/L. Injection of ammonia, periodic cleaning of storage reservoirs, and flushing of lines will reduce trihalomethanes formation.


Molecules ◽  
2020 ◽  
Vol 25 (8) ◽  
pp. 1815 ◽  
Author(s):  
Aleksandra Ukalska-Jaruga ◽  
Karolina Lewińska ◽  
Elton Mammadov ◽  
Anna Karczewska ◽  
Bożena Smreczak ◽  
...  

The aim of this study was to identify and examine the levels of organochlorine pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) in soil collected from the surroundings of historical pesticide storage facilities on former agricultural aerodromes, warehouses, and pesticide distribution sites located in the most important agricultural regions in Azerbaijan. The conducted research included determination of three groups of POPs (occurring together), in the natural soil environment influenced for many years by abiotic and biotic factors that could have caused their transformations or decomposition. In this study, soil samples were collected in 21 georeferenced points located in the administrative area of Bilasuvar, Saatly, Sabirabad, Salyan and Jalilabad districts of Azerbaijan. Soil chemical analysis involved determination of organochlorine compounds (OCP): hexachlorocyclohexanes (HCHs) (three isomers α-HCH, β-HCH and γ-HCH) and dichlorodiphenyltrichloroethanes (DDTs) (six congeners 2,4′DDT; 4,4′DDT; 2,4′DDE; 4,4′DDE; 2,4′DDE; and 4,4′DDE); polycyclic aromatic hydrocarbons (PAHs): 16 compounds from the United States Environmental Protection Agency US EPA list and, PCBs (seven congeners identified with the following IUPAC numbers: 28, 52, 101, 118, 138, 153, and 180). Our research showed that OCPs reached the highest concentration in the studied areas. The total concentrations of OCPs ranged from 0.01 to 21,888 mg∙kg−1 with significantly higher concentrations of Σ6DDTs (0.01 μg kg−1 to 21880 mg kg−1) compared to ΣHCH (0.14 ng kg−1 to 166.72 µg kg−1). The total concentrations of PCBs in the studied soils was varied from 0.02 to 147.30 μg·kg−1 but only PCB138 and PCB180 were detected in all analyzed samples. The concentrations of Σ16 PAHs were also strongly diversified throughout the sampling areas and ranged from 0.15 to 16,026 mg kg−1. The obtained results confirmed that the agricultural soils of Azerbaijan contained much lower (up to by three orders of magnitude) concentrations of PCBs and PAHs than DDT. It is supported by the fact that PCBs and PAHs were not directly used by agriculture sector and their content results from secondary sources, such as combustion and various industrial processes. Moreover, the high concentrations of PAHs in studied soils were associated with their location in direct neighborhood of the airport, as well as with accumulation of contaminants from dispersed sources and long range transport. The high concentrations of pesticides confirm that deposition of parent OCPs have occurred from obsolete pesticide landfills.


Author(s):  
Yadong Kong ◽  
Ping Lu ◽  
Tao Yuan ◽  
Jinghui Niu ◽  
Zhaoji Li ◽  
...  

Swimming in surface water bodies (e.g., lakes, rivers) can expose the human body to substantial risk of infection by Cryptosporidium. These findings are from a one-year investigation on the occurrence and distribution of the protozoan parasite Cryptosporidium in Yunlong Lake, Xuzhou, China. Cryptosporidium oocysts were detected by immunofluorescence microscopy. From January to November of 2015, 180 samples (120 water samples and 60 sediment samples) were collected and analyzed. Among them, 42 (35%) water samples and 28 (47%) sediment samples tested positive for Cryptosporidium. The concentration of Cryptosporidium oocysts in the water samples was 0–8/10 L and 0–260/g in sediment samples. Results revealed that July was the highest risk period for both swimming and diving with an estimated probability of infection from swimming of greater than 18 per 10,000 swim sessions. It was concluded that swimming or diving in Yunlong Lake has a higher risk of Cryptosporidium infection than the acceptable risk level set by the United States Environmental Protection Agency. Thus, regular monitoring of water quality in recreation water bodies is strongly recommended.


Author(s):  
Leslie J. Jardine ◽  
Georg B. Borisov ◽  
Sergey I. Rovny ◽  
Konstantin G. Kudinov ◽  
Alexander A. Shvedov

Abstract The Mayak Production Association (PA Mayak), an industrial site in Russia, will be assigned multiple new plutonium disposition missions in order to implement the Agreement Between The Government Of The United States Of America And The Government Of Russian Federation Concerning The Management And Disposition Of Plutonium Designated As No Longer Required For Defense Purposes And Related Cooperation signed September 1, 2000, by Gore and Kasyanov, In addition, the mission of industrial-scale mixed-oxide (MOX) fabrication will be assigned to either the Mining Chemical Combine (MCC) industrial site at Krasnoyarsk-26 (K-26) or PA Mayak. Over the next decades, these new missions will generate radioactive wastes containing weapons-grade plutonium. The existing Mayak and K-26 onsite facilities and infrastructures cannot currently treat and immobilize these Pu-containing wastes for storage and disposal. However, the wastes generated under the Agreement must be properly immobilized, treated, and managed. New waste treatment and immobilization missions at Mayak may include operating facilities for plutonium metal-to-oxide conversion processes, industrial-scale MOX fuel fabrication, BN-600 PAKET hybrid core MOX fuel fabrication, and a plutonium conversion demonstration process. The MCC K-26 site, if assigned the industrial-scale MOX fuel fabrication mission, would also need to add facilities to treat and immobilize the Pu-containing wastes. This paper explores the approach and cost of treatment and immobilization facilities at both Mayak and K-26. The current work to date at Mayak and MCC K-26 indicates that the direct immobilization of 1.6 MT of weapons-grade plutonium is a viable and cost-effective alternative.


1997 ◽  
Vol 80 (6) ◽  
pp. 1229-1234 ◽  
Author(s):  
Peter M Scott ◽  
Guillaume A Lawrence

Abstract Aflatoxins B1, B2, G1, and G2 were determined at parts-per-trillion levels in beer by immunoaffinity column cleanup and reversed-phase liquid chromatography (LC) with fluorescence detection after trifluoroacetic acid derivatization. Silanized vials were necessary for the evaporation step in order to obtain good recoveries of aflatoxins from spiked beer samples. Recoveries averaged 90–104%, 94%, 84–87%, and 89% for aflatoxins B1, B2, G1, and G2, respectively, at levels of 9.7–133 ng B1, 46 ng B2, 35–140 ng G1 and 41 ng G2/L. Detection limits were 19–20 ng/L for aflatoxins B1 and G1 and 15–16 ng/L for aflatoxins B2 and G2 (signal-to-noise ratio = 3:1) obtained by using an excitation wavelength of 360 nm; at 340 nm these detection limits were lowered to about 2 ng/L. Analysis of 24 beer samples, the majority from the United States and Mexico, showed natural contamination of one sample of Mexican beer at 49 ng B1/L when determined at 360 nm excitation, but reanalysis of 23 of the samples using 340 nm excitation indicated that an additional 4 Mexican samples and one Brazilian sample contained anatoxin B1 at low levels (< 10 ng/L).


1981 ◽  
Vol 1981 (1) ◽  
pp. 655-660
Author(s):  
J. H. Nash ◽  
M. G. Johnson

ABSTRACT The United States Environmental Protection Agency (EPA) Oil and Hazardous Materials Simulated Environmental Test Tank (OHMSETT) has designed a wide variety of water jet applications for control of spilled oil. This latest study reveals the advantage of using a simple nozzle consisting of a standard pipe mounted to produce a coherent vertical jet of water downward. Examples are illustrated with test data for several cost effective, field erectable systems using standard available water pumps and hardware. One system uses a series of jets to converge a 4.5-meter wide, 1-millimeter thick slick to 0.6 meter wide by 8 millimeters thick, moving at 6 knots in waves. The report reviews experience and test data obtained With a small barge, weir-type skimmer, mounted on a diverting inflatable boom system. This can be used to simulate the new USCG-ZRV fast current skimmer, the Bennett advancing belt skimmer, the U.S. Navy offshore spill tests, and dock simulations with the OHMSETT main bridge. Advancing skimmers may use the water jet boom system for three reasons. First, it allows an encounter width wider than the skimmer. Next, it will cause a thin slick to become thicker, thereby possibly allowing the skimmer oil pickup techniques to be more efficient. A water jet system can be used to couple a boom-towed skimmer and prevent skirt losses at the skimmer entrance. Future experiments are planned to field test the water jets in fixed and mobile applications on inland waterways.


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