scholarly journals Infectivity of Giardia duodenalis Cysts from UV Light-Disinfected Wastewater Effluent Using a Nude BALB/c Mouse Model

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Luciana Urbano dos Santos ◽  
Delma Pegolo Alves ◽  
Ana Maria Aparecida Guaraldo ◽  
Romeu Cantusio Neto ◽  
Mauricio Durigan ◽  
...  
Keyword(s):  
Uv Light ◽  
Sewage Treatment ◽  
Treatment Plant ◽  
Giardia Duodenalis ◽  
Average Concentration ◽  
Wastewater Effluent ◽  
Uv Disinfection ◽  
Disinfection Process ◽  
High Concentrations ◽  
The City

Giardia duodenalis is a protozoan of public health interest that causes gastroenteritis in humans and other animals. In the city of Campinas in southeast Brazil, giardiasis is endemic, and this pathogen is detected at high concentrations in wastewater effluents, which are potential reservoirs for transmission. The Samambaia wastewater treatment plant (WWTP) in the city of Campinas employs an activated sludge system for sewage treatment and ultraviolet (UV) light for disinfection of effluents. To evaluate this disinfection process with respect to inactivating G. duodenalis cysts, two sample types were investigated: (i) effluent without UV disinfection (EFL) and (ii) effluent with UV disinfection (EFL+UV). Nude immunodeficient BALB/c mice were intragastrically inoculated with a mean dose of 14 cysts of G. duodenalis recovered from effluent from this WWTP, EFL, or EFL+UV. All animals inoculated with G. duodenalis cysts developed the infection, but animals inoculated with UV-exposed cysts released a lower average concentration of cysts in their faeces than animals inoculated with cysts that were not UV disinfected. Trophozoites were also observed in both groups of animals. These findings suggest that G. duodenalis cysts exposed to UV light were damaged but were still able to cause infection.

Protesting the “Perfect City”

Memory Lands ◽  
2018 ◽  
Author(s):  
Christine M. DeLucia
Keyword(s):  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
King Philip's War ◽  
Urban Indians ◽  
Tribal Communities ◽  
Dugout Canoes ◽  
Social Opportunities ◽  
Indigenous Perspectives ◽  
The City

This chapter follows Native and Euro-American communities in eastern Massachusetts through the twentieth and twenty-first centuries, examining a series of commemorations and counterprotests that unfolded in urbanizing areas and related sites. It analyzes how Bostonians’ conceptions of the city and modernity tended to exclude Native peoples from both, instead relegating them to the past—despite the presence of numerous “Urban Indians” in the growing metropolis, who were seeking employment and social opportunities. It considers a series of pageants and historical markers erected across the Commonwealth, as well as Native pushback against dominant Euro-American narratives about history, such as a 1970 gathering in Patuxet/Plymouth, Massachusetts that foregrounded Indigenous perspectives and inaugurated an annual National Day of Mourning. The chapter also details how tribal communities challenged plans to build a sewage treatment plant on Deer Island, on grounds considered intensely sensitive for their ties to the incarcerations of King Philip’s War. Finally, it illuminates a recent series of memorial journeys along the Charles River and Boston Harbor Islands in which mishoonash (Native dugout canoes) have played important roles in reconnecting Native descendants to the landscapes of ancestors, as well as providing avenues for Indigenous solidarities into the future.

Modelling wastewater effluent mixing and dispersion in a tidal channel

2010 ◽  
Vol 37 (1) ◽  
pp. 99-111 ◽  
Author(s):  
S. S. Li ◽  
D. O. Hodgins
Keyword(s):  
Discharge Rate ◽  
Treatment Plant ◽  
Field Measurements ◽  
Numerical Approach ◽  
Wastewater Effluent ◽  
Initial Dilution ◽  
Discharge Flow Rate ◽  
High Concentrations ◽  
Ambient Currents ◽  
Water Quality Problem

The dilution and dispersion behaviour of wastewater effluent discharged from the Lions Gate Wastewater Treatment Plant into Burrard Inlet in British Columbia is investigated. This investigation focuses on the initial dilution zone, where low dilutions or high concentrations of contaminants contained in the effluent potentially pose a water-quality problem. We took the numerical approach and used field measurements of effluent dilutions, ambient stratification, and currents made in the vicinity of the discharge point for model input and verification. Predictions of effluent dilution and trapping compare well with the field results. We successfully determined the zone of exposure, effluent dilutions, trapping depths, and dispersion pathways as a function of discharge flow rate, ambient currents, and ambient stratification. It is shown that effluent trapping and dilutions in the initial dilution zone are governed mainly by the ambient currents, discharge rate, and, to a small extent, ambient stratification.

A Certain City Public Building Energy Consumption and Energy Saving of Economic Research and Statistics

2012 ◽  
Vol 512-515 ◽  
pp. 2842-2847
Author(s):  
Wei Yu ◽  
Wei Teng Li ◽  
Mei Juan Huo
Keyword(s):  
Economic Analysis ◽  
Statistical Power ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Economic Research ◽  
Pump System ◽  
Heat Pump System ◽  
Site Monitoring ◽  
The City

In this paper, the main public buildings, Lang fang City, Hebei province, the research summary and statistical power to the city building a sewage treatment plant sewage source heat pump system operating on-site monitoring, the monitoring results of economic analysis with traditional heating methods from the initial investment and operation of both comprehensive economic analysis and comparison.

scholarly journals Microbial air contamination on the premises of the sewage treatment plant in Bydgoszcz (Poland) and antibiotic resistance of Staphylococcus spp.

2017 ◽  
Vol 43 (4) ◽  
pp. 58-65 ◽  
Author(s):  
Marta Małecka-Adamowicz ◽  
Łukasz Kubera ◽  
Wojciech Donderski ◽  
Katarzyna Kolet
Keyword(s):  
Heterotrophic Bacteria ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Antibiotic Sensitivity ◽  
Primary Treatment ◽  
Average Concentration ◽  
Diffusion Method ◽  
Air Contamination ◽  
Staphylococcus Spp

AbstractThe study was aimed at evaluating microbial contamination on the premises of the sewage treatment plant by determining the concentrations of selected groups of airborne microorganisms. Another objective was to determine the antibiotic sensitivity patterns of isolated strains of staphylococci. The research was conducted in a seasonal cycle, by the impaction method using Merck MAS-100 air sampler. Samples were collected at six sites, each representing a different stage of sewage treatment. The susceptibility of isolated staphylococci was assessed with the disc-diffusion method, following the recommendations of the EUCAST. The results indicate that the microbial population in the air of the investigated area was dominated by mold fungi, whose highest average concentration was recorded at site IV located near the final clarifier (7672 CFU•m-3). Heterotrophic bacteria and mannitol-positive staphylococci were the most numerous at locations where sewage undergoes primary treatment. In each subseuqent stage the number of microorganisms emitted into the air from the sewage was lower. Antibiograms show that more than 50% of Staphylococcus spp. exhibited resistance to penicillin and 20% to rifampicin. In addition, 90% of the analyzed strains were sensitive to other antibiotics. The fungal community included the following genera: Cladosporium, Fusarium, Alternaria, Penicillium, Aspergillus, Aureobasidium, and Acremonium.The highest air contamination with all studied groups of microorganisms was recorded at the locations where mechanical sewage treatment was performed. During the subsequent stages lower numbers of heterotrophic bacteria were emitted into the air. The air in the investigated sewage treatment plant did not contain multidrug-resistant staphylococci.

Development of UV Distribution Model for the Non-Contact Type UV Disinfection System

2011 ◽  
Vol 9 (1) ◽  
Author(s):  
Sung Hong Kim ◽  
Young Gyun Choi ◽  
Dooil Kim
Keyword(s):  
Mathematical Model ◽  
Exposure Time ◽  
Uv Light ◽  
Treatment Plant ◽  
Water Layer ◽  
Distribution Model ◽  
Uv Disinfection ◽  
Contact Type ◽  
Irradiation System ◽  
Uv Lamp

Fouling on the quartz sleeve reduces the transmittance of UV light through the sleeve into the water in submerged UV disinfection system. The concept of a non-contact type of UV disinfection system was introduced in this study. UV lamps and their quartz sleeves hang over the water surface and there is no interface between the sleeve and water. Indeed, there is no fouling. Based on optical laws and UV distribution model, a detailed mathematical model for a non-contact type UV disinfection system was developed and simulated in this study. UV light passes through 4 media of air-quartz-air and water in case of non-contact type irradiation system. By the simulation of the mathematical model of the system, it is known that the non-contact type of UV system requires 2.5 times more powerful UV lamp or a lamp with longer exposure time than that of the submerged type of UV system. In a non-contact type of UV system, high-reflective ceiling material can increase the UV intensity of the water layer as much as 28 percent more than the case of non-reflective ceiling material. The non-contact type UV irradiation system requires more powerful lamp or one that have longer exposure time. Nevertheless, considering the fouling attenuation and maintenance problem associated with the fouling, non-contact type of UV disinfection system deserves to be practically considered, especially in a small to middle scale water or wastewater treatment plant.

Sewage Wastewater Treatment Plant Inverted AAO Process Design

2014 ◽  
Vol 1079-1080 ◽  
pp. 480-483
Author(s):  
Li Wang
Keyword(s):  
Wastewater Treatment ◽  
Process Design ◽  
Wastewater Treatment Plant ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Structure Design ◽  
Main Task ◽  
The City

The graduation design topic for a sewage treatment plant processesdesign - inverted AAO process in durian. Main task is tantamount to designaccording to the requirement of the nature of the city sewage, sewage, scalepreliminary design to complete sewage treatment plant and single processing structure design.

Experimental Studies of CS Type UV Sterilizer for the Urban Sewage Treatment

2013 ◽  
Vol 361-363 ◽  
pp. 601-605
Author(s):  
Ji Ku Zhang ◽  
Yang Yang Li ◽  
Chen Zhang ◽  
Yan Bin Yang
Keyword(s):  
Removal Rate ◽  
Sewage Treatment ◽  
Experimental Studies ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Uv Disinfection ◽  
Secondary Effluent ◽  
Urban Sewage ◽  
High Doses ◽  
Uv Dose

By treating the secondary effluent of Sanbaotun sewage treatment plant in Fushun with the CS type UV Sterilizer, the experiment researches the influence on the removal rate which includes the factors of turbidity, chromaticity, initial E.coli concentration of raw water, UV dose. The results show that the turbidity does not influence on UV disinfection efficiency with the turbidity from 1.5NTU to 3.8NTU. In the low-dose UV disinfection process, the influent sewage turbidity should under 4NTU to ensure the disinfection efficiency. Low chromaticity does not affect the UV disinfection efficiency, with the influent sewage chromaticity is under 15 degrees.The initial E. coli has a certain impact on little doses of UV disinfection with the concentration from 175 × 104 A/ L to 230 × 104 A/ L, no impact on high doses of UV disinfection。

Disinfection, Recontamination and Regrowth of Indicator Bacteria in a Wastewater Sludge Heat Treatment System

1988 ◽  
Vol 20 (11-12) ◽  
pp. 329-335
Author(s):  
Roger S. Fujioka ◽  
Wesley M. Hirano ◽  
Philip C. Loh
Keyword(s):  
Heat Treatment ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Wastewater Sludge ◽  
Indicator Bacteria ◽  
Primary Sludge ◽  
Heat Treated ◽  
Sludge Cake ◽  
High Concentrations

The largest sewage treatment plant in Hawaii produces 25,400 kg/day of primary sludge that is heat-treated (190°C) under 330 psig for 3 0 min. Although this treatment should result in a sterilized sludge product, the final sludge cake often contains high concentrations of fecal-borne indicator bacteria. The heat-treatment process was shown to disinfect the sludge of indicator bacteria. However, post contamination of the heat-treated sludge by raw sludge and by chlorinated primary effluent and the regrowth of indicator bacteria in the sludge storage tanks resulted in the presence of indicator bacteria in the sludge cake.

Possibilities for increased nutrient removal with a final filtration stage

1996 ◽  
Vol 33 (12) ◽  
pp. 147-153
Author(s):  
M. Rothman ◽  
J. Hultgren
Keyword(s):  
Activated Sludge ◽  
Nitrogen Removal ◽  
Nutrient Removal ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
High Concentrations ◽  
Winter Time ◽  
Filtration Stage

Bromma sewage treatment plant (STP) is one of three plants in Stockholm. To meet more stringent requirements for nutrient removal the plant has been extended with a final filtration stage. Earlier it has not been possible to operate the plant with nitrification during winter time. Bad settling properties of the activated sludge have led to bulking sludge and high concentrations of BOD and phosphorus in the effluent. With the filter stage it is now possible to reduce the load on the biological stage by by-passing part of the flow directly to the filters. The result has been very promising and it seems that the plant can meet the new demands for nitrogen removal without extension of the aerated volumes.

scholarly journals Existence, Fate And Risk Assessment of Pharmaceuticals During Treatment of Domestic Wastewater: Mass Flow And Consumption Calculation

2021 ◽  
Author(s):  
Mohamed I. Badawy ◽  
Fatma A. El-Gohary ◽  
Mahmoud S. Abdel-Wahed ◽  
Tarek A. Gad-Allah ◽  
Mohamed Eid Ali
Keyword(s):  
Risk Assessment ◽  
High Performance ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Domestic Wastewater ◽  
Average Concentration ◽  
Mass Load ◽  
The Individual ◽  
Final Effluent

Abstract In Egypt, pharmaceuticals consumption is dramatically increasing, owing to the population growth and the unrestricted sale manner. Therefore, the occurrence and fate of nine pharmaceutical compounds (PhCs) were scrutinized at the different stages of sewage treatment plant (STP) in Giza, Egypt. Levels of these PhCs were assessed in wastewater and sludge phases by a high-performance liquid chromatography coupled. Nine PhCs were detected in both wastewater and sludge. Average concentration of the total PhCs detected in influent, primary sedimentation effluent and final effluent were 227, 155 and 89 µg/L, respectively. The overall removal efficiency of the individual PhCs ranged from 18 % to 72 % removal. The occurrence trend revealed that biodegradation and sorption are the concurrently removal mechanisms of the studied PhCs. As well, the calculated total mass load of individual PhCs were in the range 328 – 42256, 152 – 26180, and 257 – 6625 g d-1 for influent, effluent and sludge. Meanwhile, the calculated range of personal mass load of the individual PhCs was 193 – 15274, 120 – 10864 and 34 - 265 µg d-1 Pe-1, for the influent, the final effluent and the sludge, respectively. The overall personal pharmaceutical consumption per day in West of Greater Cairo was estimated based on influent concentration of STP. Sulfamethoxazole, paracetamol and diclofenac were identified with the highest levels in the influent of STP, PSE and FE as well as in the dewatered sludge. Furthermore, the high concentrations of these compounds in the sludge confirms the sorption pathway removal of PhCs. Generally, the average daily and annual consumption per capita of the most dominant PhCs in wastewater; sulfamethazole, paracetamol and diclofenac are 60.09, 34.79, and 26.69 mg d-1 Pe-1 and 22, 12.52, and 12.52 g y-1 Pe-1, respectively. Moreover, risk assessment (RQ) for the detected PhCs in FE is greatly higher than the predicted non-effect concentration (PNEC). Conclusively, the FE of STP is considered a risky source for PhCs in adjacent surface water.

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