Viruses in sewage: effect of phosphate removal with calcium hydroxide (lime)

1978 ◽  
Vol 24 (8) ◽  
pp. 1004-1006 ◽  
Author(s):  
Syed A. Sattar ◽  
Sami Ramia

During calcium hydroxide (lime) treatment (pH 9.5 to 10.5) of wastewaters for phosphate removal there was also a two-log removal of added poliovirus (type I, Sabin) from effluents. A similar virus reduction was seen in the sludge generated in these experiments. However, in view of the limitations of techniques for virus recovery from sludge, only a small portion of the infectious virus present in lime sludge may have been detected. Storage of lime sludge at 28 °C for up to 48 h produced no appreciable reduction in the virus titre.Five sets of field samples of sewage, effluents, and sludge from a sewage treatment plant (Kemptville, Ont.) which utilizes lime for phosphate removal were also examined for indigenous viruses using BS-C-1 cells. All of the samples of lime sludge and 80% of the samples of both sewage and lime-treated effluent revealed virus; after chlorination only 20% of the lime-treated effluent samples were positive for virus. In contrast, in an earlier study with essentially the same experimental set up, 76% of the sample of chlorinated primary effluent were found to contain virus. Because of the easily detectable quantities of infectious virus in lime sludge and due to the lack of virus inactivation during storage of such sludge, caution must be exercised in its handling and disposal.

1992 ◽  
Vol 25 (10) ◽  
pp. 55-67 ◽  
Author(s):  
R. C. Squires

The performance of Exxflow, a patented form of crossflow microfiltration, treating industrial wastewaters containing mixed heavy metals discharged by two types of industry is quantified and compared with the traditional technologies used for such treatment. Pilot trial results using Exxflow are shown and compared to the performance of the full scale plants now operating on these effluents. The operating costs of the Exxflow process are estimated for the two plants. One of which has been operating for 18 months and the other about 4 months. The Exxflow process is described and improvements which are being developed to lower the operating costs are presented. It is shown that industrial effluents containing mixed heavy metals are very effectively treated by the Exxflow process and since the installation of the plants the treated effluent has been of a quality suitable for discharge to the River Thames in one case and to a sewage treatment plant in the other. Unlike other processes, Exxflow has shown that it can successfully treat effluent containing mixed metals and that removal of antimony from mixed metal waste waters is affected by the concentration of sodium sulphate in the wastewater.


2021 ◽  
Author(s):  
Yanyan Fang

Abstract Microplastics (MPs) have been found in all environment matrices and have become an issue of concern worldwide. In this study, Baiyangdian Lake in Northern China was investigated for the presence of MPs (0.45 µm–5 mm) in sediment and at different water depths. MPs were found at 1,000–20,000 pieces/m3 (average 9,595) in water and at 400–2,200 pieces/kg (average 1,023) in sediment. Since the implementation of pollution abatement measures, visible MPs have been nearly eliminated; the MPs found in this study were mainly in the micrometer range, with no more than 3–5 pieces greater than 1 mm per sample. The main forms of MPs were fibrous and fragmented, and the main components were polyamide, polyethylene, and polypropylene. MPs found in water near a garbage transfer station showed the following abundance of MPs: surface water < middle water < bottom water. The sediment contained a higher amount of MP fragments, indicating that the historical transfer and disposal of garbage was a main source of plastic deposition in this area. There was a high content of fibrous MPs in surface water, while the abundance of fragmented MPs increased with the depth of water. The main sources of MPs in the study area were residential activities, local plastic factories, and the treated effluent from a sewage treatment plant.


2019 ◽  
Vol 15 (1) ◽  
pp. 40-44 ◽  
Author(s):  
Bikram Gautam ◽  
Anjita Rajbhanshi ◽  
Rameshwar Adhikari

Background: Water sources such as lakes, ponds, river etc. have been continuously contaminated by the   micro organisms and chemicals. The former can pose a significant threat to human health. This work aims at detecting the bacterial load before and after the sewage treatment and hence isolating pathogens from the sewage before primary treatment and secondary treated effluent. Methods: Grab sampling (50mL sewage before primary treatment and secondary treated effluent) was performed for 20 days in the Guheswori  sewage treatment plant. The reduction in microbial load was determined through heterotrophic plate count. Pathogens were screened from the effluent obtained from the secondary treatment plant. Results: Bacterial load reduction was found to be about 48.02% on average. The observed bacterial load reduction might have been caused by bacteriophage flocculation and sedimentation. Pathogens isolated from the treated effluent were Escherichia coli, Salmonella Typhi, Enterococcus faecalis, Staphylococcus aureus, Coagulase negative Staphylococcus (CONS), Citrobacter fruendii, Enterobacter aerogenes, Proteus mirabilis, P. vulgaris, Pseudomonas  aeruginosa. Conclusions: It has been found that the sewage treatment plant helps to reduce the bacterial load which is, however, not capable of effluent polishing where all pathogens are killed. 


Irriga ◽  
2021 ◽  
Vol 1 (4) ◽  
pp. 671-677
Author(s):  
LIBIANE MARINHO BERNARDINO ◽  
PATRÍCIA DA SILVA COSTA ◽  
VERA LÚCIA ANTUNES DE LIMA ◽  
RENER LUCIANO DE SOUZA FERRAZ

POTENCIAL DE REÚSO DE EFLUENTES TRATADOS PARA IRRIGAÇÃO PERIURBANA NO MUNICÍPIO DE GUARABIRA/PB     LIBIANE MARINHO BERNARDINO1; PATRÍCIA DA SILVA COSTA2; VERA LÚCIA ANTUNES DE LIMA3 E RENER LUCIANO DE SOUZA FERRAZ4.   1 Mestranda em Gestão e Regulação em Recursos Hídricos, Unidade Acadêmica de Tecnologia do Desenvolvimento, UFCG, Rua Luiz Grande, s/n, Frei Damião, CEP 58540-000, Sumé, PB, Brasil, [email protected] 2 Doutoranda em Engenharia Agrícola, Unidade Acadêmica de Engenharia Agrícola, UFCG, Rua Aprigio Veloso, 882, Universitário, CEP 58429-900, Campina Grande, PB, Brasil, [email protected] 3 Profa. Doutora em Engenharia Agrícola, Unidade Acadêmica de Engenharia Agrícola, UFCG, Rua Aprigio Veloso, 882, Universitário, CEP 58429-900, Campina Grande, PB, Brasil, [email protected] 4 Prof. Doutor em Engenharia Agrícola, Unidade Acadêmica de Desenvolvimento Sustentável do Semiárido, UFCG, Rua Luiz Grande, s/n, Frei Damião, CEP 58540-000, Sumé, PB, Brasil, [email protected]     1 RESUMO   A água é um recurso finito que se encontra escasso, o que justifica a busca por gestão e inovação de práticas que a preserve. O objetivo da pesquisa é avaliar o potencial de reúso dos efluentes tratados para irrigação periurbana. Foram levantados dados de uma Estação de Tratamento de Esgotos (ETE), localizada no município de Guarabira, PB, e operada pela Companhia de Água e Esgotos do Estado da Paraíba (CAGEPA), durante o período de janeiro a dezembro de 2019. Analisou-se os seguintes parâmetros físico-químicos e bacteriológicos: Potencial Hidrogeniônico (pH), Condutividade Elétrica (CE), Demanda Bioquímica de Oxigênio (DBO), Demanda Química de Oxigênio (DQO), Sólidos Totais (ST), Oxigênio Dissolvido (OD), Fósforo Total, e Coliformes Termotolerantes. Os dados foram submetidos à análise descritiva e expresso em valores mínimos, máximos e médios. Os indicadores foram satisfatórios para irrigação restrita, porém com a necessidade de tratamento complementar para determinados cultivos. O potencial de reúso   dos efluentes tratados na ETE pode beneficiar uma área de 118,7 ha considerando uma demanda de irrigação de 18.000 m³ ha-1 ano-1, o que demonstra ser um recurso sustentável e que precisa ser regulamentado no Brasil.   Palavras-chave: recursos hídricos, resíduos líquidos, tratamento de água, fertirrigação.     BERNARDINO, L. M.; COSTA, P. S.; LIMA, V. L. A.; FERRAZ, L. R. S. REUSE POTENTIAL OF TREATED EFFLUENTS FOR PERIURBAN IRRIGATION IN THE MUNICIPALITY OF GUARABIRA/PB     2 ABSTRACT   Water is at the center of sustainable development and a finite resource that is in short supply, which justifies the search for management and innovation of practices that preserve it. This research aims to evaluate the potential for reuse of treated effluent for periurban irrigation. Data were collected from a Sewage Treatment Plant (STP), located in the municipality of Guarabira, PB, and operated by the Water and Sewage Company of the State of Paraíba (CAGEPA), during the period from January to December 2019, with the analysis of the following physicochemical and bacteriological parameters: Hipogenic Potential (pH), Electrical Conductivity (CE), Biochemical Oxygen Demand (DBO), Chemical Oxygen Demand (DQO), Total Solids (ST), Dissolved Oxygen (OD), Total Phosphorus, and Thermotolerant Coliforms. The data were submitted to the descriptive analysis and expressed as minimum, maximum and average values. The indicators were satisfactory for restricted irrigation, but with the need for complementary treatment for certain crops. The potential for reuse of the effluents treated in the ETE can benefit an area of 118.7 ha considering an irrigation demand of 18,000 m³ ha-1 year-1, which demonstrates to be a sustainable resource that needs to be regulated in Brazil.   Keywords: Water resources, liquid waste, water treatment, fertigation.


1973 ◽  
Vol 8 (1) ◽  
pp. 122-147
Author(s):  
J. D. O’Blenis ◽  
T.R. Warriner

Abstract The current widespread practice of disposal of water filtration plant wastes by direct discharge to receiving waters is coming under critical review by regulatory agencies. Among the alternatives for management of these wastes is the possibility of disposal to sanitary sewer systems. Since a recent nation-wide survey had established alum sludge as the most common waste generated by filtration plants, research was initiated to study the effects of water plant alum sludge on primary sewage treatment. A pilot primary sewage treatment plant was constructed and operated with a raw sewage feed of five litres per minute. A laboratory jar test program was conducted to supplement pilot plant operation. Sludges from two different water purification plants were tested along with alum and combinations of alum and water purification plant sludge for their effects on the removal of suspended solids, chemical oxygen demand (COD) and phosphates. The data showed jar testing to be a good indicator of pilot plant performance. Suspended solids, COD and phosphate removal efficiencies were improved by the addition of the sludges. The phosphate removal capacity of water treatment plant alum sludge was approximately the same as that reported for aluminum hydroxide, or about 1/7 to 1/9 of that determined for alum (as Aluminum). Recycling of the sludges improved phosphate removal performance.


2020 ◽  
Vol 5 (2) ◽  
pp. 53-57
Author(s):  
Nandini Moondra ◽  
Namrata D Jariwala ◽  
Robin A Christian

Conventional domestic wastewater treatment in most developing countries is confined to secondary treatments, mainly focusing on solids and organics removal, which results in eutrophication when the effluents are discharged into receiving bodies. Thus, to resolve the issues associated with the conventional treatment system, in the present study, microalgae was introduced in the primary treated effluent collected from a sewage treatment plant to study the efficiency of the system in reducing eutrophication and other challenges of secondary treatment. Phycoremediation is an effective and eco-friendly treatment alternative that reduced the primary-treated effluent’s PO4-P, NH3-N and COD concentration to 97.89%, 98.81%, and 88.24%, respectively at the identical HRT practiced for secondary treatment. One-way ANOVA was also conducted to determine the effectiveness of the system statistically. The experimental and statistical analysis proved that microalgal treatment could resolve the challenges of conventional secondary treatments if adopted for domestic wastewater.


Author(s):  
Vinay Khewale

A sewage water treatment plant is necessary to receive and treat waste water (Domestic, Commercial, and Industrial). Its objective is to be convert harmful waste water to safe water environmentally and treated effluent and treated sludge suitable for reuse and disposal such as farm fertilizer. The characteristics of waste water have been performed followed by design of sewage treatment plant. The present study includes design of sewage treatment plant and analysis of waste water – PH value, Total Dissolved Solids (TDS), Total Suspended Solids (TSS), Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Solids (TS), Hardness, Chloride, Acidity, Oil, Fats and grease etc. The sample collection of waste water has been done in many times in a day to obtain an average value of major parameter. Followed by values of this parameter, calculations are done for designing the units of sewage treatment plant and layout is prepared for the same


2008 ◽  
Vol 6 (3) ◽  
pp. 351-358 ◽  
Author(s):  
A. Arraj ◽  
J. Bohatier ◽  
C. Aumeran ◽  
J. L. Bailly ◽  
H. Laveran ◽  
...  

The aim of this study was to assess the presence and seasonal frequency of various enteric viruses in wastewater treatment. The detection of astrovirus, norovirus, enterovirus, hepatitis A virus (HAV) and rotavirus was carried out by molecular analyses in concentrated water samples collected over 18 months at the entrance and exit of an activated sludge sewage treatment plant. The reverse transcriptase-polymerase chain reaction (RT-PCR) results were confirmed by sequencing, and comparative phylogenetic analysis was performed on the isolated strains. Genomes of human astrovirus and human rotavirus were identified in 26/29 and 11/29 samples of raw sewage, respectively, and in 12/29 and 13/29 treated effluent samples, respectively. Some rotavirus sequences detected in environmental samples were very close to those of clinical strains. Noroviruses, enteroviruses and HAV were not detected during the study period. This could be related to the small sample volume, to the sensitivity of the detection methods or to local epidemiological situations. Frequent detection of viral RNA, whether infectious or not, in the exit effluent of sewage treatment indicates wide dispersion of enteric viruses in the environment. Consequently, viral contamination resulting from the use of these treated waters is a risk that needs to be addressed.


2008 ◽  
Vol 52 (7) ◽  
pp. 2581-2592 ◽  
Author(s):  
Bruno Périchon ◽  
Pierre Bogaerts ◽  
Thierry Lambert ◽  
Lionel Frangeul ◽  
Patrice Courvalin ◽  
...  

ABSTRACT Self-transferable IncFI plasmid pIP1206, isolated from an Escherichia coli clinical isolate, carries two new resistance determinants: qepA, which confers resistance to hydrophylic fluoroquinolones by efflux, and rmtB, which specifies a 16S rRNA methylase conferring high-level aminoglycoside resistance. Analysis of the 168,113-bp sequence (51% G+C) revealed that pIP1206 was composed of several subregions separated by copies of insertion sequences. Of 151 open reading frames, 56 (37%) were also present in pRSB107, isolated from a bacterium in a sewage treatment plant. pIP1206 contained four replication regions (RepFIA, RepFIB, and two partial RepFII regions) and a transfer region 91% identical with that of pAPEC-O1-ColBM, a plasmid isolated from an avian pathogenic E. coli. A putative oriT region was found upstream from the transfer region. The antibiotic resistance genes tet(A), catA1, bla TEM-1, rmtB, and qepA were clustered in a 33.5-kb fragment delineated by two IS26 elements that also carried a class 1 integron, including the sulI, qacEΔ1, aad4, and dfrA17 genes and Tn10, Tn21, and Tn3-like transposons. The plasmid also possessed a raffinose operon, an arginine deiminase pathway, a putative iron acquisition gene cluster, an S-methylmethionine metabolism operon, two virulence-associated genes, and a type I DNA restriction-modification (R-M) system. Three toxin/antitoxin systems and the R-M system ensured stabilization of the plasmid in the host bacteria. These data suggest that the mosaic structure of pIP1206 could have resulted from recombination between pRSB107 and a pAPEC-O1-ColBM-like plasmid, combined with structural rearrangements associated with acquisition of additional DNA by recombination and of mobile genetic elements by transposition.


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