Evaluation of activated sludge treatment and the efficiency of the disinfection of Giardia species cysts and Cryptosporidium oocysts by UV at a sludge treatment plant in Campinas, south-east Brazil

2006 ◽  
Vol 54 (3) ◽  
pp. 89-94 ◽  
Author(s):  
R. Cantusio Neto ◽  
J.U. Santos ◽  
R.M.B. Franco
Keyword(s):  
Activated Sludge ◽  
Treatment Plant ◽  
Uv Disinfection ◽  
Waterborne Diseases ◽  
Activated Sludge Process ◽  
Sludge Treatment ◽  
Treated Effluent ◽  
Two Samples ◽  
Cryptosporidium Oocysts ◽  
Giardia Cysts

Among many waterborne diseases the giardiasis and cryptosporidiosis are of particular public health interest, because Giardia cysts and Cryptosporidium oocysts can persist for long periods in the environment, and both pathogenic protozoa have been implicated as the cause of many outbreaks of gastroenteritis in the last 25 years. In order to evaluate the efficiency of cysts and oocysts' removal by the activated sludge process, and by UV reactor in inactivating cysts and oocysts in one wastewater treatment plant (WWTP) of Campinas, three sampling points were selected for study: (1) influent, (2) treated effluent without UV disinfection and (3) treated effluent with UV disinfection. Giardia spp. cysts prevailed with higher density in the three different sample types. Cryptosporidium spp. oocysts were observed in only two samples of influent and just one sample of treated sewage with UV disinfection. In the animal infectivity assay for Giardia spp, one mouse of the UV treated group revealed trophozoites in intestinal scrapings. The results of the present study indicate that treatment by activated sludge process delivered a reduction of 98.9% of cysts and 99.7% of oocysts and UV disinfection was not completely efficient regarding the inactivation of Giardia cysts in the case of the WWTP studied.

scholarly journals Occurrence of Giardia cysts and Cryptosporidium oocysts in activated sludge samples in Campinas, SP, Brazil

2004 ◽  
Vol 46 (6) ◽  
pp. 309-313 ◽  
Author(s):  
Luciana Urbano Santos ◽  
Taís Rondello Bonatti ◽  
Romeu Cantusio Neto ◽  
Regina Maura Bueno Franco
Keyword(s):  
Activated Sludge ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
High Concentration ◽  
Potential Source ◽  
Two Samples ◽  
Cryptosporidium Oocysts ◽  
Flotation Method ◽  
Giardia Cysts

Giardia and Cryptosporidium have caused several outbreaks of gastroenteritis in humans associated with drinking water. Contaminated sewage effluents are recognized as a potential source of waterborne protozoa. Due to the lack of studies about the occurrence of these parasites in sewage samples in Brazil, we compared the efficiency of two procedures for concentrating cysts and oocysts in activated sludge samples of one sewage treatment plant. For this, the samples were submitted to i) concentration by the ether clarification procedure (ECP) and to ii) purification by sucrose flotation method (SFM) and aliquots of the pellets were examined by immunofluorescence. Giardia cysts were present in all samples (100.0%; n = 8) when using ECP and kit 1 reagents, while kit 2 resulted in six positive samples (85.7%; n = 7). As for SFM, cysts were detected in 75.0% and 100.0% of these samples (for kit 1 and 2, respectively). Regarding Cryptosporidium, two samples (25.0%; kit 1 and 28.5% for kit 2) were detected positive by using ECP, while for SFM, only one sample (examined by kit 1) was positive (12.5%). The results of the control trial revealed Giardia and Cryptosporidium recovery efficiency rates for ECP of 54.5% and 9.6%, while SFM was 10.5% and 3.2%, respectively. Considering the high concentration detected, a previous evaluation of the activated sludge before its application in agriculture is recommended and with some improvement, ECP would be an appropriate simple technique for protozoa detection in sewage samples.

Deemulsification of Water-in-Oil Emulsion with Sludges

1987 ◽  
Vol 22 (3) ◽  
pp. 437-443 ◽  
Author(s):  
N. Kosaric ◽  
Z. Duvnjak
Keyword(s):  
Activated Sludge ◽  
Room Temperature ◽  
Petroleum Refinery ◽  
Treatment Plant ◽  
Granular Sludge ◽  
Activated Sludge Process ◽  
Sludge Treatment ◽  
Oil Emulsion ◽  
Water In Oil Emulsion ◽  
Aerobic Sludge

Abstract Aerobic sludge from a municipal activated sludge treatment plant, sludge from a conventional municipal anaerobic digester, aerobic sludge from an activated sludge process of a petroleum refinery, and granular sludge from an upflow sludge blanket reactor (USBR) were tested in the deemulsification of a water-in-oil emulsion. All sludges except the last one, showed a good deemulsification capability and could he used for a partial deemulsification of such emulsions. The rate and degree of the deemulsifications increased with an increase in sludge concentrations. The deemulsifications were faster at 85°C and required smaller amounts of sludge than in the case of the deemulsifications at room temperature. An extended stirring (up to a certain limit) in the course of the dispersion of sludge emulsion helped the deemulsification. Too vigorous agitation had an adverse effect. The deemulsification effect of sludge became less visible with an increase in the dilution of emulsion which caused an increase in its spontaneous deemulsification.

Sensitivity of Effluent Variables in Activated Sludge Process

2017 ◽  
Vol 13 (2) ◽  
Author(s):  
B Vivekanandan ◽  
K Jeyannathann ◽  
A. Seshagiri Rao
Keyword(s):  
Activated Sludge ◽  
Flow Rate ◽  
Oxygen Transfer Rate ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Maximum Flow ◽  
Activated Sludge Process ◽  
Flow Conditions ◽  
Treated Effluent ◽  
Influent Flow

Abstract The quality of a treated effluent changes when there is a sudden variation in the influent flow to the wastewater treatment plant during dry, rain, and storm weather conditions. In this study, various influent flow conditions in an activated sludge process are considered that affect the sensitivity of effluent variables such as chemical oxygen demand (COD), biological oxygen demand (BOD), nitrate nitrogen (SNO), ammonical nitrogen (SNH), and total nitrogen (TN) with respect to varying internal recycle flow rate (Qa), sludge recycle flow rate (Qr), sludge wastage flow rate (Qw) and oxygen transfer rate co-efficient of aerobic tanks (KLa(3,4,5)). The analysis has been carried out based on benchmark simulation model no.1 (BSM 1) plant layout which comprises of two models namely activated sludge model no.1 (ASM 1) and simple one dimensional (Simple 1-D) Takacs model. Based on the present analysis, it is observed that the changes in influent flow rate have larger impact on the effluent variables. This variation can be subdued by introducing additional tanks to smoothen the perturbations or using internal recycle rate from the fifth tank in order to maintain the flow around the optimal influent flow rate. The sludge wastage rate has a greater impact on all effluent variables except nitrogenous variables during maximum flow conditions.

Carbon Dioxide in Pulp and Paper Mill Effluents from Oxygen-Activated Sludge Treatment Plants as a Potential Source of Distress and Toxicity to Fish

2000 ◽  
Vol 35 (2) ◽  
pp. 189-200 ◽  
Author(s):  
Brian O’Connor ◽  
Tibor Kovacs ◽  
Sharon Gibbons ◽  
Al Strang
Keyword(s):  
Carbon Dioxide ◽  
Rainbow Trout ◽  
Activated Sludge ◽  
Treatment Plant ◽  
Carbon Dioxide Concentration ◽  
Regulatory Compliance ◽  
Sludge Treatment ◽  
Ph Adjustment ◽  
Paper Mill Effluents ◽  
Treated Effluent

Abstract Rainbow trout exposed to effluent from a UNOX (oxygen activated sludge) treatment plant were found to exhibit signs of distress during the first hours of exposure. While the final effluent was not acutely lethal at full strength, it was still important to determine the cause of the distress to ensure that the mill's effluents remain in regulatory compliance. The use of a series of effluent manipulations involving pH adjustment and aeration as well as observations of symptoms exhibited by the fish were successful in identifying carbon dioxide as the cause of fish distress for the UNOX-treated effluent. For rainbow trout, the symptoms of exposure to elevated levels of carbon dioxide of 100 mg/L or greater included loss of equilibrium, erratic swimming, gasping at the surface, sinking to the bottom of the test container and paralysis. The fish were found to eventually recover as the carbon dioxide was stripped from the effluent due to aeration during the test. A carbon dioxide concentration of 250 mg/L, however, was found to be lethal to trout A survey of mills using oxygen activated sludge treatment systems indicated that the carbon dioxide levels in effluents from such operations can range from 48 to 251 mg/L. Solutions for eliminating the fish distress and possible mortality associated with such effluents would be to lower the carbon dioxide level to below 100 mg/L by aeration or pH adjustment.

A Study on Application of the Technology for Activated Sludge Reducing

2017 ◽  
Vol 1 ◽  
pp. 1
Author(s):  
Zhan Yang
Keyword(s):  
Activated Sludge ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Activated Sludge Process ◽  
Sludge Treatment ◽  
Microbial Decomposition ◽  
Physical Chemical

Activated sludge process is the most widely used technology in sewage bioremediation up to now. However, there is also a serious problem with this technology, that is, a great amount of sludge will be left over. In view of this situation, a study has been carried out through the domestic activated technology for sludge treatment and also research on the effective sludge treatment. They made use of the microbial decomposition to decompose the oxide by using the means of physical, chemical, biological, etc. to minimize the effluent from the sewage treatment plant and thus, reduced the amount of sludge produced.

scholarly journals Comparison of two methodologies for detection of Giardia spp. cysts and Cryptosporidium spp. oocysts in activated sludge samples from a sewage treatment plant in the city of Campinas, São Paulo State, Brazil

2007 ◽  
Vol 5 (4) ◽  
pp. 609-614 ◽  
Author(s):  
Taís Rondello Bonatti ◽  
Regina Maura Bueno Franco ◽  
Romeu Cantusio Neto
Keyword(s):  
Activated Sludge ◽  
Gastrointestinal Disease ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Cryptosporidium Spp ◽  
Two Samples ◽  
Cryptosporidium Oocysts ◽  
Increasing Trend ◽  
The City

Giardia spp. and Cryptosporidium spp. are recognized worldwide as highly infectious protozoan parasites that can cause severe gastrointestinal disease in humans and animals. The detection of these pathogens in activated sludge samples becomes interesting since there is an increasing trend for the use of sewage sludge (biosolids) in agriculture. A total of 22 samples were collected and evaluated by means of Centrifugal – Concentration, followed or not followed by a purification process (ether clarification and sucrose flotation). Student t tests for comparison of the two procedures indicated a higher recovery rate of Giardia cysts with Centrifugal – Concentration; with regard to Cryptosporidium oocysts, no significant differences were found between the two methods, as only two samples were positive. The Centrifugal – Concentration procedure was shown to be the simplest and cheapest to perform, as emphasized by the efficiency recovery results.

A Study on Application of the Technology for Activated Sludge Reducing

2017 ◽  
Vol 1 (1) ◽  
pp. 1
Author(s):  
Zhan Yang
Keyword(s):  
Activated Sludge ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Activated Sludge Process ◽  
Sludge Treatment ◽  
Microbial Decomposition ◽  
Physical Chemical

Activated sludge process is the most widely used technology in sewage bioremediation up to now. However, there is also a serious problem with this technology, that is, a great amount of sludge will be left over. In view of this situation, a study has been carried out through the domestic activated technology for sludge treatment and also research on the effective sludge treatment. They made use of the microbial decomposition to decompose the oxide by using the means of physical, chemical, biological, etc. to minimize the effluent from the sewage treatment plant and thus, reduced the amount of sludge produced.

DESIGN PLANNING WASTEWATER TREATMENT PLANT OF NATA DE COCO INDUSTRY WITH THE ACTIVATED SLUDGE PROCESS

2016 ◽  
Vol 9 (2) ◽  
Author(s):  
Dinda Rita K. Hartaja ◽  
Imam Setiadi
Keyword(s):  
Waste Water ◽  
Wastewater Treatment ◽  
Activated Sludge ◽  
Waste Water Treatment ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Appropriate Technology ◽  
Waste Water Treatment Plant ◽  
Activated Sludge Process ◽  
High Level

Generally, wastewater of nata de coco industry contains suspended solids and COD were high, ranging from 90,000 mg / l. The high level of of the wastewater pollutants, resulting in nata de coco industry can not be directly disposed of its wastewater into the environment agency. Appropriate technology required in order to process the waste water so that the treated water can meet the environmental quality standards that are allowed. Designing the waste water treatment plant that is suitable and efficient for treating industrial wastewater nata de coco is the activated sludge process. Wastewater treatment using activated sludge process of conventional (standard) generally consists of initial sedimentation, aeration and final sedimentation.Keywords : Activated Sludge, Design, IPAL

Process evaluation of HASP with IMET system through SNR and SDNR for the efficient management of Sewage Treatment Plant

2008 ◽  
Vol 3 (1) ◽  
Author(s):  
Young H. Yoon ◽  
Jae R. Park ◽  
Sang W. Ahn ◽  
Kwang B. Ko ◽  
Kyung J. Min ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Linear Regression Analysis ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Reaction Rates ◽  
Nitrification Rate ◽  
Activated Sludge Process ◽  
Type Experiment ◽  
Batch Type ◽  
Nitrification And Denitrification

Hybrid Activated Sludge Process (HASP) with IMET was developed and applied to an activated sludge process for the advanced nutrient treatment in Korea. The characteristics of nitrogen removal from the HASP were investigated through a kinetic study by batch-type experiment. Online DB analysis produced from the IMET was conducted for the nutrient removal performance in the field demonstration plant treating 10,000 m3/day in G city of Korea. In this paper, we aimed to determine the effect of increasing NHM4+-N load on the specific nitrification rate (SNR) and the specific denitrification rate (SDNR) through a batch-type experiment, and to estimate the net reaction time for the phase-transfer rate using online DB analysis in the HASP operation. Experimental results include: (1) both the nitrification and denitrification followed first-order kinetics; (2) the maximum SNR and SDNR were 4.0301 mgN/gVSS·hr and 2.785 mgN/gVSS·hr, respectively; (3) comparison of reaction rates between nitrification and denitrification from the non-linear regression analysis found that nitrification rate was higher than denitrification.

Behaviour of Mechanically Blended Return-Sludge in Absence of Substrate

1970 ◽  
Vol 5 (1) ◽  
pp. 34-54
Author(s):  
Shyam D. Bokil ◽  
Jatinder K. Bewtra
Keyword(s):  
Activated Sludge ◽  
Suspended Solids ◽  
Treatment Plant ◽  
Aeration Rate ◽  
Batch Experiments ◽  
Sludge Treatment ◽  
Waring Blender ◽  
Settling Characteristics

Abstract Nine sets of batch experiments, each of ten to twelve days duration, were conducted in the laboratory on return-sludge samples collected from activated sludge treatment plant at Windsor. The thickened sludge samples were blended daily in a waring blender and were continuously aerated in twelve-litres capacity jars. Parallel runs were made on control sludge samples which were not blended. Amongst the parameters varied were the speed and frequency of blending and the aeration rate. The effects of these variables on progressive bio-degradation of volatile suspended solids and the settling characteristics of the sludge were determined. Blended sludge showed significant improvement in the rate of bio-degradation and its settling characteristics as compared to the control unblended sludge

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