Removal and inactivation of cryptosporidium oocysts by activated sludge treatment and anaerobic digestion

1995 ◽  
Vol 31 (5-6) ◽  
pp. 97-104 ◽  
Author(s):  
K. L. Stadterman ◽  
A. M. Sninsky ◽  
J. L. Sykora ◽  
W. Jakubowskii
Keyword(s):  
Wastewater Treatment ◽  
Anaerobic Digestion ◽  
Activated Sludge ◽  
Sewage Treatment ◽  
Treatment Plant ◽  
Sludge Treatment ◽  
Treatment Processes ◽  
Secondary Effluents ◽  
Immunofluorescent Technique ◽  
Cryptosporidium Parvum Oocysts

To determine the fate of Cryptosporidium parvum oocysts during wastewater treatment, a model of an activated sludge treatment plant was designed with a flow of 17 ml/min and a detention time of 6 hours. Samples of raw sewage were seeded with oocysts and primary and secondary effluents were analyzed for C. parvum using an immunofluorescent technique. To compare removal efficiencies of oocysts by various wastewater treatment processes, raw sewage, activated sludge, trickling filter and biodisc effluents were seeded with oocysts and settled for 2 hr and for the respective detention times. Sludge produced by a wastewater treatment plant and anaerobically digested at 37° C in a laboratory digester was also seeded with C. parvum oocysts. Oocyst inactivation was measured by excystation and direct counts. Removal of oocysts in primary and secondary sedimentation averaged 83.4% and 90.7% respectively. The total oocyst removal in sewage treatment averaged 98.6%. In comparison with other treatment processes, activated sludge had the maximum oocyst removal efficiency at 92%. The anaerobic digestion process inactivated 90% of the oocysts within four hours of exposure. 99.9% of the oocysts were eliminated by anaerobic digestion after 24 hours. This demonstrates that the activated sludge process and anaerobic digestion can be effective for the removal and inactivation of C. parvum oocysts.

Dynamic simulation of activated sludge based wastewater treatment processes: Case studies with Titagarh Sewage Treatment Plant, India

Desalination ◽  
2010 ◽  
Vol 252 (1-3) ◽  
pp. 120-126 ◽  
Author(s):  
Ujjaini Sarkar ◽  
Dwaipayan Dasgupta ◽  
Trina Bhattacharya ◽  
Sandip Pal ◽  
Tamaghna Chakroborty
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Case Studies ◽  
Dynamic Simulation ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Treatment Processes

Evaluation of the alternative treatment processes to upgrade an Opium alkaloid wastewater treatment plant

2000 ◽  
Vol 41 (1) ◽  
pp. 223-230 ◽  
Author(s):  
M.F. Sevimli ◽  
A.F. Aydin ◽  
Ì. Öztürk ◽  
H.Z. Sarikaya
Keyword(s):  
Activated Sludge ◽  
Alternative Treatment ◽  
Treatment Plant ◽  
Post Treatment ◽  
Anaerobic Sludge ◽  
Processing Plant ◽  
Two Stage ◽  
Sludge Treatment ◽  
Treatment Processes ◽  
Opium Alkaloid

The aim of this study is to characterize the wastewater from an opium alkaloid processing plant and to evaluate alternative treatment techniques to upgrade an existing full-scale biological activated sludge treatment plant having problems of high residual COD and unacceptable dark brown color. In this content firstly, long term operational records of the two stage aerobic activated sludge treatment plant of the opium alkaloid factory located in Afyon province of Turkiye were evaluated. The operating results for the last three years were statistically analyzed and median and 95-percentile values were determined for the parameters including chemical and biological oxygen demand (COD and BOD5) and treatment efficiencies. Specific wastewater generation was found as 6.7 m3 per ton of the opium capsule processed. In the following stage of the study, three additional treatment processes were experimentally tested: anaerobic pretreatment, post treatment of aerobically treated effluents with lime and ozone. Pilot scale upflow anaerobic sludge blanket reactor (UASBR) experiments have demonstrated that about 70 percent of the incoming COD can be removed anaerobically. Chemical treatability studies with lime for the aerobically treated effluent have shown that about 78 percent color and 46 percent COD removals can be obtained with lime dosage of 25 gl−1. Post treatment of the effluents of the existing two stage aerobic treatment with ozone also resulted in significant color and COD reduction.

Biosolids odor reduction by solids inventory management in the secondary activated sludge treatment system

2009 ◽  
Vol 59 (2) ◽  
pp. 241-247 ◽  
Author(s):  
K. Sekyiamah ◽  
H. Kim
Keyword(s):  
Activated Sludge ◽  
Inventory Management ◽  
Process Parameters ◽  
Treatment Plant ◽  
Treatment System ◽  
Sludge Treatment ◽  
System A ◽  
Treatment Processes ◽  
Dominant Process ◽  
And Control

A wastewater treatment plant consists of unit processes designed to achieve specific waste reduction goals. Offensive odors associated with these treatment processes are a constant source of public complaints. The purpose of this study was to statistically determine the process parameters that influence the formation of volatile sulfur compounds (VSCs) in the secondary treatment system. A statistical model was developed to relate the process parameters to the formation of VSCs in this system. The model established that F/M ratio, sludge blanket depth and SSV60 were the dominant process parameters that influenced the formation of VSCs in the secondary sedimentation basin. This model provides a useful tool for plant engineers to predict and control the VSC formation in a secondary activated sludge treatment system.

Thermochemical pretreatment in the anaerobic digestion of waste activated sludge

2002 ◽  
Vol 46 (10) ◽  
pp. 173-179 ◽  
Author(s):  
S. Tanaka ◽  
K. Kamiyama
Keyword(s):  
Anaerobic Digestion ◽  
Activated Sludge ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Municipal Sewage ◽  
Waste Activated Sludge ◽  
Anaerobic Digesters ◽  
Thermochemical Pretreatment ◽  
Methane Production Rate

Effects of a thermochemical pretreatment on the anaerobic digestion of waste activated sludge (WAS) was investigated by semicontinuously-fed digesters operated at 37¡C. WAS from a return sludge line of a municipal sewage treatment plant was pretreated by autoclaving at 130°C for 5 minutes after adding 0.3g NaOH/g VSS. Solids of WAS were thermochemically solubilized to one half and then 60% or more were in totality solubilized in anaerobic digesters fed with pretreated WAS at 2-8 days of hydraulic retention times (HRT), while only 16-36% were solubilized in digesters fed with raw WAS. The adverse effect of the set temperature (130°C) on the biodegradability of protein was not found. As a result, removal rates of COD in digestion was increased from 38% to 57% at 8 days HRT by the pretreatment. A specific methane production rate in the pretreated process was three times as high as the normal process. The thermochemical pretreatment was found to be very effective to enhance biodegradability as well as solubilization of WAS in anaerobic digestion.

Full-scale control of Mycolata foam by FEX-120 addition

2010 ◽  
Vol 61 (10) ◽  
pp. 2443-2450 ◽  
Author(s):  
C. Kragelund ◽  
B. Nilsson ◽  
K. Eskilsson ◽  
A. M. Bøgh ◽  
P. H. Nielsen
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plant ◽  
No Reduction ◽  
Treatment Plant ◽  
Full Scale ◽  
Filamentous Bacteria ◽  
Gram Positive ◽  
Sludge Treatment ◽  
Scale Control

Foaming incidents in activated sludge treatment plants are a worldwide problem and occur on a regular basis in both municipal and industrial activated sludge treatment plants. Foaming is most often caused by excessive growth of filamentous bacteria, especially the gram-positive ones affiliated within the Actinobacteria, e.g. the branched Mycolata or CandidatusMicrothrix parvicella. Previous studies have shown that populations of Microthrix can be controlled by addition of certain polyaluminium compounds, but until now no effective chemicals have been identified to control other important foam formers such as the Mycolata. A new chemical (FilamentEx, FEX-120) was tested in full-scale in a Swedish wastewater treatment plant (WWTP) with immense foaming problems. In total, three different dosing events were carried out for more than 1 year. After only 8–17 weeks in each period, all foam had disappeared, and dosing of FEX-120 was stopped. Another 11 full-scale WWTPs in different countries were treated with FEX-120 because of severe Mycolata foaming on process tanks. In nine out of 11 plants, where the causative organisms were Gordonia or Skermania, a significant reduction of foam up to 100% was observed after treatment for approx. 10 weeks. In two WWTPs with unknown Mycolata organisms, no reduction was observed.

The Transformation of Heavy Metal Be in Activated Sludge Process

2012 ◽  
Vol 178-181 ◽  
pp. 633-636 ◽  
Author(s):  
Feng Chen ◽  
Xiu Lian Zhu ◽  
Wei Yu
Keyword(s):  
Heavy Metal ◽  
Activated Sludge ◽  
Sewage Treatment ◽  
Great Influence ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Urban Land Use ◽  
Huge Number ◽  
Sludge Treatment

Municipalsludge is refers to the product of sewage treatment plant, facing the huge number of municipalsludge, the disposal of the municipalsludge has aroused wide attention of all countries. Many studies consider that urban land use of the municipalsludge is the most effective method, However heavy metal accumulats in the sludge and the environment of the risk with agricultural appears day after day.The purpose of this study is: analysis the transfermation of heavy metals in the activated sludge system of various structures. put forward the solution of reducing heavy metal exceeded in the activated sludge treatment process.It appears that the coagulation can make colloid stabilized and sedimentation, can control the input of the heavy metal effectively; Adsorption of activated sludge to heavy metal is very fast, in 30 min basic reached adsorption balance, probably 80% or more;The change from oxygen to aerobic have great influence on Heavy metal biological adsorption;An aerobic digestion processes can reduce the volume and quality of sludge, but there is no enrichment role to heavy metal in sludge.

scholarly journals Reliability of removal of selected pollutants in different technological solutions of household wastewater treatment plants

2017 ◽  
Vol 35 (1) ◽  
pp. 141-148 ◽  
Author(s):  
Michał Marzec
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Suspended Solids ◽  
Wastewater Treatment Plants ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Total Suspended Solids ◽  
Hybrid Reactor ◽  
Limit Values

AbstractThe reliability of removal of selected contaminants in three technological solutions of the household sewage treatment plants was analysed in this paper. The reliability of the sewage treatment plant with activated sludge, sprinkled biological deposit and hybrid reactor (activated sludge and immersed trickling filter) was analyzed. The analysis was performed using the Weibull method for basic indicators of impurities, BOD5, COD and total suspended solids. The technological reliability of the active sludge treatment plant was 70% for BOD5, 87% for COD and 66% for total suspended solids. In the sewage treatment plant with a biological deposit, the reliability values determined were: 30% (BOD5), 60% (COD) and 67% (total suspended solids). In a treatment plant with a hybrid reactor, 30% of the BOD5and COD limit values were exceeded, while 30% of the total suspended solids were exceeded. The reliability levels are significantly lower than the acceptable levels proposed in the literature, which means that the wastewater discharged from the analysed wastewater treatment plants often exceeds the limit values of indicators specified in currently valid in Poland Regulation of the Minister of Environment for object to 2000 population equivalent.

scholarly journals Odour nuisance assessment of the food industry wastewater treatment plant

2019 ◽  
Vol 100 ◽  
pp. 00024
Author(s):  
Agnieszka Grzelka ◽  
Elżbieta Romanik ◽  
Urszula Miller
Keyword(s):  
Wastewater Treatment ◽  
Hydrogen Sulphide ◽  
Food Industry ◽  
Reference Model ◽  
Sewage Treatment ◽  
Detection Threshold ◽  
Treatment Plant ◽  
Model Calculations ◽  
Treatment Processes ◽  
Local Residents

Odour nuisance generated by food industry objects is a significant problem, the result of which is often numerous complaints from local residents about the quality of air. Apart from the production process, this problem often concerns industrial wastewater treatment processes, which contribute to a large extent to the emissions of odorants from the sulphur group, including hydrogen sulphide and mercaptans. In order to estimate the odorous air quality around these types of objects, the modelling of dispersion of pollutants: odours or odorants is often used. The paper presents the results of tests on odour emission as well as hydrogen sulphide and mercaptans emission as compounds typical for waste gases from the sewage treatment process from the food industry. In order to estimate the range of odour impact, model calculations using the Polish reference model for the aforementioned substances were made. The values of annual average concentrations and frequency of odour detection thresholds for odorants and odour concentration of 1 ouE/m3 for odours as a mixture in a computational grid of 1400 m x 1400 m with a step of 50 m were calculated. The results showed the highest range of odour impact of mercaptans, whose value of the average annual concentration exceeded the odour detection threshold up to 700 m in the east and west direction from the emission source.

Dynamics in maximal settling capacity in an activated sludge treatment plant with highly loaded secondary settlers

2004 ◽  
Vol 50 (7) ◽  
pp. 187-194 ◽  
Author(s):  
B.-M. Wilén ◽  
D. Lumley ◽  
A. Nordqvist
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Treatment Plant ◽  
Secondary Effluent ◽  
Sludge Treatment ◽  
Trickling Filters ◽  
Secondary Settling ◽  
Determining Factor ◽  
Maximal Capacity ◽  
Highly Loaded

Secondary settling dynamics at maximal capacity were investigated at a full scale wastewater treatment plant which utilizes a unique process solution incorporating pre-denitrification with postnitrification in nitrifying trickling filters. Since nitrogen removal is greater when more secondary effluent is recirculated to the trickling filters, the secondary settlers generally operate at close to their maximal capacity. The settling and flocculation properties of the activated sludge are therefore a major capacity-determining factor for plant operation. Due to the short sludge age, the flocculation properties, with respect to both thickening and clarification, can change quickly. The dynamics in these changes were studied and the factors that determine the maximal settling capacity were assessed. Solids flux curves were constructed from batch settling tests and compared with the actual maximal settling capacities.

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