Investigation of Job Satisfaction and Occupational Safety Perceptions of Employees in Wastewater Treatment Plants: Study of Istanbul

Background: There exist many fatal occupational accidents in the works carried out in wastewater treatment plants. Objective: This research was carried out to determine the relationship between job satisfaction levels and occupational safety perceptions of employees working in wastewater treatment plants. Methods: In this study, a questionnaire including Minnesota Job Satisfaction Scale and Occupational Safety Scale is applied to a total of 161 people aged 16-65 years working in two different Advanced Biological Wastewater Treatment Plants in Istanbul by simple random sampling. Statistical Package for Social Science version-22 was used. Seventeen hypotheses were analyzed to show the relation between the occupational safety perceptions and socio-demographic parameters of employees. Results: The results show that there is no significant relationship between job satisfaction and occupational safety perception of the personnel working in wastewater treatment plants (F=0.096 and p=0.227 >0.05). On the other hand, it is found that there is a statistically significant difference between the level of job satisfaction perception and age of the employees (F=2.358 and p=0.002 <0.05), as well as monthly income ranges (F=4.126 and p=0.008 <0.05). Conclusion: Consequently, the hazards associated with the work should be explained to employees of the wastewater treatment plant in detail. Furthermore, it is suggested to maintain an increase in wages to increase job satisfaction.

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Determining Giardiasis Prevalence by Examination of Sewage

Water Science & Technology ◽

10.2166/wst.1991.0052 ◽

1991 ◽

Vol 24 (2) ◽

pp. 173-178 ◽

Cited By ~ 17

Author(s):

Walter Jakubowski ◽

Jan L. Sykora ◽

Charles A. Sorber ◽

Leonard W. Casson ◽

Patrick D. Gavaghan

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plants ◽

Geometric Mean ◽

Treatment Plant ◽

Geographical Location ◽

Morphological Characteristics ◽

The United States ◽

Giardia Cyst ◽

Significant Difference ◽

Cyst Concentration

Raw sewage samples were collected monthly for one year from 11 wastewater treatment plants located across the United States. Giardia cyst concentrations in the raw sewage were determined by direct count using criteria of size, shape and the presence of two or more internal morphological characteristics for identification. The data were adjusted based on percentage of industrial wastewater reported processed by each plant. Although differences in the adjusted annual geometric mean cyst concentrations were noted among the sites (the highest was 3750 cysts/L and the lowest was 683 cysts/L), there was no correlation of cyst concentration with geographical location as determined by either latitude or longitude. However, when the three southernmost sites were grouped and compared against the group of all remaining sites, there was a significant difference in the annual geometric mean cyst concentration with the southernmost sites being higher. There was no significant association of geometric mean cyst concentration with size of the wastewater treatment plant as represented by mean daily flow. Attempts were made to obtain and correlate giardiasis cases with the monthly cyst levels at each of the sites. Due to reporting problems, low number of cases or unavailability of data, case information was deemed usable for only four of the 11 sites. A significant positive correlation with cases in the community was found at one site. Lack of correlation at other sites was believed to be due to deficiencies in case reporting. The results suggest that sewage examination may be useful for surveillance of Giardia infections in the community.

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Application of a novel sampling bailer device for the analysis of dissolved methane concentrations in municipal wastewater during and following anaerobic treatment

Water Science & Technology ◽

10.2166/wst.2016.150 ◽

2016 ◽

Vol 73 (12) ◽

pp. 2936-2943

Author(s):

David J. Beale ◽

Tim H. Muster ◽

Jason Low ◽

Mark Trickey

Keyword(s):

Wastewater Treatment ◽

Municipal Wastewater ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

Anaerobic Treatment ◽

Methane Recovery ◽

Dissolved Methane ◽

Relative Standard ◽

Significant Difference ◽

Methane Concentrations

Abstract Modern wastewater utilities need to be able to measure and quantify the amount of methane from their treatment facilities in order to understand the potential energy that can be produced and the amount of methane being lost. This paper describes the application of a novel sampling bailer designed for the collection of wastewater samples that minimises methane losses. Samples collected during and following anaerobic treatment from a wastewater treatment plant using a novel sampling bailer were analysed using a previously optimised analytical method. Analysis of wastewater and anaerobic pond samples using current industry approaches resulted in dissolved methane concentrations ranging from 0.01 to 14.33 mg L−1. In comparison, the modified sampling protocol resulted in concentrations ranging from 0.08 to 18.73 mg L−1. The relative standard deviations (RSD%) of low level spikes (5.0 mg L−1 and 0.1 mg L−1 methane; n = 5) were found to be 2.3 and 10.3, respectively. Statistical analysis of the dissolved methane concentrations using the two different approaches demonstrated a significant difference in the recovered dissolved methane concentrations, indicating there is a greater methane recovery potential in wastewater treatment plants than previously realised, when collected using the novel sampling bailer and analysed following the optimised analytical protocol.

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Analysis and balance of phosphorous removal from wastewater at urban wastewater treatment plant

Pollack Periodica ◽

10.1556/606.2020.15.2.13 ◽

2020 ◽

Vol 15 (2) ◽

pp. 142-151

Author(s):

Peter Lukac ◽

Lubos Jurik

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plant ◽

Wastewater Treatment Plants ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Phosphorus Recovery ◽

Anaerobic Sludge ◽

Biological Phosphorus Removal ◽

The Mean

Abstract:Phosphorus is a major substance that is needed especially for agricultural production or for the industry. At the same time it is an important component of wastewater. At present, the waste management priority is recycling and this requirement is also transferred to wastewater treatment plants. Substances in wastewater can be recovered and utilized. In Europe (in Germany and Austria already legally binding), access to phosphorus-containing sewage treatment is changing. This paper dealt with the issue of phosphorus on the sewage treatment plant in Nitra. There are several industrial areas in Nitra where record major producers in phosphorus production in sewage. The new wastewater treatment plant is built as a mechanicalbiological wastewater treatment plant with simultaneous nitrification and denitrification, sludge regeneration, an anaerobic zone for biological phosphorus removal at the beginning of the process and chemical phosphorus precipitation. The sludge management is anaerobic sludge stabilization with heating and mechanical dewatering of stabilized sludge and gas management. The aim of the work was to document the phosphorus balance in all parts of the wastewater treatment plant - from the inflow of raw water to the outflow of purified water and the production of excess sludge. Balancing quantities in the wastewater treatment plant treatment processes provide information where efficient phosphorus recovery could be possible. The mean daily value of P tot is approximately 122.3 kg/day of these two sources. The mean daily value of P tot is approximately 122.3 kg/day of these two sources. There are also two outflows - drainage of cleaned water to the recipient - the river Nitra - 9.9 kg Ptot/day and Ptot content in sewage sludge - about 120.3 kg Ptot/day - total 130.2 kg Ptot/day.

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Sludge minimization by disintegration at different wastewater treatment plants

Water Practice & Technology ◽

10.2166/wpt.2008.010 ◽

2008 ◽

Vol 3 (1) ◽

Author(s):

Luchien Luning ◽

Paul Roeleveld ◽

Victor W.M. Claessen

Keyword(s):

Organic Matter ◽

Wastewater Treatment ◽

Anaerobic Digestion ◽

Sewage Sludge ◽

New Technologies ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

Biological Degradation ◽

Ongoing Research ◽

Sludge Minimization

In recent years new technologies have been developed to improve the biological degradation of sewage sludge by anaerobic digestion. The paper describes the results of a demonstration of ultrasonic disintegration on the Dutch Wastewater Treatment Plant (WWTP) Land van Cuijk. The effect on the degradation of organic matter is presented, together with the effect on the dewatering characteristics. Recommendations are presented for establishing research conditions in which the effect of sludge disintegration can be determined in a more direct way that is less sensitive to changing conditions in the operation of the WWTP. These recommendations have been implemented in the ongoing research in the Netherlands supported by the National Institute for wastewater research (STOWA).

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Planning Replicable Small Flow Wastewater Treatment Facilities in Developing Nations

Water Science & Technology ◽

10.2166/wst.1993.0196 ◽

1993 ◽

Vol 28 (10) ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

A. Gaber ◽

M. Antill ◽

W. Kimball ◽

R. Abdel Wahab

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plants ◽

Local Development ◽

Treatment Plant ◽

Development Program ◽

The United States ◽

Appropriate Technology ◽

Funding Agency ◽

Small Scale ◽

Technology Choice

The implementation of urban village wastewater treatment plants in developing countries has historically been primarily a function of appropriate technology choice and deciding which of the many needy communities should receive the available funding and priority attention. Usually this process is driven by an outside funding agency who views the planning, design, and construction steps as relatively insignificant milestones in the overall effort required to quickly better a community's sanitary drainage problems. With the exception of very small scale type sanitation projects which have relatively simple replication steps, the development emphasis tends to be on the final treatment plant product with little or no attention specifically focused on community participation and institutionalizing national and local policies and procedures needed for future locally sponsored facilities replication. In contrast to this, the Government of Egypt (GOE) enacted a fresh approach through a Local Development Program with the United States AID program. An overview is presented of the guiding principals of the program which produced the first 24 working wastewater systems including gravity sewers, sewage pumping stations and wastewater treatment plants which were designed and constructed by local entities in Egypt. The wastewater projects cover five different treatment technologies implemented in both delta and desert regions.

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Aerial Mapping of Odorous Gases in a Wastewater Treatment Plant Using a Small Drone

Remote Sensing ◽

10.3390/rs13091757 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1757

Author(s):

Javier Burgués ◽

María Deseada Esclapez ◽

Silvia Doñate ◽

Laura Pastor ◽

Santiago Marco

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

Principal Component ◽

Hazardous Air Pollutants ◽

Sampling System ◽

Aerial Mapping ◽

Sensor Signals ◽

Current Monitoring ◽

Flexible Tubes

Wastewater treatment plants (WWTPs) are sources of greenhouse gases, hazardous air pollutants and offensive odors. These emissions can have negative repercussions in and around the plant, degrading the quality of life of surrounding neighborhoods, damaging the environment, and reducing employee’s overall job satisfaction. Current monitoring methodologies based on fixed gas detectors and sporadic olfactometric measurements (human panels) do not allow for an accurate spatial representation of such emissions. In this paper we use a small drone equipped with an array of electrochemical and metal oxide (MOX) sensors for mapping odorous gases in a mid-sized WWTP. An innovative sampling system based on two (10 m long) flexible tubes hanging from the drone allowed near-source sampling from a safe distance with negligible influence from the downwash of the drone’s propellers. The proposed platform is very convenient for monitoring hard-to-reach emission sources, such as the plant’s deodorization chimney, which turned out to be responsible for the strongest odor emissions. The geo-localized measurements visualized in the form of a two-dimensional (2D) gas concentration map revealed the main emission hotspots where abatement solutions were needed. A principal component analysis (PCA) of the multivariate sensor signals suggests that the proposed system can also be used to trace which emission source is responsible for a certain measurement.

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Broad diversity of bacteria degrading 17ß-estradiol-3-sulfate isolated from river sediment and biofilm at a wastewater treatment plant discharge

Archives of Microbiology ◽

10.1007/s00203-021-02409-0 ◽

2021 ◽

Author(s):

Tamara Mainetti ◽

Marilena Palmisano ◽

Fabio Rezzonico ◽

Blaž Stres ◽

Susanne Kern ◽

...

Keyword(s):

Wastewater Treatment ◽

River Sediment ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

Aquatic Environments ◽

Bacterial Isolates ◽

Degrading Bacteria ◽

17Β Estradiol ◽

Aquatic Wildlife ◽

Harmful Effects

AbstractConjugated estrogens, such as 17β-estradiol-3-sulfate (E2-3S), can be released into aquatic environments through wastewater treatment plants (WWTP). There, they are microbiologically degraded into free estrogens, which can have harmful effects on aquatic wildlife. Here, the degradation of E2-3S in environmental samples taken upstream, downstream and at the effluent of a WWTP was assessed. Sediment and biofilm samples were enriched for E2-3S-degrading microorganisms, yielding a broad diversity of bacterial isolates, including known and novel degraders of estrogens. Since E2-3S-degrading bacteria were also isolated in the sample upstream of the WWTP, the WWTP does not influence the ability of the microbial community to degrade E2-3S.

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Comparison of two types of inocula during acclimation and stable operation for nitrophenol biodegradation in an anaerobic-aerobic SBR

Water Science & Technology ◽

10.2166/wst.2006.801 ◽

2006 ◽

Vol 54 (10) ◽

pp. 39-45

Author(s):

A. Vargas ◽

D. González ◽

A. Estival ◽

G. Buitrón

Keyword(s):

Wastewater Treatment ◽

Treatment Plant ◽

The Other ◽

Stable Operation ◽

Reaction Phase ◽

Toxic Compound ◽

Anaerobic Wastewater Treatment ◽

Significant Difference ◽

Different Types ◽

Batch Bioreactors

This work presents a comparison of two inocula used for the acclimation of two anaerobic-aerobic sequencing batch bioreactors used for toxic wastewater treatment. The bioreactors were acclimated with different types of sludge: one coming from an anaerobic wastewater treatment plant and the other one from a conventional aerobic activated sludge plant. The model toxic compound was p-nitrophenol, which is reduced to p-aminophenol during the initial anaerobic phase of the reaction, and later mineralized during a posterior aerated reaction phase. Biodegradation of the compounds was monitored using UV/Vis spectrophotometry. After acclimation stabilization of the sludge and of the process was also monitored. Results show that there is no significant difference in acclimation times and stability of the process between the two employed inocula, and thus an originally anaerobic inoculum presents no apparent advantage over a more easily accessible aerobic one.

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Removal improvement of bacteria (Escherichia coli and enterococci) in maturation ponds using baffles

Water Science & Technology ◽

10.2166/wst.2012.896 ◽

2012 ◽

Vol 65 (4) ◽

pp. 589-595 ◽

Cited By ~ 5

Author(s):

A. Ouali ◽

H. Jupsin ◽

J. L. Vasel ◽

L. Marouani ◽

A. Ghrabi

Keyword(s):

Escherichia Coli ◽

Wastewater Treatment ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

E Coli ◽

Conventional Activated Sludge ◽

In Series ◽

Hydrodynamic Study ◽

Rhodamine Wt ◽

Engineering Intervention

Korba wastewater treatment plant is a conventional activated sludge followed by three maturation ponds (MP1, MP2, MP3) in series acting as a tertiary treatment. The first study of wastewater treatment plants showed that the effluent concentration of Escherichia coli and enterococci at the outlet of the (MP3) varies between 103 and 104CFU/100 ml. After the hydrodynamic study conducted by Rhodamine WT which showed short-circuiting in the MP1, two baffles were introduced in the first maturation pond (MP1) to improve the hydrodynamic and the sanitary performances. The second hydraulic study showed that the dispersion number ‘d’ was reduced from 1.45 to 0.43 by this engineering intervention and the Peclet number was raised from 0.69 to 2.32. The hydraulic retention time was increased by 14 h. Because of well-designed baffles, the removal efficiency of E. coli and enterococci was raised between 0.2 and 0.7 log units for the first maturation pond.

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Biological Nutrient Removal Model No. 2 (BNRM2): a general model for wastewater treatment plants

Water Science & Technology ◽

10.2166/wst.2013.004 ◽

2013 ◽

Vol 67 (7) ◽

pp. 1481-1489 ◽

Cited By ~ 36

Author(s):

R. Barat ◽

J. Serralta ◽

M. V. Ruano ◽

E. Jiménez ◽

J. Ribes ◽

...

Keyword(s):

Wastewater Treatment ◽

Nitrogen Removal ◽

Nutrient Removal ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

Operating Conditions ◽

Plant Performance ◽

Biological Nutrient Removal ◽

Nitrite Oxidizing Bacteria ◽

Removal Model

This paper presents the plant-wide model Biological Nutrient Removal Model No. 2 (BNRM2). Since nitrite was not considered in the BNRM1, and this previous model also failed to accurately simulate the anaerobic digestion because precipitation processes were not considered, an extension of BNRM1 has been developed. This extension comprises all the components and processes required to simulate nitrogen removal via nitrite and the formation of the solids most likely to precipitate in anaerobic digesters. The solids considered in BNRM2 are: struvite, amorphous calcium phosphate, hidroxyapatite, newberite, vivianite, strengite, variscite, and calcium carbonate. With regard to nitrogen removal via nitrite, apart from nitrite oxidizing bacteria two groups of ammonium oxidizing organisms (AOO) have been considered since different sets of kinetic parameters have been reported for the AOO present in activated sludge systems and SHARON (Single reactor system for High activity Ammonium Removal Over Nitrite) reactors. Due to the new processes considered, BNRM2 allows an accurate prediction of wastewater treatment plant performance in wider environmental and operating conditions.

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