The Operation and Maintenance of Small Scale Wastewater Treatment Plants

1986 ◽  
Vol 18 (7-8) ◽  
pp. 313-318
Author(s):  
M. Takahashi
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
Batch Reactor ◽  
Plug Flow ◽  
Small Scale ◽  
Oxidation Ditch ◽  
Excess Sludge ◽  
Treatment Processes ◽  
Operation And Maintenance ◽  
Methods Of Operation

Three wastewater treatment processes (oxidation ditch, extended aeration (plug flow type) and activated sludge batch reactor) which are considered to be suitable for small scale wastewater treatment plants were tested at a pilot plant, or using existing facilities to examine their methods of operation and maintenance. The objectives of this study were to determine production of excess sludge, a method of setting aeration intensity, and a method of controlling returned sludge.

scholarly journals Occurrence and Removal of Veterinary Antibiotics in Livestock Wastewater Treatment Plants, South Korea

Processes ◽  
2020 ◽  
Vol 8 (6) ◽  
pp. 720 ◽  
Author(s):  
Jin-Pil Kim ◽  
Dal Rae Jin ◽  
Wonseok Lee ◽  
Minhee Chae ◽  
Junwon Park
Keyword(s):  
Wastewater Treatment ◽  
South Korea ◽  
Removal Efficiency ◽  
Wastewater Treatment Plants ◽  
Batch Reactor ◽  
Veterinary Antibiotics ◽  
Livestock Wastewater ◽  
Treatment Processes ◽  
Removal Efficiencies ◽  
A2o Process

In this study, livestock wastewater treatment plants in South Korea were monitored to determine the characteristics of influent and effluent wastewater, containing four types of veterinary antibiotics (sulfamethazine, sulfathiazole, chlortetracycline, oxytetracycline), and the removal efficiencies of different treatment processes. Chlortetracycline had the highest average influent concentration (483.7 μg/L), followed by sulfamethazine (251.2 μg/L), sulfathiazole (230.8 μg/L) and oxytetracycline (25.7 μg/L), at five livestock wastewater treatment plants. Sulfathiazole had the highest average effluent concentration (28.2 μg/L), followed by sulfamethazine (20.8 μg/L) and chlortetracycline (11.5 μg/L), while no oxytetracycline was detected. For veterinary antibiotics in the wastewater, a removal efficiency of at least 90% was observed with five types of treatment processes, including a bio-ceramic sequencing batch reactor, liquid-phase flotation, membrane bioreactor, bioreactor plus ultrafiltration (BIOSUF) and bio best bacillus systems. Moreover, this study evaluated the removal efficiency via laboratory-scale experiments on the conventional contaminants, such as organic matter, nitrogen, phosphorus and veterinary antibiotics. This was done using the hydraulic retention time (HRT), under three temporal conditions (14 h, 18 h, 27 h), using the anaerobic–anoxic–oxic (A2O) process, in an attempt to assess the combined livestock wastewater treatment process where the livestock wastewater is treated until certain levels of water quality are achieved, and then the effluent is discharged to nearby sewage treatment plants for further treatment. The removal efficiencies of veterinary antibiotics, especially oxytetracycline and chlortetracycline, were 86.5–88.8% and 87.9–90.8%, respectively, exhibiting no significant differences under various HRT conditions. The removal efficiency of sulfamethazine was at least 20% higher at HRT = 27 h than at HRT = 14 h, indicating that sulfamethazine was efficiently removed in the A2O process with increased HRT. This study is expected to promote a comprehensive understanding of the behavior and removal of veterinary antibiotics in the livestock wastewater treatment plants of South Korea.

A review on sludge conditioning by sludge pre-treatment with a focus on advanced oxidation

RSC Advances ◽  
2014 ◽  
Vol 4 (92) ◽  
pp. 50644-50652 ◽  
Author(s):  
Xu Zhou ◽  
Guangming Jiang ◽  
Qilin Wang ◽  
Zhiguo Yuan
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
Advanced Oxidation ◽  
Biological Wastewater Treatment ◽  
Excess Sludge ◽  
Treatment Processes ◽  
Sludge Conditioning ◽  
Pre Treatment

The production of excess sludge by biological wastewater treatment processes has been a serious issue for the operation of wastewater treatment plants (WWTP) on both the economic and environmental sides.

scholarly journals Mathematical Description of Sequencing Batch Reactor operation of treatment of wastewater with low concentration of organic contaminations

2020 ◽  
Vol 180 ◽  
pp. 04017
Author(s):  
Elena Gogina
Keyword(s):  
Wastewater Treatment ◽  
Biological Treatment ◽  
Sequencing Batch Reactor ◽  
Wastewater Treatment Plants ◽  
Batch Reactor ◽  
Reactor Operation ◽  
Organic Contamination ◽  
Low Concentration ◽  
Treatment Processes ◽  
Biological Treatment System

The paper is oriented towards the study of certain small wastewater-treatment plants, in particular the study of some treatment processes where the wastewater has low concentration of organic contamination. The primary goal of this paper was to obtain the characteristics of a biological treatment system which comply with the laws of enzyme kinetics. The design formulas of the Sequencing Batch Reactor with an inflow of wastewater and low concentration of organic contaminations has been obtained.

Status Analysis on Construction and Operational Effectiveness of Municipal Wastewater Treatment Plants in Guangxi

2014 ◽  
Vol 587-589 ◽  
pp. 808-811
Author(s):  
Qiong Fang Wu ◽  
Guan Wen Cheng ◽  
Ning Shu Liang ◽  
Xu Jiang Qin ◽  
Biao Han ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Municipal Wastewater ◽  
Loading Rate ◽  
Wastewater Treatment Plants ◽  
Sewage Treatment ◽  
Small Scale ◽  
Municipal Wastewater Treatment ◽  
Oxidation Ditch ◽  
Sewage Treatment Plants ◽  
Municipal Wastewater Treatment Plants

In “Eleventh Five-Year” period, Guangxi has vigorously promoted the construction of municipal wastewater treatment plants. The statistics about construction scale shows that most of sewage treatment plants are small-scale. The main processes adopted in the plants are Oxidation ditch(OD), A²/O and SBR and its improved processes. The loading rate is generally low. COD and BOD removal effect are 78% and 87%. In scale of below 2×104m³/d, 2-5×104m³/d,5-10×104m³/d and more than 10×104m³/d, the costs of Diatomite, Oxidation ditch(OD), Oxidation ditch(OD), A²/O processes are relatively provincial, respectively. Meanwhile, the running costs of sewage treatment plants are mainly affected by the scale of construction and loading rate.

scholarly journals Detection and Molecular Characterization of Hepatitis A Virus from Tunisian Wastewater Treatment Plants with Different Secondary Treatments

2016 ◽  
Vol 82 (13) ◽  
pp. 3834-3845 ◽  
Author(s):  
Imen Ouardani ◽  
Syrine Turki ◽  
Mahjoub Aouni ◽  
Jesús L. Romalde
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Molecular Characterization ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Wastewater Treatment Plants ◽  
Genotype Distribution ◽  
Oxidation Ditch ◽  
Conventional Activated Sludge ◽  
Treatment Processes

ABSTRACTHepatitis A virus (HAV) is the main causative agent of hepatitis infection associated with waterborne outbreaks worldwide. In Tunisia, there is no specific surveillance system for HAV and current secondary wastewater treatment processes are unable to remove viral particles, which present a potential public health problem. Qualitative and quantitative analysis of HAV in 271 raw and treated wastewater samples from five sewage treatment plants (STPs) during 13 months was performed. Moreover, the efficiency of three secondary wastewater treatment processes (conventional activated sludge, extended aeration, and oxidation ditch activated sludge) was evaluated. Data obtained demonstrated that HAV is endemic in Tunisia and circulates with high prevalence in both raw (66.9%) and treated (40.7%) wastewater. HAV circulates throughout the year in the coastal areas, with the highest rates found during summer and autumn, whereas in central Tunisia, high levels were shown in autumn and winter. Total virus removal was not achieved, since no difference in mean HAV loads was observed in effluents (6.0 × 103genome copies [GC]/ml) and influents (2.7 × 103GC/ml). The comparison of the HAV removal values of the three different wastewater treatment methods indicates that extended aeration and oxidation ditch activated sludge had better efficiency in removing viruses than conventional activated sludge did. Molecular characterization revealed that the vast majority of HAV strains belonged to subgenotype IA, with the cocirculation of subgenotype IB in wastewater treatment plants that collect tourism wastewater.IMPORTANCEThis report provides important data on the incidence, behavior, seasonality, and genotype distribution of HAV in the environment in Tunisia, as well as the risk of infection derived from its occurrence in effluents due to inadequate wastewater treatment. In addition, these findings seem to confirm that the prevalence of HAV depends on socioeconomic level, sanitary conditions in the communities, sewage facilities, the locality, and the climate. The wide dispersion of HAV in effluents proves the inefficacity of the current wastewater treatment processes used in Tunisia to remove virus; therefore, establishment of tertiary treatment processes or replacement of the medium-charge activated sludge (conventional activated sludge) by the low-charge version (oxidation ditch activated sludge) is absolutely needed. Rapid detection of the HAV genome in wastewater may provide a timely warning sign to health authorities to implement population protection measures.

The Characteristics of Community Wastewater Biological Treatment Processes in Taiwan

1986 ◽  
Vol 18 (7-8) ◽  
pp. 289-296
Author(s):  
C. F. Ouyang ◽  
T. J. Wan
Keyword(s):  
Biological Treatment ◽  
Wastewater Treatment Plants ◽  
Oxygen Demand ◽  
Field Investigation ◽  
Oxidation Ditch ◽  
Trickling Filter ◽  
Rotating Biological Contactor ◽  
Treatment Processes ◽  
Treatment Characteristics ◽  
Sludge Thickening

This study investigated and compared the treatment characteristics of three different kinds of biological wastewater treatment plants (including rotating biological contactor, trickling filter and oxidation ditch) which are currently operated in Taiwan. The field investigation of this study concentrated on the following items: the performance of biological oxygen demand (BOD) and suspended solids (SS) removal; the sludge yield rate of BOD removal; the settleability of sludge solids; the properties of sludge thickening; the power consumption and land area requirement per unit volume of wastewater. Finally, based on the results of the field investigation, a comparison of the treatment characteristics of the three different biological treatment processes was evaluated.

Planning Replicable Small Flow Wastewater Treatment Facilities in Developing Nations

1993 ◽  
Vol 28 (10) ◽  
pp. 1-8 ◽  
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.

scholarly journals Occurrence of SARS-CoV-2 RNA in Six Municipal Wastewater Treatment Plants at the Early Stage of COVID-19 Pandemic in The United States

Pathogens ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 798
Author(s):  
Samendra P. Sherchan ◽  
Shalina Shahin ◽  
Jeenal Patel ◽  
Lauren M. Ward ◽  
Sarmila Tandukar ◽  
...  
Keyword(s):  
United States ◽  
Wastewater Treatment ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Quantitative Polymerase Chain Reaction ◽  
The United States ◽  
Secondary Effluent ◽  
Untreated Wastewater ◽  
Treatment Processes ◽  
Wastewater Samples

In this study, we investigated the occurrence of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) RNA in primary influent (n = 42), secondary effluent (n = 24) and tertiary treated effluent (n = 34) collected from six wastewater treatment plants (WWTPs A–F) in Virginia (WWTP A), Florida (WWTPs B, C, and D), and Georgia (WWTPs E and F) in the United States during April–July 2020. Of the 100 wastewater samples analyzed, eight (19%) untreated wastewater samples collected from the primary influents contained SARS-CoV-2 RNA as measured by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) assays. SARS-CoV-2 RNA were detected in influent wastewater samples collected from WWTP A (Virginia), WWTPs E and F (Georgia) and WWTP D (Florida). Secondary and tertiary effluent samples were not positive for SARS-CoV-2 RNA indicating the treatment processes in these WWTPs potentially removed SARS-CoV-2 RNA during the secondary and tertiary treatment processes. However, further studies are needed to understand the log removal values (LRVs) and transmission risks of SARS-CoV-2 RNA through analyzing wastewater samples from a wider range of WWTPs.

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