Comparison Between Continuous and Batch Flow Activated Sludge Reactor to Remove Nitrate and Phosphate From Domestic Wastewater

The filtration characteristics of two different module configurations with coarse pore filter (non-woven fabric) were investigated for sludge floc separation in an activated sludge reactor for domestic wastewater reclamation. A polypropylene non-woven fabric filter (35 g/m2) was used for the two different module configurations, one flat and one tubular type, each with a filtration area of 0.052 m2. The different module types, submerged in the oxic compartment of A/O (anaerobic/oxic) type reactors, were operated simultaneously. The filtration fluxes were gradually increased from 0.5 to 1.2 and 1.73 m/d. The filtration pressures were more stably maintained for the tubular type module than the plate type. The tubular type module installed horizontally with two-side suction showed less filtration pressures than the tubular type module installed vertically with one-side suction. The solid separation was significantly high showing less than 5 mg/L effluent solids. The organic and T-N removal efficiencies were around 95 and 50%, respectively. The 85% removal of T-P was achieved with 20 mg/L injection of PAC (poly-aluminum chloride).

Download Full-text

Non-woven fabric filter separation activated sludge reactor for domestic wastewater reclamation

Water Science & Technology ◽

10.2166/wst.2003.0035 ◽

2003 ◽

Vol 47 (1) ◽

pp. 133-138 ◽

Cited By ~ 40

Author(s):

G.T. Seo ◽

B.H. Moon ◽

T.S. Lee ◽

T.J. Lim ◽

I.S. Kim

Keyword(s):

Activated Sludge ◽

Domestic Wastewater ◽

Woven Fabric ◽

Wastewater Reclamation ◽

Permeate Flux ◽

Liquid Separation ◽

Fabric Filter ◽

Activated Sludge Reactor ◽

Solid Liquid ◽

Solid Liquid Separation

A non-woven fabric filter was experimentally evaluated for solid-liquid separation in an activated sludge reactor as an alternative membrane. A polypropylene fabric filter (70, 50 and 35 g/m2) was used for the experiment. The pilot system was operated in A/O (Anaerobic/Oxic) type in which the filter module was submerged into the oxic compartment. The filtration module consists of 10 plate type rectangular filter elements with effective filtration area, 2 m2. Gravity filtration was carried out for solid-liquid separation by changing the water head 0.05–0.5 m without backwashing during the system operation. Initial permeate flux was set at 0.4 m/d. C/N ratio of raw wastewater was controlled at 4.5 in terms of BOD/T-N. The fabric filter system showed a good performance enough for domestic wastewater treatment. Effluent solid concentration was 3.2 mg/L (93.5% removal). COD removal efficiency was 91.6% producing an effluent concentration around 13 mg/L. 66% of total nitrogen removal could be obtained at the adjusted C/N ratio of influent wastewater. However phosphorus removal was very low at 23%. It was found that the initial flux of 0.4 m/d should be maintained for stable performance of the system.

Download Full-text

A Batch Activated Sludge Study of Pineapple Wastewater Using a Bioaugmentation Process

Water Science & Technology ◽

10.2166/wst.1991.0129 ◽

1991 ◽

Vol 24 (5) ◽

pp. 233-240 ◽

Cited By ~ 3

Author(s):

Nik Fuaad Nik Abllah ◽

Aik Heng Lee

Keyword(s):

Activated Sludge ◽

Removal Efficiency ◽

Treatment Plant ◽

Domestic Wastewater ◽

Ammonia Nitrogen ◽

Batch Reactors ◽

Organic Loading ◽

Suitable Alternative ◽

Organic Removal ◽

Sludge Production

A laboratory study was conducted to determine the feasibility of batch activated sludge reactor for treating pineapple wastewater and to examine the effects of bioaugmentation on treatment performance. The experimental set-up consists of eleven batch reactors. Activated sludge obtained from a wastewater treatment plant treating domestic wastewater was used as seed for the reactors. Synthetic pineapple wastewater was used as feed for the reactors. The eleven reactors were arranged to evaluate the total organic removal, nitrification, and sludge production by bioaugmentation process. Three major factors considered were influent organic loading, ammonia-nitrogen, and dosage of bacterial-culture-product addition. Removal of TOG (total organic carbon), sludge production in terms of SS(suspended solids), and ammonia-nitrogen removal variation are used as evaluation parameters. The TOC removal efficiency after the end of a 48 hour reactor run, for influent TOC of 350.14 to 363.30 mg/l, and 145.92 to 169.66 mg/l, was 94.41 to 95.89%, and 93.72 to 94.73% respectively. Higher organic removal was observed in the bioaugmented reactors with higher organic loading. The better organic removal efficiency in the bioaugmented reactors was probably due to activities of bacteria added. The test results also indicated that sludge yield was enhanced by the bacteria additive and high bacteria dosage produced less sludge. Bioaugmentation was observed to be a suitable alternative for enhancing the biological treatment of pineapple wastewater.

Download Full-text

Efficiency and Technological Reliability of Contaminant Removal in Household WWTPs with Activated Sludge

Applied Sciences ◽

10.3390/app11041889 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1889 ◽

Cited By ~ 1

Author(s):

Agnieszka Micek ◽

Krzysztof Jóźwiakowski ◽

Michał Marzec ◽

Agnieszka Listosz ◽

Tadeusz Grabowski

Keyword(s):

Activated Sludge ◽

Wastewater Treatment Plants ◽

Oxygen Demand ◽

Domestic Wastewater ◽

Pollutant Removal ◽

Treated Wastewater ◽

Contaminant Removal ◽

Nitrogen And Phosphorus ◽

Wastewater Samples ◽

Polish Law

The results of research on the efficiency and technological reliability of domestic wastewater purification in two household wastewater treatment plants (WWTPs) with activated sludge are presented in this paper. The studied facilities were located in the territory of the Roztocze National Park (Poland). The mean wastewater flow rate in the WWTPs was 1.0 and 1.6 m3/day. In 2017–2019, 20 series of analyses were done, and 40 wastewater samples were taken. On the basis of the received results, the efficiency of basic pollutant removal was determined. The technological reliability of the tested facilities was specified using the Weibull method. The average removal efficiencies for the biochemical oxygen demand in 5 days (BOD5) and chemical oxygen demand (COD) were 66–83% and 62–65%, respectively. Much lower effects were obtained for total suspended solids (TSS) and amounted to 17–48%, while the efficiency of total phosphorus (TP) and total nitrogen (TN) removal did not exceed 34%. The analyzed systems were characterized by the reliability of TSS, BOD5, and COD removal at the level of 76–96%. However, the reliability of TN and TP elimination was less than 5%. Thus, in the case of biogenic compounds, the analyzed systems did not guarantee that the quality of treated wastewater would meet the requirements of the Polish law during any period of operation. This disqualifies the discussed technological solution in terms of its wide application in protected areas and near lakes, where the requirements for nitrogen and phosphorus removal are high.

Download Full-text

Simultaneous removal of BOD, N and P in a single continuous flow real scale activated sludge reactor with cyclic aeration

Water Practice & Technology ◽

10.2166/wpt.2020.012 ◽

2020 ◽

Vol 15 (1) ◽

pp. 201-212

Author(s):

Álvaro Orozco-Jaramillo ◽

Santiago Vélez-Velásquez

Keyword(s):

Continuous Flow ◽

Treatment Plant ◽

Domestic Wastewater ◽

Aeration Tank ◽

Domestic Wastewater Treatment ◽

Stable Conditions ◽

Activated Sludge Reactor ◽

Anoxic Environment ◽

Real Scale ◽

Composite Samples

Abstract The present study evaluates the performance of a real scale domestic wastewater treatment plant (WWTP), operating under continuous flow conditions with ‘extremely high sludge age’, designed to remove organic matter and perform nitrification-denitrification within a single reactor under cyclic aeration. Composite samples were withdrawn from the reactor for one week and their analysis results compared satisfactorily with the calculations of the design models. The WWTP is operating under stable conditions with a BOD5 removal of 86%, COD removal of 87%, TKN removal of 73% and, unexpectedly, a stable removal of 55% of total phosphorus. The design of the WWTP is simple and consists of a single aeration tank with a kinetic selector and a secondary sedimentation tank, operating under cyclic conditions in the aeration tank, with 45-minute aeration on (oxic environment) and 15 minutes aeration off (anoxic environment). The system can be applied to upgrade WWTP from secondary to tertiary treatment with only small modifications. A phosphorus removal mechanism is also proposed.

Download Full-text

Advanced Treatment of Domestic Wastewater Using Sequencing Batch Reactor Activated Sludge Process

Water Science & Technology ◽

10.2166/wst.1993.0243 ◽

1993 ◽

Vol 28 (10) ◽

pp. 267-274 ◽

Cited By ~ 6

Author(s):

M. Imura ◽

E. Suzuki ◽

T. Kitao ◽

S. Iwai

Keyword(s):

Activated Sludge ◽

Sequencing Batch Reactor ◽

Batch Reactor ◽

Domestic Wastewater ◽

Experimental Period ◽

Small Scale ◽

Experimental Plant ◽

Activated Sludge Process ◽

Nitrogen And Phosphorus ◽

Experimental Apparatus

In order to apply a sequencing batch reactor activated sludge process to small scale treatment facilities, various experiments were conducted by manufacturing an experimental apparatus made of a factory-produced FRP cylinder transverse tank (Ø 2,500mm). Results of the verification test conducted for one year by leading the wastewater discharged from apartment houses into the experimental apparatus were as follows. Excellent performance was achieved without any addition of carbon source, irrespective of the organic compound concentration and the temperature of raw wastewater. Organic substances, nitrogen and phosphorus were removed simultaneously. Due to the automated operation format, stable performance was obtained with only periodic maintenance. Though water depth of the experimental plant was shallow, effective sedimentation of activated sludge was continued during the experimental period. Regarding the aerobic and anaerobic process, nitrification and denitrification occurred smoothly.

Download Full-text