Correction to: Effective adsorption of nutrients from simulated domestic sewage by modified maifanite

The performance of two sea outfalls that have been in operation off the coast of Durban for over 10 years has been monitored for effects on the marine environment and public health. The discharge has been a mixture of domestic sewage and industrial waste from which a large proportion of the sludge has been removed but a 2-year research project, in which the balance of the sludge is also being discharged, has commenced. Performance of the outfalls and details of the monitoring programme are reviewed.

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Wastewater Lagoons in a Cold Climate

Water Science & Technology ◽

10.2166/wst.1987.0125 ◽

1987 ◽

Vol 19 (12) ◽

pp. 47-53 ◽

Cited By ~ 4

Author(s):

J. A. Oleszkiewicz ◽

A. B. Sparling

Keyword(s):

Control Mechanism ◽

Maximum Load ◽

Domestic Sewage ◽

Full Scale ◽

Cold Climate ◽

Odor Control ◽

Intermittent Rivers ◽

In Series ◽

Break Up ◽

Lagoon Systems

Severe climate, intermittent rivers and availability of land make facultative lagoon systems the method of choice in treating primarily domestic sewage from smaller municipalities. The lagoons are designed on a recommended maximum load of 55 kgBOD5/ha d to first cell, while the second cell provides storage. The discharge is twice annually and the occurrence of the spring ice break-up odor period is one of the primary criteria limiting this load. Based on full scale performance data, it is demonstrated that, from the standpoint of odor nuisance, the load to the first cell should be kept equal to or less than 35 kg/ha d. Full scale studies of an overloaded lagoon system show the futility of under-ice aeration for odor control. Mechanism of natural odor control during ice break up is elucidated. Upgrading of the overloaded systems or lagoons receiving significant industrial contribution is best achieved by construction of a 3–5 m deep aerated lagoon preceding the two or more facultative cells in series.

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Use of chemical upgrading (CU) in Hungary and Slovakia

Water Science & Technology ◽

10.2166/wst.1994.0227 ◽

1994 ◽

Vol 30 (5) ◽

pp. 87-95 ◽

Cited By ~ 2

Author(s):

Susan E. Murcott ◽

Donald R. F. Harleman

Keyword(s):

Wastewater Treatment ◽

Biological Treatment ◽

Treatment Plant ◽

Domestic Sewage ◽

Metal Salts ◽

Plant Performance ◽

Eastern European ◽

Low Doses ◽

The Past ◽

Treatment Technologies

In the past decade, the development of polymers and new chemical technologies has opened the way to using low doses of chemicals in wastewater treatment. “Chemical upgrading” (CU) is defined in this paper as an application of these chemical technologies to upgrade overloaded treatment systems (typically consisting of conventional primary plus biological treatment) in Central and Eastern European (CEE) countries. Although some of the chemical treatment technologies are proven ones in North America, Scandinavia, and Germany, a host of factors, for example, the variations in composition and degree of pollution, the type of technologies in use, the type and mix of industrial and domestic sewage, and the amount of surface water, had meant that the viability of using CU in CEE countries was unknown. This report describes the first jar tests of CU conducted during the summer of 1993. The experiments show CU's ability to improve wastewater treatment plant performance and to potentially assist in the significant problem of overloaded treatment plants. Increased removal of BOD, TSS, and P in the primary stage of treatment is obtained at overflow rates above 1.5 m/h, using reasonably priced, local sources of metal salts in concentrations of 25 to 50 mg/l without polymers.

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The nitrogen removal potential of predenitrification systems in sensitive coastal areas

Water Science & Technology ◽

10.2166/wst.1995.0218 ◽

1995 ◽

Vol 32 (7) ◽

pp. 135-142

Author(s):

E. Görgün ◽

N. Artan ◽

D. Orhon ◽

R. Tasli

Keyword(s):

Water Quality ◽

Wastewater Treatment ◽

Nitrogen Removal ◽

Retention Time ◽

Treatment Process ◽

Hydraulic Retention Time ◽

Domestic Sewage ◽

Coastal Areas ◽

Careful Evaluation ◽

Denitrification Kinetics

Effective nitrogen removal is now required to protect water quality in sensitive coastal areas. This involves a much more difficult treatment process than for conventional domestic sewage as wastewater quantity and quality exhibits severe fluctuations in touristic zones. Activated sludge is currently the most widely used wastewater treatment and may be upgraded as a predenitrification system for nitrogen removal. Interpretation of nitrification and denitrification kinetics reveal a number of useful correlations between significant parameters such as sludge age, C/N ratio, hydraulic retention time, total influent COD. Nitrogen removal potential of predenitrification may be optimized by careful evaluation of wastewater character and the kinetic correlations.

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The effect of heterotrophic yield on the assessment of the correction factor for anoxic growth

Water Science & Technology ◽

10.2166/wst.1996.0536 ◽

1996 ◽

Vol 34 (5-6) ◽

pp. 67-74 ◽

Cited By ~ 19

Author(s):

D. Orhon ◽

S. Sözen ◽

N. Artan

Keyword(s):

Correction Factor ◽

Domestic Sewage ◽

Yield Coefficient ◽

Heterotrophic Growth ◽

Metabolic Processes ◽

Anoxic Conditions ◽

Industrial Wastewaters ◽

Systems Modelling ◽

Kinetics Of ◽

Very High

For single-sludge denitrification systems, modelling of anoxic reactors currently uses the kinetics of aerobic heterotrophic growth together with a correction factor for anoxic conditions. This coefficient is computed on the basis of respirometric measurements with the assumption that the heterotrophic yield remains the same under aerobic and anoxic coditions. The paper provides the conceptual proof that the yield coefficient is significantly lower for the anoxic growth on the basis of the energetics of the related metabolic processes. This is used for the interpretation of the very high values for the correction factor experimentally determined for a number of industrial wastewaters. A default value for the anoxic heterotrophic yield coefficient is calculated for domestic sewage and compatible wastewaters and proposed for similar evaluations.

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Effect of draft tube diameter on nitrogen removal from domestic sewage in a draft tube type reactor

Water Science & Technology ◽

10.2166/wst.1998.0076 ◽

1998 ◽

Vol 38 (1) ◽

pp. 319-326

Author(s):

Taku Fujiwara ◽

Iso Somiya ◽

Hiroshi Tsuno ◽

Yoshio Okuno

Keyword(s):

Flow Rate ◽

Nitrogen Removal ◽

Draft Tube ◽

Domestic Sewage ◽

Tube Diameter ◽

Continuous Treatment ◽

Anoxic Zone ◽

Type Reactor ◽

Tube Type ◽

Volumetric Loading

The effect of the ratio of draft tube diameter to reactor diameter (Di/Do) on the efficiency of nitrogen removal from domestic sewage is discussed based on liquid-circulating flow rate and continuous treatment data. More than 2.5 minutes of circulation time in the annulus part, which is required to create an anoxic zone, could be maintained under operating conditions in which air flow rate per reactor volume was 2 m3/(m3 · hr) and Di/Do was 0.19. When Di/Do was set at 0.19, the average total organic carbon (TOC), total nitrogen (TN) and dissolved nitrogen (DN) removal efficiencies were 83.2%, 72.1% and 71.6%, respectively, which were higher than those when Di/Do was at 0.26 or 0.36. From these results, it is concluded that 0.19 is the best Di/Do for nitrogen removal in a draft-tube type reactor with an effective depth of 4.0m under the treatment condition in which the BOD volumetric loading rate is in the range 0.22 to 0.46 kgBOD/(m3 · day). More than 80% nitrification and denitrification efficiencies can be achieved simultaneously when both conditions, the aerobic zone ratio being more than 0.2, and the anoxic zone ratio being more than 0.3, are satisfied.

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Evaluation of treatability for two textile mill effluents

Water Science & Technology ◽

10.2166/wst.1999.0032 ◽

1999 ◽

Vol 40 (1) ◽

pp. 145-152 ◽

Cited By ~ 4

Author(s):

F. Germirli Babuna ◽

B. Soyhan ◽

G. Eremektar ◽

D. Orhon

Keyword(s):

Experimental Investigation ◽

Biological Treatment ◽

Chemical Oxidation ◽

Domestic Sewage ◽

Hydrolysis Rate ◽

Textile Mill ◽

Acrylic Fiber ◽

Partial Chemical

The study emphasizes wastewater characteristics of two different textile plants as they apply to biological treatment. Although conventional characterization reveals no major differences, the effluents from the acrylic fiber and yarn dyeing plant exhibit all the properties of a non-biodegradable wastewater. Appropriate pretreatment consisting of partial chemical oxidation with H2O2 reduces its COD content to 700 mg l−1, almost entirely biodegradable whereas COD fractionation indicates that the effluents of the cotton knit dyeing plant contain 9% residual fractions. Experimental investigation shows that most kinetic and stoichiometric properties of both wastewaters are compatible with that of domestic sewage with the exception of a much slower hydrolysis rate.

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Treatment of Rural Domestic Sewage by Solar Ozonic Ecological Sewage Treatment Plant

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.955-959.3393 ◽

2014 ◽

Vol 955-959 ◽

pp. 3393-3399 ◽

Cited By ~ 1

Author(s):

Wei Zheng ◽

Yan Ming Yang ◽

Yun Long Li ◽

Jian Qiu Zheng

Keyword(s):

Municipal Wastewater ◽

Operating Cost ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Domestic Sewage ◽

Design Parameters ◽

Small Scale ◽

Municipal Wastewater Treatment ◽

Average Percentage

The process technique and design parameters of project of Solar Ozonic Ecological Sewage Treatment Plant (short for SOESTP) which consists of anaerobic reactor, horizontal subsurface flow (HSSF) constructed wetlands(CWs) and the combination of solar power and ozone disinfection are described, the paper further examines the removal efficiency for treating rural domestic sewage, running expense and recycling ability of product water. The results show that the average percentage removal values of CODcr，BOD5，SS，TN，NH3-N，TP range from 95.6% to 98.0%, 96.0% to 98.7%, 93.1% to 96.1%, 97.0% to 98.9%, 96.9% to 99.5%, 98.2% to 99.6%, respectively, the reduction of fecal coliform (FC) reaches 99.9%, the effluent quality meets the first level A criteria specified in Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant（GB18918-2002）. The running cost of SOESTP is 0.063yuan/ m3, saves much more than traditional sewage treatment, and the ozone water obtained from the reservoir will be an ideal choice for disinfection .The system has characteristics of easy manipulation, low operating cost, achieving advanced water, energy conservation and environment protection, is thought to be very suitable for use as the promotion of rural small - scale sewage treatment.

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