Oxygen transfer in gravity flow sewers

1995 ◽  
Vol 31 (7) ◽  
pp. 127-135 ◽  
Author(s):  
P. Balmér ◽  
M. Tagizadeh-Nasser
Keyword(s):  
Energy Dissipation ◽  
Oxygen Transfer ◽  
Laboratory Tests ◽  
Field Studies ◽  
Gravity Flow ◽  
Clean Water

Oxygen transfer to water in gravity flow pipes has been studied in a 24 m long, 0.225 m diameter sewer. Laboratory tests were conducted where the slope and flow in the sewer could be varied independently. The clean water reaeration test was used to determine the oxygen transfer. The KL value for the oxygen transfer was found to be a function of energy dissipation and mean hydraulic depth. The results are discussed in relation to oxygen transfer determinations in flumes and field studies of oxygen transfer in sewers.

The fate of detergent surfactants in sewer systems

1995 ◽  
Vol 31 (7) ◽  
pp. 321-328 ◽  
Author(s):  
E. Matthijs ◽  
G. Debaere ◽  
N. Itrich ◽  
P. Masscheleyn ◽  
A. Rottiers ◽  
...  
Keyword(s):  
Fatty Alcohol ◽  
Half Life ◽  
Laboratory Tests ◽  
Field Experiments ◽  
Sewage Treatment ◽  
Field Studies ◽  
Municipal Sewage ◽  
Alcohol Ethoxylate ◽  
Rapid Reduction ◽  
Laboratory Findings

The fate of detergent surfactants in the sewer can be studied both in laboratory tests and in field experiments. The laboratory studies can be used to determine the rate of disappearance of a test molecule as a function of residence time and estimate its half-life in a given habitat. In addition, important information can be obtained on the mechanism of degradation. Field studies can determine the actual environmental concentrations of surfactants in raw sewage which can then be compared with the expected concentration based on consumption volumes. The difference between the measured and predicted concentration provides an estimate for the disappearance of the test chemical during its travel in the sewer and confirms the results of the laboratory tests. This paper focuses on the fate of a number of important representative anionic, nonionic and cationic surfactants, in the sewer. The results of laboratory die-away studies showed that, in general, the half-life for disappearance in the sewer was in the order of hours for Fatty Alcohol Ethoxylate (AE), Fatty Alcohol Ethoxy Sulphate (AES) and Di-Ethyl-Ester Di-methyl-Ammonium Chloride (DEEDMAC). These laboratory findings for AES were confirmed by monitoring actual raw sewage reaching municipal sewage treatment plants. In addition, a field study demonstrated that the concentration of glucose amides (GA) is considerably reduced during its travel in the sewer. These complementary laboratory and field studies provide key information for the safety assessment of surfactants. They demonstrate that the concentration of surfactants can be significantly reduced in the sewer resulting in a rapid reduction of the environmental loading, which is particularly important in environmental situations where inadequate or no sewage treatment exists.

Oxygen transfer and energy dissipation rate in surface aerator

2009 ◽  
Vol 100 (11) ◽  
pp. 2886-2888 ◽  
Author(s):  
Bimlesh Kumar ◽  
Achanta Ramakrishna Rao
Keyword(s):  
Energy Dissipation ◽  
Oxygen Transfer ◽  
Dissipation Rate ◽  
Energy Dissipation Rate

scholarly journals Geotechnical aspects of locating the Łagiewnicka Route on the area of the “White Seas” in Kraków

2018 ◽  
Vol 36 ◽  
pp. 03006 ◽  
Author(s):  
Jakub Zięba ◽  
Mirosława Bazarnik
Keyword(s):  
Numerical Model ◽  
Laboratory Tests ◽  
Field Studies ◽  
Test Results ◽  
Sheet Pile ◽  
Anthropogenic Soils ◽  
John Paul Ii ◽  
Land Surveying ◽  
Horizontal Thrust ◽  
The Impact

The article presents the results of field studies and laboratory tests of the subsoil of the section of the „Łagiewnicka” route located on the area of so-called “White Seas” [1] in Kraków-Łagiewniki. The analysed samples come from the layer of anthropogenic soils being the result of the operation of the Solvay Sodium Plant in the 20th century. The results of the geotechnical and land-surveying studies served as the basis for developing a numerical model to determine the pressure on the walls of the planned tunnel and the horizontal thrust in the planned excavation. Besides, the study and test results were used to perform an analysis of the excavation’s stability and to check the impact of the sheet pile on land deformations near the John Paul II Centre in Kraków.

scholarly journals Particle separation from road runoff by a decentralised lamella system – laboratory tests and experiences in the field

2017 ◽  
Vol 75 (9) ◽  
pp. 2056-2063 ◽  
Author(s):  
J. Fettig ◽  
V. Pick ◽  
H. Liebe
Keyword(s):  
Laboratory Tests ◽  
Separation Efficiency ◽  
Particle Separation ◽  
Field Studies ◽  
Test Methods ◽  
Road Runoff ◽  
Test Procedures ◽  
Mineral Particles ◽  
Settling Behaviour ◽  
Organic Particles

A new decentralised settling system based on the principle of lamella separation was developed for the treatment of road runoff. Two different laboratory test methods, the DIBt (Deutsches Institut für Bautechnik) procedure and our own approach, were applied in order to evaluate the efficiency of the system based on the separation of fine mineral particles and a mixture of mineral and organic particles, respectively. Overall efficiencies (88% after DIBt and 61% according to our own method) were comparable to results obtained for commercial systems. The lamella system was then applied in the field for 1 year to treat runoff from a road area of 420 m2. The amount of solids separated that was calculated from a mass balance (10.1 kg) was consistent with the amount of sediments measured (8.6 kg). However, the average separation efficiency was only 30% in the field study. This is related to the size and composition of the particles in runoff, which are not represented well by the material used for the test procedures. It is concluded that the test methods should be improved, and that more field studies are needed in order to obtain a better understanding of the settling behaviour of particles in road runoff.

Oxygen transfer rate estimation in oxidation ditches from clean water measurements

2001 ◽  
Vol 35 (8) ◽  
pp. 2058-2064 ◽  
Author(s):  
A. Abusam ◽  
K.J. Keesman ◽  
K. Meinema ◽  
G. van Straten
Keyword(s):  
Oxygen Transfer ◽  
Transfer Rate ◽  
Oxygen Transfer Rate ◽  
Clean Water ◽  
Rate Estimation

Degradation of shaley limestone riprapAn earlier version of this paper was presented at the Canadian Geotechnical Conference in September 2003.

2007 ◽  
Vol 44 (11) ◽  
pp. 1265-1272 ◽  
Author(s):  
James Graham ◽  
Kate Franklin ◽  
Marolo Alfaro ◽  
Joel Wortley
Keyword(s):  
Laboratory Tests ◽  
Water Retention ◽  
Field Studies ◽  
Laboratory Research ◽  
Index Test ◽  
Laboratory Studies ◽  
Freezing And Thawing ◽  
Northern Canada

This paper describes field and laboratory research on limestone riprap at a water retention dyke in northern Canada. Field studies over a period of 5 years showed that weathering had reduced the size of some of the riprap, and hence the protection offered to the dyke. Laboratory tests, including the Iowa pore index test, demonstrate the capacity of the riprap to resist deterioration caused by freezing and thawing. The field and laboratory studies have been complemented by demand calculations.

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