Assessment of the effects of greywater reuse on gross solids movement in sewer systems

Onsite greywater reuse (GWR) and installation of water-efficient toilets (WETs) reduce urban freshwater demand and thus enhance urban water use sustainability. Research on GWR and WETs has generally overlooked their potential effects on municipal sewer systems: GWR and WETs affect the flow regime in sewers, and consequently also influence gross solids transport. To asses these impacts, a gross solids transport model was developed. The model is based on approaches found in the literature. Hydrodynamic calculations of sewage flow were performed using the SIMBA6 simulator and then used for the gross solid movement models. Flow characteristics in the up- and downstream sections of the sewer network differ. Therefore different approaches were used to model solids movement in each of these two parts. Each model determines whether a solid moves as a result of a momentary sewage flow, and if it moves, calculation of its velocity is possible. The paper shows the adoption and implementation of two gross solids transport models using SIMBA6 and depicts the results of the effects of various GWR and WET scenarios on gross solids movement in sewers for a real case study in Israel.

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Comprehensive Planning of Urban Drainage and Wastewater Treatment

Water Science & Technology ◽

10.2166/wst.1993.0302 ◽

1993 ◽

Vol 27 (12) ◽

pp. 205-208

Author(s):

Dirk-Th Kollatsch

Keyword(s):

Wastewater Treatment ◽

Transport Model ◽

Drainage System ◽

Simulation Models ◽

Urban Drainage ◽

Sewer Systems ◽

Priority Task ◽

Treatment Facilities ◽

Receiving Waters ◽

Pollution Impacts

For upgrading the urban drainage system (UDS) the reduction of pollution impacts is the priority task concerning the environmental protection of the receiving waters. With simulation models the interactions between surface, sewer systems, overflow structures and treatment facilities within the UDS can be shown. Models to simulate the pollutant impacts, transport and the effects on the receiving waters are available. In a first step a pollutant transport model of sewer systems and a model to simulate the wastewater treatment processes are connected. With these models the efficiency of upgrading measures can be checked in all parts of urban drainage systems.

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Sediment Transport and Water Flow Resistance in Alluvial River Channels: Modified Model of Transport of Non-Uniform Grain-Size Sediments

Water ◽

10.3390/w13152038 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2038

Author(s):

Gennady Gladkov ◽

Michał Habel ◽

Zygmunt Babiński ◽

Pakhom Belyakov

Keyword(s):

Sediment Transport ◽

Water Flow ◽

Transport Model ◽

Flow Characteristics ◽

Field Measurements ◽

Field Investigation ◽

Empirical Modeling ◽

River Channels ◽

Channel Deformations ◽

East European

The paper presents recommendations for using the results obtained in sediment transport simulation and modeling of channel deformations in rivers. This work relates to the issues of empirical modeling of the water flow characteristics in natural riverbeds with a movable bottom (alluvial channels) which are extremely complex. The study shows that in the simulation of sediment transport and calculation of channel deformations in the rivers, it is expedient to use the calculation dependences of Chézy’s coefficient for assessing the roughness of the bottom sediment mixture, or the dependences of the form based on the field investigation data. Three models are most commonly used and based on the original formulas of Meyer-Peter and Müller (1948), Einstein (1950) and van Rijn (1984). This work deals with assessing the hydraulic resistance of the channel and improving the river sediment transport model in a simulation of riverbed transformation on the basis of previous research to verify it based on 296 field measurements on the Central-East European lowland rivers. The performed test calculations show that the modified van Rijn formula gives the best results from all the considered variants.

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Flow characteristics in a crowded transport model

Nonlinearity ◽

10.1088/0951-7715/29/11/3528 ◽

2016 ◽

Vol 29 (11) ◽

pp. 3528-3550 ◽

Cited By ~ 1

Author(s):

Martin Burger ◽

Jan-Frederik Pietschmann

Keyword(s):

Transport Model ◽

Flow Characteristics

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A non-LTE radiation transport model suitable for multi-dimensional hydrodynamic calculations

IEEE Conference Record - Abstracts. PPPS-2001 Pulsed Power Plasma Science 2001. 28th IEEE International Conference on Plasma Science and 13th IEEE International Pulsed Power Conference (Cat. No.01CH37255) ◽

10.1109/ppps.2001.961036 ◽

2002 ◽

Author(s):

J.W. Thornhill ◽

J.P. Apruzese ◽

J. Davis ◽

R.W. Clark ◽

A.L. Velikovich ◽

...

Keyword(s):

Transport Model ◽

Radiation Transport ◽

Hydrodynamic Calculations ◽

Radiation Transport Model

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SPECTRAL NUMERICAL SIMULATION OF MAGNETO-PHYSIOLOGICAL LAMINAR DEAN FLOW

Journal of Mechanics in Medicine and Biology ◽

10.1142/s021951941450047x ◽

2014 ◽

Vol 14 (04) ◽

pp. 1450047 ◽

Cited By ~ 11

Author(s):

O. ANWAR BEG ◽

MD. MAINUL HOQUE ◽

M. WAHIDUZZAMAN ◽

MD. MAHMUD ALAM ◽

M. FERDOWS

Keyword(s):

Transport Model ◽

Computational Simulation ◽

Large Diameter ◽

Experimental Studies ◽

Circular Cross Section ◽

Flow Characteristics ◽

Axial Flow ◽

Momentum Conservation ◽

Dean Number ◽

Dean Flow

A computational simulation of magnetohydrodynamic laminar blood flow under pressure gradient through a curved bio-vessel, with circular cross-section is presented. Electrical conductivity and other properties of the biofluid (blood) are assumed to be invariant. A Newtonian viscous flow (Navier–Stokes magnetohydrodynamic) model is employed which is appropriate for large diameter blood vessels, as confirmed in a number of experimental studies. Rheological effects are therefore neglected as these are generally only significant in smaller diameter vessels. Employing a toroidal coordinate system, the steady-state, three-dimensional mass and momentum conservation equations are developed. With appropriate transformations, the transport model is non-dimensionalized and further simplified to a pair of axial and secondary flow momenta equations with the aid of a stream function. The resulting non-linear boundary value problem is solved with an efficient, spectral collocation algorithm, subject to physically appropriate boundary conditions. The influence of magnetic body force parameter, Dean number and vessel curvature on the flow characteristics is examined in detail. For high magnetic parameter and Dean number and low curvature, the axial flow is observed to be displaced toward the center of the vessel with corresponding low fluid particle vorticity strengths. Visualization is achieved with the MAPLE software. The simulations are relevant to cardiovascular biomagnetic flow control.

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Prediction of locations with sediment deposits in sewers

Water Science & Technology ◽

10.2166/wst.1996.0198 ◽

1996 ◽

Vol 33 (9) ◽

pp. 147-154 ◽

Cited By ~ 1

Author(s):

Ole Mark ◽

Uros Cerar ◽

Gustavo Perrusquía

Keyword(s):

Sediment Transport ◽

Field Data ◽

Transport Model ◽

Combined Sewer Overflows ◽

Sewer System ◽

Sewer Systems ◽

Sediment Transport Model ◽

Sediment Deposits ◽

Combined Sewer ◽

Movable Bed

The present paper presents an application of MOUSE ST, a general deterministic sediment transport model for sewer systems. MOUSE ST is used to predict the locations subjected to sedimentation in the sewer system of Ljubljana, Slovenia. The prediction is made by means of a sediment transport model with a movable bed. This model is run in parallel with the hydrodynamic MOUSE model. The results, in terms of locations with sediment deposits, are compared with field data from the sewer system in Ljubljana. Further, the model is used to predict the effect of the removal of the sediment deposits on the combined sewer overflows.

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The influence of near bed solids transport on first foul flush in combined sewers

Water Science & Technology ◽

10.2166/wst.1998.0032 ◽

1998 ◽

Vol 37 (1) ◽

pp. 131-138 ◽

Cited By ~ 12

Author(s):

S. Arthur ◽

R. M. Ashley

Keyword(s):

Significant Proportion ◽

Research Programme ◽

Solids Transport ◽

System A ◽

Sewer Systems ◽

Storm Wave ◽

Data Collection Program ◽

Flow Quality ◽

The Uk ◽

Organic Particles

The problems associated with deposited sediments in sewers, and their transport through sewer systems have been the subject of detailed fieldwork programmes in the UK, and elsewhere in Europe. Existing laboratory, and some field based research exercises have focused on the relatively small, discrete particles. It is clear, however, that combined sewer systems have inputs which comprise of a significant proportion of large organic solids (faecal and food wastes), as well as the finer range of particle sizes. The increased concern regarding CSO spills into the environment has fuelled the recent development of sewer flow quality models, such as HYDROWORKS QM and MOUSETRAP, some of which make no attempt to represent the transport of these larger organic particles. Herein, the results of a collaborative research programme undertaken between three UK universities and a water authority are discussed. Transport at the bed in sewers, as “near bed solids”, is defined. Based on a comprehensive data collection program undertaken in the Dundee combined sewerage system, a method is presented which may be used to estimate the rate of sediment transport near the bed in sewers. The influence that solids in transport near the bed have on first foul flush in combined sewers is discussed. A methodology is proposed which may be used to estimate the extent to which sediment in transport near the bed in sewers contributes to first foul flush phenomena, by describing the movement of a storm wave along a conceptual sewer length.

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